From ed6ec5c73f60aed9f12f6e81031a544f042c4cd8 Mon Sep 17 00:00:00 2001 From: Erick Reyes Date: Tue, 18 Mar 2025 23:42:49 -0700 Subject: [PATCH] FreeRTOS MPU: allow user control on CM55 devices with 16 MPU regions Remove the assertion that forces the application to match configTOTAL_MPU_REGIONS with the number of regions present in the hardware. This allows applications running on devices with 16 MPU regions to control the second half, while the kernel retains control of the first. Signed-off-by: Erick Reyes --- portable/GCC/ARM_CM55_NTZ/non_secure/port.c | 100 +++++++++----------- 1 file changed, 45 insertions(+), 55 deletions(-) diff --git a/portable/GCC/ARM_CM55_NTZ/non_secure/port.c b/portable/GCC/ARM_CM55_NTZ/non_secure/port.c index b2fd7e518..3f7b9a922 100644 --- a/portable/GCC/ARM_CM55_NTZ/non_secure/port.c +++ b/portable/GCC/ARM_CM55_NTZ/non_secure/port.c @@ -241,9 +241,6 @@ typedef void ( * portISR_t )( void ); /* Enable MPU. */ #define portMPU_ENABLE_BIT ( 1UL << 0UL ) -/* Expected value of the portMPU_TYPE register. */ -#define portEXPECTED_MPU_TYPE_VALUE ( configTOTAL_MPU_REGIONS << 8UL ) - /* Extract first address of the MPU region as encoded in the * RBAR (Region Base Address Register) value. */ #define portEXTRACT_FIRST_ADDRESS_FROM_RBAR( rbar ) \ @@ -925,64 +922,57 @@ static void prvTaskExitError( void ) /* The only permitted number of regions are 8 or 16. */ configASSERT( ( configTOTAL_MPU_REGIONS == 8 ) || ( configTOTAL_MPU_REGIONS == 16 ) ); - /* Ensure that the configTOTAL_MPU_REGIONS is configured correctly. */ - configASSERT( portMPU_TYPE_REG == portEXPECTED_MPU_TYPE_VALUE ); + /* MAIR0 - Index 0. */ + portMPU_MAIR0_REG |= ( ( portMPU_NORMAL_MEMORY_BUFFERABLE_CACHEABLE << portMPU_MAIR_ATTR0_POS ) & portMPU_MAIR_ATTR0_MASK ); + /* MAIR0 - Index 1. */ + portMPU_MAIR0_REG |= ( ( portMPU_DEVICE_MEMORY_nGnRE << portMPU_MAIR_ATTR1_POS ) & portMPU_MAIR_ATTR1_MASK ); - /* Check that the MPU is present. */ - if( portMPU_TYPE_REG == portEXPECTED_MPU_TYPE_VALUE ) - { - /* MAIR0 - Index 0. */ - portMPU_MAIR0_REG |= ( ( portMPU_NORMAL_MEMORY_BUFFERABLE_CACHEABLE << portMPU_MAIR_ATTR0_POS ) & portMPU_MAIR_ATTR0_MASK ); - /* MAIR0 - Index 1. */ - portMPU_MAIR0_REG |= ( ( portMPU_DEVICE_MEMORY_nGnRE << portMPU_MAIR_ATTR1_POS ) & portMPU_MAIR_ATTR1_MASK ); + /* Setup privileged flash as Read Only so that privileged tasks can + * read it but not modify. */ + portMPU_RNR_REG = portPRIVILEGED_FLASH_REGION; + portMPU_RBAR_REG = ( ( ( uint32_t ) __privileged_functions_start__ ) & portMPU_RBAR_ADDRESS_MASK ) | + ( portMPU_REGION_NON_SHAREABLE ) | + ( portMPU_REGION_PRIVILEGED_READ_ONLY ); + portMPU_RLAR_REG = ( ( ( uint32_t ) __privileged_functions_end__ ) & portMPU_RLAR_ADDRESS_MASK ) | + ( portMPU_RLAR_ATTR_INDEX0 ) | + ( portMPU_RLAR_REGION_ENABLE ); - /* Setup privileged flash as Read Only so that privileged tasks can - * read it but not modify. */ - portMPU_RNR_REG = portPRIVILEGED_FLASH_REGION; - portMPU_RBAR_REG = ( ( ( uint32_t ) __privileged_functions_start__ ) & portMPU_RBAR_ADDRESS_MASK ) | - ( portMPU_REGION_NON_SHAREABLE ) | - ( portMPU_REGION_PRIVILEGED_READ_ONLY ); - portMPU_RLAR_REG = ( ( ( uint32_t ) __privileged_functions_end__ ) & portMPU_RLAR_ADDRESS_MASK ) | - ( portMPU_RLAR_ATTR_INDEX0 ) | - ( portMPU_RLAR_REGION_ENABLE ); + /* Setup unprivileged flash as Read Only by both privileged and + * unprivileged tasks. All tasks can read it but no-one can modify. */ + portMPU_RNR_REG = portUNPRIVILEGED_FLASH_REGION; + portMPU_RBAR_REG = ( ( ( uint32_t ) __unprivileged_flash_start__ ) & portMPU_RBAR_ADDRESS_MASK ) | + ( portMPU_REGION_NON_SHAREABLE ) | + ( portMPU_REGION_READ_ONLY ); + portMPU_RLAR_REG = ( ( ( uint32_t ) __unprivileged_flash_end__ ) & portMPU_RLAR_ADDRESS_MASK ) | + ( portMPU_RLAR_ATTR_INDEX0 ) | + ( portMPU_RLAR_REGION_ENABLE ); - /* Setup unprivileged flash as Read Only by both privileged and - * unprivileged tasks. All tasks can read it but no-one can modify. */ - portMPU_RNR_REG = portUNPRIVILEGED_FLASH_REGION; - portMPU_RBAR_REG = ( ( ( uint32_t ) __unprivileged_flash_start__ ) & portMPU_RBAR_ADDRESS_MASK ) | - ( portMPU_REGION_NON_SHAREABLE ) | - ( portMPU_REGION_READ_ONLY ); - portMPU_RLAR_REG = ( ( ( uint32_t ) __unprivileged_flash_end__ ) & portMPU_RLAR_ADDRESS_MASK ) | - ( portMPU_RLAR_ATTR_INDEX0 ) | - ( portMPU_RLAR_REGION_ENABLE ); + /* Setup unprivileged syscalls flash as Read Only by both privileged + * and unprivileged tasks. All tasks can read it but no-one can modify. */ + portMPU_RNR_REG = portUNPRIVILEGED_SYSCALLS_REGION; + portMPU_RBAR_REG = ( ( ( uint32_t ) __syscalls_flash_start__ ) & portMPU_RBAR_ADDRESS_MASK ) | + ( portMPU_REGION_NON_SHAREABLE ) | + ( portMPU_REGION_READ_ONLY ); + portMPU_RLAR_REG = ( ( ( uint32_t ) __syscalls_flash_end__ ) & portMPU_RLAR_ADDRESS_MASK ) | + ( portMPU_RLAR_ATTR_INDEX0 ) | + ( portMPU_RLAR_REGION_ENABLE ); - /* Setup unprivileged syscalls flash as Read Only by both privileged - * and unprivileged tasks. All tasks can read it but no-one can modify. */ - portMPU_RNR_REG = portUNPRIVILEGED_SYSCALLS_REGION; - portMPU_RBAR_REG = ( ( ( uint32_t ) __syscalls_flash_start__ ) & portMPU_RBAR_ADDRESS_MASK ) | - ( portMPU_REGION_NON_SHAREABLE ) | - ( portMPU_REGION_READ_ONLY ); - portMPU_RLAR_REG = ( ( ( uint32_t ) __syscalls_flash_end__ ) & portMPU_RLAR_ADDRESS_MASK ) | - ( portMPU_RLAR_ATTR_INDEX0 ) | - ( portMPU_RLAR_REGION_ENABLE ); + /* Setup RAM containing kernel data for privileged access only. */ + portMPU_RNR_REG = portPRIVILEGED_RAM_REGION; + portMPU_RBAR_REG = ( ( ( uint32_t ) __privileged_sram_start__ ) & portMPU_RBAR_ADDRESS_MASK ) | + ( portMPU_REGION_NON_SHAREABLE ) | + ( portMPU_REGION_PRIVILEGED_READ_WRITE ) | + ( portMPU_REGION_EXECUTE_NEVER ); + portMPU_RLAR_REG = ( ( ( uint32_t ) __privileged_sram_end__ ) & portMPU_RLAR_ADDRESS_MASK ) | + ( portMPU_RLAR_ATTR_INDEX0 ) | + ( portMPU_RLAR_REGION_ENABLE ); - /* Setup RAM containing kernel data for privileged access only. */ - portMPU_RNR_REG = portPRIVILEGED_RAM_REGION; - portMPU_RBAR_REG = ( ( ( uint32_t ) __privileged_sram_start__ ) & portMPU_RBAR_ADDRESS_MASK ) | - ( portMPU_REGION_NON_SHAREABLE ) | - ( portMPU_REGION_PRIVILEGED_READ_WRITE ) | - ( portMPU_REGION_EXECUTE_NEVER ); - portMPU_RLAR_REG = ( ( ( uint32_t ) __privileged_sram_end__ ) & portMPU_RLAR_ADDRESS_MASK ) | - ( portMPU_RLAR_ATTR_INDEX0 ) | - ( portMPU_RLAR_REGION_ENABLE ); + /* Enable mem fault. */ + portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_MEM_FAULT_ENABLE_BIT; - /* Enable mem fault. */ - portSCB_SYS_HANDLER_CTRL_STATE_REG |= portSCB_MEM_FAULT_ENABLE_BIT; - - /* Enable MPU with privileged background access i.e. unmapped - * regions have privileged access. */ - portMPU_CTRL_REG |= ( portMPU_PRIV_BACKGROUND_ENABLE_BIT | portMPU_ENABLE_BIT ); - } + /* Enable MPU with privileged background access i.e. unmapped + * regions have privileged access. */ + portMPU_CTRL_REG |= ( portMPU_PRIV_BACKGROUND_ENABLE_BIT | portMPU_ENABLE_BIT ); } #endif /* configENABLE_MPU */