Merge branch 'main' into macos-correct-stack

.github/.cSpellWords.txt

@@ -448,6 +448,7 @@ MAINRDY
 MAIR
 Mang
 Mbits
+mbranch
 mcause
 MCFR
 MCKA
@@ -586,6 +587,8 @@ OWATCOM
 OWDR
 OWER
 OWSR
+pacbti
+PACBTI
 PAGEN
 PCDR
 PCER
@@ -900,6 +903,7 @@ TXTEN
 TXUBR
 TXVC
 TXVDIS
+UBTI
 UDCP
 UNACKED
 uncrustify
@@ -915,6 +919,7 @@ UNSUB
 UNSUBACK
 unsubscriptions
 unsuspended
+UPAC
 URAD
 URAT
 URSTEN

.github/CODEOWNERS

@@ -4,7 +4,7 @@
 # the repo. Unless a later match takes precedence,
 # @global-owner1 and @global-owner2 will be requested for
 # review when someone opens a pull request.
-*      @FreeRTOS/pr-bar-raiser
+*      @FreeRTOS/pr-bar-raisers
 
 # Order is important; the last matching pattern takes the most
 # precedence. When someone opens a pull request that only

.github/scripts/kernel_checker.py

@@ -28,6 +28,7 @@
 # */
 
 import os
+import re
 from common.header_checker import HeaderChecker
 
 #--------------------------------------------------------------------------------------------------
@@ -106,6 +107,15 @@ KERNEL_THIRD_PARTY_PATTERNS = [
     r'.*portable/GCC/AVR32_UC3/.*',
 ]
 
+KERNEL_ARM_COLLAB_FILES_PATTERNS = [
+    r'.*portable/ARMv8M/*',
+    r'.*portable/.*/ARM_CM23*',
+    r'.*portable/.*/ARM_CM33*',
+    r'.*portable/.*/ARM_CM35*',
+    r'.*portable/.*/ARM_CM55*',
+    r'.*portable/.*/ARM_CM85*',
+]
+
 KERNEL_HEADER = [
     '/*\n',
     ' * FreeRTOS Kernel <DEVELOPMENT BRANCH>\n',
@@ -139,19 +149,92 @@ KERNEL_HEADER = [
 
 FREERTOS_COPYRIGHT_REGEX = r"^(;|#)?( *(\/\*|\*|#|\/\/))? Copyright \(C\) 20\d\d Amazon.com, Inc. or its affiliates. All Rights Reserved\.( \*\/)?$"
 
+FREERTOS_ARM_COLLAB_COPYRIGHT_REGEX = r"(^(;|#)?( *(\/\*|\*|#|\/\/))? Copyright \(C\) 20\d\d Amazon.com, Inc. or its affiliates. All Rights Reserved\.( \*\/)?$)|" + \
+                                      r"(^(;|#)?( *(\/\*|\*|#|\/\/))? Copyright 20\d\d Arm Limited and/or its affiliates( \*\/)?$)|" + \
+                                      r"(^(;|#)?( *(\/\*|\*|#|\/\/))? <open-source-office@arm.com>( \*\/)?$)"
+
+
+class KernelHeaderChecker(HeaderChecker):
+    def __init__(
+        self,
+        header,
+        padding=1000,
+        ignored_files=None,
+        ignored_ext=None,
+        ignored_patterns=None,
+        py_ext=None,
+        asm_ext=None,
+        third_party_patterns=None,
+        copyright_regex = None
+    ):
+        super().__init__(header, padding, ignored_files, ignored_ext, ignored_patterns,
+                         py_ext, asm_ext, third_party_patterns, copyright_regex)
+
+        self.armCollabRegex = re.compile(FREERTOS_ARM_COLLAB_COPYRIGHT_REGEX)
+
+        self.armCollabFilesPatternList = []
+        for pattern in KERNEL_ARM_COLLAB_FILES_PATTERNS:
+            self.armCollabFilesPatternList.append(re.compile(pattern))
+
+    def isArmCollabFile(self, path):
+        for pattern in self.armCollabFilesPatternList:
+            if pattern.match(path):
+                return True
+        return False
+
+    def checkArmCollabFile(self, path):
+        isValid = False
+        file_ext = os.path.splitext(path)[-1]
+
+        with open(path, encoding="utf-8", errors="ignore") as file:
+            chunk = file.read(len("".join(self.header)) + self.padding)
+            lines = [("%s\n" % line) for line in chunk.strip().splitlines()][
+                : len(self.header) + 2
+            ]
+            if (len(lines) > 0) and (lines[0].find("#!") == 0):
+                lines.remove(lines[0])
+
+        # Split lines in sections.
+        headers = dict()
+        headers["text"] = []
+        headers["copyright"] = []
+        headers["spdx"] = []
+        for line in lines:
+            if self.armCollabRegex.match(line):
+                headers["copyright"].append(line)
+            elif "SPDX-License-Identifier:" in line:
+                headers["spdx"].append(line)
+            else:
+                headers["text"].append(line)
+
+        text_equal = self.isValidHeaderSection(file_ext, "text", headers["text"])
+        spdx_equal = self.isValidHeaderSection(file_ext, "spdx", headers["spdx"])
+
+        if text_equal and spdx_equal and len(headers["copyright"]) == 3:
+            isValid = True
+
+        return isValid
+
+    def customCheck(self, path):
+        isValid = False
+        if self.isArmCollabFile(path):
+            isValid = self.checkArmCollabFile(path)
+        return isValid
+
+
 def main():
     parser = HeaderChecker.configArgParser()
     args   = parser.parse_args()
 
     # Configure the checks then run
-    checker = HeaderChecker(KERNEL_HEADER,
+    checker = KernelHeaderChecker(KERNEL_HEADER,
-                            copyright_regex=FREERTOS_COPYRIGHT_REGEX,
+                                  copyright_regex=FREERTOS_COPYRIGHT_REGEX,
-                            ignored_files=KERNEL_IGNORED_FILES,
+                                  ignored_files=KERNEL_IGNORED_FILES,
-                            ignored_ext=KERNEL_IGNORED_EXTENSIONS,
+                                  ignored_ext=KERNEL_IGNORED_EXTENSIONS,
-                            ignored_patterns=KERNEL_IGNORED_PATTERNS,
+                                  ignored_patterns=KERNEL_IGNORED_PATTERNS,
-                            third_party_patterns=KERNEL_THIRD_PARTY_PATTERNS,
+                                  third_party_patterns=KERNEL_THIRD_PARTY_PATTERNS,
-                            py_ext=KERNEL_PY_EXTENSIONS,
+                                  py_ext=KERNEL_PY_EXTENSIONS,
-                            asm_ext=KERNEL_ASM_EXTENSIONS)
+                                  asm_ext=KERNEL_ASM_EXTENSIONS)
     checker.ignoreFile(os.path.split(__file__)[-1])
 
     rc = checker.processArgs(args)

CMakeLists.txt

@@ -138,15 +138,18 @@ if(NOT FREERTOS_PORT)
         " IAR_ARM_CM33_NONSECURE           - Compiler: IAR           Target: ARM Cortex-M33 non-secure\n"
         " IAR_ARM_CM33_SECURE              - Compiler: IAR           Target: ARM Cortex-M33 secure\n"
         " IAR_ARM_CM33_NTZ_NONSECURE       - Compiler: IAR           Target: ARM Cortex-M33 non-trustzone non-secure\n"
+        " IAR_ARM_CM33_TFM                 - Compiler: IAR           Target: ARM Cortex-M33 non-secure for TF-M\n"
         " IAR_ARM_CM35P_NONSECURE          - Compiler: IAR           Target: ARM Cortex-M35P non-secure\n"
         " IAR_ARM_CM35P_SECURE             - Compiler: IAR           Target: ARM Cortex-M35P secure\n"
         " IAR_ARM_CM35P_NTZ_NONSECURE      - Compiler: IAR           Target: ARM Cortex-M35P non-trustzone non-secure\n"
         " IAR_ARM_CM55_NONSECURE           - Compiler: IAR           Target: ARM Cortex-M55 non-secure\n"
         " IAR_ARM_CM55_SECURE              - Compiler: IAR           Target: ARM Cortex-M55 secure\n"
         " IAR_ARM_CM55_NTZ_NONSECURE       - Compiler: IAR           Target: ARM Cortex-M55 non-trustzone non-secure\n"
+        " IAR_ARM_CM55_TFM                 - Compiler: IAR           Target: ARM Cortex-M55 non-secure for TF-M\n"
         " IAR_ARM_CM85_NONSECURE           - Compiler: IAR           Target: ARM Cortex-M85 non-secure\n"
         " IAR_ARM_CM85_SECURE              - Compiler: IAR           Target: ARM Cortex-M85 secure\n"
         " IAR_ARM_CM85_NTZ_NONSECURE       - Compiler: IAR           Target: ARM Cortex-M85 non-trustzone non-secure\n"
+        " IAR_ARM_CM85_TFM                 - Compiler: IAR           Target: ARM Cortex-M85 non-secure for TF-M\n"
         " IAR_ARM_CRX_NOGIC                - Compiler: IAR           Target: ARM Cortex-Rx no GIC\n"
         " IAR_ATMEGA323                    - Compiler: IAR           Target: ATMega323\n"
         " IAR_ATMEL_SAM7S64                - Compiler: IAR           Target: Atmel SAM7S64\n"

examples/coverity/README.md

@@ -17,7 +17,7 @@ files.
 
 ## Getting Started
 ### Prerequisites
-Coverity can be run on any platform mentioned [here](https://sig-docs.synopsys.com/polaris/topics/c_coverity-compatible-platforms.html).
+Coverity can be run on any platform mentioned [here](https://documentation.blackduck.com/bundle/coverity-docs/page/deploy-install-guide/topics/supported_platforms_for_coverity_analysis.html).
 The following are the prerequisites to generate coverity report:
 
 1. CMake version > 3.13.0 (You can check whether you have this by typing `cmake --version`).

include/FreeRTOS.h

@@ -3032,6 +3032,18 @@
     #define configCONTROL_INFINITE_LOOP()
 #endif
 
+/* Set configENABLE_PAC and/or configENABLE_BTI to 1 to enable PAC and/or BTI
+ * support and 0 to disable them. These are currently used in ARMv8.1-M ports. */
+#if ( portHAS_PACBTI_FEATURE == 1 )
+    #ifndef configENABLE_PAC
+        #define configENABLE_PAC    0
+    #endif
+
+    #ifndef configENABLE_BTI
+        #define configENABLE_BTI    0
+    #endif
+#endif
+
 /* Sometimes the FreeRTOSConfig.h settings only allow a task to be created using
  * dynamically allocated RAM, in which case when any task is deleted it is known
  * that both the task's stack and TCB need to be freed.  Sometimes the

portable/ARMv8M/non_secure/port.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -110,6 +112,7 @@ typedef void ( * portISR_t )( void );
 #define portSCB_VTOR_REG                      ( *( ( portISR_t ** ) 0xe000ed08 ) )
 #define portSCB_SYS_HANDLER_CTRL_STATE_REG    ( *( ( volatile uint32_t * ) 0xe000ed24 ) )
 #define portSCB_MEM_FAULT_ENABLE_BIT          ( 1UL << 16UL )
+#define portSCB_USG_FAULT_ENABLE_BIT          ( 1UL << 18UL )
 /*-----------------------------------------------------------*/
 
 /**
@@ -373,6 +376,20 @@ typedef void ( * portISR_t )( void );
  * any secure calls.
  */
 #define portNO_SECURE_CONTEXT    0
+
+/**
+ * @brief Constants required to check and configure PACBTI security feature implementation.
+ */
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    #define portID_ISAR5_REG         ( *( ( volatile uint32_t * ) 0xe000ed74 ) )
+
+    #define portCONTROL_UPAC_EN      ( 1UL << 7UL )
+    #define portCONTROL_PAC_EN       ( 1UL << 6UL )
+    #define portCONTROL_UBTI_EN      ( 1UL << 5UL )
+    #define portCONTROL_BTI_EN       ( 1UL << 4UL )
+
+#endif /* portHAS_PACBTI_FEATURE */
 /*-----------------------------------------------------------*/
 
 /**
@@ -410,6 +427,26 @@ static void prvTaskExitError( void );
     static void prvSetupFPU( void ) PRIVILEGED_FUNCTION;
 #endif /* configENABLE_FPU */
 
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+/**
+ * @brief Configures PACBTI features.
+ *
+ * This function configures the Pointer Authentication, and Branch Target
+ * Identification security features as per the user configuration. It returns
+ * the value of the special purpose CONTROL register accordingly, and optionally
+ * updates the CONTROL register value. Currently, only Cortex-M85 (ARMv8.1-M
+ * architecture based) target supports PACBTI security feature.
+ *
+ * @param xWriteControlRegister Used to control whether the special purpose
+ * CONTROL register should be updated or not.
+ *
+ * @return CONTROL register value according to the configured PACBTI option.
+ */
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister );
+
+#endif /* portHAS_PACBTI_FEATURE */
+
 /**
  * @brief Setup the timer to generate the tick interrupts.
  *
@@ -1457,6 +1494,7 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
                                          xMPU_SETTINGS * xMPUSettings ) /* PRIVILEGED_FUNCTION */
     {
         uint32_t ulIndex = 0;
+        uint32_t ulControl = 0x0;
 
         xMPUSettings->ulContext[ ulIndex ] = 0x04040404; /* r4. */
         ulIndex++;
@@ -1503,16 +1541,24 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
         xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) pxEndOfStack;         /* PSPLIM. */
         ulIndex++;
 
+        #if ( portHAS_PACBTI_FEATURE == 1 )
+        {
+            /* Check PACBTI security feature configuration before pushing the
+             * CONTROL register's value on task's TCB. */
+            ulControl = prvConfigurePACBTI( pdFALSE );
+        }
+        #endif /* portHAS_PACBTI_FEATURE */
+
         if( xRunPrivileged == pdTRUE )
         {
             xMPUSettings->ulTaskFlags |= portTASK_IS_PRIVILEGED_FLAG;
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
         else
         {
             xMPUSettings->ulTaskFlags &= ( ~portTASK_IS_PRIVILEGED_FLAG );
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
 
@@ -1740,6 +1786,14 @@ BaseType_t xPortStartScheduler( void ) /* PRIVILEGED_FUNCTION */
     portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
     portNVIC_SHPR2_REG = 0;
 
+    #if ( portHAS_PACBTI_FEATURE == 1 )
+    {
+        /* Set the CONTROL register value based on PACBTI security feature
+         * configuration before starting the first task. */
+        ( void) prvConfigurePACBTI( pdTRUE );
+    }
+    #endif /* portHAS_PACBTI_FEATURE */
+
     #if ( configENABLE_MPU == 1 )
     {
         /* Setup the Memory Protection Unit (MPU). */
@@ -2158,3 +2212,42 @@ BaseType_t xPortIsInsideInterrupt( void )
 
 #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */
 /*-----------------------------------------------------------*/
+
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister )
+    {
+        uint32_t ulControl = 0x0;
+
+        /* Ensure that PACBTI is implemented. */
+        configASSERT( portID_ISAR5_REG != 0x0 );
+
+        /* Enable UsageFault exception if PAC or BTI is enabled. */
+        #if( ( configENABLE_PAC == 1 ) || ( configENABLE_BTI == 1 ) )
+        {
+            portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_USG_FAULT_ENABLE_BIT;
+        }
+        #endif
+
+        #if( configENABLE_PAC == 1 )
+        {
+            ulControl |= ( portCONTROL_UPAC_EN | portCONTROL_PAC_EN );
+        }
+        #endif
+
+        #if( configENABLE_BTI == 1 )
+        {
+            ulControl |= ( portCONTROL_UBTI_EN | portCONTROL_BTI_EN );
+        }
+        #endif
+
+        if( xWriteControlRegister == pdTRUE )
+        {
+            __asm volatile ( "msr control, %0" : : "r" ( ulControl ) );
+        }
+
+        return ulControl;
+    }
+
+#endif /* #if ( portHAS_PACBTI_FEATURE == 1 ) */
+/*-----------------------------------------------------------*/

portable/ARMv8M/non_secure/portable/GCC/ARM_CM23/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -51,6 +53,7 @@
 #define portARCH_NAME                    "Cortex-M23"
 #define portHAS_ARMV8M_MAIN_EXTENSION    0
 #define portARMV8M_MINOR_VERSION         0
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __attribute__( ( used ) )
 /*-----------------------------------------------------------*/
 

portable/ARMv8M/non_secure/portable/GCC/ARM_CM23_NTZ/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -51,6 +53,7 @@
 #define portARCH_NAME                    "Cortex-M23"
 #define portHAS_ARMV8M_MAIN_EXTENSION    0
 #define portARMV8M_MINOR_VERSION         0
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __attribute__( ( used ) )
 /*-----------------------------------------------------------*/
 

portable/ARMv8M/non_secure/portable/GCC/ARM_CM33/portasm.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -134,8 +136,9 @@
             "   ldr  r4, =xSecureContext                        \n"
             "   str  r1, [r4]                                   \n" /* Set xSecureContext to this task's value for the same. */
             "   msr  psplim, r2                                 \n" /* Set this task's PSPLIM value. */
-            "   movs r1, #2                                     \n" /* r1 = 2. */
+            "   mrs  r1, control                                \n" /* Obtain current control register value. */
-            "   msr  CONTROL, r1                                \n" /* Switch to use PSP in the thread mode. */
+            "   orrs r1, r1, #2                                 \n" /* r1 = r1 | 0x2 - Set the second bit to use the program stack pointer (PSP). */
+            "   msr control, r1                                 \n" /* Write back the new control register value. */
             "   adds r0, #32                                    \n" /* Discard everything up to r0. */
             "   msr  psp, r0                                    \n" /* This is now the new top of stack to use in the task. */
             "   isb                                             \n"

portable/ARMv8M/non_secure/portable/GCC/ARM_CM33/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -51,6 +53,7 @@
 #define portARCH_NAME                    "Cortex-M33"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         0
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __attribute__( ( used ) )
 /*-----------------------------------------------------------*/
 

portable/ARMv8M/non_secure/portable/GCC/ARM_CM33_NTZ/portasm.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -130,8 +132,9 @@
             "                                                   \n"
             "   ldm  r0!, {r1-r2}                               \n" /* Read from stack - r1 = PSPLIM and r2 = EXC_RETURN. */
             "   msr  psplim, r1                                 \n" /* Set this task's PSPLIM value. */
-            "   movs r1, #2                                     \n" /* r1 = 2. */
+            "   mrs  r1, control                                \n" /* Obtain current control register value. */
-            "   msr  CONTROL, r1                                \n" /* Switch to use PSP in the thread mode. */
+            "   orrs r1, r1, #2                                 \n" /* r1 = r1 | 0x2 - Set the second bit to use the program stack pointer (PSP). */
+            "   msr control, r1                                 \n" /* Write back the new control register value. */
             "   adds r0, #32                                    \n" /* Discard everything up to r0. */
             "   msr  psp, r0                                    \n" /* This is now the new top of stack to use in the task. */
             "   isb                                             \n"

portable/ARMv8M/non_secure/portable/GCC/ARM_CM33_NTZ/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -51,6 +53,7 @@
 #define portARCH_NAME                    "Cortex-M33"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         0
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __attribute__( ( used ) )
 /*-----------------------------------------------------------*/
 

portable/ARMv8M/non_secure/portable/GCC/ARM_CM35P/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -51,6 +53,7 @@
 #define portARCH_NAME                    "Cortex-M35P"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         0
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __attribute__( ( used ) )
 /*-----------------------------------------------------------*/
 

portable/ARMv8M/non_secure/portable/GCC/ARM_CM55/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -56,6 +58,7 @@
 #define portARCH_NAME                    "Cortex-M55"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         1
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __attribute__( ( used ) )
 /*-----------------------------------------------------------*/
 

portable/ARMv8M/non_secure/portable/GCC/ARM_CM85/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -56,6 +58,7 @@
 #define portARCH_NAME                    "Cortex-M85"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         1
+#define portHAS_PACBTI_FEATURE           1
 #define portDONT_DISCARD                 __attribute__( ( used ) )
 /*-----------------------------------------------------------*/
 

portable/ARMv8M/non_secure/portable/IAR/ARM_CM23/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -51,6 +53,7 @@
 #define portARCH_NAME                    "Cortex-M23"
 #define portHAS_ARMV8M_MAIN_EXTENSION    0
 #define portARMV8M_MINOR_VERSION         0
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __root
 /*-----------------------------------------------------------*/
 

portable/ARMv8M/non_secure/portable/IAR/ARM_CM23_NTZ/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -51,6 +53,7 @@
 #define portARCH_NAME                    "Cortex-M23"
 #define portHAS_ARMV8M_MAIN_EXTENSION    0
 #define portARMV8M_MINOR_VERSION         0
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __root
 /*-----------------------------------------------------------*/
 

portable/ARMv8M/non_secure/portable/IAR/ARM_CM33/portasm.s

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -179,8 +181,9 @@ vRestoreContextOfFirstTask:
     ldr  r4, =xSecureContext
     str  r1, [r4]                           /* Set xSecureContext to this task's value for the same. */
     msr  psplim, r2                         /* Set this task's PSPLIM value. */
-    movs r1, #2                             /* r1 = 2. */
+    mrs  r1, control                        /* Obtain current control register value. */
-    msr  CONTROL, r1                        /* Switch to use PSP in the thread mode. */
+    orrs r1, r1, #2                         /* r1 = r1 | 0x2 - Set the second bit to use the program stack pointe (PSP). */
+    msr control, r1                         /* Write back the new control register value. */
     adds r0, #32                            /* Discard everything up to r0. */
     msr  psp, r0                            /* This is now the new top of stack to use in the task. */
     isb

portable/ARMv8M/non_secure/portable/IAR/ARM_CM33/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -51,6 +53,7 @@
 #define portARCH_NAME                    "Cortex-M33"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         0
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __root
 /*-----------------------------------------------------------*/
 

portable/ARMv8M/non_secure/portable/IAR/ARM_CM33_NTZ/portasm.s

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -165,8 +167,9 @@ vRestoreContextOfFirstTask:
 
     ldm  r0!, {r1-r2}                       /* Read from stack - r1 = PSPLIM and r2 = EXC_RETURN. */
     msr  psplim, r1                         /* Set this task's PSPLIM value. */
-    movs r1, #2                             /* r1 = 2. */
+    mrs  r1, control                        /* Obtain current control register value. */
-    msr  CONTROL, r1                        /* Switch to use PSP in the thread mode. */
+    orrs r1, r1, #2                         /* r1 = r1 | 0x2 - Set the second bit to use the program stack pointe (PSP). */
+    msr control, r1                         /* Write back the new control register value. */
     adds r0, #32                            /* Discard everything up to r0. */
     msr  psp, r0                            /* This is now the new top of stack to use in the task. */
     isb

portable/ARMv8M/non_secure/portable/IAR/ARM_CM33_NTZ/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -51,6 +53,7 @@
 #define portARCH_NAME                    "Cortex-M33"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         0
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __root
 /*-----------------------------------------------------------*/
 

portable/ARMv8M/non_secure/portable/IAR/ARM_CM35P/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -51,6 +53,7 @@
 #define portARCH_NAME                    "Cortex-M35P"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         0
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __root
 /*-----------------------------------------------------------*/
 

portable/ARMv8M/non_secure/portable/IAR/ARM_CM55/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -56,6 +58,7 @@
 #define portARCH_NAME                    "Cortex-M55"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         1
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __root
 /*-----------------------------------------------------------*/
 

portable/ARMv8M/non_secure/portable/IAR/ARM_CM85/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -56,6 +58,7 @@
 #define portARCH_NAME                    "Cortex-M85"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         1
+#define portHAS_PACBTI_FEATURE           1
 #define portDONT_DISCARD                 __root
 /*-----------------------------------------------------------*/
 

portable/CMakeLists.txt

@@ -453,6 +453,12 @@ add_library(freertos_kernel_port OBJECT
         IAR/ARM_CM33_NTZ/non_secure/portasm.s
         IAR/ARM_CM33_NTZ/non_secure/mpu_wrappers_v2_asm.S>
 
+    $<$<STREQUAL:${FREERTOS_PORT},IAR_ARM_CM33_TFM>:
+        IAR/ARM_CM33_NTZ/non_secure/port.c
+        IAR/ARM_CM33_NTZ/non_secure/portasm.s
+        IAR/ARM_CM33_NTZ/non_secure/mpu_wrappers_v2_asm.S
+        ThirdParty/GCC/ARM_TFM/os_wrapper_freertos.c>
+
     $<$<STREQUAL:${FREERTOS_PORT},IAR_ARM_CM35P_NONSECURE>:
         IAR/ARM_CM35P/non_secure/port.c
         IAR/ARM_CM35P/non_secure/portasm.s
@@ -486,6 +492,12 @@ add_library(freertos_kernel_port OBJECT
         IAR/ARM_CM55_NTZ/non_secure/portasm.s
         IAR/ARM_CM55_NTZ/non_secure/mpu_wrappers_v2_asm.S>
 
+    $<$<STREQUAL:${FREERTOS_PORT},IAR_ARM_CM55_TFM>:
+        IAR/ARM_CM55_NTZ/non_secure/port.c
+        IAR/ARM_CM55_NTZ/non_secure/portasm.s
+        IAR/ARM_CM55_NTZ/non_secure/mpu_wrappers_v2_asm.S
+        ThirdParty/GCC/ARM_TFM/os_wrapper_freertos.c>
+
     $<$<STREQUAL:${FREERTOS_PORT},IAR_ARM_CM85_NONSECURE>:
         IAR/ARM_CM85/non_secure/port.c
         IAR/ARM_CM85/non_secure/portasm.s
@@ -502,6 +514,12 @@ add_library(freertos_kernel_port OBJECT
         IAR/ARM_CM85_NTZ/non_secure/portasm.s
         IAR/ARM_CM85_NTZ/non_secure/mpu_wrappers_v2_asm.S>
 
+        $<$<STREQUAL:${FREERTOS_PORT},IAR_ARM_CM85_TFM>:
+        IAR/ARM_CM85_NTZ/non_secure/port.c
+        IAR/ARM_CM85_NTZ/non_secure/portasm.s
+        IAR/ARM_CM85_NTZ/non_secure/mpu_wrappers_v2_asm.S
+        ThirdParty/GCC/ARM_TFM/os_wrapper_freertos.c>
+
     # ARMv7-R Ports for IAR EWARM
     $<$<STREQUAL:${FREERTOS_PORT},IAR_ARM_CRX_NOGIC>:
         IAR/ARM_CRx_No_GIC/port.c
@@ -755,13 +773,112 @@ if( FREERTOS_PORT MATCHES "GCC_ARM_CM(3|4)_MPU" OR
     FREERTOS_PORT MATCHES "GCC_ARM_CM(23|33|55|85)_NONSECURE" OR
     FREERTOS_PORT MATCHES "GCC_ARM_CM(33|55|85)_TFM" OR
     FREERTOS_PORT MATCHES "IAR_ARM_CM(23|33|55|85)_NTZ_NONSECURE" OR
-    FREERTOS_PORT MATCHES "IAR_ARM_CM(23|33|55|85)_NONSECURE"
+    FREERTOS_PORT MATCHES "IAR_ARM_CM(23|33|55|85)_NONSECURE" OR
+    FREERTOS_PORT MATCHES "IAR_ARM_CM(33|55|85)_TFM"
 )
     target_sources(freertos_kernel_port PRIVATE
         Common/mpu_wrappers.c
         Common/mpu_wrappers_v2.c
     )
 endif()
+
+if (DEFINED FREERTOS_ARM_V_8_1_M_PACBTI_CONFIG )
+
+    if(${CMAKE_C_COMPILER_ID} STREQUAL "GNU")
+        message(FATAL_ERROR "ARMv8.1-M PACBTI support in the kernel is not yet enabled for GNU toolchain due to known issues.")
+    endif()
+
+    if(FREERTOS_PORT MATCHES ".*ARM_CM85")
+        if(FREERTOS_ARM_V_8_1_M_PACBTI_CONFIG STREQUAL "ARM_V_8_1_M_PACBTI_CONFIG_STANDARD")
+            target_compile_options(freertos_kernel_port PUBLIC $<$<STREQUAL:${CMAKE_C_COMPILER_ID},ARMClang>:-mbranch-protection=standard>)
+            target_compile_options(freertos_kernel_port PUBLIC $<$<STREQUAL:${CMAKE_C_COMPILER_ID},IAR>:$<$<COMPILE_LANGUAGE:C,CXX>:--branch_protection=bti+pac-ret>>)
+            target_compile_definitions(freertos_config
+                INTERFACE
+                    configENABLE_PAC=1
+                    configENABLE_BTI=1
+            )
+        elseif(FREERTOS_ARM_V_8_1_M_PACBTI_CONFIG STREQUAL "ARM_V_8_1_M_PACBTI_CONFIG_PACRET_LEAF_BTI")
+            if(${CMAKE_C_COMPILER_ID} STREQUAL "ARMClang")
+                target_compile_options(freertos_kernel_port
+                    PUBLIC
+                        -mbranch-protection=bti+pac-ret+leaf
+                )
+                target_compile_definitions(freertos_config
+                    PUBLIC
+                        configENABLE_PAC=1
+                        configENABLE_BTI=1
+                )
+            elseif(${CMAKE_C_COMPILER_ID} STREQUAL "IAR")
+                message(FATAL_ERROR "ARM_V_8_1_M_PACBTI_CONFIG_PACRET_LEAF_BTI PACBTI option is not supported on IAR Compiler.")
+            endif()
+        elseif(FREERTOS_ARM_V_8_1_M_PACBTI_CONFIG STREQUAL "ARM_V_8_1_M_PACBTI_CONFIG_PACRET")
+            target_compile_options(freertos_kernel_port PUBLIC $<$<STREQUAL:${CMAKE_C_COMPILER_ID},ARMClang>:-mbranch-protection=pac-ret>)
+            target_compile_options(freertos_kernel_port PUBLIC $<$<STREQUAL:${CMAKE_C_COMPILER_ID},IAR>:$<$<COMPILE_LANGUAGE:C,CXX>:--branch_protection=pac-ret>>)
+            target_compile_definitions(freertos_config
+                PUBLIC
+                    configENABLE_PAC=1
+            )
+        elseif(FREERTOS_ARM_V_8_1_M_PACBTI_CONFIG STREQUAL "ARM_V_8_1_M_PACBTI_CONFIG_PACRET_LEAF")
+            if(${CMAKE_C_COMPILER_ID} STREQUAL "ARMClang")
+                target_compile_options(freertos_kernel_port
+                    PUBLIC
+                        -mbranch-protection=pac-ret+leaf
+                )
+                target_compile_definitions(freertos_config
+                    PUBLIC
+                        configENABLE_PAC=1
+                )
+            elseif(${CMAKE_C_COMPILER_ID} STREQUAL "IAR")
+                message(FATAL_ERROR "ARM_V_8_1_M_PACBTI_CONFIG_PACRET_LEAF PACBTI option is not supported on IAR Compiler.")
+            endif()
+        elseif(FREERTOS_ARM_V_8_1_M_PACBTI_CONFIG STREQUAL "ARM_V_8_1_M_PACBTI_CONFIG_BTI")
+            target_compile_options(freertos_kernel_port PUBLIC $<$<STREQUAL:${CMAKE_C_COMPILER_ID},ARMClang>:-mbranch-protection=bti>)
+            target_compile_options(freertos_kernel_port PUBLIC $<$<STREQUAL:${CMAKE_C_COMPILER_ID},IAR>:$<$<COMPILE_LANGUAGE:C,CXX>:--branch_protection=bti>>)
+            target_compile_definitions(freertos_config
+                PUBLIC
+                    configENABLE_BTI=1
+            )
+        elseif(FREERTOS_ARM_V_8_1_M_PACBTI_CONFIG STREQUAL "ARM_V_8_1_M_PACBTI_CONFIG_NONE")
+            if(${CMAKE_C_COMPILER_ID} STREQUAL "ARMClang")
+                target_compile_options(freertos_kernel_port
+                    PUBLIC
+                        -mbranch-protection=none
+                )
+            endif()
+            target_compile_definitions(freertos_config
+                PUBLIC
+                    configENABLE_PAC=0
+                    configENABLE_BTI=0
+            )
+        else()
+            message(FATAL_ERROR "Invalid FREERTOS_ARM_V_8_1_M_PACBTI_CONFIG configuration, the supported configurations are
+            ARM_V_8_1_M_PACBTI_CONFIG_STANDARD,
+            ARM_V_8_1_M_PACBTI_CONFIG_PACRET_LEAF_BTI,
+            ARM_V_8_1_M_PACBTI_CONFIG_PACRET,
+            ARM_V_8_1_M_PACBTI_CONFIG_PACRET_LEAF,
+            ARM_V_8_1_M_PACBTI_CONFIG_BTI,
+            ARM_V_8_1_M_PACBTI_CONFIG_NONE
+            ")
+        endif()
+        if(NOT FREERTOS_ARM_V_8_1_M_PACBTI_CONFIG STREQUAL "ARM_V_8_1_M_PACBTI_CONFIG_NONE")
+            # The reason why `--library_security=pacbti-m` link option is defined for both `freertos_kernel_port`, and
+            # `freertos_kernel` targets even though `freertos_kernel_port` gets linked to `freertos_kernel` is that the
+            # `freertos_kernel_port` is an object library where its linker options don't propagate to the targets that
+            # link against it.
+            target_link_options(freertos_kernel_port
+                PUBLIC
+                    --library_security=pacbti-m
+            )
+            target_link_options(freertos_kernel
+                PUBLIC
+                    --library_security=pacbti-m
+            )
+        endif()
+    else()
+        message(FATAL_ERROR "FREERTOS_ARM_V_8_1_M_PACBTI_CONFIG option is currently only supported on ARM Cortex-M85 FreeRTOS port.")
+    endif()
+endif()
+
 add_library(freertos_kernel_port_headers INTERFACE)
 
 target_include_directories(freertos_kernel_port_headers INTERFACE
@@ -956,6 +1073,7 @@ target_include_directories(freertos_kernel_port_headers INTERFACE
     $<$<STREQUAL:${FREERTOS_PORT},IAR_ARM_CM33_NONSECURE>:${CMAKE_CURRENT_LIST_DIR}/IAR/ARM_CM33/non_secure>
     $<$<STREQUAL:${FREERTOS_PORT},IAR_ARM_CM33_SECURE>:${CMAKE_CURRENT_LIST_DIR}/IAR/ARM_CM33/secure>
     $<$<STREQUAL:${FREERTOS_PORT},IAR_ARM_CM33_NTZ_NONSECURE>:${CMAKE_CURRENT_LIST_DIR}/IAR/ARM_CM33_NTZ/non_secure>
+    $<$<STREQUAL:${FREERTOS_PORT},IAR_ARM_CM33_TFM>:${CMAKE_CURRENT_LIST_DIR}/IAR/ARM_CM33_NTZ/non_secure>
 
     $<$<STREQUAL:${FREERTOS_PORT},IAR_ARM_CM35P_NONSECURE>:${CMAKE_CURRENT_LIST_DIR}/IAR/ARM_CM35P/non_secure>
     $<$<STREQUAL:${FREERTOS_PORT},IAR_ARM_CM35P_SECURE>:${CMAKE_CURRENT_LIST_DIR}/IAR/ARM_CM35P/secure>
@@ -965,10 +1083,12 @@ target_include_directories(freertos_kernel_port_headers INTERFACE
     $<$<STREQUAL:${FREERTOS_PORT},IAR_ARM_CM55_NONSECURE>:${CMAKE_CURRENT_LIST_DIR}/IAR/ARM_CM55/non_secure>
     $<$<STREQUAL:${FREERTOS_PORT},IAR_ARM_CM55_SECURE>:${CMAKE_CURRENT_LIST_DIR}/IAR/ARM_CM55/secure>
     $<$<STREQUAL:${FREERTOS_PORT},IAR_ARM_CM55_NTZ_NONSECURE>:${CMAKE_CURRENT_LIST_DIR}/IAR/ARM_CM55_NTZ/non_secure>
+    $<$<STREQUAL:${FREERTOS_PORT},IAR_ARM_CM55_TFM>:${CMAKE_CURRENT_LIST_DIR}/IAR/ARM_CM55_NTZ/non_secure>
 
     $<$<STREQUAL:${FREERTOS_PORT},IAR_ARM_CM85_NONSECURE>:${CMAKE_CURRENT_LIST_DIR}/IAR/ARM_CM85/non_secure>
     $<$<STREQUAL:${FREERTOS_PORT},IAR_ARM_CM85_SECURE>:${CMAKE_CURRENT_LIST_DIR}/IAR/ARM_CM85/secure>
     $<$<STREQUAL:${FREERTOS_PORT},IAR_ARM_CM85_NTZ_NONSECURE>:${CMAKE_CURRENT_LIST_DIR}/IAR/ARM_CM85_NTZ/non_secure>
+    $<$<STREQUAL:${FREERTOS_PORT},IAR_ARM_CM85_TFM>:${CMAKE_CURRENT_LIST_DIR}/IAR/ARM_CM85_NTZ/non_secure>
 
     # ARMv7-R Ports for IAR EWARM
     $<$<STREQUAL:${FREERTOS_PORT},IAR_ARM_CRX_NOGIC>:${CMAKE_CURRENT_LIST_DIR}/IAR/ARM_CRx_No_GIC>

portable/GCC/ARM_CM23/non_secure/port.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -110,6 +112,7 @@ typedef void ( * portISR_t )( void );
 #define portSCB_VTOR_REG                      ( *( ( portISR_t ** ) 0xe000ed08 ) )
 #define portSCB_SYS_HANDLER_CTRL_STATE_REG    ( *( ( volatile uint32_t * ) 0xe000ed24 ) )
 #define portSCB_MEM_FAULT_ENABLE_BIT          ( 1UL << 16UL )
+#define portSCB_USG_FAULT_ENABLE_BIT          ( 1UL << 18UL )
 /*-----------------------------------------------------------*/
 
 /**
@@ -373,6 +376,20 @@ typedef void ( * portISR_t )( void );
  * any secure calls.
  */
 #define portNO_SECURE_CONTEXT    0
+
+/**
+ * @brief Constants required to check and configure PACBTI security feature implementation.
+ */
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    #define portID_ISAR5_REG         ( *( ( volatile uint32_t * ) 0xe000ed74 ) )
+
+    #define portCONTROL_UPAC_EN      ( 1UL << 7UL )
+    #define portCONTROL_PAC_EN       ( 1UL << 6UL )
+    #define portCONTROL_UBTI_EN      ( 1UL << 5UL )
+    #define portCONTROL_BTI_EN       ( 1UL << 4UL )
+
+#endif /* portHAS_PACBTI_FEATURE */
 /*-----------------------------------------------------------*/
 
 /**
@@ -410,6 +427,26 @@ static void prvTaskExitError( void );
     static void prvSetupFPU( void ) PRIVILEGED_FUNCTION;
 #endif /* configENABLE_FPU */
 
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+/**
+ * @brief Configures PACBTI features.
+ *
+ * This function configures the Pointer Authentication, and Branch Target
+ * Identification security features as per the user configuration. It returns
+ * the value of the special purpose CONTROL register accordingly, and optionally
+ * updates the CONTROL register value. Currently, only Cortex-M85 (ARMv8.1-M
+ * architecture based) target supports PACBTI security feature.
+ *
+ * @param xWriteControlRegister Used to control whether the special purpose
+ * CONTROL register should be updated or not.
+ *
+ * @return CONTROL register value according to the configured PACBTI option.
+ */
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister );
+
+#endif /* portHAS_PACBTI_FEATURE */
+
 /**
  * @brief Setup the timer to generate the tick interrupts.
  *
@@ -1457,6 +1494,7 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
                                          xMPU_SETTINGS * xMPUSettings ) /* PRIVILEGED_FUNCTION */
     {
         uint32_t ulIndex = 0;
+        uint32_t ulControl = 0x0;
 
         xMPUSettings->ulContext[ ulIndex ] = 0x04040404; /* r4. */
         ulIndex++;
@@ -1503,16 +1541,24 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
         xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) pxEndOfStack;         /* PSPLIM. */
         ulIndex++;
 
+        #if ( portHAS_PACBTI_FEATURE == 1 )
+        {
+            /* Check PACBTI security feature configuration before pushing the
+             * CONTROL register's value on task's TCB. */
+            ulControl = prvConfigurePACBTI( pdFALSE );
+        }
+        #endif /* portHAS_PACBTI_FEATURE */
+
         if( xRunPrivileged == pdTRUE )
         {
             xMPUSettings->ulTaskFlags |= portTASK_IS_PRIVILEGED_FLAG;
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
         else
         {
             xMPUSettings->ulTaskFlags &= ( ~portTASK_IS_PRIVILEGED_FLAG );
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
 
@@ -1740,6 +1786,14 @@ BaseType_t xPortStartScheduler( void ) /* PRIVILEGED_FUNCTION */
     portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
     portNVIC_SHPR2_REG = 0;
 
+    #if ( portHAS_PACBTI_FEATURE == 1 )
+    {
+        /* Set the CONTROL register value based on PACBTI security feature
+         * configuration before starting the first task. */
+        ( void) prvConfigurePACBTI( pdTRUE );
+    }
+    #endif /* portHAS_PACBTI_FEATURE */
+
     #if ( configENABLE_MPU == 1 )
     {
         /* Setup the Memory Protection Unit (MPU). */
@@ -2158,3 +2212,42 @@ BaseType_t xPortIsInsideInterrupt( void )
 
 #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */
 /*-----------------------------------------------------------*/
+
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister )
+    {
+        uint32_t ulControl = 0x0;
+
+        /* Ensure that PACBTI is implemented. */
+        configASSERT( portID_ISAR5_REG != 0x0 );
+
+        /* Enable UsageFault exception if PAC or BTI is enabled. */
+        #if( ( configENABLE_PAC == 1 ) || ( configENABLE_BTI == 1 ) )
+        {
+            portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_USG_FAULT_ENABLE_BIT;
+        }
+        #endif
+
+        #if( configENABLE_PAC == 1 )
+        {
+            ulControl |= ( portCONTROL_UPAC_EN | portCONTROL_PAC_EN );
+        }
+        #endif
+
+        #if( configENABLE_BTI == 1 )
+        {
+            ulControl |= ( portCONTROL_UBTI_EN | portCONTROL_BTI_EN );
+        }
+        #endif
+
+        if( xWriteControlRegister == pdTRUE )
+        {
+            __asm volatile ( "msr control, %0" : : "r" ( ulControl ) );
+        }
+
+        return ulControl;
+    }
+
+#endif /* #if ( portHAS_PACBTI_FEATURE == 1 ) */
+/*-----------------------------------------------------------*/

portable/GCC/ARM_CM23/non_secure/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -51,6 +53,7 @@
 #define portARCH_NAME                    "Cortex-M23"
 #define portHAS_ARMV8M_MAIN_EXTENSION    0
 #define portARMV8M_MINOR_VERSION         0
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __attribute__( ( used ) )
 /*-----------------------------------------------------------*/
 

portable/GCC/ARM_CM23_NTZ/non_secure/port.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -110,6 +112,7 @@ typedef void ( * portISR_t )( void );
 #define portSCB_VTOR_REG                      ( *( ( portISR_t ** ) 0xe000ed08 ) )
 #define portSCB_SYS_HANDLER_CTRL_STATE_REG    ( *( ( volatile uint32_t * ) 0xe000ed24 ) )
 #define portSCB_MEM_FAULT_ENABLE_BIT          ( 1UL << 16UL )
+#define portSCB_USG_FAULT_ENABLE_BIT          ( 1UL << 18UL )
 /*-----------------------------------------------------------*/
 
 /**
@@ -373,6 +376,20 @@ typedef void ( * portISR_t )( void );
  * any secure calls.
  */
 #define portNO_SECURE_CONTEXT    0
+
+/**
+ * @brief Constants required to check and configure PACBTI security feature implementation.
+ */
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    #define portID_ISAR5_REG         ( *( ( volatile uint32_t * ) 0xe000ed74 ) )
+
+    #define portCONTROL_UPAC_EN      ( 1UL << 7UL )
+    #define portCONTROL_PAC_EN       ( 1UL << 6UL )
+    #define portCONTROL_UBTI_EN      ( 1UL << 5UL )
+    #define portCONTROL_BTI_EN       ( 1UL << 4UL )
+
+#endif /* portHAS_PACBTI_FEATURE */
 /*-----------------------------------------------------------*/
 
 /**
@@ -410,6 +427,26 @@ static void prvTaskExitError( void );
     static void prvSetupFPU( void ) PRIVILEGED_FUNCTION;
 #endif /* configENABLE_FPU */
 
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+/**
+ * @brief Configures PACBTI features.
+ *
+ * This function configures the Pointer Authentication, and Branch Target
+ * Identification security features as per the user configuration. It returns
+ * the value of the special purpose CONTROL register accordingly, and optionally
+ * updates the CONTROL register value. Currently, only Cortex-M85 (ARMv8.1-M
+ * architecture based) target supports PACBTI security feature.
+ *
+ * @param xWriteControlRegister Used to control whether the special purpose
+ * CONTROL register should be updated or not.
+ *
+ * @return CONTROL register value according to the configured PACBTI option.
+ */
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister );
+
+#endif /* portHAS_PACBTI_FEATURE */
+
 /**
  * @brief Setup the timer to generate the tick interrupts.
  *
@@ -1457,6 +1494,7 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
                                          xMPU_SETTINGS * xMPUSettings ) /* PRIVILEGED_FUNCTION */
     {
         uint32_t ulIndex = 0;
+        uint32_t ulControl = 0x0;
 
         xMPUSettings->ulContext[ ulIndex ] = 0x04040404; /* r4. */
         ulIndex++;
@@ -1503,16 +1541,24 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
         xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) pxEndOfStack;         /* PSPLIM. */
         ulIndex++;
 
+        #if ( portHAS_PACBTI_FEATURE == 1 )
+        {
+            /* Check PACBTI security feature configuration before pushing the
+             * CONTROL register's value on task's TCB. */
+            ulControl = prvConfigurePACBTI( pdFALSE );
+        }
+        #endif /* portHAS_PACBTI_FEATURE */
+
         if( xRunPrivileged == pdTRUE )
         {
             xMPUSettings->ulTaskFlags |= portTASK_IS_PRIVILEGED_FLAG;
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
         else
         {
             xMPUSettings->ulTaskFlags &= ( ~portTASK_IS_PRIVILEGED_FLAG );
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
 
@@ -1740,6 +1786,14 @@ BaseType_t xPortStartScheduler( void ) /* PRIVILEGED_FUNCTION */
     portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
     portNVIC_SHPR2_REG = 0;
 
+    #if ( portHAS_PACBTI_FEATURE == 1 )
+    {
+        /* Set the CONTROL register value based on PACBTI security feature
+         * configuration before starting the first task. */
+        ( void) prvConfigurePACBTI( pdTRUE );
+    }
+    #endif /* portHAS_PACBTI_FEATURE */
+
     #if ( configENABLE_MPU == 1 )
     {
         /* Setup the Memory Protection Unit (MPU). */
@@ -2158,3 +2212,42 @@ BaseType_t xPortIsInsideInterrupt( void )
 
 #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */
 /*-----------------------------------------------------------*/
+
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister )
+    {
+        uint32_t ulControl = 0x0;
+
+        /* Ensure that PACBTI is implemented. */
+        configASSERT( portID_ISAR5_REG != 0x0 );
+
+        /* Enable UsageFault exception if PAC or BTI is enabled. */
+        #if( ( configENABLE_PAC == 1 ) || ( configENABLE_BTI == 1 ) )
+        {
+            portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_USG_FAULT_ENABLE_BIT;
+        }
+        #endif
+
+        #if( configENABLE_PAC == 1 )
+        {
+            ulControl |= ( portCONTROL_UPAC_EN | portCONTROL_PAC_EN );
+        }
+        #endif
+
+        #if( configENABLE_BTI == 1 )
+        {
+            ulControl |= ( portCONTROL_UBTI_EN | portCONTROL_BTI_EN );
+        }
+        #endif
+
+        if( xWriteControlRegister == pdTRUE )
+        {
+            __asm volatile ( "msr control, %0" : : "r" ( ulControl ) );
+        }
+
+        return ulControl;
+    }
+
+#endif /* #if ( portHAS_PACBTI_FEATURE == 1 ) */
+/*-----------------------------------------------------------*/

portable/GCC/ARM_CM23_NTZ/non_secure/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -51,6 +53,7 @@
 #define portARCH_NAME                    "Cortex-M23"
 #define portHAS_ARMV8M_MAIN_EXTENSION    0
 #define portARMV8M_MINOR_VERSION         0
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __attribute__( ( used ) )
 /*-----------------------------------------------------------*/
 

portable/GCC/ARM_CM33/non_secure/port.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -110,6 +112,7 @@ typedef void ( * portISR_t )( void );
 #define portSCB_VTOR_REG                      ( *( ( portISR_t ** ) 0xe000ed08 ) )
 #define portSCB_SYS_HANDLER_CTRL_STATE_REG    ( *( ( volatile uint32_t * ) 0xe000ed24 ) )
 #define portSCB_MEM_FAULT_ENABLE_BIT          ( 1UL << 16UL )
+#define portSCB_USG_FAULT_ENABLE_BIT          ( 1UL << 18UL )
 /*-----------------------------------------------------------*/
 
 /**
@@ -373,6 +376,20 @@ typedef void ( * portISR_t )( void );
  * any secure calls.
  */
 #define portNO_SECURE_CONTEXT    0
+
+/**
+ * @brief Constants required to check and configure PACBTI security feature implementation.
+ */
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    #define portID_ISAR5_REG         ( *( ( volatile uint32_t * ) 0xe000ed74 ) )
+
+    #define portCONTROL_UPAC_EN      ( 1UL << 7UL )
+    #define portCONTROL_PAC_EN       ( 1UL << 6UL )
+    #define portCONTROL_UBTI_EN      ( 1UL << 5UL )
+    #define portCONTROL_BTI_EN       ( 1UL << 4UL )
+
+#endif /* portHAS_PACBTI_FEATURE */
 /*-----------------------------------------------------------*/
 
 /**
@@ -410,6 +427,26 @@ static void prvTaskExitError( void );
     static void prvSetupFPU( void ) PRIVILEGED_FUNCTION;
 #endif /* configENABLE_FPU */
 
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+/**
+ * @brief Configures PACBTI features.
+ *
+ * This function configures the Pointer Authentication, and Branch Target
+ * Identification security features as per the user configuration. It returns
+ * the value of the special purpose CONTROL register accordingly, and optionally
+ * updates the CONTROL register value. Currently, only Cortex-M85 (ARMv8.1-M
+ * architecture based) target supports PACBTI security feature.
+ *
+ * @param xWriteControlRegister Used to control whether the special purpose
+ * CONTROL register should be updated or not.
+ *
+ * @return CONTROL register value according to the configured PACBTI option.
+ */
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister );
+
+#endif /* portHAS_PACBTI_FEATURE */
+
 /**
  * @brief Setup the timer to generate the tick interrupts.
  *
@@ -1457,6 +1494,7 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
                                          xMPU_SETTINGS * xMPUSettings ) /* PRIVILEGED_FUNCTION */
     {
         uint32_t ulIndex = 0;
+        uint32_t ulControl = 0x0;
 
         xMPUSettings->ulContext[ ulIndex ] = 0x04040404; /* r4. */
         ulIndex++;
@@ -1503,16 +1541,24 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
         xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) pxEndOfStack;         /* PSPLIM. */
         ulIndex++;
 
+        #if ( portHAS_PACBTI_FEATURE == 1 )
+        {
+            /* Check PACBTI security feature configuration before pushing the
+             * CONTROL register's value on task's TCB. */
+            ulControl = prvConfigurePACBTI( pdFALSE );
+        }
+        #endif /* portHAS_PACBTI_FEATURE */
+
         if( xRunPrivileged == pdTRUE )
         {
             xMPUSettings->ulTaskFlags |= portTASK_IS_PRIVILEGED_FLAG;
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
         else
         {
             xMPUSettings->ulTaskFlags &= ( ~portTASK_IS_PRIVILEGED_FLAG );
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
 
@@ -1740,6 +1786,14 @@ BaseType_t xPortStartScheduler( void ) /* PRIVILEGED_FUNCTION */
     portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
     portNVIC_SHPR2_REG = 0;
 
+    #if ( portHAS_PACBTI_FEATURE == 1 )
+    {
+        /* Set the CONTROL register value based on PACBTI security feature
+         * configuration before starting the first task. */
+        ( void) prvConfigurePACBTI( pdTRUE );
+    }
+    #endif /* portHAS_PACBTI_FEATURE */
+
     #if ( configENABLE_MPU == 1 )
     {
         /* Setup the Memory Protection Unit (MPU). */
@@ -2158,3 +2212,42 @@ BaseType_t xPortIsInsideInterrupt( void )
 
 #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */
 /*-----------------------------------------------------------*/
+
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister )
+    {
+        uint32_t ulControl = 0x0;
+
+        /* Ensure that PACBTI is implemented. */
+        configASSERT( portID_ISAR5_REG != 0x0 );
+
+        /* Enable UsageFault exception if PAC or BTI is enabled. */
+        #if( ( configENABLE_PAC == 1 ) || ( configENABLE_BTI == 1 ) )
+        {
+            portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_USG_FAULT_ENABLE_BIT;
+        }
+        #endif
+
+        #if( configENABLE_PAC == 1 )
+        {
+            ulControl |= ( portCONTROL_UPAC_EN | portCONTROL_PAC_EN );
+        }
+        #endif
+
+        #if( configENABLE_BTI == 1 )
+        {
+            ulControl |= ( portCONTROL_UBTI_EN | portCONTROL_BTI_EN );
+        }
+        #endif
+
+        if( xWriteControlRegister == pdTRUE )
+        {
+            __asm volatile ( "msr control, %0" : : "r" ( ulControl ) );
+        }
+
+        return ulControl;
+    }
+
+#endif /* #if ( portHAS_PACBTI_FEATURE == 1 ) */
+/*-----------------------------------------------------------*/

portable/GCC/ARM_CM33/non_secure/portasm.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -134,8 +136,9 @@
             "   ldr  r4, =xSecureContext                        \n"
             "   str  r1, [r4]                                   \n" /* Set xSecureContext to this task's value for the same. */
             "   msr  psplim, r2                                 \n" /* Set this task's PSPLIM value. */
-            "   movs r1, #2                                     \n" /* r1 = 2. */
+            "   mrs  r1, control                                \n" /* Obtain current control register value. */
-            "   msr  CONTROL, r1                                \n" /* Switch to use PSP in the thread mode. */
+            "   orrs r1, r1, #2                                 \n" /* r1 = r1 | 0x2 - Set the second bit to use the program stack pointer (PSP). */
+            "   msr control, r1                                 \n" /* Write back the new control register value. */
             "   adds r0, #32                                    \n" /* Discard everything up to r0. */
             "   msr  psp, r0                                    \n" /* This is now the new top of stack to use in the task. */
             "   isb                                             \n"

portable/GCC/ARM_CM33/non_secure/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -51,6 +53,7 @@
 #define portARCH_NAME                    "Cortex-M33"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         0
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __attribute__( ( used ) )
 /*-----------------------------------------------------------*/
 

portable/GCC/ARM_CM33_NTZ/non_secure/port.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -110,6 +112,7 @@ typedef void ( * portISR_t )( void );
 #define portSCB_VTOR_REG                      ( *( ( portISR_t ** ) 0xe000ed08 ) )
 #define portSCB_SYS_HANDLER_CTRL_STATE_REG    ( *( ( volatile uint32_t * ) 0xe000ed24 ) )
 #define portSCB_MEM_FAULT_ENABLE_BIT          ( 1UL << 16UL )
+#define portSCB_USG_FAULT_ENABLE_BIT          ( 1UL << 18UL )
 /*-----------------------------------------------------------*/
 
 /**
@@ -373,6 +376,20 @@ typedef void ( * portISR_t )( void );
  * any secure calls.
  */
 #define portNO_SECURE_CONTEXT    0
+
+/**
+ * @brief Constants required to check and configure PACBTI security feature implementation.
+ */
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    #define portID_ISAR5_REG         ( *( ( volatile uint32_t * ) 0xe000ed74 ) )
+
+    #define portCONTROL_UPAC_EN      ( 1UL << 7UL )
+    #define portCONTROL_PAC_EN       ( 1UL << 6UL )
+    #define portCONTROL_UBTI_EN      ( 1UL << 5UL )
+    #define portCONTROL_BTI_EN       ( 1UL << 4UL )
+
+#endif /* portHAS_PACBTI_FEATURE */
 /*-----------------------------------------------------------*/
 
 /**
@@ -410,6 +427,26 @@ static void prvTaskExitError( void );
     static void prvSetupFPU( void ) PRIVILEGED_FUNCTION;
 #endif /* configENABLE_FPU */
 
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+/**
+ * @brief Configures PACBTI features.
+ *
+ * This function configures the Pointer Authentication, and Branch Target
+ * Identification security features as per the user configuration. It returns
+ * the value of the special purpose CONTROL register accordingly, and optionally
+ * updates the CONTROL register value. Currently, only Cortex-M85 (ARMv8.1-M
+ * architecture based) target supports PACBTI security feature.
+ *
+ * @param xWriteControlRegister Used to control whether the special purpose
+ * CONTROL register should be updated or not.
+ *
+ * @return CONTROL register value according to the configured PACBTI option.
+ */
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister );
+
+#endif /* portHAS_PACBTI_FEATURE */
+
 /**
  * @brief Setup the timer to generate the tick interrupts.
  *
@@ -1457,6 +1494,7 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
                                          xMPU_SETTINGS * xMPUSettings ) /* PRIVILEGED_FUNCTION */
     {
         uint32_t ulIndex = 0;
+        uint32_t ulControl = 0x0;
 
         xMPUSettings->ulContext[ ulIndex ] = 0x04040404; /* r4. */
         ulIndex++;
@@ -1503,16 +1541,24 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
         xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) pxEndOfStack;         /* PSPLIM. */
         ulIndex++;
 
+        #if ( portHAS_PACBTI_FEATURE == 1 )
+        {
+            /* Check PACBTI security feature configuration before pushing the
+             * CONTROL register's value on task's TCB. */
+            ulControl = prvConfigurePACBTI( pdFALSE );
+        }
+        #endif /* portHAS_PACBTI_FEATURE */
+
         if( xRunPrivileged == pdTRUE )
         {
             xMPUSettings->ulTaskFlags |= portTASK_IS_PRIVILEGED_FLAG;
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
         else
         {
             xMPUSettings->ulTaskFlags &= ( ~portTASK_IS_PRIVILEGED_FLAG );
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
 
@@ -1740,6 +1786,14 @@ BaseType_t xPortStartScheduler( void ) /* PRIVILEGED_FUNCTION */
     portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
     portNVIC_SHPR2_REG = 0;
 
+    #if ( portHAS_PACBTI_FEATURE == 1 )
+    {
+        /* Set the CONTROL register value based on PACBTI security feature
+         * configuration before starting the first task. */
+        ( void) prvConfigurePACBTI( pdTRUE );
+    }
+    #endif /* portHAS_PACBTI_FEATURE */
+
     #if ( configENABLE_MPU == 1 )
     {
         /* Setup the Memory Protection Unit (MPU). */
@@ -2158,3 +2212,42 @@ BaseType_t xPortIsInsideInterrupt( void )
 
 #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */
 /*-----------------------------------------------------------*/
+
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister )
+    {
+        uint32_t ulControl = 0x0;
+
+        /* Ensure that PACBTI is implemented. */
+        configASSERT( portID_ISAR5_REG != 0x0 );
+
+        /* Enable UsageFault exception if PAC or BTI is enabled. */
+        #if( ( configENABLE_PAC == 1 ) || ( configENABLE_BTI == 1 ) )
+        {
+            portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_USG_FAULT_ENABLE_BIT;
+        }
+        #endif
+
+        #if( configENABLE_PAC == 1 )
+        {
+            ulControl |= ( portCONTROL_UPAC_EN | portCONTROL_PAC_EN );
+        }
+        #endif
+
+        #if( configENABLE_BTI == 1 )
+        {
+            ulControl |= ( portCONTROL_UBTI_EN | portCONTROL_BTI_EN );
+        }
+        #endif
+
+        if( xWriteControlRegister == pdTRUE )
+        {
+            __asm volatile ( "msr control, %0" : : "r" ( ulControl ) );
+        }
+
+        return ulControl;
+    }
+
+#endif /* #if ( portHAS_PACBTI_FEATURE == 1 ) */
+/*-----------------------------------------------------------*/

portable/GCC/ARM_CM33_NTZ/non_secure/portasm.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -130,8 +132,9 @@
             "                                                   \n"
             "   ldm  r0!, {r1-r2}                               \n" /* Read from stack - r1 = PSPLIM and r2 = EXC_RETURN. */
             "   msr  psplim, r1                                 \n" /* Set this task's PSPLIM value. */
-            "   movs r1, #2                                     \n" /* r1 = 2. */
+            "   mrs  r1, control                                \n" /* Obtain current control register value. */
-            "   msr  CONTROL, r1                                \n" /* Switch to use PSP in the thread mode. */
+            "   orrs r1, r1, #2                                 \n" /* r1 = r1 | 0x2 - Set the second bit to use the program stack pointer (PSP). */
+            "   msr control, r1                                 \n" /* Write back the new control register value. */
             "   adds r0, #32                                    \n" /* Discard everything up to r0. */
             "   msr  psp, r0                                    \n" /* This is now the new top of stack to use in the task. */
             "   isb                                             \n"

portable/GCC/ARM_CM33_NTZ/non_secure/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -51,6 +53,7 @@
 #define portARCH_NAME                    "Cortex-M33"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         0
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __attribute__( ( used ) )
 /*-----------------------------------------------------------*/
 

portable/GCC/ARM_CM35P/non_secure/port.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -110,6 +112,7 @@ typedef void ( * portISR_t )( void );
 #define portSCB_VTOR_REG                      ( *( ( portISR_t ** ) 0xe000ed08 ) )
 #define portSCB_SYS_HANDLER_CTRL_STATE_REG    ( *( ( volatile uint32_t * ) 0xe000ed24 ) )
 #define portSCB_MEM_FAULT_ENABLE_BIT          ( 1UL << 16UL )
+#define portSCB_USG_FAULT_ENABLE_BIT          ( 1UL << 18UL )
 /*-----------------------------------------------------------*/
 
 /**
@@ -373,6 +376,20 @@ typedef void ( * portISR_t )( void );
  * any secure calls.
  */
 #define portNO_SECURE_CONTEXT    0
+
+/**
+ * @brief Constants required to check and configure PACBTI security feature implementation.
+ */
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    #define portID_ISAR5_REG         ( *( ( volatile uint32_t * ) 0xe000ed74 ) )
+
+    #define portCONTROL_UPAC_EN      ( 1UL << 7UL )
+    #define portCONTROL_PAC_EN       ( 1UL << 6UL )
+    #define portCONTROL_UBTI_EN      ( 1UL << 5UL )
+    #define portCONTROL_BTI_EN       ( 1UL << 4UL )
+
+#endif /* portHAS_PACBTI_FEATURE */
 /*-----------------------------------------------------------*/
 
 /**
@@ -410,6 +427,26 @@ static void prvTaskExitError( void );
     static void prvSetupFPU( void ) PRIVILEGED_FUNCTION;
 #endif /* configENABLE_FPU */
 
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+/**
+ * @brief Configures PACBTI features.
+ *
+ * This function configures the Pointer Authentication, and Branch Target
+ * Identification security features as per the user configuration. It returns
+ * the value of the special purpose CONTROL register accordingly, and optionally
+ * updates the CONTROL register value. Currently, only Cortex-M85 (ARMv8.1-M
+ * architecture based) target supports PACBTI security feature.
+ *
+ * @param xWriteControlRegister Used to control whether the special purpose
+ * CONTROL register should be updated or not.
+ *
+ * @return CONTROL register value according to the configured PACBTI option.
+ */
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister );
+
+#endif /* portHAS_PACBTI_FEATURE */
+
 /**
  * @brief Setup the timer to generate the tick interrupts.
  *
@@ -1457,6 +1494,7 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
                                          xMPU_SETTINGS * xMPUSettings ) /* PRIVILEGED_FUNCTION */
     {
         uint32_t ulIndex = 0;
+        uint32_t ulControl = 0x0;
 
         xMPUSettings->ulContext[ ulIndex ] = 0x04040404; /* r4. */
         ulIndex++;
@@ -1503,16 +1541,24 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
         xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) pxEndOfStack;         /* PSPLIM. */
         ulIndex++;
 
+        #if ( portHAS_PACBTI_FEATURE == 1 )
+        {
+            /* Check PACBTI security feature configuration before pushing the
+             * CONTROL register's value on task's TCB. */
+            ulControl = prvConfigurePACBTI( pdFALSE );
+        }
+        #endif /* portHAS_PACBTI_FEATURE */
+
         if( xRunPrivileged == pdTRUE )
         {
             xMPUSettings->ulTaskFlags |= portTASK_IS_PRIVILEGED_FLAG;
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
         else
         {
             xMPUSettings->ulTaskFlags &= ( ~portTASK_IS_PRIVILEGED_FLAG );
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
 
@@ -1740,6 +1786,14 @@ BaseType_t xPortStartScheduler( void ) /* PRIVILEGED_FUNCTION */
     portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
     portNVIC_SHPR2_REG = 0;
 
+    #if ( portHAS_PACBTI_FEATURE == 1 )
+    {
+        /* Set the CONTROL register value based on PACBTI security feature
+         * configuration before starting the first task. */
+        ( void) prvConfigurePACBTI( pdTRUE );
+    }
+    #endif /* portHAS_PACBTI_FEATURE */
+
     #if ( configENABLE_MPU == 1 )
     {
         /* Setup the Memory Protection Unit (MPU). */
@@ -2158,3 +2212,42 @@ BaseType_t xPortIsInsideInterrupt( void )
 
 #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */
 /*-----------------------------------------------------------*/
+
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister )
+    {
+        uint32_t ulControl = 0x0;
+
+        /* Ensure that PACBTI is implemented. */
+        configASSERT( portID_ISAR5_REG != 0x0 );
+
+        /* Enable UsageFault exception if PAC or BTI is enabled. */
+        #if( ( configENABLE_PAC == 1 ) || ( configENABLE_BTI == 1 ) )
+        {
+            portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_USG_FAULT_ENABLE_BIT;
+        }
+        #endif
+
+        #if( configENABLE_PAC == 1 )
+        {
+            ulControl |= ( portCONTROL_UPAC_EN | portCONTROL_PAC_EN );
+        }
+        #endif
+
+        #if( configENABLE_BTI == 1 )
+        {
+            ulControl |= ( portCONTROL_UBTI_EN | portCONTROL_BTI_EN );
+        }
+        #endif
+
+        if( xWriteControlRegister == pdTRUE )
+        {
+            __asm volatile ( "msr control, %0" : : "r" ( ulControl ) );
+        }
+
+        return ulControl;
+    }
+
+#endif /* #if ( portHAS_PACBTI_FEATURE == 1 ) */
+/*-----------------------------------------------------------*/

portable/GCC/ARM_CM35P/non_secure/portasm.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -134,8 +136,9 @@
             "   ldr  r4, =xSecureContext                        \n"
             "   str  r1, [r4]                                   \n" /* Set xSecureContext to this task's value for the same. */
             "   msr  psplim, r2                                 \n" /* Set this task's PSPLIM value. */
-            "   movs r1, #2                                     \n" /* r1 = 2. */
+            "   mrs  r1, control                                \n" /* Obtain current control register value. */
-            "   msr  CONTROL, r1                                \n" /* Switch to use PSP in the thread mode. */
+            "   orrs r1, r1, #2                                 \n" /* r1 = r1 | 0x2 - Set the second bit to use the program stack pointer (PSP). */
+            "   msr control, r1                                 \n" /* Write back the new control register value. */
             "   adds r0, #32                                    \n" /* Discard everything up to r0. */
             "   msr  psp, r0                                    \n" /* This is now the new top of stack to use in the task. */
             "   isb                                             \n"

portable/GCC/ARM_CM35P/non_secure/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -51,6 +53,7 @@
 #define portARCH_NAME                    "Cortex-M35P"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         0
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __attribute__( ( used ) )
 /*-----------------------------------------------------------*/
 

portable/GCC/ARM_CM35P_NTZ/non_secure/port.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -110,6 +112,7 @@ typedef void ( * portISR_t )( void );
 #define portSCB_VTOR_REG                      ( *( ( portISR_t ** ) 0xe000ed08 ) )
 #define portSCB_SYS_HANDLER_CTRL_STATE_REG    ( *( ( volatile uint32_t * ) 0xe000ed24 ) )
 #define portSCB_MEM_FAULT_ENABLE_BIT          ( 1UL << 16UL )
+#define portSCB_USG_FAULT_ENABLE_BIT          ( 1UL << 18UL )
 /*-----------------------------------------------------------*/
 
 /**
@@ -373,6 +376,20 @@ typedef void ( * portISR_t )( void );
  * any secure calls.
  */
 #define portNO_SECURE_CONTEXT    0
+
+/**
+ * @brief Constants required to check and configure PACBTI security feature implementation.
+ */
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    #define portID_ISAR5_REG         ( *( ( volatile uint32_t * ) 0xe000ed74 ) )
+
+    #define portCONTROL_UPAC_EN      ( 1UL << 7UL )
+    #define portCONTROL_PAC_EN       ( 1UL << 6UL )
+    #define portCONTROL_UBTI_EN      ( 1UL << 5UL )
+    #define portCONTROL_BTI_EN       ( 1UL << 4UL )
+
+#endif /* portHAS_PACBTI_FEATURE */
 /*-----------------------------------------------------------*/
 
 /**
@@ -410,6 +427,26 @@ static void prvTaskExitError( void );
     static void prvSetupFPU( void ) PRIVILEGED_FUNCTION;
 #endif /* configENABLE_FPU */
 
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+/**
+ * @brief Configures PACBTI features.
+ *
+ * This function configures the Pointer Authentication, and Branch Target
+ * Identification security features as per the user configuration. It returns
+ * the value of the special purpose CONTROL register accordingly, and optionally
+ * updates the CONTROL register value. Currently, only Cortex-M85 (ARMv8.1-M
+ * architecture based) target supports PACBTI security feature.
+ *
+ * @param xWriteControlRegister Used to control whether the special purpose
+ * CONTROL register should be updated or not.
+ *
+ * @return CONTROL register value according to the configured PACBTI option.
+ */
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister );
+
+#endif /* portHAS_PACBTI_FEATURE */
+
 /**
  * @brief Setup the timer to generate the tick interrupts.
  *
@@ -1457,6 +1494,7 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
                                          xMPU_SETTINGS * xMPUSettings ) /* PRIVILEGED_FUNCTION */
     {
         uint32_t ulIndex = 0;
+        uint32_t ulControl = 0x0;
 
         xMPUSettings->ulContext[ ulIndex ] = 0x04040404; /* r4. */
         ulIndex++;
@@ -1503,16 +1541,24 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
         xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) pxEndOfStack;         /* PSPLIM. */
         ulIndex++;
 
+        #if ( portHAS_PACBTI_FEATURE == 1 )
+        {
+            /* Check PACBTI security feature configuration before pushing the
+             * CONTROL register's value on task's TCB. */
+            ulControl = prvConfigurePACBTI( pdFALSE );
+        }
+        #endif /* portHAS_PACBTI_FEATURE */
+
         if( xRunPrivileged == pdTRUE )
         {
             xMPUSettings->ulTaskFlags |= portTASK_IS_PRIVILEGED_FLAG;
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
         else
         {
             xMPUSettings->ulTaskFlags &= ( ~portTASK_IS_PRIVILEGED_FLAG );
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
 
@@ -1740,6 +1786,14 @@ BaseType_t xPortStartScheduler( void ) /* PRIVILEGED_FUNCTION */
     portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
     portNVIC_SHPR2_REG = 0;
 
+    #if ( portHAS_PACBTI_FEATURE == 1 )
+    {
+        /* Set the CONTROL register value based on PACBTI security feature
+         * configuration before starting the first task. */
+        ( void) prvConfigurePACBTI( pdTRUE );
+    }
+    #endif /* portHAS_PACBTI_FEATURE */
+
     #if ( configENABLE_MPU == 1 )
     {
         /* Setup the Memory Protection Unit (MPU). */
@@ -2158,3 +2212,42 @@ BaseType_t xPortIsInsideInterrupt( void )
 
 #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */
 /*-----------------------------------------------------------*/
+
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister )
+    {
+        uint32_t ulControl = 0x0;
+
+        /* Ensure that PACBTI is implemented. */
+        configASSERT( portID_ISAR5_REG != 0x0 );
+
+        /* Enable UsageFault exception if PAC or BTI is enabled. */
+        #if( ( configENABLE_PAC == 1 ) || ( configENABLE_BTI == 1 ) )
+        {
+            portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_USG_FAULT_ENABLE_BIT;
+        }
+        #endif
+
+        #if( configENABLE_PAC == 1 )
+        {
+            ulControl |= ( portCONTROL_UPAC_EN | portCONTROL_PAC_EN );
+        }
+        #endif
+
+        #if( configENABLE_BTI == 1 )
+        {
+            ulControl |= ( portCONTROL_UBTI_EN | portCONTROL_BTI_EN );
+        }
+        #endif
+
+        if( xWriteControlRegister == pdTRUE )
+        {
+            __asm volatile ( "msr control, %0" : : "r" ( ulControl ) );
+        }
+
+        return ulControl;
+    }
+
+#endif /* #if ( portHAS_PACBTI_FEATURE == 1 ) */
+/*-----------------------------------------------------------*/

portable/GCC/ARM_CM35P_NTZ/non_secure/portasm.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -130,8 +132,9 @@
             "                                                   \n"
             "   ldm  r0!, {r1-r2}                               \n" /* Read from stack - r1 = PSPLIM and r2 = EXC_RETURN. */
             "   msr  psplim, r1                                 \n" /* Set this task's PSPLIM value. */
-            "   movs r1, #2                                     \n" /* r1 = 2. */
+            "   mrs  r1, control                                \n" /* Obtain current control register value. */
-            "   msr  CONTROL, r1                                \n" /* Switch to use PSP in the thread mode. */
+            "   orrs r1, r1, #2                                 \n" /* r1 = r1 | 0x2 - Set the second bit to use the program stack pointer (PSP). */
+            "   msr control, r1                                 \n" /* Write back the new control register value. */
             "   adds r0, #32                                    \n" /* Discard everything up to r0. */
             "   msr  psp, r0                                    \n" /* This is now the new top of stack to use in the task. */
             "   isb                                             \n"

portable/GCC/ARM_CM35P_NTZ/non_secure/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -51,6 +53,7 @@
 #define portARCH_NAME                    "Cortex-M35P"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         0
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __attribute__( ( used ) )
 /*-----------------------------------------------------------*/
 

portable/GCC/ARM_CM55/non_secure/port.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -110,6 +112,7 @@ typedef void ( * portISR_t )( void );
 #define portSCB_VTOR_REG                      ( *( ( portISR_t ** ) 0xe000ed08 ) )
 #define portSCB_SYS_HANDLER_CTRL_STATE_REG    ( *( ( volatile uint32_t * ) 0xe000ed24 ) )
 #define portSCB_MEM_FAULT_ENABLE_BIT          ( 1UL << 16UL )
+#define portSCB_USG_FAULT_ENABLE_BIT          ( 1UL << 18UL )
 /*-----------------------------------------------------------*/
 
 /**
@@ -373,6 +376,20 @@ typedef void ( * portISR_t )( void );
  * any secure calls.
  */
 #define portNO_SECURE_CONTEXT    0
+
+/**
+ * @brief Constants required to check and configure PACBTI security feature implementation.
+ */
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    #define portID_ISAR5_REG         ( *( ( volatile uint32_t * ) 0xe000ed74 ) )
+
+    #define portCONTROL_UPAC_EN      ( 1UL << 7UL )
+    #define portCONTROL_PAC_EN       ( 1UL << 6UL )
+    #define portCONTROL_UBTI_EN      ( 1UL << 5UL )
+    #define portCONTROL_BTI_EN       ( 1UL << 4UL )
+
+#endif /* portHAS_PACBTI_FEATURE */
 /*-----------------------------------------------------------*/
 
 /**
@@ -410,6 +427,26 @@ static void prvTaskExitError( void );
     static void prvSetupFPU( void ) PRIVILEGED_FUNCTION;
 #endif /* configENABLE_FPU */
 
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+/**
+ * @brief Configures PACBTI features.
+ *
+ * This function configures the Pointer Authentication, and Branch Target
+ * Identification security features as per the user configuration. It returns
+ * the value of the special purpose CONTROL register accordingly, and optionally
+ * updates the CONTROL register value. Currently, only Cortex-M85 (ARMv8.1-M
+ * architecture based) target supports PACBTI security feature.
+ *
+ * @param xWriteControlRegister Used to control whether the special purpose
+ * CONTROL register should be updated or not.
+ *
+ * @return CONTROL register value according to the configured PACBTI option.
+ */
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister );
+
+#endif /* portHAS_PACBTI_FEATURE */
+
 /**
  * @brief Setup the timer to generate the tick interrupts.
  *
@@ -1457,6 +1494,7 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
                                          xMPU_SETTINGS * xMPUSettings ) /* PRIVILEGED_FUNCTION */
     {
         uint32_t ulIndex = 0;
+        uint32_t ulControl = 0x0;
 
         xMPUSettings->ulContext[ ulIndex ] = 0x04040404; /* r4. */
         ulIndex++;
@@ -1503,16 +1541,24 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
         xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) pxEndOfStack;         /* PSPLIM. */
         ulIndex++;
 
+        #if ( portHAS_PACBTI_FEATURE == 1 )
+        {
+            /* Check PACBTI security feature configuration before pushing the
+             * CONTROL register's value on task's TCB. */
+            ulControl = prvConfigurePACBTI( pdFALSE );
+        }
+        #endif /* portHAS_PACBTI_FEATURE */
+
         if( xRunPrivileged == pdTRUE )
         {
             xMPUSettings->ulTaskFlags |= portTASK_IS_PRIVILEGED_FLAG;
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
         else
         {
             xMPUSettings->ulTaskFlags &= ( ~portTASK_IS_PRIVILEGED_FLAG );
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
 
@@ -1740,6 +1786,14 @@ BaseType_t xPortStartScheduler( void ) /* PRIVILEGED_FUNCTION */
     portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
     portNVIC_SHPR2_REG = 0;
 
+    #if ( portHAS_PACBTI_FEATURE == 1 )
+    {
+        /* Set the CONTROL register value based on PACBTI security feature
+         * configuration before starting the first task. */
+        ( void) prvConfigurePACBTI( pdTRUE );
+    }
+    #endif /* portHAS_PACBTI_FEATURE */
+
     #if ( configENABLE_MPU == 1 )
     {
         /* Setup the Memory Protection Unit (MPU). */
@@ -2158,3 +2212,42 @@ BaseType_t xPortIsInsideInterrupt( void )
 
 #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */
 /*-----------------------------------------------------------*/
+
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister )
+    {
+        uint32_t ulControl = 0x0;
+
+        /* Ensure that PACBTI is implemented. */
+        configASSERT( portID_ISAR5_REG != 0x0 );
+
+        /* Enable UsageFault exception if PAC or BTI is enabled. */
+        #if( ( configENABLE_PAC == 1 ) || ( configENABLE_BTI == 1 ) )
+        {
+            portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_USG_FAULT_ENABLE_BIT;
+        }
+        #endif
+
+        #if( configENABLE_PAC == 1 )
+        {
+            ulControl |= ( portCONTROL_UPAC_EN | portCONTROL_PAC_EN );
+        }
+        #endif
+
+        #if( configENABLE_BTI == 1 )
+        {
+            ulControl |= ( portCONTROL_UBTI_EN | portCONTROL_BTI_EN );
+        }
+        #endif
+
+        if( xWriteControlRegister == pdTRUE )
+        {
+            __asm volatile ( "msr control, %0" : : "r" ( ulControl ) );
+        }
+
+        return ulControl;
+    }
+
+#endif /* #if ( portHAS_PACBTI_FEATURE == 1 ) */
+/*-----------------------------------------------------------*/

portable/GCC/ARM_CM55/non_secure/portasm.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -134,8 +136,9 @@
             "   ldr  r4, =xSecureContext                        \n"
             "   str  r1, [r4]                                   \n" /* Set xSecureContext to this task's value for the same. */
             "   msr  psplim, r2                                 \n" /* Set this task's PSPLIM value. */
-            "   movs r1, #2                                     \n" /* r1 = 2. */
+            "   mrs  r1, control                                \n" /* Obtain current control register value. */
-            "   msr  CONTROL, r1                                \n" /* Switch to use PSP in the thread mode. */
+            "   orrs r1, r1, #2                                 \n" /* r1 = r1 | 0x2 - Set the second bit to use the program stack pointer (PSP). */
+            "   msr control, r1                                 \n" /* Write back the new control register value. */
             "   adds r0, #32                                    \n" /* Discard everything up to r0. */
             "   msr  psp, r0                                    \n" /* This is now the new top of stack to use in the task. */
             "   isb                                             \n"

portable/GCC/ARM_CM55/non_secure/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -56,6 +58,7 @@
 #define portARCH_NAME                    "Cortex-M55"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         1
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __attribute__( ( used ) )
 /*-----------------------------------------------------------*/
 

portable/GCC/ARM_CM55_NTZ/non_secure/port.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -110,6 +112,7 @@ typedef void ( * portISR_t )( void );
 #define portSCB_VTOR_REG                      ( *( ( portISR_t ** ) 0xe000ed08 ) )
 #define portSCB_SYS_HANDLER_CTRL_STATE_REG    ( *( ( volatile uint32_t * ) 0xe000ed24 ) )
 #define portSCB_MEM_FAULT_ENABLE_BIT          ( 1UL << 16UL )
+#define portSCB_USG_FAULT_ENABLE_BIT          ( 1UL << 18UL )
 /*-----------------------------------------------------------*/
 
 /**
@@ -373,6 +376,20 @@ typedef void ( * portISR_t )( void );
  * any secure calls.
  */
 #define portNO_SECURE_CONTEXT    0
+
+/**
+ * @brief Constants required to check and configure PACBTI security feature implementation.
+ */
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    #define portID_ISAR5_REG         ( *( ( volatile uint32_t * ) 0xe000ed74 ) )
+
+    #define portCONTROL_UPAC_EN      ( 1UL << 7UL )
+    #define portCONTROL_PAC_EN       ( 1UL << 6UL )
+    #define portCONTROL_UBTI_EN      ( 1UL << 5UL )
+    #define portCONTROL_BTI_EN       ( 1UL << 4UL )
+
+#endif /* portHAS_PACBTI_FEATURE */
 /*-----------------------------------------------------------*/
 
 /**
@@ -410,6 +427,26 @@ static void prvTaskExitError( void );
     static void prvSetupFPU( void ) PRIVILEGED_FUNCTION;
 #endif /* configENABLE_FPU */
 
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+/**
+ * @brief Configures PACBTI features.
+ *
+ * This function configures the Pointer Authentication, and Branch Target
+ * Identification security features as per the user configuration. It returns
+ * the value of the special purpose CONTROL register accordingly, and optionally
+ * updates the CONTROL register value. Currently, only Cortex-M85 (ARMv8.1-M
+ * architecture based) target supports PACBTI security feature.
+ *
+ * @param xWriteControlRegister Used to control whether the special purpose
+ * CONTROL register should be updated or not.
+ *
+ * @return CONTROL register value according to the configured PACBTI option.
+ */
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister );
+
+#endif /* portHAS_PACBTI_FEATURE */
+
 /**
  * @brief Setup the timer to generate the tick interrupts.
  *
@@ -1457,6 +1494,7 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
                                          xMPU_SETTINGS * xMPUSettings ) /* PRIVILEGED_FUNCTION */
     {
         uint32_t ulIndex = 0;
+        uint32_t ulControl = 0x0;
 
         xMPUSettings->ulContext[ ulIndex ] = 0x04040404; /* r4. */
         ulIndex++;
@@ -1503,16 +1541,24 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
         xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) pxEndOfStack;         /* PSPLIM. */
         ulIndex++;
 
+        #if ( portHAS_PACBTI_FEATURE == 1 )
+        {
+            /* Check PACBTI security feature configuration before pushing the
+             * CONTROL register's value on task's TCB. */
+            ulControl = prvConfigurePACBTI( pdFALSE );
+        }
+        #endif /* portHAS_PACBTI_FEATURE */
+
         if( xRunPrivileged == pdTRUE )
         {
             xMPUSettings->ulTaskFlags |= portTASK_IS_PRIVILEGED_FLAG;
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
         else
         {
             xMPUSettings->ulTaskFlags &= ( ~portTASK_IS_PRIVILEGED_FLAG );
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
 
@@ -1740,6 +1786,14 @@ BaseType_t xPortStartScheduler( void ) /* PRIVILEGED_FUNCTION */
     portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
     portNVIC_SHPR2_REG = 0;
 
+    #if ( portHAS_PACBTI_FEATURE == 1 )
+    {
+        /* Set the CONTROL register value based on PACBTI security feature
+         * configuration before starting the first task. */
+        ( void) prvConfigurePACBTI( pdTRUE );
+    }
+    #endif /* portHAS_PACBTI_FEATURE */
+
     #if ( configENABLE_MPU == 1 )
     {
         /* Setup the Memory Protection Unit (MPU). */
@@ -2158,3 +2212,42 @@ BaseType_t xPortIsInsideInterrupt( void )
 
 #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */
 /*-----------------------------------------------------------*/
+
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister )
+    {
+        uint32_t ulControl = 0x0;
+
+        /* Ensure that PACBTI is implemented. */
+        configASSERT( portID_ISAR5_REG != 0x0 );
+
+        /* Enable UsageFault exception if PAC or BTI is enabled. */
+        #if( ( configENABLE_PAC == 1 ) || ( configENABLE_BTI == 1 ) )
+        {
+            portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_USG_FAULT_ENABLE_BIT;
+        }
+        #endif
+
+        #if( configENABLE_PAC == 1 )
+        {
+            ulControl |= ( portCONTROL_UPAC_EN | portCONTROL_PAC_EN );
+        }
+        #endif
+
+        #if( configENABLE_BTI == 1 )
+        {
+            ulControl |= ( portCONTROL_UBTI_EN | portCONTROL_BTI_EN );
+        }
+        #endif
+
+        if( xWriteControlRegister == pdTRUE )
+        {
+            __asm volatile ( "msr control, %0" : : "r" ( ulControl ) );
+        }
+
+        return ulControl;
+    }
+
+#endif /* #if ( portHAS_PACBTI_FEATURE == 1 ) */
+/*-----------------------------------------------------------*/

portable/GCC/ARM_CM55_NTZ/non_secure/portasm.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -130,8 +132,9 @@
             "                                                   \n"
             "   ldm  r0!, {r1-r2}                               \n" /* Read from stack - r1 = PSPLIM and r2 = EXC_RETURN. */
             "   msr  psplim, r1                                 \n" /* Set this task's PSPLIM value. */
-            "   movs r1, #2                                     \n" /* r1 = 2. */
+            "   mrs  r1, control                                \n" /* Obtain current control register value. */
-            "   msr  CONTROL, r1                                \n" /* Switch to use PSP in the thread mode. */
+            "   orrs r1, r1, #2                                 \n" /* r1 = r1 | 0x2 - Set the second bit to use the program stack pointer (PSP). */
+            "   msr control, r1                                 \n" /* Write back the new control register value. */
             "   adds r0, #32                                    \n" /* Discard everything up to r0. */
             "   msr  psp, r0                                    \n" /* This is now the new top of stack to use in the task. */
             "   isb                                             \n"

portable/GCC/ARM_CM55_NTZ/non_secure/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -56,6 +58,7 @@
 #define portARCH_NAME                    "Cortex-M55"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         1
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __attribute__( ( used ) )
 /*-----------------------------------------------------------*/
 

portable/GCC/ARM_CM85/non_secure/port.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -110,6 +112,7 @@ typedef void ( * portISR_t )( void );
 #define portSCB_VTOR_REG                      ( *( ( portISR_t ** ) 0xe000ed08 ) )
 #define portSCB_SYS_HANDLER_CTRL_STATE_REG    ( *( ( volatile uint32_t * ) 0xe000ed24 ) )
 #define portSCB_MEM_FAULT_ENABLE_BIT          ( 1UL << 16UL )
+#define portSCB_USG_FAULT_ENABLE_BIT          ( 1UL << 18UL )
 /*-----------------------------------------------------------*/
 
 /**
@@ -373,6 +376,20 @@ typedef void ( * portISR_t )( void );
  * any secure calls.
  */
 #define portNO_SECURE_CONTEXT    0
+
+/**
+ * @brief Constants required to check and configure PACBTI security feature implementation.
+ */
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    #define portID_ISAR5_REG         ( *( ( volatile uint32_t * ) 0xe000ed74 ) )
+
+    #define portCONTROL_UPAC_EN      ( 1UL << 7UL )
+    #define portCONTROL_PAC_EN       ( 1UL << 6UL )
+    #define portCONTROL_UBTI_EN      ( 1UL << 5UL )
+    #define portCONTROL_BTI_EN       ( 1UL << 4UL )
+
+#endif /* portHAS_PACBTI_FEATURE */
 /*-----------------------------------------------------------*/
 
 /**
@@ -410,6 +427,26 @@ static void prvTaskExitError( void );
     static void prvSetupFPU( void ) PRIVILEGED_FUNCTION;
 #endif /* configENABLE_FPU */
 
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+/**
+ * @brief Configures PACBTI features.
+ *
+ * This function configures the Pointer Authentication, and Branch Target
+ * Identification security features as per the user configuration. It returns
+ * the value of the special purpose CONTROL register accordingly, and optionally
+ * updates the CONTROL register value. Currently, only Cortex-M85 (ARMv8.1-M
+ * architecture based) target supports PACBTI security feature.
+ *
+ * @param xWriteControlRegister Used to control whether the special purpose
+ * CONTROL register should be updated or not.
+ *
+ * @return CONTROL register value according to the configured PACBTI option.
+ */
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister );
+
+#endif /* portHAS_PACBTI_FEATURE */
+
 /**
  * @brief Setup the timer to generate the tick interrupts.
  *
@@ -1457,6 +1494,7 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
                                          xMPU_SETTINGS * xMPUSettings ) /* PRIVILEGED_FUNCTION */
     {
         uint32_t ulIndex = 0;
+        uint32_t ulControl = 0x0;
 
         xMPUSettings->ulContext[ ulIndex ] = 0x04040404; /* r4. */
         ulIndex++;
@@ -1503,16 +1541,24 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
         xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) pxEndOfStack;         /* PSPLIM. */
         ulIndex++;
 
+        #if ( portHAS_PACBTI_FEATURE == 1 )
+        {
+            /* Check PACBTI security feature configuration before pushing the
+             * CONTROL register's value on task's TCB. */
+            ulControl = prvConfigurePACBTI( pdFALSE );
+        }
+        #endif /* portHAS_PACBTI_FEATURE */
+
         if( xRunPrivileged == pdTRUE )
         {
             xMPUSettings->ulTaskFlags |= portTASK_IS_PRIVILEGED_FLAG;
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
         else
         {
             xMPUSettings->ulTaskFlags &= ( ~portTASK_IS_PRIVILEGED_FLAG );
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
 
@@ -1740,6 +1786,14 @@ BaseType_t xPortStartScheduler( void ) /* PRIVILEGED_FUNCTION */
     portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
     portNVIC_SHPR2_REG = 0;
 
+    #if ( portHAS_PACBTI_FEATURE == 1 )
+    {
+        /* Set the CONTROL register value based on PACBTI security feature
+         * configuration before starting the first task. */
+        ( void) prvConfigurePACBTI( pdTRUE );
+    }
+    #endif /* portHAS_PACBTI_FEATURE */
+
     #if ( configENABLE_MPU == 1 )
     {
         /* Setup the Memory Protection Unit (MPU). */
@@ -2158,3 +2212,42 @@ BaseType_t xPortIsInsideInterrupt( void )
 
 #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */
 /*-----------------------------------------------------------*/
+
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister )
+    {
+        uint32_t ulControl = 0x0;
+
+        /* Ensure that PACBTI is implemented. */
+        configASSERT( portID_ISAR5_REG != 0x0 );
+
+        /* Enable UsageFault exception if PAC or BTI is enabled. */
+        #if( ( configENABLE_PAC == 1 ) || ( configENABLE_BTI == 1 ) )
+        {
+            portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_USG_FAULT_ENABLE_BIT;
+        }
+        #endif
+
+        #if( configENABLE_PAC == 1 )
+        {
+            ulControl |= ( portCONTROL_UPAC_EN | portCONTROL_PAC_EN );
+        }
+        #endif
+
+        #if( configENABLE_BTI == 1 )
+        {
+            ulControl |= ( portCONTROL_UBTI_EN | portCONTROL_BTI_EN );
+        }
+        #endif
+
+        if( xWriteControlRegister == pdTRUE )
+        {
+            __asm volatile ( "msr control, %0" : : "r" ( ulControl ) );
+        }
+
+        return ulControl;
+    }
+
+#endif /* #if ( portHAS_PACBTI_FEATURE == 1 ) */
+/*-----------------------------------------------------------*/

portable/GCC/ARM_CM85/non_secure/portasm.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -134,8 +136,9 @@
             "   ldr  r4, =xSecureContext                        \n"
             "   str  r1, [r4]                                   \n" /* Set xSecureContext to this task's value for the same. */
             "   msr  psplim, r2                                 \n" /* Set this task's PSPLIM value. */
-            "   movs r1, #2                                     \n" /* r1 = 2. */
+            "   mrs  r1, control                                \n" /* Obtain current control register value. */
-            "   msr  CONTROL, r1                                \n" /* Switch to use PSP in the thread mode. */
+            "   orrs r1, r1, #2                                 \n" /* r1 = r1 | 0x2 - Set the second bit to use the program stack pointer (PSP). */
+            "   msr control, r1                                 \n" /* Write back the new control register value. */
             "   adds r0, #32                                    \n" /* Discard everything up to r0. */
             "   msr  psp, r0                                    \n" /* This is now the new top of stack to use in the task. */
             "   isb                                             \n"

portable/GCC/ARM_CM85/non_secure/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -56,6 +58,7 @@
 #define portARCH_NAME                    "Cortex-M85"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         1
+#define portHAS_PACBTI_FEATURE           1
 #define portDONT_DISCARD                 __attribute__( ( used ) )
 /*-----------------------------------------------------------*/
 

portable/GCC/ARM_CM85_NTZ/non_secure/port.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -110,6 +112,7 @@ typedef void ( * portISR_t )( void );
 #define portSCB_VTOR_REG                      ( *( ( portISR_t ** ) 0xe000ed08 ) )
 #define portSCB_SYS_HANDLER_CTRL_STATE_REG    ( *( ( volatile uint32_t * ) 0xe000ed24 ) )
 #define portSCB_MEM_FAULT_ENABLE_BIT          ( 1UL << 16UL )
+#define portSCB_USG_FAULT_ENABLE_BIT          ( 1UL << 18UL )
 /*-----------------------------------------------------------*/
 
 /**
@@ -373,6 +376,20 @@ typedef void ( * portISR_t )( void );
  * any secure calls.
  */
 #define portNO_SECURE_CONTEXT    0
+
+/**
+ * @brief Constants required to check and configure PACBTI security feature implementation.
+ */
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    #define portID_ISAR5_REG         ( *( ( volatile uint32_t * ) 0xe000ed74 ) )
+
+    #define portCONTROL_UPAC_EN      ( 1UL << 7UL )
+    #define portCONTROL_PAC_EN       ( 1UL << 6UL )
+    #define portCONTROL_UBTI_EN      ( 1UL << 5UL )
+    #define portCONTROL_BTI_EN       ( 1UL << 4UL )
+
+#endif /* portHAS_PACBTI_FEATURE */
 /*-----------------------------------------------------------*/
 
 /**
@@ -410,6 +427,26 @@ static void prvTaskExitError( void );
     static void prvSetupFPU( void ) PRIVILEGED_FUNCTION;
 #endif /* configENABLE_FPU */
 
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+/**
+ * @brief Configures PACBTI features.
+ *
+ * This function configures the Pointer Authentication, and Branch Target
+ * Identification security features as per the user configuration. It returns
+ * the value of the special purpose CONTROL register accordingly, and optionally
+ * updates the CONTROL register value. Currently, only Cortex-M85 (ARMv8.1-M
+ * architecture based) target supports PACBTI security feature.
+ *
+ * @param xWriteControlRegister Used to control whether the special purpose
+ * CONTROL register should be updated or not.
+ *
+ * @return CONTROL register value according to the configured PACBTI option.
+ */
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister );
+
+#endif /* portHAS_PACBTI_FEATURE */
+
 /**
  * @brief Setup the timer to generate the tick interrupts.
  *
@@ -1457,6 +1494,7 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
                                          xMPU_SETTINGS * xMPUSettings ) /* PRIVILEGED_FUNCTION */
     {
         uint32_t ulIndex = 0;
+        uint32_t ulControl = 0x0;
 
         xMPUSettings->ulContext[ ulIndex ] = 0x04040404; /* r4. */
         ulIndex++;
@@ -1503,16 +1541,24 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
         xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) pxEndOfStack;         /* PSPLIM. */
         ulIndex++;
 
+        #if ( portHAS_PACBTI_FEATURE == 1 )
+        {
+            /* Check PACBTI security feature configuration before pushing the
+             * CONTROL register's value on task's TCB. */
+            ulControl = prvConfigurePACBTI( pdFALSE );
+        }
+        #endif /* portHAS_PACBTI_FEATURE */
+
         if( xRunPrivileged == pdTRUE )
         {
             xMPUSettings->ulTaskFlags |= portTASK_IS_PRIVILEGED_FLAG;
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
         else
         {
             xMPUSettings->ulTaskFlags &= ( ~portTASK_IS_PRIVILEGED_FLAG );
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
 
@@ -1740,6 +1786,14 @@ BaseType_t xPortStartScheduler( void ) /* PRIVILEGED_FUNCTION */
     portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
     portNVIC_SHPR2_REG = 0;
 
+    #if ( portHAS_PACBTI_FEATURE == 1 )
+    {
+        /* Set the CONTROL register value based on PACBTI security feature
+         * configuration before starting the first task. */
+        ( void) prvConfigurePACBTI( pdTRUE );
+    }
+    #endif /* portHAS_PACBTI_FEATURE */
+
     #if ( configENABLE_MPU == 1 )
     {
         /* Setup the Memory Protection Unit (MPU). */
@@ -2158,3 +2212,42 @@ BaseType_t xPortIsInsideInterrupt( void )
 
 #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */
 /*-----------------------------------------------------------*/
+
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister )
+    {
+        uint32_t ulControl = 0x0;
+
+        /* Ensure that PACBTI is implemented. */
+        configASSERT( portID_ISAR5_REG != 0x0 );
+
+        /* Enable UsageFault exception if PAC or BTI is enabled. */
+        #if( ( configENABLE_PAC == 1 ) || ( configENABLE_BTI == 1 ) )
+        {
+            portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_USG_FAULT_ENABLE_BIT;
+        }
+        #endif
+
+        #if( configENABLE_PAC == 1 )
+        {
+            ulControl |= ( portCONTROL_UPAC_EN | portCONTROL_PAC_EN );
+        }
+        #endif
+
+        #if( configENABLE_BTI == 1 )
+        {
+            ulControl |= ( portCONTROL_UBTI_EN | portCONTROL_BTI_EN );
+        }
+        #endif
+
+        if( xWriteControlRegister == pdTRUE )
+        {
+            __asm volatile ( "msr control, %0" : : "r" ( ulControl ) );
+        }
+
+        return ulControl;
+    }
+
+#endif /* #if ( portHAS_PACBTI_FEATURE == 1 ) */
+/*-----------------------------------------------------------*/

portable/GCC/ARM_CM85_NTZ/non_secure/portasm.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -130,8 +132,9 @@
             "                                                   \n"
             "   ldm  r0!, {r1-r2}                               \n" /* Read from stack - r1 = PSPLIM and r2 = EXC_RETURN. */
             "   msr  psplim, r1                                 \n" /* Set this task's PSPLIM value. */
-            "   movs r1, #2                                     \n" /* r1 = 2. */
+            "   mrs  r1, control                                \n" /* Obtain current control register value. */
-            "   msr  CONTROL, r1                                \n" /* Switch to use PSP in the thread mode. */
+            "   orrs r1, r1, #2                                 \n" /* r1 = r1 | 0x2 - Set the second bit to use the program stack pointer (PSP). */
+            "   msr control, r1                                 \n" /* Write back the new control register value. */
             "   adds r0, #32                                    \n" /* Discard everything up to r0. */
             "   msr  psp, r0                                    \n" /* This is now the new top of stack to use in the task. */
             "   isb                                             \n"

portable/GCC/ARM_CM85_NTZ/non_secure/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -56,6 +58,7 @@
 #define portARCH_NAME                    "Cortex-M85"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         1
+#define portHAS_PACBTI_FEATURE           1
 #define portDONT_DISCARD                 __attribute__( ( used ) )
 /*-----------------------------------------------------------*/
 

portable/IAR/ARM_CM23/non_secure/port.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -110,6 +112,7 @@ typedef void ( * portISR_t )( void );
 #define portSCB_VTOR_REG                      ( *( ( portISR_t ** ) 0xe000ed08 ) )
 #define portSCB_SYS_HANDLER_CTRL_STATE_REG    ( *( ( volatile uint32_t * ) 0xe000ed24 ) )
 #define portSCB_MEM_FAULT_ENABLE_BIT          ( 1UL << 16UL )
+#define portSCB_USG_FAULT_ENABLE_BIT          ( 1UL << 18UL )
 /*-----------------------------------------------------------*/
 
 /**
@@ -373,6 +376,20 @@ typedef void ( * portISR_t )( void );
  * any secure calls.
  */
 #define portNO_SECURE_CONTEXT    0
+
+/**
+ * @brief Constants required to check and configure PACBTI security feature implementation.
+ */
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    #define portID_ISAR5_REG         ( *( ( volatile uint32_t * ) 0xe000ed74 ) )
+
+    #define portCONTROL_UPAC_EN      ( 1UL << 7UL )
+    #define portCONTROL_PAC_EN       ( 1UL << 6UL )
+    #define portCONTROL_UBTI_EN      ( 1UL << 5UL )
+    #define portCONTROL_BTI_EN       ( 1UL << 4UL )
+
+#endif /* portHAS_PACBTI_FEATURE */
 /*-----------------------------------------------------------*/
 
 /**
@@ -410,6 +427,26 @@ static void prvTaskExitError( void );
     static void prvSetupFPU( void ) PRIVILEGED_FUNCTION;
 #endif /* configENABLE_FPU */
 
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+/**
+ * @brief Configures PACBTI features.
+ *
+ * This function configures the Pointer Authentication, and Branch Target
+ * Identification security features as per the user configuration. It returns
+ * the value of the special purpose CONTROL register accordingly, and optionally
+ * updates the CONTROL register value. Currently, only Cortex-M85 (ARMv8.1-M
+ * architecture based) target supports PACBTI security feature.
+ *
+ * @param xWriteControlRegister Used to control whether the special purpose
+ * CONTROL register should be updated or not.
+ *
+ * @return CONTROL register value according to the configured PACBTI option.
+ */
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister );
+
+#endif /* portHAS_PACBTI_FEATURE */
+
 /**
  * @brief Setup the timer to generate the tick interrupts.
  *
@@ -1457,6 +1494,7 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
                                          xMPU_SETTINGS * xMPUSettings ) /* PRIVILEGED_FUNCTION */
     {
         uint32_t ulIndex = 0;
+        uint32_t ulControl = 0x0;
 
         xMPUSettings->ulContext[ ulIndex ] = 0x04040404; /* r4. */
         ulIndex++;
@@ -1503,16 +1541,24 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
         xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) pxEndOfStack;         /* PSPLIM. */
         ulIndex++;
 
+        #if ( portHAS_PACBTI_FEATURE == 1 )
+        {
+            /* Check PACBTI security feature configuration before pushing the
+             * CONTROL register's value on task's TCB. */
+            ulControl = prvConfigurePACBTI( pdFALSE );
+        }
+        #endif /* portHAS_PACBTI_FEATURE */
+
         if( xRunPrivileged == pdTRUE )
         {
             xMPUSettings->ulTaskFlags |= portTASK_IS_PRIVILEGED_FLAG;
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
         else
         {
             xMPUSettings->ulTaskFlags &= ( ~portTASK_IS_PRIVILEGED_FLAG );
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
 
@@ -1740,6 +1786,14 @@ BaseType_t xPortStartScheduler( void ) /* PRIVILEGED_FUNCTION */
     portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
     portNVIC_SHPR2_REG = 0;
 
+    #if ( portHAS_PACBTI_FEATURE == 1 )
+    {
+        /* Set the CONTROL register value based on PACBTI security feature
+         * configuration before starting the first task. */
+        ( void) prvConfigurePACBTI( pdTRUE );
+    }
+    #endif /* portHAS_PACBTI_FEATURE */
+
     #if ( configENABLE_MPU == 1 )
     {
         /* Setup the Memory Protection Unit (MPU). */
@@ -2158,3 +2212,42 @@ BaseType_t xPortIsInsideInterrupt( void )
 
 #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */
 /*-----------------------------------------------------------*/
+
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister )
+    {
+        uint32_t ulControl = 0x0;
+
+        /* Ensure that PACBTI is implemented. */
+        configASSERT( portID_ISAR5_REG != 0x0 );
+
+        /* Enable UsageFault exception if PAC or BTI is enabled. */
+        #if( ( configENABLE_PAC == 1 ) || ( configENABLE_BTI == 1 ) )
+        {
+            portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_USG_FAULT_ENABLE_BIT;
+        }
+        #endif
+
+        #if( configENABLE_PAC == 1 )
+        {
+            ulControl |= ( portCONTROL_UPAC_EN | portCONTROL_PAC_EN );
+        }
+        #endif
+
+        #if( configENABLE_BTI == 1 )
+        {
+            ulControl |= ( portCONTROL_UBTI_EN | portCONTROL_BTI_EN );
+        }
+        #endif
+
+        if( xWriteControlRegister == pdTRUE )
+        {
+            __asm volatile ( "msr control, %0" : : "r" ( ulControl ) );
+        }
+
+        return ulControl;
+    }
+
+#endif /* #if ( portHAS_PACBTI_FEATURE == 1 ) */
+/*-----------------------------------------------------------*/

portable/IAR/ARM_CM23/non_secure/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -51,6 +53,7 @@
 #define portARCH_NAME                    "Cortex-M23"
 #define portHAS_ARMV8M_MAIN_EXTENSION    0
 #define portARMV8M_MINOR_VERSION         0
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __root
 /*-----------------------------------------------------------*/
 

portable/IAR/ARM_CM23_NTZ/non_secure/port.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -110,6 +112,7 @@ typedef void ( * portISR_t )( void );
 #define portSCB_VTOR_REG                      ( *( ( portISR_t ** ) 0xe000ed08 ) )
 #define portSCB_SYS_HANDLER_CTRL_STATE_REG    ( *( ( volatile uint32_t * ) 0xe000ed24 ) )
 #define portSCB_MEM_FAULT_ENABLE_BIT          ( 1UL << 16UL )
+#define portSCB_USG_FAULT_ENABLE_BIT          ( 1UL << 18UL )
 /*-----------------------------------------------------------*/
 
 /**
@@ -373,6 +376,20 @@ typedef void ( * portISR_t )( void );
  * any secure calls.
  */
 #define portNO_SECURE_CONTEXT    0
+
+/**
+ * @brief Constants required to check and configure PACBTI security feature implementation.
+ */
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    #define portID_ISAR5_REG         ( *( ( volatile uint32_t * ) 0xe000ed74 ) )
+
+    #define portCONTROL_UPAC_EN      ( 1UL << 7UL )
+    #define portCONTROL_PAC_EN       ( 1UL << 6UL )
+    #define portCONTROL_UBTI_EN      ( 1UL << 5UL )
+    #define portCONTROL_BTI_EN       ( 1UL << 4UL )
+
+#endif /* portHAS_PACBTI_FEATURE */
 /*-----------------------------------------------------------*/
 
 /**
@@ -410,6 +427,26 @@ static void prvTaskExitError( void );
     static void prvSetupFPU( void ) PRIVILEGED_FUNCTION;
 #endif /* configENABLE_FPU */
 
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+/**
+ * @brief Configures PACBTI features.
+ *
+ * This function configures the Pointer Authentication, and Branch Target
+ * Identification security features as per the user configuration. It returns
+ * the value of the special purpose CONTROL register accordingly, and optionally
+ * updates the CONTROL register value. Currently, only Cortex-M85 (ARMv8.1-M
+ * architecture based) target supports PACBTI security feature.
+ *
+ * @param xWriteControlRegister Used to control whether the special purpose
+ * CONTROL register should be updated or not.
+ *
+ * @return CONTROL register value according to the configured PACBTI option.
+ */
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister );
+
+#endif /* portHAS_PACBTI_FEATURE */
+
 /**
  * @brief Setup the timer to generate the tick interrupts.
  *
@@ -1457,6 +1494,7 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
                                          xMPU_SETTINGS * xMPUSettings ) /* PRIVILEGED_FUNCTION */
     {
         uint32_t ulIndex = 0;
+        uint32_t ulControl = 0x0;
 
         xMPUSettings->ulContext[ ulIndex ] = 0x04040404; /* r4. */
         ulIndex++;
@@ -1503,16 +1541,24 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
         xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) pxEndOfStack;         /* PSPLIM. */
         ulIndex++;
 
+        #if ( portHAS_PACBTI_FEATURE == 1 )
+        {
+            /* Check PACBTI security feature configuration before pushing the
+             * CONTROL register's value on task's TCB. */
+            ulControl = prvConfigurePACBTI( pdFALSE );
+        }
+        #endif /* portHAS_PACBTI_FEATURE */
+
         if( xRunPrivileged == pdTRUE )
         {
             xMPUSettings->ulTaskFlags |= portTASK_IS_PRIVILEGED_FLAG;
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
         else
         {
             xMPUSettings->ulTaskFlags &= ( ~portTASK_IS_PRIVILEGED_FLAG );
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
 
@@ -1740,6 +1786,14 @@ BaseType_t xPortStartScheduler( void ) /* PRIVILEGED_FUNCTION */
     portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
     portNVIC_SHPR2_REG = 0;
 
+    #if ( portHAS_PACBTI_FEATURE == 1 )
+    {
+        /* Set the CONTROL register value based on PACBTI security feature
+         * configuration before starting the first task. */
+        ( void) prvConfigurePACBTI( pdTRUE );
+    }
+    #endif /* portHAS_PACBTI_FEATURE */
+
     #if ( configENABLE_MPU == 1 )
     {
         /* Setup the Memory Protection Unit (MPU). */
@@ -2158,3 +2212,42 @@ BaseType_t xPortIsInsideInterrupt( void )
 
 #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */
 /*-----------------------------------------------------------*/
+
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister )
+    {
+        uint32_t ulControl = 0x0;
+
+        /* Ensure that PACBTI is implemented. */
+        configASSERT( portID_ISAR5_REG != 0x0 );
+
+        /* Enable UsageFault exception if PAC or BTI is enabled. */
+        #if( ( configENABLE_PAC == 1 ) || ( configENABLE_BTI == 1 ) )
+        {
+            portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_USG_FAULT_ENABLE_BIT;
+        }
+        #endif
+
+        #if( configENABLE_PAC == 1 )
+        {
+            ulControl |= ( portCONTROL_UPAC_EN | portCONTROL_PAC_EN );
+        }
+        #endif
+
+        #if( configENABLE_BTI == 1 )
+        {
+            ulControl |= ( portCONTROL_UBTI_EN | portCONTROL_BTI_EN );
+        }
+        #endif
+
+        if( xWriteControlRegister == pdTRUE )
+        {
+            __asm volatile ( "msr control, %0" : : "r" ( ulControl ) );
+        }
+
+        return ulControl;
+    }
+
+#endif /* #if ( portHAS_PACBTI_FEATURE == 1 ) */
+/*-----------------------------------------------------------*/

portable/IAR/ARM_CM23_NTZ/non_secure/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -51,6 +53,7 @@
 #define portARCH_NAME                    "Cortex-M23"
 #define portHAS_ARMV8M_MAIN_EXTENSION    0
 #define portARMV8M_MINOR_VERSION         0
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __root
 /*-----------------------------------------------------------*/
 

portable/IAR/ARM_CM33/non_secure/port.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -110,6 +112,7 @@ typedef void ( * portISR_t )( void );
 #define portSCB_VTOR_REG                      ( *( ( portISR_t ** ) 0xe000ed08 ) )
 #define portSCB_SYS_HANDLER_CTRL_STATE_REG    ( *( ( volatile uint32_t * ) 0xe000ed24 ) )
 #define portSCB_MEM_FAULT_ENABLE_BIT          ( 1UL << 16UL )
+#define portSCB_USG_FAULT_ENABLE_BIT          ( 1UL << 18UL )
 /*-----------------------------------------------------------*/
 
 /**
@@ -373,6 +376,20 @@ typedef void ( * portISR_t )( void );
  * any secure calls.
  */
 #define portNO_SECURE_CONTEXT    0
+
+/**
+ * @brief Constants required to check and configure PACBTI security feature implementation.
+ */
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    #define portID_ISAR5_REG         ( *( ( volatile uint32_t * ) 0xe000ed74 ) )
+
+    #define portCONTROL_UPAC_EN      ( 1UL << 7UL )
+    #define portCONTROL_PAC_EN       ( 1UL << 6UL )
+    #define portCONTROL_UBTI_EN      ( 1UL << 5UL )
+    #define portCONTROL_BTI_EN       ( 1UL << 4UL )
+
+#endif /* portHAS_PACBTI_FEATURE */
 /*-----------------------------------------------------------*/
 
 /**
@@ -410,6 +427,26 @@ static void prvTaskExitError( void );
     static void prvSetupFPU( void ) PRIVILEGED_FUNCTION;
 #endif /* configENABLE_FPU */
 
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+/**
+ * @brief Configures PACBTI features.
+ *
+ * This function configures the Pointer Authentication, and Branch Target
+ * Identification security features as per the user configuration. It returns
+ * the value of the special purpose CONTROL register accordingly, and optionally
+ * updates the CONTROL register value. Currently, only Cortex-M85 (ARMv8.1-M
+ * architecture based) target supports PACBTI security feature.
+ *
+ * @param xWriteControlRegister Used to control whether the special purpose
+ * CONTROL register should be updated or not.
+ *
+ * @return CONTROL register value according to the configured PACBTI option.
+ */
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister );
+
+#endif /* portHAS_PACBTI_FEATURE */
+
 /**
  * @brief Setup the timer to generate the tick interrupts.
  *
@@ -1457,6 +1494,7 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
                                          xMPU_SETTINGS * xMPUSettings ) /* PRIVILEGED_FUNCTION */
     {
         uint32_t ulIndex = 0;
+        uint32_t ulControl = 0x0;
 
         xMPUSettings->ulContext[ ulIndex ] = 0x04040404; /* r4. */
         ulIndex++;
@@ -1503,16 +1541,24 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
         xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) pxEndOfStack;         /* PSPLIM. */
         ulIndex++;
 
+        #if ( portHAS_PACBTI_FEATURE == 1 )
+        {
+            /* Check PACBTI security feature configuration before pushing the
+             * CONTROL register's value on task's TCB. */
+            ulControl = prvConfigurePACBTI( pdFALSE );
+        }
+        #endif /* portHAS_PACBTI_FEATURE */
+
         if( xRunPrivileged == pdTRUE )
         {
             xMPUSettings->ulTaskFlags |= portTASK_IS_PRIVILEGED_FLAG;
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
         else
         {
             xMPUSettings->ulTaskFlags &= ( ~portTASK_IS_PRIVILEGED_FLAG );
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
 
@@ -1740,6 +1786,14 @@ BaseType_t xPortStartScheduler( void ) /* PRIVILEGED_FUNCTION */
     portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
     portNVIC_SHPR2_REG = 0;
 
+    #if ( portHAS_PACBTI_FEATURE == 1 )
+    {
+        /* Set the CONTROL register value based on PACBTI security feature
+         * configuration before starting the first task. */
+        ( void) prvConfigurePACBTI( pdTRUE );
+    }
+    #endif /* portHAS_PACBTI_FEATURE */
+
     #if ( configENABLE_MPU == 1 )
     {
         /* Setup the Memory Protection Unit (MPU). */
@@ -2158,3 +2212,42 @@ BaseType_t xPortIsInsideInterrupt( void )
 
 #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */
 /*-----------------------------------------------------------*/
+
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister )
+    {
+        uint32_t ulControl = 0x0;
+
+        /* Ensure that PACBTI is implemented. */
+        configASSERT( portID_ISAR5_REG != 0x0 );
+
+        /* Enable UsageFault exception if PAC or BTI is enabled. */
+        #if( ( configENABLE_PAC == 1 ) || ( configENABLE_BTI == 1 ) )
+        {
+            portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_USG_FAULT_ENABLE_BIT;
+        }
+        #endif
+
+        #if( configENABLE_PAC == 1 )
+        {
+            ulControl |= ( portCONTROL_UPAC_EN | portCONTROL_PAC_EN );
+        }
+        #endif
+
+        #if( configENABLE_BTI == 1 )
+        {
+            ulControl |= ( portCONTROL_UBTI_EN | portCONTROL_BTI_EN );
+        }
+        #endif
+
+        if( xWriteControlRegister == pdTRUE )
+        {
+            __asm volatile ( "msr control, %0" : : "r" ( ulControl ) );
+        }
+
+        return ulControl;
+    }
+
+#endif /* #if ( portHAS_PACBTI_FEATURE == 1 ) */
+/*-----------------------------------------------------------*/

portable/IAR/ARM_CM33/non_secure/portasm.s

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -179,8 +181,9 @@ vRestoreContextOfFirstTask:
     ldr  r4, =xSecureContext
     str  r1, [r4]                           /* Set xSecureContext to this task's value for the same. */
     msr  psplim, r2                         /* Set this task's PSPLIM value. */
-    movs r1, #2                             /* r1 = 2. */
+    mrs  r1, control                        /* Obtain current control register value. */
-    msr  CONTROL, r1                        /* Switch to use PSP in the thread mode. */
+    orrs r1, r1, #2                         /* r1 = r1 | 0x2 - Set the second bit to use the program stack pointe (PSP). */
+    msr control, r1                         /* Write back the new control register value. */
     adds r0, #32                            /* Discard everything up to r0. */
     msr  psp, r0                            /* This is now the new top of stack to use in the task. */
     isb

portable/IAR/ARM_CM33/non_secure/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -51,6 +53,7 @@
 #define portARCH_NAME                    "Cortex-M33"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         0
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __root
 /*-----------------------------------------------------------*/
 

portable/IAR/ARM_CM33_NTZ/non_secure/port.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -110,6 +112,7 @@ typedef void ( * portISR_t )( void );
 #define portSCB_VTOR_REG                      ( *( ( portISR_t ** ) 0xe000ed08 ) )
 #define portSCB_SYS_HANDLER_CTRL_STATE_REG    ( *( ( volatile uint32_t * ) 0xe000ed24 ) )
 #define portSCB_MEM_FAULT_ENABLE_BIT          ( 1UL << 16UL )
+#define portSCB_USG_FAULT_ENABLE_BIT          ( 1UL << 18UL )
 /*-----------------------------------------------------------*/
 
 /**
@@ -373,6 +376,20 @@ typedef void ( * portISR_t )( void );
  * any secure calls.
  */
 #define portNO_SECURE_CONTEXT    0
+
+/**
+ * @brief Constants required to check and configure PACBTI security feature implementation.
+ */
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    #define portID_ISAR5_REG         ( *( ( volatile uint32_t * ) 0xe000ed74 ) )
+
+    #define portCONTROL_UPAC_EN      ( 1UL << 7UL )
+    #define portCONTROL_PAC_EN       ( 1UL << 6UL )
+    #define portCONTROL_UBTI_EN      ( 1UL << 5UL )
+    #define portCONTROL_BTI_EN       ( 1UL << 4UL )
+
+#endif /* portHAS_PACBTI_FEATURE */
 /*-----------------------------------------------------------*/
 
 /**
@@ -410,6 +427,26 @@ static void prvTaskExitError( void );
     static void prvSetupFPU( void ) PRIVILEGED_FUNCTION;
 #endif /* configENABLE_FPU */
 
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+/**
+ * @brief Configures PACBTI features.
+ *
+ * This function configures the Pointer Authentication, and Branch Target
+ * Identification security features as per the user configuration. It returns
+ * the value of the special purpose CONTROL register accordingly, and optionally
+ * updates the CONTROL register value. Currently, only Cortex-M85 (ARMv8.1-M
+ * architecture based) target supports PACBTI security feature.
+ *
+ * @param xWriteControlRegister Used to control whether the special purpose
+ * CONTROL register should be updated or not.
+ *
+ * @return CONTROL register value according to the configured PACBTI option.
+ */
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister );
+
+#endif /* portHAS_PACBTI_FEATURE */
+
 /**
  * @brief Setup the timer to generate the tick interrupts.
  *
@@ -1457,6 +1494,7 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
                                          xMPU_SETTINGS * xMPUSettings ) /* PRIVILEGED_FUNCTION */
     {
         uint32_t ulIndex = 0;
+        uint32_t ulControl = 0x0;
 
         xMPUSettings->ulContext[ ulIndex ] = 0x04040404; /* r4. */
         ulIndex++;
@@ -1503,16 +1541,24 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
         xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) pxEndOfStack;         /* PSPLIM. */
         ulIndex++;
 
+        #if ( portHAS_PACBTI_FEATURE == 1 )
+        {
+            /* Check PACBTI security feature configuration before pushing the
+             * CONTROL register's value on task's TCB. */
+            ulControl = prvConfigurePACBTI( pdFALSE );
+        }
+        #endif /* portHAS_PACBTI_FEATURE */
+
         if( xRunPrivileged == pdTRUE )
         {
             xMPUSettings->ulTaskFlags |= portTASK_IS_PRIVILEGED_FLAG;
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
         else
         {
             xMPUSettings->ulTaskFlags &= ( ~portTASK_IS_PRIVILEGED_FLAG );
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
 
@@ -1740,6 +1786,14 @@ BaseType_t xPortStartScheduler( void ) /* PRIVILEGED_FUNCTION */
     portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
     portNVIC_SHPR2_REG = 0;
 
+    #if ( portHAS_PACBTI_FEATURE == 1 )
+    {
+        /* Set the CONTROL register value based on PACBTI security feature
+         * configuration before starting the first task. */
+        ( void) prvConfigurePACBTI( pdTRUE );
+    }
+    #endif /* portHAS_PACBTI_FEATURE */
+
     #if ( configENABLE_MPU == 1 )
     {
         /* Setup the Memory Protection Unit (MPU). */
@@ -2158,3 +2212,42 @@ BaseType_t xPortIsInsideInterrupt( void )
 
 #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */
 /*-----------------------------------------------------------*/
+
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister )
+    {
+        uint32_t ulControl = 0x0;
+
+        /* Ensure that PACBTI is implemented. */
+        configASSERT( portID_ISAR5_REG != 0x0 );
+
+        /* Enable UsageFault exception if PAC or BTI is enabled. */
+        #if( ( configENABLE_PAC == 1 ) || ( configENABLE_BTI == 1 ) )
+        {
+            portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_USG_FAULT_ENABLE_BIT;
+        }
+        #endif
+
+        #if( configENABLE_PAC == 1 )
+        {
+            ulControl |= ( portCONTROL_UPAC_EN | portCONTROL_PAC_EN );
+        }
+        #endif
+
+        #if( configENABLE_BTI == 1 )
+        {
+            ulControl |= ( portCONTROL_UBTI_EN | portCONTROL_BTI_EN );
+        }
+        #endif
+
+        if( xWriteControlRegister == pdTRUE )
+        {
+            __asm volatile ( "msr control, %0" : : "r" ( ulControl ) );
+        }
+
+        return ulControl;
+    }
+
+#endif /* #if ( portHAS_PACBTI_FEATURE == 1 ) */
+/*-----------------------------------------------------------*/

portable/IAR/ARM_CM33_NTZ/non_secure/portasm.s

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -165,8 +167,9 @@ vRestoreContextOfFirstTask:
 
     ldm  r0!, {r1-r2}                       /* Read from stack - r1 = PSPLIM and r2 = EXC_RETURN. */
     msr  psplim, r1                         /* Set this task's PSPLIM value. */
-    movs r1, #2                             /* r1 = 2. */
+    mrs  r1, control                        /* Obtain current control register value. */
-    msr  CONTROL, r1                        /* Switch to use PSP in the thread mode. */
+    orrs r1, r1, #2                         /* r1 = r1 | 0x2 - Set the second bit to use the program stack pointe (PSP). */
+    msr control, r1                         /* Write back the new control register value. */
     adds r0, #32                            /* Discard everything up to r0. */
     msr  psp, r0                            /* This is now the new top of stack to use in the task. */
     isb

portable/IAR/ARM_CM33_NTZ/non_secure/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -51,6 +53,7 @@
 #define portARCH_NAME                    "Cortex-M33"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         0
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __root
 /*-----------------------------------------------------------*/
 

portable/IAR/ARM_CM35P/non_secure/port.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -110,6 +112,7 @@ typedef void ( * portISR_t )( void );
 #define portSCB_VTOR_REG                      ( *( ( portISR_t ** ) 0xe000ed08 ) )
 #define portSCB_SYS_HANDLER_CTRL_STATE_REG    ( *( ( volatile uint32_t * ) 0xe000ed24 ) )
 #define portSCB_MEM_FAULT_ENABLE_BIT          ( 1UL << 16UL )
+#define portSCB_USG_FAULT_ENABLE_BIT          ( 1UL << 18UL )
 /*-----------------------------------------------------------*/
 
 /**
@@ -373,6 +376,20 @@ typedef void ( * portISR_t )( void );
  * any secure calls.
  */
 #define portNO_SECURE_CONTEXT    0
+
+/**
+ * @brief Constants required to check and configure PACBTI security feature implementation.
+ */
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    #define portID_ISAR5_REG         ( *( ( volatile uint32_t * ) 0xe000ed74 ) )
+
+    #define portCONTROL_UPAC_EN      ( 1UL << 7UL )
+    #define portCONTROL_PAC_EN       ( 1UL << 6UL )
+    #define portCONTROL_UBTI_EN      ( 1UL << 5UL )
+    #define portCONTROL_BTI_EN       ( 1UL << 4UL )
+
+#endif /* portHAS_PACBTI_FEATURE */
 /*-----------------------------------------------------------*/
 
 /**
@@ -410,6 +427,26 @@ static void prvTaskExitError( void );
     static void prvSetupFPU( void ) PRIVILEGED_FUNCTION;
 #endif /* configENABLE_FPU */
 
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+/**
+ * @brief Configures PACBTI features.
+ *
+ * This function configures the Pointer Authentication, and Branch Target
+ * Identification security features as per the user configuration. It returns
+ * the value of the special purpose CONTROL register accordingly, and optionally
+ * updates the CONTROL register value. Currently, only Cortex-M85 (ARMv8.1-M
+ * architecture based) target supports PACBTI security feature.
+ *
+ * @param xWriteControlRegister Used to control whether the special purpose
+ * CONTROL register should be updated or not.
+ *
+ * @return CONTROL register value according to the configured PACBTI option.
+ */
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister );
+
+#endif /* portHAS_PACBTI_FEATURE */
+
 /**
  * @brief Setup the timer to generate the tick interrupts.
  *
@@ -1457,6 +1494,7 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
                                          xMPU_SETTINGS * xMPUSettings ) /* PRIVILEGED_FUNCTION */
     {
         uint32_t ulIndex = 0;
+        uint32_t ulControl = 0x0;
 
         xMPUSettings->ulContext[ ulIndex ] = 0x04040404; /* r4. */
         ulIndex++;
@@ -1503,16 +1541,24 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
         xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) pxEndOfStack;         /* PSPLIM. */
         ulIndex++;
 
+        #if ( portHAS_PACBTI_FEATURE == 1 )
+        {
+            /* Check PACBTI security feature configuration before pushing the
+             * CONTROL register's value on task's TCB. */
+            ulControl = prvConfigurePACBTI( pdFALSE );
+        }
+        #endif /* portHAS_PACBTI_FEATURE */
+
         if( xRunPrivileged == pdTRUE )
         {
             xMPUSettings->ulTaskFlags |= portTASK_IS_PRIVILEGED_FLAG;
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
         else
         {
             xMPUSettings->ulTaskFlags &= ( ~portTASK_IS_PRIVILEGED_FLAG );
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
 
@@ -1740,6 +1786,14 @@ BaseType_t xPortStartScheduler( void ) /* PRIVILEGED_FUNCTION */
     portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
     portNVIC_SHPR2_REG = 0;
 
+    #if ( portHAS_PACBTI_FEATURE == 1 )
+    {
+        /* Set the CONTROL register value based on PACBTI security feature
+         * configuration before starting the first task. */
+        ( void) prvConfigurePACBTI( pdTRUE );
+    }
+    #endif /* portHAS_PACBTI_FEATURE */
+
     #if ( configENABLE_MPU == 1 )
     {
         /* Setup the Memory Protection Unit (MPU). */
@@ -2158,3 +2212,42 @@ BaseType_t xPortIsInsideInterrupt( void )
 
 #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */
 /*-----------------------------------------------------------*/
+
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister )
+    {
+        uint32_t ulControl = 0x0;
+
+        /* Ensure that PACBTI is implemented. */
+        configASSERT( portID_ISAR5_REG != 0x0 );
+
+        /* Enable UsageFault exception if PAC or BTI is enabled. */
+        #if( ( configENABLE_PAC == 1 ) || ( configENABLE_BTI == 1 ) )
+        {
+            portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_USG_FAULT_ENABLE_BIT;
+        }
+        #endif
+
+        #if( configENABLE_PAC == 1 )
+        {
+            ulControl |= ( portCONTROL_UPAC_EN | portCONTROL_PAC_EN );
+        }
+        #endif
+
+        #if( configENABLE_BTI == 1 )
+        {
+            ulControl |= ( portCONTROL_UBTI_EN | portCONTROL_BTI_EN );
+        }
+        #endif
+
+        if( xWriteControlRegister == pdTRUE )
+        {
+            __asm volatile ( "msr control, %0" : : "r" ( ulControl ) );
+        }
+
+        return ulControl;
+    }
+
+#endif /* #if ( portHAS_PACBTI_FEATURE == 1 ) */
+/*-----------------------------------------------------------*/

portable/IAR/ARM_CM35P/non_secure/portasm.s

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -179,8 +181,9 @@ vRestoreContextOfFirstTask:
     ldr  r4, =xSecureContext
     str  r1, [r4]                           /* Set xSecureContext to this task's value for the same. */
     msr  psplim, r2                         /* Set this task's PSPLIM value. */
-    movs r1, #2                             /* r1 = 2. */
+    mrs  r1, control                        /* Obtain current control register value. */
-    msr  CONTROL, r1                        /* Switch to use PSP in the thread mode. */
+    orrs r1, r1, #2                         /* r1 = r1 | 0x2 - Set the second bit to use the program stack pointe (PSP). */
+    msr control, r1                         /* Write back the new control register value. */
     adds r0, #32                            /* Discard everything up to r0. */
     msr  psp, r0                            /* This is now the new top of stack to use in the task. */
     isb

portable/IAR/ARM_CM35P/non_secure/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -51,6 +53,7 @@
 #define portARCH_NAME                    "Cortex-M35P"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         0
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __root
 /*-----------------------------------------------------------*/
 

portable/IAR/ARM_CM35P_NTZ/non_secure/port.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -110,6 +112,7 @@ typedef void ( * portISR_t )( void );
 #define portSCB_VTOR_REG                      ( *( ( portISR_t ** ) 0xe000ed08 ) )
 #define portSCB_SYS_HANDLER_CTRL_STATE_REG    ( *( ( volatile uint32_t * ) 0xe000ed24 ) )
 #define portSCB_MEM_FAULT_ENABLE_BIT          ( 1UL << 16UL )
+#define portSCB_USG_FAULT_ENABLE_BIT          ( 1UL << 18UL )
 /*-----------------------------------------------------------*/
 
 /**
@@ -373,6 +376,20 @@ typedef void ( * portISR_t )( void );
  * any secure calls.
  */
 #define portNO_SECURE_CONTEXT    0
+
+/**
+ * @brief Constants required to check and configure PACBTI security feature implementation.
+ */
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    #define portID_ISAR5_REG         ( *( ( volatile uint32_t * ) 0xe000ed74 ) )
+
+    #define portCONTROL_UPAC_EN      ( 1UL << 7UL )
+    #define portCONTROL_PAC_EN       ( 1UL << 6UL )
+    #define portCONTROL_UBTI_EN      ( 1UL << 5UL )
+    #define portCONTROL_BTI_EN       ( 1UL << 4UL )
+
+#endif /* portHAS_PACBTI_FEATURE */
 /*-----------------------------------------------------------*/
 
 /**
@@ -410,6 +427,26 @@ static void prvTaskExitError( void );
     static void prvSetupFPU( void ) PRIVILEGED_FUNCTION;
 #endif /* configENABLE_FPU */
 
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+/**
+ * @brief Configures PACBTI features.
+ *
+ * This function configures the Pointer Authentication, and Branch Target
+ * Identification security features as per the user configuration. It returns
+ * the value of the special purpose CONTROL register accordingly, and optionally
+ * updates the CONTROL register value. Currently, only Cortex-M85 (ARMv8.1-M
+ * architecture based) target supports PACBTI security feature.
+ *
+ * @param xWriteControlRegister Used to control whether the special purpose
+ * CONTROL register should be updated or not.
+ *
+ * @return CONTROL register value according to the configured PACBTI option.
+ */
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister );
+
+#endif /* portHAS_PACBTI_FEATURE */
+
 /**
  * @brief Setup the timer to generate the tick interrupts.
  *
@@ -1457,6 +1494,7 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
                                          xMPU_SETTINGS * xMPUSettings ) /* PRIVILEGED_FUNCTION */
     {
         uint32_t ulIndex = 0;
+        uint32_t ulControl = 0x0;
 
         xMPUSettings->ulContext[ ulIndex ] = 0x04040404; /* r4. */
         ulIndex++;
@@ -1503,16 +1541,24 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
         xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) pxEndOfStack;         /* PSPLIM. */
         ulIndex++;
 
+        #if ( portHAS_PACBTI_FEATURE == 1 )
+        {
+            /* Check PACBTI security feature configuration before pushing the
+             * CONTROL register's value on task's TCB. */
+            ulControl = prvConfigurePACBTI( pdFALSE );
+        }
+        #endif /* portHAS_PACBTI_FEATURE */
+
         if( xRunPrivileged == pdTRUE )
         {
             xMPUSettings->ulTaskFlags |= portTASK_IS_PRIVILEGED_FLAG;
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
         else
         {
             xMPUSettings->ulTaskFlags &= ( ~portTASK_IS_PRIVILEGED_FLAG );
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
 
@@ -1740,6 +1786,14 @@ BaseType_t xPortStartScheduler( void ) /* PRIVILEGED_FUNCTION */
     portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
     portNVIC_SHPR2_REG = 0;
 
+    #if ( portHAS_PACBTI_FEATURE == 1 )
+    {
+        /* Set the CONTROL register value based on PACBTI security feature
+         * configuration before starting the first task. */
+        ( void) prvConfigurePACBTI( pdTRUE );
+    }
+    #endif /* portHAS_PACBTI_FEATURE */
+
     #if ( configENABLE_MPU == 1 )
     {
         /* Setup the Memory Protection Unit (MPU). */
@@ -2158,3 +2212,42 @@ BaseType_t xPortIsInsideInterrupt( void )
 
 #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */
 /*-----------------------------------------------------------*/
+
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister )
+    {
+        uint32_t ulControl = 0x0;
+
+        /* Ensure that PACBTI is implemented. */
+        configASSERT( portID_ISAR5_REG != 0x0 );
+
+        /* Enable UsageFault exception if PAC or BTI is enabled. */
+        #if( ( configENABLE_PAC == 1 ) || ( configENABLE_BTI == 1 ) )
+        {
+            portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_USG_FAULT_ENABLE_BIT;
+        }
+        #endif
+
+        #if( configENABLE_PAC == 1 )
+        {
+            ulControl |= ( portCONTROL_UPAC_EN | portCONTROL_PAC_EN );
+        }
+        #endif
+
+        #if( configENABLE_BTI == 1 )
+        {
+            ulControl |= ( portCONTROL_UBTI_EN | portCONTROL_BTI_EN );
+        }
+        #endif
+
+        if( xWriteControlRegister == pdTRUE )
+        {
+            __asm volatile ( "msr control, %0" : : "r" ( ulControl ) );
+        }
+
+        return ulControl;
+    }
+
+#endif /* #if ( portHAS_PACBTI_FEATURE == 1 ) */
+/*-----------------------------------------------------------*/

portable/IAR/ARM_CM35P_NTZ/non_secure/portasm.s

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -165,8 +167,9 @@ vRestoreContextOfFirstTask:
 
     ldm  r0!, {r1-r2}                       /* Read from stack - r1 = PSPLIM and r2 = EXC_RETURN. */
     msr  psplim, r1                         /* Set this task's PSPLIM value. */
-    movs r1, #2                             /* r1 = 2. */
+    mrs  r1, control                        /* Obtain current control register value. */
-    msr  CONTROL, r1                        /* Switch to use PSP in the thread mode. */
+    orrs r1, r1, #2                         /* r1 = r1 | 0x2 - Set the second bit to use the program stack pointe (PSP). */
+    msr control, r1                         /* Write back the new control register value. */
     adds r0, #32                            /* Discard everything up to r0. */
     msr  psp, r0                            /* This is now the new top of stack to use in the task. */
     isb

portable/IAR/ARM_CM35P_NTZ/non_secure/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -51,6 +53,7 @@
 #define portARCH_NAME                    "Cortex-M35P"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         0
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __root
 /*-----------------------------------------------------------*/
 

portable/IAR/ARM_CM55/non_secure/port.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -110,6 +112,7 @@ typedef void ( * portISR_t )( void );
 #define portSCB_VTOR_REG                      ( *( ( portISR_t ** ) 0xe000ed08 ) )
 #define portSCB_SYS_HANDLER_CTRL_STATE_REG    ( *( ( volatile uint32_t * ) 0xe000ed24 ) )
 #define portSCB_MEM_FAULT_ENABLE_BIT          ( 1UL << 16UL )
+#define portSCB_USG_FAULT_ENABLE_BIT          ( 1UL << 18UL )
 /*-----------------------------------------------------------*/
 
 /**
@@ -373,6 +376,20 @@ typedef void ( * portISR_t )( void );
  * any secure calls.
  */
 #define portNO_SECURE_CONTEXT    0
+
+/**
+ * @brief Constants required to check and configure PACBTI security feature implementation.
+ */
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    #define portID_ISAR5_REG         ( *( ( volatile uint32_t * ) 0xe000ed74 ) )
+
+    #define portCONTROL_UPAC_EN      ( 1UL << 7UL )
+    #define portCONTROL_PAC_EN       ( 1UL << 6UL )
+    #define portCONTROL_UBTI_EN      ( 1UL << 5UL )
+    #define portCONTROL_BTI_EN       ( 1UL << 4UL )
+
+#endif /* portHAS_PACBTI_FEATURE */
 /*-----------------------------------------------------------*/
 
 /**
@@ -410,6 +427,26 @@ static void prvTaskExitError( void );
     static void prvSetupFPU( void ) PRIVILEGED_FUNCTION;
 #endif /* configENABLE_FPU */
 
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+/**
+ * @brief Configures PACBTI features.
+ *
+ * This function configures the Pointer Authentication, and Branch Target
+ * Identification security features as per the user configuration. It returns
+ * the value of the special purpose CONTROL register accordingly, and optionally
+ * updates the CONTROL register value. Currently, only Cortex-M85 (ARMv8.1-M
+ * architecture based) target supports PACBTI security feature.
+ *
+ * @param xWriteControlRegister Used to control whether the special purpose
+ * CONTROL register should be updated or not.
+ *
+ * @return CONTROL register value according to the configured PACBTI option.
+ */
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister );
+
+#endif /* portHAS_PACBTI_FEATURE */
+
 /**
  * @brief Setup the timer to generate the tick interrupts.
  *
@@ -1457,6 +1494,7 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
                                          xMPU_SETTINGS * xMPUSettings ) /* PRIVILEGED_FUNCTION */
     {
         uint32_t ulIndex = 0;
+        uint32_t ulControl = 0x0;
 
         xMPUSettings->ulContext[ ulIndex ] = 0x04040404; /* r4. */
         ulIndex++;
@@ -1503,16 +1541,24 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
         xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) pxEndOfStack;         /* PSPLIM. */
         ulIndex++;
 
+        #if ( portHAS_PACBTI_FEATURE == 1 )
+        {
+            /* Check PACBTI security feature configuration before pushing the
+             * CONTROL register's value on task's TCB. */
+            ulControl = prvConfigurePACBTI( pdFALSE );
+        }
+        #endif /* portHAS_PACBTI_FEATURE */
+
         if( xRunPrivileged == pdTRUE )
         {
             xMPUSettings->ulTaskFlags |= portTASK_IS_PRIVILEGED_FLAG;
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
         else
         {
             xMPUSettings->ulTaskFlags &= ( ~portTASK_IS_PRIVILEGED_FLAG );
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
 
@@ -1740,6 +1786,14 @@ BaseType_t xPortStartScheduler( void ) /* PRIVILEGED_FUNCTION */
     portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
     portNVIC_SHPR2_REG = 0;
 
+    #if ( portHAS_PACBTI_FEATURE == 1 )
+    {
+        /* Set the CONTROL register value based on PACBTI security feature
+         * configuration before starting the first task. */
+        ( void) prvConfigurePACBTI( pdTRUE );
+    }
+    #endif /* portHAS_PACBTI_FEATURE */
+
     #if ( configENABLE_MPU == 1 )
     {
         /* Setup the Memory Protection Unit (MPU). */
@@ -2158,3 +2212,42 @@ BaseType_t xPortIsInsideInterrupt( void )
 
 #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */
 /*-----------------------------------------------------------*/
+
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister )
+    {
+        uint32_t ulControl = 0x0;
+
+        /* Ensure that PACBTI is implemented. */
+        configASSERT( portID_ISAR5_REG != 0x0 );
+
+        /* Enable UsageFault exception if PAC or BTI is enabled. */
+        #if( ( configENABLE_PAC == 1 ) || ( configENABLE_BTI == 1 ) )
+        {
+            portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_USG_FAULT_ENABLE_BIT;
+        }
+        #endif
+
+        #if( configENABLE_PAC == 1 )
+        {
+            ulControl |= ( portCONTROL_UPAC_EN | portCONTROL_PAC_EN );
+        }
+        #endif
+
+        #if( configENABLE_BTI == 1 )
+        {
+            ulControl |= ( portCONTROL_UBTI_EN | portCONTROL_BTI_EN );
+        }
+        #endif
+
+        if( xWriteControlRegister == pdTRUE )
+        {
+            __asm volatile ( "msr control, %0" : : "r" ( ulControl ) );
+        }
+
+        return ulControl;
+    }
+
+#endif /* #if ( portHAS_PACBTI_FEATURE == 1 ) */
+/*-----------------------------------------------------------*/

portable/IAR/ARM_CM55/non_secure/portasm.s

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -179,8 +181,9 @@ vRestoreContextOfFirstTask:
     ldr  r4, =xSecureContext
     str  r1, [r4]                           /* Set xSecureContext to this task's value for the same. */
     msr  psplim, r2                         /* Set this task's PSPLIM value. */
-    movs r1, #2                             /* r1 = 2. */
+    mrs  r1, control                        /* Obtain current control register value. */
-    msr  CONTROL, r1                        /* Switch to use PSP in the thread mode. */
+    orrs r1, r1, #2                         /* r1 = r1 | 0x2 - Set the second bit to use the program stack pointe (PSP). */
+    msr control, r1                         /* Write back the new control register value. */
     adds r0, #32                            /* Discard everything up to r0. */
     msr  psp, r0                            /* This is now the new top of stack to use in the task. */
     isb

portable/IAR/ARM_CM55/non_secure/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -56,6 +58,7 @@
 #define portARCH_NAME                    "Cortex-M55"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         1
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __root
 /*-----------------------------------------------------------*/
 

portable/IAR/ARM_CM55_NTZ/non_secure/port.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -110,6 +112,7 @@ typedef void ( * portISR_t )( void );
 #define portSCB_VTOR_REG                      ( *( ( portISR_t ** ) 0xe000ed08 ) )
 #define portSCB_SYS_HANDLER_CTRL_STATE_REG    ( *( ( volatile uint32_t * ) 0xe000ed24 ) )
 #define portSCB_MEM_FAULT_ENABLE_BIT          ( 1UL << 16UL )
+#define portSCB_USG_FAULT_ENABLE_BIT          ( 1UL << 18UL )
 /*-----------------------------------------------------------*/
 
 /**
@@ -373,6 +376,20 @@ typedef void ( * portISR_t )( void );
  * any secure calls.
  */
 #define portNO_SECURE_CONTEXT    0
+
+/**
+ * @brief Constants required to check and configure PACBTI security feature implementation.
+ */
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    #define portID_ISAR5_REG         ( *( ( volatile uint32_t * ) 0xe000ed74 ) )
+
+    #define portCONTROL_UPAC_EN      ( 1UL << 7UL )
+    #define portCONTROL_PAC_EN       ( 1UL << 6UL )
+    #define portCONTROL_UBTI_EN      ( 1UL << 5UL )
+    #define portCONTROL_BTI_EN       ( 1UL << 4UL )
+
+#endif /* portHAS_PACBTI_FEATURE */
 /*-----------------------------------------------------------*/
 
 /**
@@ -410,6 +427,26 @@ static void prvTaskExitError( void );
     static void prvSetupFPU( void ) PRIVILEGED_FUNCTION;
 #endif /* configENABLE_FPU */
 
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+/**
+ * @brief Configures PACBTI features.
+ *
+ * This function configures the Pointer Authentication, and Branch Target
+ * Identification security features as per the user configuration. It returns
+ * the value of the special purpose CONTROL register accordingly, and optionally
+ * updates the CONTROL register value. Currently, only Cortex-M85 (ARMv8.1-M
+ * architecture based) target supports PACBTI security feature.
+ *
+ * @param xWriteControlRegister Used to control whether the special purpose
+ * CONTROL register should be updated or not.
+ *
+ * @return CONTROL register value according to the configured PACBTI option.
+ */
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister );
+
+#endif /* portHAS_PACBTI_FEATURE */
+
 /**
  * @brief Setup the timer to generate the tick interrupts.
  *
@@ -1457,6 +1494,7 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
                                          xMPU_SETTINGS * xMPUSettings ) /* PRIVILEGED_FUNCTION */
     {
         uint32_t ulIndex = 0;
+        uint32_t ulControl = 0x0;
 
         xMPUSettings->ulContext[ ulIndex ] = 0x04040404; /* r4. */
         ulIndex++;
@@ -1503,16 +1541,24 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
         xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) pxEndOfStack;         /* PSPLIM. */
         ulIndex++;
 
+        #if ( portHAS_PACBTI_FEATURE == 1 )
+        {
+            /* Check PACBTI security feature configuration before pushing the
+             * CONTROL register's value on task's TCB. */
+            ulControl = prvConfigurePACBTI( pdFALSE );
+        }
+        #endif /* portHAS_PACBTI_FEATURE */
+
         if( xRunPrivileged == pdTRUE )
         {
             xMPUSettings->ulTaskFlags |= portTASK_IS_PRIVILEGED_FLAG;
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
         else
         {
             xMPUSettings->ulTaskFlags &= ( ~portTASK_IS_PRIVILEGED_FLAG );
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
 
@@ -1740,6 +1786,14 @@ BaseType_t xPortStartScheduler( void ) /* PRIVILEGED_FUNCTION */
     portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
     portNVIC_SHPR2_REG = 0;
 
+    #if ( portHAS_PACBTI_FEATURE == 1 )
+    {
+        /* Set the CONTROL register value based on PACBTI security feature
+         * configuration before starting the first task. */
+        ( void) prvConfigurePACBTI( pdTRUE );
+    }
+    #endif /* portHAS_PACBTI_FEATURE */
+
     #if ( configENABLE_MPU == 1 )
     {
         /* Setup the Memory Protection Unit (MPU). */
@@ -2158,3 +2212,42 @@ BaseType_t xPortIsInsideInterrupt( void )
 
 #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */
 /*-----------------------------------------------------------*/
+
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister )
+    {
+        uint32_t ulControl = 0x0;
+
+        /* Ensure that PACBTI is implemented. */
+        configASSERT( portID_ISAR5_REG != 0x0 );
+
+        /* Enable UsageFault exception if PAC or BTI is enabled. */
+        #if( ( configENABLE_PAC == 1 ) || ( configENABLE_BTI == 1 ) )
+        {
+            portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_USG_FAULT_ENABLE_BIT;
+        }
+        #endif
+
+        #if( configENABLE_PAC == 1 )
+        {
+            ulControl |= ( portCONTROL_UPAC_EN | portCONTROL_PAC_EN );
+        }
+        #endif
+
+        #if( configENABLE_BTI == 1 )
+        {
+            ulControl |= ( portCONTROL_UBTI_EN | portCONTROL_BTI_EN );
+        }
+        #endif
+
+        if( xWriteControlRegister == pdTRUE )
+        {
+            __asm volatile ( "msr control, %0" : : "r" ( ulControl ) );
+        }
+
+        return ulControl;
+    }
+
+#endif /* #if ( portHAS_PACBTI_FEATURE == 1 ) */
+/*-----------------------------------------------------------*/

portable/IAR/ARM_CM55_NTZ/non_secure/portasm.s

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -165,8 +167,9 @@ vRestoreContextOfFirstTask:
 
     ldm  r0!, {r1-r2}                       /* Read from stack - r1 = PSPLIM and r2 = EXC_RETURN. */
     msr  psplim, r1                         /* Set this task's PSPLIM value. */
-    movs r1, #2                             /* r1 = 2. */
+    mrs  r1, control                        /* Obtain current control register value. */
-    msr  CONTROL, r1                        /* Switch to use PSP in the thread mode. */
+    orrs r1, r1, #2                         /* r1 = r1 | 0x2 - Set the second bit to use the program stack pointe (PSP). */
+    msr control, r1                         /* Write back the new control register value. */
     adds r0, #32                            /* Discard everything up to r0. */
     msr  psp, r0                            /* This is now the new top of stack to use in the task. */
     isb

portable/IAR/ARM_CM55_NTZ/non_secure/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -56,6 +58,7 @@
 #define portARCH_NAME                    "Cortex-M55"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         1
+#define portHAS_PACBTI_FEATURE           0
 #define portDONT_DISCARD                 __root
 /*-----------------------------------------------------------*/
 

portable/IAR/ARM_CM85/non_secure/port.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -110,6 +112,7 @@ typedef void ( * portISR_t )( void );
 #define portSCB_VTOR_REG                      ( *( ( portISR_t ** ) 0xe000ed08 ) )
 #define portSCB_SYS_HANDLER_CTRL_STATE_REG    ( *( ( volatile uint32_t * ) 0xe000ed24 ) )
 #define portSCB_MEM_FAULT_ENABLE_BIT          ( 1UL << 16UL )
+#define portSCB_USG_FAULT_ENABLE_BIT          ( 1UL << 18UL )
 /*-----------------------------------------------------------*/
 
 /**
@@ -373,6 +376,20 @@ typedef void ( * portISR_t )( void );
  * any secure calls.
  */
 #define portNO_SECURE_CONTEXT    0
+
+/**
+ * @brief Constants required to check and configure PACBTI security feature implementation.
+ */
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    #define portID_ISAR5_REG         ( *( ( volatile uint32_t * ) 0xe000ed74 ) )
+
+    #define portCONTROL_UPAC_EN      ( 1UL << 7UL )
+    #define portCONTROL_PAC_EN       ( 1UL << 6UL )
+    #define portCONTROL_UBTI_EN      ( 1UL << 5UL )
+    #define portCONTROL_BTI_EN       ( 1UL << 4UL )
+
+#endif /* portHAS_PACBTI_FEATURE */
 /*-----------------------------------------------------------*/
 
 /**
@@ -410,6 +427,26 @@ static void prvTaskExitError( void );
     static void prvSetupFPU( void ) PRIVILEGED_FUNCTION;
 #endif /* configENABLE_FPU */
 
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+/**
+ * @brief Configures PACBTI features.
+ *
+ * This function configures the Pointer Authentication, and Branch Target
+ * Identification security features as per the user configuration. It returns
+ * the value of the special purpose CONTROL register accordingly, and optionally
+ * updates the CONTROL register value. Currently, only Cortex-M85 (ARMv8.1-M
+ * architecture based) target supports PACBTI security feature.
+ *
+ * @param xWriteControlRegister Used to control whether the special purpose
+ * CONTROL register should be updated or not.
+ *
+ * @return CONTROL register value according to the configured PACBTI option.
+ */
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister );
+
+#endif /* portHAS_PACBTI_FEATURE */
+
 /**
  * @brief Setup the timer to generate the tick interrupts.
  *
@@ -1457,6 +1494,7 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
                                          xMPU_SETTINGS * xMPUSettings ) /* PRIVILEGED_FUNCTION */
     {
         uint32_t ulIndex = 0;
+        uint32_t ulControl = 0x0;
 
         xMPUSettings->ulContext[ ulIndex ] = 0x04040404; /* r4. */
         ulIndex++;
@@ -1503,16 +1541,24 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
         xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) pxEndOfStack;         /* PSPLIM. */
         ulIndex++;
 
+        #if ( portHAS_PACBTI_FEATURE == 1 )
+        {
+            /* Check PACBTI security feature configuration before pushing the
+             * CONTROL register's value on task's TCB. */
+            ulControl = prvConfigurePACBTI( pdFALSE );
+        }
+        #endif /* portHAS_PACBTI_FEATURE */
+
         if( xRunPrivileged == pdTRUE )
         {
             xMPUSettings->ulTaskFlags |= portTASK_IS_PRIVILEGED_FLAG;
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
         else
         {
             xMPUSettings->ulTaskFlags &= ( ~portTASK_IS_PRIVILEGED_FLAG );
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
 
@@ -1740,6 +1786,14 @@ BaseType_t xPortStartScheduler( void ) /* PRIVILEGED_FUNCTION */
     portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
     portNVIC_SHPR2_REG = 0;
 
+    #if ( portHAS_PACBTI_FEATURE == 1 )
+    {
+        /* Set the CONTROL register value based on PACBTI security feature
+         * configuration before starting the first task. */
+        ( void) prvConfigurePACBTI( pdTRUE );
+    }
+    #endif /* portHAS_PACBTI_FEATURE */
+
     #if ( configENABLE_MPU == 1 )
     {
         /* Setup the Memory Protection Unit (MPU). */
@@ -2158,3 +2212,42 @@ BaseType_t xPortIsInsideInterrupt( void )
 
 #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */
 /*-----------------------------------------------------------*/
+
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister )
+    {
+        uint32_t ulControl = 0x0;
+
+        /* Ensure that PACBTI is implemented. */
+        configASSERT( portID_ISAR5_REG != 0x0 );
+
+        /* Enable UsageFault exception if PAC or BTI is enabled. */
+        #if( ( configENABLE_PAC == 1 ) || ( configENABLE_BTI == 1 ) )
+        {
+            portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_USG_FAULT_ENABLE_BIT;
+        }
+        #endif
+
+        #if( configENABLE_PAC == 1 )
+        {
+            ulControl |= ( portCONTROL_UPAC_EN | portCONTROL_PAC_EN );
+        }
+        #endif
+
+        #if( configENABLE_BTI == 1 )
+        {
+            ulControl |= ( portCONTROL_UBTI_EN | portCONTROL_BTI_EN );
+        }
+        #endif
+
+        if( xWriteControlRegister == pdTRUE )
+        {
+            __asm volatile ( "msr control, %0" : : "r" ( ulControl ) );
+        }
+
+        return ulControl;
+    }
+
+#endif /* #if ( portHAS_PACBTI_FEATURE == 1 ) */
+/*-----------------------------------------------------------*/

portable/IAR/ARM_CM85/non_secure/portasm.s

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -179,8 +181,9 @@ vRestoreContextOfFirstTask:
     ldr  r4, =xSecureContext
     str  r1, [r4]                           /* Set xSecureContext to this task's value for the same. */
     msr  psplim, r2                         /* Set this task's PSPLIM value. */
-    movs r1, #2                             /* r1 = 2. */
+    mrs  r1, control                        /* Obtain current control register value. */
-    msr  CONTROL, r1                        /* Switch to use PSP in the thread mode. */
+    orrs r1, r1, #2                         /* r1 = r1 | 0x2 - Set the second bit to use the program stack pointe (PSP). */
+    msr control, r1                         /* Write back the new control register value. */
     adds r0, #32                            /* Discard everything up to r0. */
     msr  psp, r0                            /* This is now the new top of stack to use in the task. */
     isb

portable/IAR/ARM_CM85/non_secure/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -56,6 +58,7 @@
 #define portARCH_NAME                    "Cortex-M85"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         1
+#define portHAS_PACBTI_FEATURE           1
 #define portDONT_DISCARD                 __root
 /*-----------------------------------------------------------*/
 

portable/IAR/ARM_CM85_NTZ/non_secure/port.c

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -110,6 +112,7 @@ typedef void ( * portISR_t )( void );
 #define portSCB_VTOR_REG                      ( *( ( portISR_t ** ) 0xe000ed08 ) )
 #define portSCB_SYS_HANDLER_CTRL_STATE_REG    ( *( ( volatile uint32_t * ) 0xe000ed24 ) )
 #define portSCB_MEM_FAULT_ENABLE_BIT          ( 1UL << 16UL )
+#define portSCB_USG_FAULT_ENABLE_BIT          ( 1UL << 18UL )
 /*-----------------------------------------------------------*/
 
 /**
@@ -373,6 +376,20 @@ typedef void ( * portISR_t )( void );
  * any secure calls.
  */
 #define portNO_SECURE_CONTEXT    0
+
+/**
+ * @brief Constants required to check and configure PACBTI security feature implementation.
+ */
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    #define portID_ISAR5_REG         ( *( ( volatile uint32_t * ) 0xe000ed74 ) )
+
+    #define portCONTROL_UPAC_EN      ( 1UL << 7UL )
+    #define portCONTROL_PAC_EN       ( 1UL << 6UL )
+    #define portCONTROL_UBTI_EN      ( 1UL << 5UL )
+    #define portCONTROL_BTI_EN       ( 1UL << 4UL )
+
+#endif /* portHAS_PACBTI_FEATURE */
 /*-----------------------------------------------------------*/
 
 /**
@@ -410,6 +427,26 @@ static void prvTaskExitError( void );
     static void prvSetupFPU( void ) PRIVILEGED_FUNCTION;
 #endif /* configENABLE_FPU */
 
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+/**
+ * @brief Configures PACBTI features.
+ *
+ * This function configures the Pointer Authentication, and Branch Target
+ * Identification security features as per the user configuration. It returns
+ * the value of the special purpose CONTROL register accordingly, and optionally
+ * updates the CONTROL register value. Currently, only Cortex-M85 (ARMv8.1-M
+ * architecture based) target supports PACBTI security feature.
+ *
+ * @param xWriteControlRegister Used to control whether the special purpose
+ * CONTROL register should be updated or not.
+ *
+ * @return CONTROL register value according to the configured PACBTI option.
+ */
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister );
+
+#endif /* portHAS_PACBTI_FEATURE */
+
 /**
  * @brief Setup the timer to generate the tick interrupts.
  *
@@ -1457,6 +1494,7 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
                                          xMPU_SETTINGS * xMPUSettings ) /* PRIVILEGED_FUNCTION */
     {
         uint32_t ulIndex = 0;
+        uint32_t ulControl = 0x0;
 
         xMPUSettings->ulContext[ ulIndex ] = 0x04040404; /* r4. */
         ulIndex++;
@@ -1503,16 +1541,24 @@ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTIO
         xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) pxEndOfStack;         /* PSPLIM. */
         ulIndex++;
 
+        #if ( portHAS_PACBTI_FEATURE == 1 )
+        {
+            /* Check PACBTI security feature configuration before pushing the
+             * CONTROL register's value on task's TCB. */
+            ulControl = prvConfigurePACBTI( pdFALSE );
+        }
+        #endif /* portHAS_PACBTI_FEATURE */
+
         if( xRunPrivileged == pdTRUE )
         {
             xMPUSettings->ulTaskFlags |= portTASK_IS_PRIVILEGED_FLAG;
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
         else
         {
             xMPUSettings->ulTaskFlags &= ( ~portTASK_IS_PRIVILEGED_FLAG );
-            xMPUSettings->ulContext[ ulIndex ] = ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED; /* CONTROL. */
+            xMPUSettings->ulContext[ ulIndex ] = ( ulControl | ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED ); /* CONTROL. */
             ulIndex++;
         }
 
@@ -1740,6 +1786,14 @@ BaseType_t xPortStartScheduler( void ) /* PRIVILEGED_FUNCTION */
     portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
     portNVIC_SHPR2_REG = 0;
 
+    #if ( portHAS_PACBTI_FEATURE == 1 )
+    {
+        /* Set the CONTROL register value based on PACBTI security feature
+         * configuration before starting the first task. */
+        ( void) prvConfigurePACBTI( pdTRUE );
+    }
+    #endif /* portHAS_PACBTI_FEATURE */
+
     #if ( configENABLE_MPU == 1 )
     {
         /* Setup the Memory Protection Unit (MPU). */
@@ -2158,3 +2212,42 @@ BaseType_t xPortIsInsideInterrupt( void )
 
 #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */
 /*-----------------------------------------------------------*/
+
+#if ( portHAS_PACBTI_FEATURE == 1 )
+
+    static uint32_t prvConfigurePACBTI( BaseType_t xWriteControlRegister )
+    {
+        uint32_t ulControl = 0x0;
+
+        /* Ensure that PACBTI is implemented. */
+        configASSERT( portID_ISAR5_REG != 0x0 );
+
+        /* Enable UsageFault exception if PAC or BTI is enabled. */
+        #if( ( configENABLE_PAC == 1 ) || ( configENABLE_BTI == 1 ) )
+        {
+            portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_USG_FAULT_ENABLE_BIT;
+        }
+        #endif
+
+        #if( configENABLE_PAC == 1 )
+        {
+            ulControl |= ( portCONTROL_UPAC_EN | portCONTROL_PAC_EN );
+        }
+        #endif
+
+        #if( configENABLE_BTI == 1 )
+        {
+            ulControl |= ( portCONTROL_UBTI_EN | portCONTROL_BTI_EN );
+        }
+        #endif
+
+        if( xWriteControlRegister == pdTRUE )
+        {
+            __asm volatile ( "msr control, %0" : : "r" ( ulControl ) );
+        }
+
+        return ulControl;
+    }
+
+#endif /* #if ( portHAS_PACBTI_FEATURE == 1 ) */
+/*-----------------------------------------------------------*/

portable/IAR/ARM_CM85_NTZ/non_secure/portasm.s

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -165,8 +167,9 @@ vRestoreContextOfFirstTask:
 
     ldm  r0!, {r1-r2}                       /* Read from stack - r1 = PSPLIM and r2 = EXC_RETURN. */
     msr  psplim, r1                         /* Set this task's PSPLIM value. */
-    movs r1, #2                             /* r1 = 2. */
+    mrs  r1, control                        /* Obtain current control register value. */
-    msr  CONTROL, r1                        /* Switch to use PSP in the thread mode. */
+    orrs r1, r1, #2                         /* r1 = r1 | 0x2 - Set the second bit to use the program stack pointe (PSP). */
+    msr control, r1                         /* Write back the new control register value. */
     adds r0, #32                            /* Discard everything up to r0. */
     msr  psp, r0                            /* This is now the new top of stack to use in the task. */
     isb

portable/IAR/ARM_CM85_NTZ/non_secure/portmacro.h

@@ -1,6 +1,8 @@
 /*
  * FreeRTOS Kernel <DEVELOPMENT BRANCH>
  * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * Copyright 2024 Arm Limited and/or its affiliates
+ * <open-source-office@arm.com>
  *
  * SPDX-License-Identifier: MIT
  *
@@ -56,6 +58,7 @@
 #define portARCH_NAME                    "Cortex-M85"
 #define portHAS_ARMV8M_MAIN_EXTENSION    1
 #define portARMV8M_MINOR_VERSION         1
+#define portHAS_PACBTI_FEATURE           1
 #define portDONT_DISCARD                 __root
 /*-----------------------------------------------------------*/