Add code to assert() if non ISR safe API function is called from ISR in Tasking CM4F ports - plus fix bug where the max syscall interrupt priority was used incorrectly in the Tasking CM4F port.

FreeRTOS/Source/portable/Tasking/ARM_CM4F/port.c

@@ -81,6 +81,9 @@
 #define portNVIC_PENDSV_PRI			( ( ( uint32_t ) configKERNEL_INTERRUPT_PRIORITY ) << 16 )
 #define portNVIC_SYSTICK_PRI		( ( ( uint32_t ) configKERNEL_INTERRUPT_PRIORITY ) << 24 )
 
+/* Masks off all bits but the VECTACTIVE bits in the ICSR register. */
+#define portVECTACTIVE_MASK					( 0x1FUL )
+
 /* Constants required to manipulate the VFP. */
 #define portFPCCR					( ( volatile uint32_t * ) 0xe000ef34 ) /* Floating point context control register. */
 #define portASPEN_AND_LSPEN_BITS	( 0x3UL << 30UL )
@@ -240,6 +243,16 @@ void vPortEnterCritical( void )
 	ulCriticalNesting++;
 	__DSB();
 	__ISB();
+
+	/* 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( ( ( *(portNVIC_INT_CTRL) ) & portVECTACTIVE_MASK ) == 0 );
+	}
 }
 /*-----------------------------------------------------------*/
 

FreeRTOS/Source/portable/Tasking/ARM_CM4F/port_asm.asm

@@ -92,6 +92,7 @@ _vector_14: .type func
 
 	stmdb sp!, {r3}
 	ldr.w r0, =ulMaxSyscallInterruptPriorityConst
+	ldr r0, [r0]
 	msr basepri, r0
 	bl vTaskSwitchContext
 	mov r0, #0
@@ -146,6 +147,7 @@ _lc_ref__vector_pp_14: .type func
 
 	stmdb sp!, {r3}
 	ldr.w r0, =ulMaxSyscallInterruptPriorityConst
+	ldr r0, [r0]
 	msr basepri, r0
 	bl vTaskSwitchContext
 	mov r0, #0
@@ -206,6 +208,7 @@ vPortStartFirstTask .type func
 	msr msp, r0
 	;Call SVC to start the first task.
 	cpsie i
+	cpsie f
 	dsb
 	isb
 	svc 0
@@ -237,6 +240,7 @@ vPortEnableVFP .type func
 ulPortSetInterruptMask:
 	mrs r0, basepri
 	ldr.w r1, =ulMaxSyscallInterruptPriorityConst
+	ldr r1, [r1]
 	msr basepri, r1
 	bx r14
 	.size	ulPortSetInterruptMask, $-ulPortSetInterruptMask