Update Cortex-M3 and Cortex-M4F ports to allow the SysTick to be clocked at a differe...

[freertos] / FreeRTOS / Source / portable / IAR / ARM_CM4F / port.c

diff --git a/FreeRTOS/Source/portable/IAR/ARM_CM4F/port.c b/FreeRTOS/Source/portable/IAR/ARM_CM4F/port.c
index 95b8b1870c58583aabb76fa33e27d46586a73ad4..7c287649e1388516aeabe80c5048dc79b87b4db4 100644 (file)
--- a/FreeRTOS/Source/portable/IAR/ARM_CM4F/port.c
+++ b/FreeRTOS/Source/portable/IAR/ARM_CM4F/port.c
@@ -383,7 +383,7 @@ void xPortSysTickHandler( void )
 \r
        __weak void vPortSuppressTicksAndSleep( portTickType xExpectedIdleTime )\r
        {\r
-       unsigned long ulReloadValue, ulCompleteTickPeriods, ulCompletedSysTickDecrements;\r
+       unsigned long ulReloadValue, ulCompleteTickPeriods, ulCompletedSysTickDecrements, ulSysTickCTRL;\r
        portTickType xModifiableIdleTime;\r
 \r
                /* Make sure the SysTick reload value does not overflow the counter. */\r
@@ -396,7 +396,7 @@ void xPortSysTickHandler( void )
                is accounted for as best it can be, but using the tickless mode will\r
                inevitably result in some tiny drift of the time maintained by the\r
                kernel with respect to calendar time. */\r
-               portNVIC_SYSTICK_CTRL_REG = portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT;\r
+               portNVIC_SYSTICK_CTRL_REG &= ~portNVIC_SYSTICK_ENABLE_BIT;\r
 \r
                /* Calculate the reload value required to wait xExpectedIdleTime\r
                tick periods.  -1 is used because this code will execute part way\r
@@ -420,7 +420,7 @@ void xPortSysTickHandler( void )
                        portNVIC_SYSTICK_LOAD_REG = portNVIC_SYSTICK_CURRENT_VALUE_REG;\r
 \r
                        /* Restart SysTick. */\r
-                       portNVIC_SYSTICK_CTRL_REG = portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT | portNVIC_SYSTICK_ENABLE_BIT;\r
+                       portNVIC_SYSTICK_CTRL_REG |= portNVIC_SYSTICK_ENABLE_BIT;\r
 \r
                        /* Reset the reload register to the value required for normal tick\r
                        periods. */\r
@@ -440,7 +440,7 @@ void xPortSysTickHandler( void )
                        portNVIC_SYSTICK_CURRENT_VALUE_REG = 0UL;\r
 \r
                        /* Restart SysTick. */\r
-                       portNVIC_SYSTICK_CTRL_REG = portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT | portNVIC_SYSTICK_ENABLE_BIT;\r
+                       portNVIC_SYSTICK_CTRL_REG |= portNVIC_SYSTICK_ENABLE_BIT;\r
 \r
                        /* Sleep until something happens.  configPRE_SLEEP_PROCESSING() can\r
                        set its parameter to 0 to indicate that its implementation contains\r
@@ -461,13 +461,14 @@ void xPortSysTickHandler( void )
                        accounted for as best it can be, but using the tickless mode will\r
                        inevitably result in some tiny drift of the time maintained by the\r
                        kernel with respect to calendar time. */\r
-                       portNVIC_SYSTICK_CTRL_REG = portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT;\r
+                       ulSysTickCTRL = portNVIC_SYSTICK_CTRL_REG;\r
+                       portNVIC_SYSTICK_CTRL_REG = ( ulSysTickCTRL & ~portNVIC_SYSTICK_ENABLE_BIT );\r
 \r
                        /* Re-enable interrupts - see comments above __disable_interrupt()\r
                        call above. */\r
                        __enable_interrupt();\r
 \r
-                       if( ( portNVIC_SYSTICK_CTRL_REG & portNVIC_SYSTICK_COUNT_FLAG_BIT ) != 0 )\r
+                       if( ( ulSysTickCTRL & portNVIC_SYSTICK_COUNT_FLAG_BIT ) != 0 )\r
                        {\r
                                unsigned long ulCalculatedLoadValue;\r
 \r
@@ -519,7 +520,7 @@ void xPortSysTickHandler( void )
                        portNVIC_SYSTICK_CURRENT_VALUE_REG = 0UL;\r
                        portENTER_CRITICAL();\r
                        {\r
-                               portNVIC_SYSTICK_CTRL_REG = portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT | portNVIC_SYSTICK_ENABLE_BIT;\r
+                               portNVIC_SYSTICK_CTRL_REG |= portNVIC_SYSTICK_ENABLE_BIT;\r
                                vTaskStepTick( ulCompleteTickPeriods );\r
                                portNVIC_SYSTICK_LOAD_REG = ulTimerCountsForOneTick - 1UL;\r
                        }\r
@@ -547,7 +548,7 @@ __weak void vPortSetupTimerInterrupt( void )
 \r
        /* Configure SysTick to interrupt at the requested rate. */\r
        portNVIC_SYSTICK_LOAD_REG = ( configSYSTICK_CLOCK_HZ / configTICK_RATE_HZ ) - 1UL;;\r
-       portNVIC_SYSTICK_CTRL_REG = portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT | portNVIC_SYSTICK_ENABLE_BIT;\r
+       portNVIC_SYSTICK_CTRL_REG |= ( portNVIC_SYSTICK_INT_BIT | portNVIC_SYSTICK_ENABLE_BIT );\r
 }\r
 /*-----------------------------------------------------------*/\r
 \r