Replace the static prvSetupTimerInterrupt() function in the Cortex-M port layers...

[freertos] / FreeRTOS / Source / portable / RVDS / ARM_CM0 / port.c

diff --git a/FreeRTOS/Source/portable/RVDS/ARM_CM0/port.c b/FreeRTOS/Source/portable/RVDS/ARM_CM0/port.c
index 8282984b507a06e5c83bf6c7f318c36550d0126f..be659fd4f49b3a11bae389cd9c0e16783120d12c 100644 (file)
--- a/FreeRTOS/Source/portable/RVDS/ARM_CM0/port.c
+++ b/FreeRTOS/Source/portable/RVDS/ARM_CM0/port.c
@@ -64,6 +64,15 @@
 /* Constants used with memory barrier intrinsics. */\r
 #define portSY_FULL_READ_WRITE         ( 15 )\r
 \r
+/* Legacy macro for backward compatibility only.  This macro used to be used to\r
+replace the function that configures the clock used to generate the tick\r
+interrupt (prvSetupTimerInterrupt()), but now the function is declared weak so\r
+the application writer can override it by simply defining a function of the\r
+same name (vApplicationSetupTickInterrupt()). */\r
+#ifndef configOVERRIDE_DEFAULT_TICK_CONFIGURATION\r
+       #define configOVERRIDE_DEFAULT_TICK_CONFIGURATION 0\r
+#endif\r
+\r
 /* Each task maintains its own interrupt status in the critical nesting\r
 variable. */\r
 static UBaseType_t uxCriticalNesting = 0xaaaaaaaa;\r
@@ -87,9 +96,11 @@ static UBaseType_t uxCriticalNesting = 0xaaaaaaaa;
 #endif /* configUSE_TICKLESS_IDLE */\r
 \r
 /*\r
- * Setup the timer to generate the tick interrupts.\r
+ * Setup the timer to generate the tick interrupts.  The implementation in this\r
+ * file is weak to allow application writers to change the timer used to\r
+ * generate the tick interrupt.\r
  */\r
-static void prvSetupTimerInterrupt( void );\r
+void vPortSetupTimerInterrupt( void );\r
 \r
 /*\r
  * Exception handlers.\r
@@ -192,7 +203,7 @@ BaseType_t xPortStartScheduler( void )
 \r
        /* Start the timer that generates the tick ISR.  Interrupts are disabled\r
        here already. */\r
-       prvSetupTimerInterrupt();\r
+       vPortSetupTimerInterrupt();\r
 \r
        /* Initialise the critical nesting count ready for the first task. */\r
        uxCriticalNesting = 0;\r
@@ -327,23 +338,27 @@ uint32_t ulPreviousMask;
  * Setup the systick timer to generate the tick interrupts at the required\r
  * frequency.\r
  */\r
-void prvSetupTimerInterrupt( void )\r
-{\r
-       /* Calculate the constants required to configure the tick interrupt. */\r
-       #if( configUSE_TICKLESS_IDLE == 1 )\r
-               ulTimerCountsForOneTick = ( configCPU_CLOCK_HZ / configTICK_RATE_HZ );\r
-               xMaximumPossibleSuppressedTicks = portMAX_24_BIT_NUMBER / ulTimerCountsForOneTick;\r
-               ulStoppedTimerCompensation = portMISSED_COUNTS_FACTOR;\r
-       #endif /* configUSE_TICKLESS_IDLE */\r
-\r
-       /* Stop and reset the SysTick. */\r
-       portNVIC_SYSTICK_CTRL_REG = 0UL;\r
-       portNVIC_SYSTICK_CURRENT_VALUE_REG = 0UL;\r
-\r
-       /* Configure SysTick to interrupt at the requested rate. */\r
-       portNVIC_SYSTICK_LOAD_REG = ( configCPU_CLOCK_HZ / configTICK_RATE_HZ ) - 1UL;\r
-       portNVIC_SYSTICK_CTRL_REG = portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT | portNVIC_SYSTICK_ENABLE_BIT;\r
-}\r
+#if( configOVERRIDE_DEFAULT_TICK_CONFIGURATION == 0 )\r
+\r
+       __weak void vPortSetupTimerInterrupt( void )\r
+       {\r
+               /* Calculate the constants required to configure the tick interrupt. */\r
+               #if( configUSE_TICKLESS_IDLE == 1 )\r
+                       ulTimerCountsForOneTick = ( configCPU_CLOCK_HZ / configTICK_RATE_HZ );\r
+                       xMaximumPossibleSuppressedTicks = portMAX_24_BIT_NUMBER / ulTimerCountsForOneTick;\r
+                       ulStoppedTimerCompensation = portMISSED_COUNTS_FACTOR;\r
+               #endif /* configUSE_TICKLESS_IDLE */\r
+\r
+               /* Stop and reset the SysTick. */\r
+               portNVIC_SYSTICK_CTRL_REG = 0UL;\r
+               portNVIC_SYSTICK_CURRENT_VALUE_REG = 0UL;\r
+\r
+               /* Configure SysTick to interrupt at the requested rate. */\r
+               portNVIC_SYSTICK_LOAD_REG = ( configCPU_CLOCK_HZ / configTICK_RATE_HZ ) - 1UL;\r
+               portNVIC_SYSTICK_CTRL_REG = portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT | portNVIC_SYSTICK_ENABLE_BIT;\r
+       }\r
+\r
+#endif /* configOVERRIDE_DEFAULT_TICK_CONFIGURATION */\r
 /*-----------------------------------------------------------*/\r
 \r
 #if( configUSE_TICKLESS_IDLE == 1 )\r