Demo application related:

+ Update the RZ IAR project so it targets the RZ RSK rather than custom hardware.
+ Update the RZ ARM/DS-5 project so it targets the RZ RSK rather than custom hardware.
+ Updated RX64M demos to use the new iodefine.h naming.

Cortex-A9 port related:
+ Update IAR, ARM and GCC Cortex-A9 port layers to include a 'task exit error' function which is called if a task attempts to incorrectly exit its implementing function.
+ Moved the instruction which switches into system mode out of the restore context macro, as it is only needed when starting the first task.

Core kernel files related:
+ Ensure there are no references to the mutexes held count when mutexes are excluded from the build.

FreeRTOS/Source/portable/RVDS/ARM_CA9/port.c

@@ -198,6 +198,11 @@ mode. */
  */
 extern void vPortRestoreTaskContext( void );
 
+/*
+ * Used to catch tasks that attempt to return from their implementing function.
+ */
+static void prvTaskExitError( void );
+
 /*-----------------------------------------------------------*/
 
 /* A variable is used to keep track of the critical section nesting.  This
@@ -260,7 +265,7 @@ StackType_t *pxPortInitialiseStack( StackType_t *pxTopOfStack, TaskFunction_t px
 	pxTopOfStack--;
 
 	/* Next all the registers other than the stack pointer. */
-	*pxTopOfStack = ( StackType_t ) 0x00000000;	/* R14 */
+	*pxTopOfStack = ( StackType_t ) prvTaskExitError;	/* R14 */
 	pxTopOfStack--;
 	*pxTopOfStack = ( StackType_t ) 0x12121212;	/* R12 */
 	pxTopOfStack--;
@@ -303,6 +308,20 @@ StackType_t *pxPortInitialiseStack( StackType_t *pxTopOfStack, TaskFunction_t px
 }
 /*-----------------------------------------------------------*/
 
+static void prvTaskExitError( void )
+{
+	/* A function that implements a task must not exit or attempt to return to
+	its caller as there is nothing to return to.  If a task wants to exit it
+	should instead call vTaskDelete( NULL ).
+
+	Artificially force an assert() to be triggered if configASSERT() is
+	defined, then stop here so application writers can catch the error. */
+	configASSERT( ulPortInterruptNesting == ~0UL );
+	portDISABLE_INTERRUPTS();
+	for( ;; );
+}
+/*-----------------------------------------------------------*/
+
 BaseType_t xPortStartScheduler( void )
 {
 uint32_t ulAPSR;
@@ -354,6 +373,16 @@ void vPortEnterCritical( void )
 	directly.  Increment ulCriticalNesting to keep a count of how many times
 	portENTER_CRITICAL() has been called. */
 	ulCriticalNesting++;
+
+	/* This is not the interrupt safe version of the enter critical function so
+	assert() if it is being called from an interrupt context.  Only API
+	functions that end in "FromISR" can be used in an interrupt.  Only assert if
+	the critical nesting count is 1 to protect against recursive calls if the
+	assert function also uses a critical section. */
+	if( ulCriticalNesting == 1 )
+	{
+		configASSERT( ulPortInterruptNesting == 0 );
+	}
 }
 /*-----------------------------------------------------------*/
 

FreeRTOS/Source/portable/RVDS/ARM_CA9/portASM.s

@@ -71,7 +71,7 @@
 
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-; SVC handler is used to start the scheduler and yield a task.
+; SVC handler is used to yield a task.
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 FreeRTOS_SWI_Handler
 
@@ -81,10 +81,15 @@ FreeRTOS_SWI_Handler
 	portSAVE_CONTEXT
 	LDR R0, =vTaskSwitchContext
 	BLX	R0
-
-vPortRestoreTaskContext
 	portRESTORE_CONTEXT
 
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+; vPortRestoreTaskContext is used to start the scheduler.
+;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
+vPortRestoreTaskContext
+	; Switch to system mode
+	CPS		#SYS_MODE
+	portRESTORE_CONTEXT
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
 ; PL390 GIC interrupt handler
@@ -132,7 +137,7 @@ FreeRTOS_IRQ_Handler
 	ADD		sp, sp, r2
 
 	CPSID 	i
-	
+
 	; Write the value read from ICCIAR to ICCEOIR
 	LDR 	r4, =ulICCEOIR
 	STR		r0, [r4]

FreeRTOS/Source/portable/RVDS/ARM_CA9/portmacro.inc

@@ -104,9 +104,6 @@ IRQ_MODE			EQU		0x12
 	MACRO
 	portRESTORE_CONTEXT
 
-	; Switch to system mode
-	CPS		#SYS_MODE
-
 	; Set the SP to point to the stack of the task being restored.
 	LDR		R0, =pxCurrentTCB
 	LDR		R1, [R0]