Add symbol needed for OpenOCD to detect FreeRTOS, add feature to break execution when the scheduler is initially started.

components/freertos/Kconfig

@@ -121,5 +121,12 @@ config FREERTOS_DEBUG_OCDAWARE
 		The FreeRTOS panic and unhandled exception handers can detect a JTAG OCD debugger and
 		instead of panicking, have the debugger stop on the offending instruction.
 
+config FREERTOS_BREAK_ON_SCHEDULER_START_JTAG
+	bool "Stop program on scheduler start when JTAG/OCD is detected"
+	depends on FREERTOS_DEBUG_OCDAWARE
+	default y
+	help
+		If JTAG/OCD is connected, stop execution when the scheduler is started and the first
+		task is executed.
 
 endmenu

components/freertos/Makefile

@@ -2,6 +2,7 @@
 # Component Makefile
 #
 
+COMPONENT_ADD_LDFLAGS = -l$(COMPONENT_NAME) -Wl,--undefined=uxTopUsedPriority
 COMPONENT_ADD_INCLUDEDIRS := include
 COMPONENT_PRIV_INCLUDEDIRS := include/freertos
 

components/freertos/include/freertos/FreeRTOSConfig.h

@@ -128,6 +128,8 @@
  * FreeRTOS API DOCUMENTATION AVAILABLE ON THE FreeRTOS.org WEB SITE. 
  *----------------------------------------------------------*/
 
+
+
 #define configUSE_PREEMPTION			1
 #define configUSE_IDLE_HOOK				0
 

components/freertos/include/freertos/portmacro.h

@@ -118,8 +118,11 @@ typedef unsigned portBASE_TYPE	UBaseType_t;
 // portbenchmark
 #include "portbenchmark.h"
 
+#include "sdkconfig.h"
 
 #define portMUX_DEBUG
+#define portFIRST_TASK_HOOK CONFIG_FREERTOS_BREAK_ON_SCHEDULER_START_JTAG
+
 
 typedef struct {
 	volatile uint32_t mux;

components/freertos/panic.c

@@ -142,6 +142,17 @@ void panicHandler(XtExcFrame *frame) {
 	commonErrorHandler(frame);
 }
 
+static void setFirstBreakpoint(uint32_t pc) {
+	asm(
+		"wsr.ibreaka0 %0\n" \
+		"rsr.ibreakenable a3\n" \
+		"movi a4,1\n" \
+		"or a4, a4, a3\n" \
+		"wsr.ibreakenable a4\n" \
+		::"r"(pc):"a3","a4");
+	return;
+}
+
 void xt_unhandled_exception(XtExcFrame *frame) {
 	int *regs=(int*)frame;
 	int x;
@@ -158,14 +169,7 @@ void xt_unhandled_exception(XtExcFrame *frame) {
 		panicPutStr(". Setting bp and returning..\r\n");
 		//Stick a hardware breakpoint on the address the handler returns to. This way, the OCD debugger
 		//will kick in exactly at the context the error happened.
-		asm(
+		setFirstBreakpoint(regs[1]);
-			"wsr.ibreaka0 %0\n" \
-			"rsr.ibreakenable a3\n" \
-			"movi a4,1\n" \
-			"or a4, a4, a3\n" \
-			"wsr.ibreakenable a4\n" \
-			::"r"(regs[1]):"a3","a4");
-		return;
 	}
 	panicPutStr(". Exception was unhandled.\r\n");
 	commonErrorHandler(frame);
@@ -209,3 +213,9 @@ void commonErrorHandler(XtExcFrame *frame) {
 	while(1);
 #endif
 }
+
+
+void setBreakpointIfJtag(void *fn) {
+	if (!inOCDMode()) return;
+	setFirstBreakpoint((uint32_t)fn);
+}

components/freertos/port.c

@@ -101,6 +101,8 @@
 #include "FreeRTOS.h"
 #include "task.h"
 
+#include "panic.h"
+
 /* Defined in portasm.h */
 extern void _frxt_tick_timer_init(void);
 
@@ -385,6 +387,10 @@ portBASE_TYPE vPortCPUReleaseMutex(portMUX_TYPE *mux) {
 	return ret;
 }
 
-
+#if CONFIG_FREERTOS_BREAK_ON_SCHEDULER_START_JTAG
+void vPortFirstTaskHook(TaskFunction_t function) {
+	setBreakpointIfJtag(function);
+}
+#endif
 
 

components/freertos/tasks.c

@@ -445,6 +445,11 @@ to its original value when it is released. */
 	extern void vApplicationTickHook( void );
 #endif
 
+#if  portFIRST_TASK_HOOK
+	extern void vPortFirstTaskHook(TaskFunction_t taskfn);
+#endif
+
+
 /* File private functions. --------------------------------*/
 
 /*
@@ -707,6 +712,12 @@ BaseType_t i;
 						/* Schedule if nothing is scheduled yet, or overwrite a task of lower prio. */
 						if ( pxCurrentTCB[i] == NULL || pxCurrentTCB[i]->uxPriority <= uxPriority )
 						{
+#if portFIRST_TASK_HOOK
+							if ( i == 0) {
+								vPortFirstTaskHook(pxTaskCode);
+							}
+#endif /* configFIRST_TASK_HOOK */
+
 							pxCurrentTCB[i] = pxNewTCB;
 							break;
 						}