diff options
Diffstat (limited to 'rtos/FreeRTOS/Source/portable/RVDS/ARM_CM4F/port.c')
| -rw-r--r-- | rtos/FreeRTOS/Source/portable/RVDS/ARM_CM4F/port.c | 1562 |
1 files changed, 782 insertions, 780 deletions
diff --git a/rtos/FreeRTOS/Source/portable/RVDS/ARM_CM4F/port.c b/rtos/FreeRTOS/Source/portable/RVDS/ARM_CM4F/port.c index 5d7f4dd..18577f4 100644 --- a/rtos/FreeRTOS/Source/portable/RVDS/ARM_CM4F/port.c +++ b/rtos/FreeRTOS/Source/portable/RVDS/ARM_CM4F/port.c @@ -1,780 +1,782 @@ -/* - FreeRTOS V8.0.0 - Copyright (C) 2014 Real Time Engineers Ltd. - All rights reserved - - VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION. - - *************************************************************************** - * * - * FreeRTOS provides completely free yet professionally developed, * - * robust, strictly quality controlled, supported, and cross * - * platform software that has become a de facto standard. * - * * - * Help yourself get started quickly and support the FreeRTOS * - * project by purchasing a FreeRTOS tutorial book, reference * - * manual, or both from: http://www.FreeRTOS.org/Documentation * - * * - * Thank you! * - * * - *************************************************************************** - - This file is part of the FreeRTOS distribution. - - FreeRTOS is free software; you can redistribute it and/or modify it under - the terms of the GNU General Public License (version 2) as published by the - Free Software Foundation >>!AND MODIFIED BY!<< the FreeRTOS exception. - - >>! NOTE: The modification to the GPL is included to allow you to distribute - >>! a combined work that includes FreeRTOS without being obliged to provide - >>! the source code for proprietary components outside of the FreeRTOS - >>! kernel. - - FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY - WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS - FOR A PARTICULAR PURPOSE. Full license text is available from the following - link: http://www.freertos.org/a00114.html - - 1 tab == 4 spaces! - - *************************************************************************** - * * - * Having a problem? Start by reading the FAQ "My application does * - * not run, what could be wrong?" * - * * - * http://www.FreeRTOS.org/FAQHelp.html * - * * - *************************************************************************** - - http://www.FreeRTOS.org - Documentation, books, training, latest versions, - license and Real Time Engineers Ltd. contact details. - - http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products, - including FreeRTOS+Trace - an indispensable productivity tool, a DOS - compatible FAT file system, and our tiny thread aware UDP/IP stack. - - http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High - Integrity Systems to sell under the OpenRTOS brand. Low cost OpenRTOS - licenses offer ticketed support, indemnification and middleware. - - http://www.SafeRTOS.com - High Integrity Systems also provide a safety - engineered and independently SIL3 certified version for use in safety and - mission critical applications that require provable dependability. - - 1 tab == 4 spaces! -*/ - -/*----------------------------------------------------------- - * Implementation of functions defined in portable.h for the ARM CM4F port. - *----------------------------------------------------------*/ - -/* Scheduler includes. */ -#include "FreeRTOS.h" -#include "task.h" - -#ifndef __TARGET_FPU_VFP - #error This port can only be used when the project options are configured to enable hardware floating point support. -#endif - -#if configMAX_SYSCALL_INTERRUPT_PRIORITY == 0 - #error configMAX_SYSCALL_INTERRUPT_PRIORITY must not be set to 0. See http://www.FreeRTOS.org/RTOS-Cortex-M3-M4.html -#endif - -#ifndef configSYSTICK_CLOCK_HZ - #define configSYSTICK_CLOCK_HZ configCPU_CLOCK_HZ - /* Ensure the SysTick is clocked at the same frequency as the core. */ - #define portNVIC_SYSTICK_CLK_BIT ( 1UL << 2UL ) -#else - /* The way the SysTick is clocked is not modified in case it is not the same - as the core. */ - #define portNVIC_SYSTICK_CLK_BIT ( 0 ) -#endif - -/* The __weak attribute does not work as you might expect with the Keil tools -so the configOVERRIDE_DEFAULT_TICK_CONFIGURATION constant must be set to 1 if -the application writer wants to provide their own implementation of -vPortSetupTimerInterrupt(). Ensure configOVERRIDE_DEFAULT_TICK_CONFIGURATION -is defined. */ -#ifndef configOVERRIDE_DEFAULT_TICK_CONFIGURATION - #define configOVERRIDE_DEFAULT_TICK_CONFIGURATION 0 -#endif - -/* Constants required to manipulate the core. Registers first... */ -#define portNVIC_SYSTICK_CTRL_REG ( * ( ( volatile uint32_t * ) 0xe000e010 ) ) -#define portNVIC_SYSTICK_LOAD_REG ( * ( ( volatile uint32_t * ) 0xe000e014 ) ) -#define portNVIC_SYSTICK_CURRENT_VALUE_REG ( * ( ( volatile uint32_t * ) 0xe000e018 ) ) -#define portNVIC_SYSPRI2_REG ( * ( ( volatile uint32_t * ) 0xe000ed20 ) ) -/* ...then bits in the registers. */ -#define portNVIC_SYSTICK_INT_BIT ( 1UL << 1UL ) -#define portNVIC_SYSTICK_ENABLE_BIT ( 1UL << 0UL ) -#define portNVIC_SYSTICK_COUNT_FLAG_BIT ( 1UL << 16UL ) -#define portNVIC_PENDSVCLEAR_BIT ( 1UL << 27UL ) -#define portNVIC_PEND_SYSTICK_CLEAR_BIT ( 1UL << 25UL ) - -#define portNVIC_PENDSV_PRI ( ( ( uint32_t ) configKERNEL_INTERRUPT_PRIORITY ) << 16UL ) -#define portNVIC_SYSTICK_PRI ( ( ( uint32_t ) configKERNEL_INTERRUPT_PRIORITY ) << 24UL ) - -/* Constants required to check the validity of an interrupt priority. */ -#define portFIRST_USER_INTERRUPT_NUMBER ( 16 ) -#define portNVIC_IP_REGISTERS_OFFSET_16 ( 0xE000E3F0 ) -#define portAIRCR_REG ( * ( ( volatile uint32_t * ) 0xE000ED0C ) ) -#define portMAX_8_BIT_VALUE ( ( uint8_t ) 0xff ) -#define portTOP_BIT_OF_BYTE ( ( uint8_t ) 0x80 ) -#define portMAX_PRIGROUP_BITS ( ( uint8_t ) 7 ) -#define portPRIORITY_GROUP_MASK ( 0x07UL << 8UL ) -#define portPRIGROUP_SHIFT ( 8UL ) - -/* Constants required to manipulate the VFP. */ -#define portFPCCR ( ( volatile uint32_t * ) 0xe000ef34 ) /* Floating point context control register. */ -#define portASPEN_AND_LSPEN_BITS ( 0x3UL << 30UL ) - -/* Constants required to set up the initial stack. */ -#define portINITIAL_XPSR ( 0x01000000 ) -#define portINITIAL_EXEC_RETURN ( 0xfffffffd ) - -/* Constants used with memory barrier intrinsics. */ -#define portSY_FULL_READ_WRITE ( 15 ) - -/* The systick is a 24-bit counter. */ -#define portMAX_24_BIT_NUMBER ( 0xffffffUL ) - -/* A fiddle factor to estimate the number of SysTick counts that would have -occurred while the SysTick counter is stopped during tickless idle -calculations. */ -#define portMISSED_COUNTS_FACTOR ( 45UL ) - -/* Each task maintains its own interrupt status in the critical nesting -variable. */ -static UBaseType_t uxCriticalNesting = 0xaaaaaaaa; - -/* - * Setup the timer to generate the tick interrupts. The implementation in this - * file is weak to allow application writers to change the timer used to - * generate the tick interrupt. - */ -void vPortSetupTimerInterrupt( void ); - -/* - * Exception handlers. - */ -void xPortPendSVHandler( void ); -void xPortSysTickHandler( void ); -void vPortSVCHandler( void ); - -/* - * Start first task is a separate function so it can be tested in isolation. - */ -static void prvStartFirstTask( void ); - -/* - * Functions defined in portasm.s to enable the VFP. - */ -static void prvEnableVFP( void ); - -/* - * Used to catch tasks that attempt to return from their implementing function. - */ -static void prvTaskExitError( void ); - -/*-----------------------------------------------------------*/ - -/* - * The number of SysTick increments that make up one tick period. - */ -#if configUSE_TICKLESS_IDLE == 1 - static uint32_t ulTimerCountsForOneTick = 0; -#endif /* configUSE_TICKLESS_IDLE */ - -/* - * The maximum number of tick periods that can be suppressed is limited by the - * 24 bit resolution of the SysTick timer. - */ -#if configUSE_TICKLESS_IDLE == 1 - static uint32_t xMaximumPossibleSuppressedTicks = 0; -#endif /* configUSE_TICKLESS_IDLE */ - -/* - * Compensate for the CPU cycles that pass while the SysTick is stopped (low - * power functionality only. - */ -#if configUSE_TICKLESS_IDLE == 1 - static uint32_t ulStoppedTimerCompensation = 0; -#endif /* configUSE_TICKLESS_IDLE */ - -/* - * Used by the portASSERT_IF_INTERRUPT_PRIORITY_INVALID() macro to ensure - * FreeRTOS API functions are not called from interrupts that have been assigned - * a priority above configMAX_SYSCALL_INTERRUPT_PRIORITY. - */ -#if ( configASSERT_DEFINED == 1 ) - static uint8_t ucMaxSysCallPriority = 0; - static uint32_t ulMaxPRIGROUPValue = 0; - static const volatile uint8_t * const pcInterruptPriorityRegisters = ( uint8_t * ) portNVIC_IP_REGISTERS_OFFSET_16; -#endif /* configASSERT_DEFINED */ - -/*-----------------------------------------------------------*/ - -/* - * See header file for description. - */ -StackType_t *pxPortInitialiseStack( StackType_t *pxTopOfStack, TaskFunction_t pxCode, void *pvParameters ) -{ - /* Simulate the stack frame as it would be created by a context switch - interrupt. */ - - /* Offset added to account for the way the MCU uses the stack on entry/exit - of interrupts, and to ensure alignment. */ - pxTopOfStack--; - - *pxTopOfStack = portINITIAL_XPSR; /* xPSR */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) pxCode; /* PC */ - pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) prvTaskExitError; /* LR */ - - /* Save code space by skipping register initialisation. */ - pxTopOfStack -= 5; /* R12, R3, R2 and R1. */ - *pxTopOfStack = ( StackType_t ) pvParameters; /* R0 */ - - /* A save method is being used that requires each task to maintain its - own exec return value. */ - pxTopOfStack--; - *pxTopOfStack = portINITIAL_EXEC_RETURN; - - pxTopOfStack -= 8; /* R11, R10, R9, R8, R7, R6, R5 and R4. */ - - return pxTopOfStack; -} -/*-----------------------------------------------------------*/ - -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( uxCriticalNesting == ~0UL ); - portDISABLE_INTERRUPTS(); - for( ;; ); -} -/*-----------------------------------------------------------*/ - -__asm void vPortSVCHandler( void ) -{ - PRESERVE8 - - /* Get the location of the current TCB. */ - ldr r3, =pxCurrentTCB - ldr r1, [r3] - ldr r0, [r1] - /* Pop the core registers. */ - ldmia r0!, {r4-r11, r14} - msr psp, r0 - isb - mov r0, #0 - msr basepri, r0 - bx r14 -} -/*-----------------------------------------------------------*/ - -__asm void prvStartFirstTask( void ) -{ - PRESERVE8 - - /* Use the NVIC offset register to locate the stack. */ - ldr r0, =0xE000ED08 - ldr r0, [r0] - ldr r0, [r0] - /* Set the msp back to the start of the stack. */ - msr msp, r0 - /* Globally enable interrupts. */ - cpsie i - dsb - isb - /* Call SVC to start the first task. */ - svc 0 - nop -} -/*-----------------------------------------------------------*/ - -__asm void prvEnableVFP( void ) -{ - PRESERVE8 - - /* The FPU enable bits are in the CPACR. */ - ldr.w r0, =0xE000ED88 - ldr r1, [r0] - - /* Enable CP10 and CP11 coprocessors, then save back. */ - orr r1, r1, #( 0xf << 20 ) - str r1, [r0] - bx r14 - nop -} -/*-----------------------------------------------------------*/ - -/* - * See header file for description. - */ -BaseType_t xPortStartScheduler( void ) -{ - #if( configASSERT_DEFINED == 1 ) - { - volatile uint32_t ulOriginalPriority; - volatile uint8_t * const pucFirstUserPriorityRegister = ( uint8_t * ) ( portNVIC_IP_REGISTERS_OFFSET_16 + portFIRST_USER_INTERRUPT_NUMBER ); - volatile uint8_t ucMaxPriorityValue; - - /* Determine the maximum priority from which ISR safe FreeRTOS API - functions can be called. ISR safe functions are those that end in - "FromISR". FreeRTOS maintains separate thread and ISR API functions to - ensure interrupt entry is as fast and simple as possible. - - Save the interrupt priority value that is about to be clobbered. */ - ulOriginalPriority = *pucFirstUserPriorityRegister; - - /* Determine the number of priority bits available. First write to all - possible bits. */ - *pucFirstUserPriorityRegister = portMAX_8_BIT_VALUE; - - /* Read the value back to see how many bits stuck. */ - ucMaxPriorityValue = *pucFirstUserPriorityRegister; - - /* Use the same mask on the maximum system call priority. */ - ucMaxSysCallPriority = configMAX_SYSCALL_INTERRUPT_PRIORITY & ucMaxPriorityValue; - - /* Calculate the maximum acceptable priority group value for the number - of bits read back. */ - ulMaxPRIGROUPValue = portMAX_PRIGROUP_BITS; - while( ( ucMaxPriorityValue & portTOP_BIT_OF_BYTE ) == portTOP_BIT_OF_BYTE ) - { - ulMaxPRIGROUPValue--; - ucMaxPriorityValue <<= ( uint8_t ) 0x01; - } - - /* Shift the priority group value back to its position within the AIRCR - register. */ - ulMaxPRIGROUPValue <<= portPRIGROUP_SHIFT; - ulMaxPRIGROUPValue &= portPRIORITY_GROUP_MASK; - - /* Restore the clobbered interrupt priority register to its original - value. */ - *pucFirstUserPriorityRegister = ulOriginalPriority; - } - #endif /* conifgASSERT_DEFINED */ - - /* Make PendSV and SysTick the lowest priority interrupts. */ - portNVIC_SYSPRI2_REG |= portNVIC_PENDSV_PRI; - portNVIC_SYSPRI2_REG |= portNVIC_SYSTICK_PRI; - - /* Start the timer that generates the tick ISR. Interrupts are disabled - here already. */ - vPortSetupTimerInterrupt(); - - /* Initialise the critical nesting count ready for the first task. */ - uxCriticalNesting = 0; - - /* Ensure the VFP is enabled - it should be anyway. */ - prvEnableVFP(); - - /* Lazy save always. */ - *( portFPCCR ) |= portASPEN_AND_LSPEN_BITS; - - /* Start the first task. */ - prvStartFirstTask(); - - /* Should not get here! */ - return 0; -} -/*-----------------------------------------------------------*/ - -void vPortEndScheduler( void ) -{ - /* Not implemented in ports where there is nothing to return to. - Artificially force an assert. */ - configASSERT( uxCriticalNesting == 1000UL ); -} -/*-----------------------------------------------------------*/ - -void vPortYield( void ) -{ - /* Set a PendSV to request a context switch. */ - portNVIC_INT_CTRL_REG = portNVIC_PENDSVSET_BIT; - - /* Barriers are normally not required but do ensure the code is completely - within the specified behaviour for the architecture. */ - __dsb( portSY_FULL_READ_WRITE ); - __isb( portSY_FULL_READ_WRITE ); -} -/*-----------------------------------------------------------*/ - -void vPortEnterCritical( void ) -{ - portDISABLE_INTERRUPTS(); - uxCriticalNesting++; - __dsb( portSY_FULL_READ_WRITE ); - __isb( portSY_FULL_READ_WRITE ); -} -/*-----------------------------------------------------------*/ - -void vPortExitCritical( void ) -{ - configASSERT( uxCriticalNesting ); - uxCriticalNesting--; - if( uxCriticalNesting == 0 ) - { - portENABLE_INTERRUPTS(); - } -} -/*-----------------------------------------------------------*/ - -__asm void xPortPendSVHandler( void ) -{ - extern uxCriticalNesting; - extern pxCurrentTCB; - extern vTaskSwitchContext; - - PRESERVE8 - - mrs r0, psp - isb - /* Get the location of the current TCB. */ - ldr r3, =pxCurrentTCB - ldr r2, [r3] - - /* Is the task using the FPU context? If so, push high vfp registers. */ - tst r14, #0x10 - it eq - vstmdbeq r0!, {s16-s31} - - /* Save the core registers. */ - stmdb r0!, {r4-r11, r14} - - /* Save the new top of stack into the first member of the TCB. */ - str r0, [r2] - - stmdb sp!, {r3} - mov r0, #configMAX_SYSCALL_INTERRUPT_PRIORITY - msr basepri, r0 - bl vTaskSwitchContext - mov r0, #0 - msr basepri, r0 - ldmia sp!, {r3} - - /* The first item in pxCurrentTCB is the task top of stack. */ - ldr r1, [r3] - ldr r0, [r1] - - /* Pop the core registers. */ - ldmia r0!, {r4-r11, r14} - - /* Is the task using the FPU context? If so, pop the high vfp registers - too. */ - tst r14, #0x10 - it eq - vldmiaeq r0!, {s16-s31} - - msr psp, r0 - isb - #ifdef WORKAROUND_PMU_CM001 /* XMC4000 specific errata */ - #if WORKAROUND_PMU_CM001 == 1 - push { r14 } - pop { pc } - nop - #endif - #endif - - bx r14 - nop - nop -} -/*-----------------------------------------------------------*/ - -void xPortSysTickHandler( void ) -{ - /* The SysTick runs at the lowest interrupt priority, so when this interrupt - executes all interrupts must be unmasked. There is therefore no need to - save and then restore the interrupt mask value as its value is already - known. */ - ( void ) portSET_INTERRUPT_MASK_FROM_ISR(); - { - /* Increment the RTOS tick. */ - if( xTaskIncrementTick() != pdFALSE ) - { - /* A context switch is required. Context switching is performed in - the PendSV interrupt. Pend the PendSV interrupt. */ - portNVIC_INT_CTRL_REG = portNVIC_PENDSVSET_BIT; - } - } - portCLEAR_INTERRUPT_MASK_FROM_ISR( 0 ); -} -/*-----------------------------------------------------------*/ - -#if configUSE_TICKLESS_IDLE == 1 - - __weak void vPortSuppressTicksAndSleep( TickType_t xExpectedIdleTime ) - { - uint32_t ulReloadValue, ulCompleteTickPeriods, ulCompletedSysTickDecrements, ulSysTickCTRL; - TickType_t xModifiableIdleTime; - - /* Make sure the SysTick reload value does not overflow the counter. */ - if( xExpectedIdleTime > xMaximumPossibleSuppressedTicks ) - { - xExpectedIdleTime = xMaximumPossibleSuppressedTicks; - } - - /* Stop the SysTick momentarily. The time the SysTick is stopped for - is accounted for as best it can be, but using the tickless mode will - inevitably result in some tiny drift of the time maintained by the - kernel with respect to calendar time. */ - portNVIC_SYSTICK_CTRL_REG &= ~portNVIC_SYSTICK_ENABLE_BIT; - - /* Calculate the reload value required to wait xExpectedIdleTime - tick periods. -1 is used because this code will execute part way - through one of the tick periods. */ - ulReloadValue = portNVIC_SYSTICK_CURRENT_VALUE_REG + ( ulTimerCountsForOneTick * ( xExpectedIdleTime - 1UL ) ); - if( ulReloadValue > ulStoppedTimerCompensation ) - { - ulReloadValue -= ulStoppedTimerCompensation; - } - - /* Enter a critical section but don't use the taskENTER_CRITICAL() - method as that will mask interrupts that should exit sleep mode. */ - __disable_irq(); - - /* If a context switch is pending or a task is waiting for the scheduler - to be unsuspended then abandon the low power entry. */ - if( eTaskConfirmSleepModeStatus() == eAbortSleep ) - { - /* Restart from whatever is left in the count register to complete - this tick period. */ - portNVIC_SYSTICK_LOAD_REG = portNVIC_SYSTICK_CURRENT_VALUE_REG; - - /* Restart SysTick. */ - portNVIC_SYSTICK_CTRL_REG |= portNVIC_SYSTICK_ENABLE_BIT; - - /* Reset the reload register to the value required for normal tick - periods. */ - portNVIC_SYSTICK_LOAD_REG = ulTimerCountsForOneTick - 1UL; - - /* Re-enable interrupts - see comments above __disable_irq() call - above. */ - __enable_irq(); - } - else - { - /* Set the new reload value. */ - portNVIC_SYSTICK_LOAD_REG = ulReloadValue; - - /* Clear the SysTick count flag and set the count value back to - zero. */ - portNVIC_SYSTICK_CURRENT_VALUE_REG = 0UL; - - /* Restart SysTick. */ - portNVIC_SYSTICK_CTRL_REG |= portNVIC_SYSTICK_ENABLE_BIT; - - /* Sleep until something happens. configPRE_SLEEP_PROCESSING() can - set its parameter to 0 to indicate that its implementation contains - its own wait for interrupt or wait for event instruction, and so wfi - should not be executed again. However, the original expected idle - time variable must remain unmodified, so a copy is taken. */ - xModifiableIdleTime = xExpectedIdleTime; - configPRE_SLEEP_PROCESSING( xModifiableIdleTime ); - if( xModifiableIdleTime > 0 ) - { - __dsb( portSY_FULL_READ_WRITE ); - __wfi(); - __isb( portSY_FULL_READ_WRITE ); - } - configPOST_SLEEP_PROCESSING( xExpectedIdleTime ); - - /* Stop SysTick. Again, the time the SysTick is stopped for is - accounted for as best it can be, but using the tickless mode will - inevitably result in some tiny drift of the time maintained by the - kernel with respect to calendar time. */ - ulSysTickCTRL = portNVIC_SYSTICK_CTRL_REG; - portNVIC_SYSTICK_CTRL_REG = ( ulSysTickCTRL & ~portNVIC_SYSTICK_ENABLE_BIT ); - - /* Re-enable interrupts - see comments above __disable_irq() call - above. */ - __enable_irq(); - - if( ( ulSysTickCTRL & portNVIC_SYSTICK_COUNT_FLAG_BIT ) != 0 ) - { - uint32_t ulCalculatedLoadValue; - - /* The tick interrupt has already executed, and the SysTick - count reloaded with ulReloadValue. Reset the - portNVIC_SYSTICK_LOAD_REG with whatever remains of this tick - period. */ - ulCalculatedLoadValue = ( ulTimerCountsForOneTick - 1UL ) - ( ulReloadValue - portNVIC_SYSTICK_CURRENT_VALUE_REG ); - - /* Don't allow a tiny value, or values that have somehow - underflowed because the post sleep hook did something - that took too long. */ - if( ( ulCalculatedLoadValue < ulStoppedTimerCompensation ) || ( ulCalculatedLoadValue > ulTimerCountsForOneTick ) ) - { - ulCalculatedLoadValue = ( ulTimerCountsForOneTick - 1UL ); - } - - portNVIC_SYSTICK_LOAD_REG = ulCalculatedLoadValue; - - /* The tick interrupt handler will already have pended the tick - processing in the kernel. As the pending tick will be - processed as soon as this function exits, the tick value - maintained by the tick is stepped forward by one less than the - time spent waiting. */ - ulCompleteTickPeriods = xExpectedIdleTime - 1UL; - } - else - { - /* Something other than the tick interrupt ended the sleep. - Work out how long the sleep lasted rounded to complete tick - periods (not the ulReload value which accounted for part - ticks). */ - ulCompletedSysTickDecrements = ( xExpectedIdleTime * ulTimerCountsForOneTick ) - portNVIC_SYSTICK_CURRENT_VALUE_REG; - - /* How many complete tick periods passed while the processor - was waiting? */ - ulCompleteTickPeriods = ulCompletedSysTickDecrements / ulTimerCountsForOneTick; - - /* The reload value is set to whatever fraction of a single tick - period remains. */ - portNVIC_SYSTICK_LOAD_REG = ( ( ulCompleteTickPeriods + 1 ) * ulTimerCountsForOneTick ) - ulCompletedSysTickDecrements; - } - - /* Restart SysTick so it runs from portNVIC_SYSTICK_LOAD_REG - again, then set portNVIC_SYSTICK_LOAD_REG back to its standard - value. The critical section is used to ensure the tick interrupt - can only execute once in the case that the reload register is near - zero. */ - portNVIC_SYSTICK_CURRENT_VALUE_REG = 0UL; - portENTER_CRITICAL(); - { - portNVIC_SYSTICK_CTRL_REG |= portNVIC_SYSTICK_ENABLE_BIT; - vTaskStepTick( ulCompleteTickPeriods ); - portNVIC_SYSTICK_LOAD_REG = ulTimerCountsForOneTick - 1UL; - } - portEXIT_CRITICAL(); - } - } - -#endif /* #if configUSE_TICKLESS_IDLE */ - -/*-----------------------------------------------------------*/ - -/* - * Setup the SysTick timer to generate the tick interrupts at the required - * frequency. - */ -#if configOVERRIDE_DEFAULT_TICK_CONFIGURATION == 0 - - void vPortSetupTimerInterrupt( void ) - { - /* Calculate the constants required to configure the tick interrupt. */ - #if configUSE_TICKLESS_IDLE == 1 - { - ulTimerCountsForOneTick = ( configSYSTICK_CLOCK_HZ / configTICK_RATE_HZ ); - xMaximumPossibleSuppressedTicks = portMAX_24_BIT_NUMBER / ulTimerCountsForOneTick; - ulStoppedTimerCompensation = portMISSED_COUNTS_FACTOR / ( configCPU_CLOCK_HZ / configSYSTICK_CLOCK_HZ ); - } - #endif /* configUSE_TICKLESS_IDLE */ - - /* Configure SysTick to interrupt at the requested rate. */ - portNVIC_SYSTICK_LOAD_REG = ( configSYSTICK_CLOCK_HZ / configTICK_RATE_HZ ) - 1UL; - portNVIC_SYSTICK_CTRL_REG = ( portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT | portNVIC_SYSTICK_ENABLE_BIT ); - } - -#endif /* configOVERRIDE_DEFAULT_TICK_CONFIGURATION */ -/*-----------------------------------------------------------*/ - -__asm uint32_t ulPortSetInterruptMask( void ) -{ - PRESERVE8 - - mrs r0, basepri - mov r1, #configMAX_SYSCALL_INTERRUPT_PRIORITY - msr basepri, r1 - bx r14 -} -/*-----------------------------------------------------------*/ - -__asm void vPortClearInterruptMask( uint32_t ulNewMask ) -{ - PRESERVE8 - - msr basepri, r0 - bx r14 -} -/*-----------------------------------------------------------*/ - -__asm uint32_t vPortGetIPSR( void ) -{ - PRESERVE8 - - mrs r0, ipsr - bx r14 -} -/*-----------------------------------------------------------*/ - -#if( configASSERT_DEFINED == 1 ) - - void vPortValidateInterruptPriority( void ) - { - uint32_t ulCurrentInterrupt; - uint8_t ucCurrentPriority; - - /* Obtain the number of the currently executing interrupt. */ - ulCurrentInterrupt = vPortGetIPSR(); - - /* Is the interrupt number a user defined interrupt? */ - if( ulCurrentInterrupt >= portFIRST_USER_INTERRUPT_NUMBER ) - { - /* Look up the interrupt's priority. */ - ucCurrentPriority = pcInterruptPriorityRegisters[ ulCurrentInterrupt ]; - - /* The following assertion will fail if a service routine (ISR) for - an interrupt that has been assigned a priority above - configMAX_SYSCALL_INTERRUPT_PRIORITY calls an ISR safe FreeRTOS API - function. ISR safe FreeRTOS API functions must *only* be called - from interrupts that have been assigned a priority at or below - configMAX_SYSCALL_INTERRUPT_PRIORITY. - - Numerically low interrupt priority numbers represent logically high - interrupt priorities, therefore the priority of the interrupt must - be set to a value equal to or numerically *higher* than - configMAX_SYSCALL_INTERRUPT_PRIORITY. - - Interrupts that use the FreeRTOS API must not be left at their - default priority of zero as that is the highest possible priority, - which is guaranteed to be above configMAX_SYSCALL_INTERRUPT_PRIORITY, - and therefore also guaranteed to be invalid. - - FreeRTOS maintains separate thread and ISR API functions to ensure - interrupt entry is as fast and simple as possible. - - The following links provide detailed information: - http://www.freertos.org/RTOS-Cortex-M3-M4.html - http://www.freertos.org/FAQHelp.html */ - configASSERT( ucCurrentPriority >= ucMaxSysCallPriority ); - } - - /* Priority grouping: The interrupt controller (NVIC) allows the bits - that define each interrupt's priority to be split between bits that - define the interrupt's pre-emption priority bits and bits that define - the interrupt's sub-priority. For simplicity all bits must be defined - to be pre-emption priority bits. The following assertion will fail if - this is not the case (if some bits represent a sub-priority). - - If the application only uses CMSIS libraries for interrupt - configuration then the correct setting can be achieved on all Cortex-M - devices by calling NVIC_SetPriorityGrouping( 0 ); before starting the - scheduler. Note however that some vendor specific peripheral libraries - assume a non-zero priority group setting, in which cases using a value - of zero will result in unpredicable behaviour. */ - configASSERT( ( portAIRCR_REG & portPRIORITY_GROUP_MASK ) <= ulMaxPRIGROUPValue ); - } - -#endif /* configASSERT_DEFINED */ - - +/*
+ FreeRTOS V8.2.3 - Copyright (C) 2015 Real Time Engineers Ltd.
+ All rights reserved
+
+ VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
+
+ This file is part of the FreeRTOS distribution.
+
+ FreeRTOS is free software; you can redistribute it and/or modify it under
+ the terms of the GNU General Public License (version 2) as published by the
+ Free Software Foundation >>>> AND MODIFIED BY <<<< the FreeRTOS exception.
+
+ ***************************************************************************
+ >>! NOTE: The modification to the GPL is included to allow you to !<<
+ >>! distribute a combined work that includes FreeRTOS without being !<<
+ >>! obliged to provide the source code for proprietary components !<<
+ >>! outside of the FreeRTOS kernel. !<<
+ ***************************************************************************
+
+ FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY
+ WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+ FOR A PARTICULAR PURPOSE. Full license text is available on the following
+ link: http://www.freertos.org/a00114.html
+
+ ***************************************************************************
+ * *
+ * FreeRTOS provides completely free yet professionally developed, *
+ * robust, strictly quality controlled, supported, and cross *
+ * platform software that is more than just the market leader, it *
+ * is the industry's de facto standard. *
+ * *
+ * Help yourself get started quickly while simultaneously helping *
+ * to support the FreeRTOS project by purchasing a FreeRTOS *
+ * tutorial book, reference manual, or both: *
+ * http://www.FreeRTOS.org/Documentation *
+ * *
+ ***************************************************************************
+
+ http://www.FreeRTOS.org/FAQHelp.html - Having a problem? Start by reading
+ the FAQ page "My application does not run, what could be wrong?". Have you
+ defined configASSERT()?
+
+ http://www.FreeRTOS.org/support - In return for receiving this top quality
+ embedded software for free we request you assist our global community by
+ participating in the support forum.
+
+ http://www.FreeRTOS.org/training - Investing in training allows your team to
+ be as productive as possible as early as possible. Now you can receive
+ FreeRTOS training directly from Richard Barry, CEO of Real Time Engineers
+ Ltd, and the world's leading authority on the world's leading RTOS.
+
+ http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
+ including FreeRTOS+Trace - an indispensable productivity tool, a DOS
+ compatible FAT file system, and our tiny thread aware UDP/IP stack.
+
+ http://www.FreeRTOS.org/labs - Where new FreeRTOS products go to incubate.
+ Come and try FreeRTOS+TCP, our new open source TCP/IP stack for FreeRTOS.
+
+ http://www.OpenRTOS.com - Real Time Engineers ltd. license FreeRTOS to High
+ Integrity Systems ltd. to sell under the OpenRTOS brand. Low cost OpenRTOS
+ licenses offer ticketed support, indemnification and commercial middleware.
+
+ http://www.SafeRTOS.com - High Integrity Systems also provide a safety
+ engineered and independently SIL3 certified version for use in safety and
+ mission critical applications that require provable dependability.
+
+ 1 tab == 4 spaces!
+*/
+
+/*-----------------------------------------------------------
+ * Implementation of functions defined in portable.h for the ARM CM4F port.
+ *----------------------------------------------------------*/
+
+/* Scheduler includes. */
+#include "FreeRTOS.h"
+#include "task.h"
+
+#ifndef __TARGET_FPU_VFP
+ #error This port can only be used when the project options are configured to enable hardware floating point support.
+#endif
+
+#if configMAX_SYSCALL_INTERRUPT_PRIORITY == 0
+ #error configMAX_SYSCALL_INTERRUPT_PRIORITY must not be set to 0. See http://www.FreeRTOS.org/RTOS-Cortex-M3-M4.html
+#endif
+
+#ifndef configSYSTICK_CLOCK_HZ
+ #define configSYSTICK_CLOCK_HZ configCPU_CLOCK_HZ
+ /* Ensure the SysTick is clocked at the same frequency as the core. */
+ #define portNVIC_SYSTICK_CLK_BIT ( 1UL << 2UL )
+#else
+ /* The way the SysTick is clocked is not modified in case it is not the same
+ as the core. */
+ #define portNVIC_SYSTICK_CLK_BIT ( 0 )
+#endif
+
+/* The __weak attribute does not work as you might expect with the Keil tools
+so the configOVERRIDE_DEFAULT_TICK_CONFIGURATION constant must be set to 1 if
+the application writer wants to provide their own implementation of
+vPortSetupTimerInterrupt(). Ensure configOVERRIDE_DEFAULT_TICK_CONFIGURATION
+is defined. */
+#ifndef configOVERRIDE_DEFAULT_TICK_CONFIGURATION
+ #define configOVERRIDE_DEFAULT_TICK_CONFIGURATION 0
+#endif
+
+/* Constants required to manipulate the core. Registers first... */
+#define portNVIC_SYSTICK_CTRL_REG ( * ( ( volatile uint32_t * ) 0xe000e010 ) )
+#define portNVIC_SYSTICK_LOAD_REG ( * ( ( volatile uint32_t * ) 0xe000e014 ) )
+#define portNVIC_SYSTICK_CURRENT_VALUE_REG ( * ( ( volatile uint32_t * ) 0xe000e018 ) )
+#define portNVIC_SYSPRI2_REG ( * ( ( volatile uint32_t * ) 0xe000ed20 ) )
+/* ...then bits in the registers. */
+#define portNVIC_SYSTICK_INT_BIT ( 1UL << 1UL )
+#define portNVIC_SYSTICK_ENABLE_BIT ( 1UL << 0UL )
+#define portNVIC_SYSTICK_COUNT_FLAG_BIT ( 1UL << 16UL )
+#define portNVIC_PENDSVCLEAR_BIT ( 1UL << 27UL )
+#define portNVIC_PEND_SYSTICK_CLEAR_BIT ( 1UL << 25UL )
+
+/* Constants used to detect a Cortex-M7 r0p1 core, which should use the ARM_CM7
+r0p1 port. */
+#define portCPUID ( * ( ( volatile uint32_t * ) 0xE000ed00 ) )
+#define portCORTEX_M7_r0p1_ID ( 0x410FC271UL )
+#define portCORTEX_M7_r0p0_ID ( 0x410FC270UL )
+
+#define portNVIC_PENDSV_PRI ( ( ( uint32_t ) configKERNEL_INTERRUPT_PRIORITY ) << 16UL )
+#define portNVIC_SYSTICK_PRI ( ( ( uint32_t ) configKERNEL_INTERRUPT_PRIORITY ) << 24UL )
+
+/* Constants required to check the validity of an interrupt priority. */
+#define portFIRST_USER_INTERRUPT_NUMBER ( 16 )
+#define portNVIC_IP_REGISTERS_OFFSET_16 ( 0xE000E3F0 )
+#define portAIRCR_REG ( * ( ( volatile uint32_t * ) 0xE000ED0C ) )
+#define portMAX_8_BIT_VALUE ( ( uint8_t ) 0xff )
+#define portTOP_BIT_OF_BYTE ( ( uint8_t ) 0x80 )
+#define portMAX_PRIGROUP_BITS ( ( uint8_t ) 7 )
+#define portPRIORITY_GROUP_MASK ( 0x07UL << 8UL )
+#define portPRIGROUP_SHIFT ( 8UL )
+
+/* Masks off all bits but the VECTACTIVE bits in the ICSR register. */
+#define portVECTACTIVE_MASK ( 0xFFUL )
+
+/* Constants required to manipulate the VFP. */
+#define portFPCCR ( ( volatile uint32_t * ) 0xe000ef34 ) /* Floating point context control register. */
+#define portASPEN_AND_LSPEN_BITS ( 0x3UL << 30UL )
+
+/* Constants required to set up the initial stack. */
+#define portINITIAL_XPSR ( 0x01000000 )
+#define portINITIAL_EXEC_RETURN ( 0xfffffffd )
+
+/* The systick is a 24-bit counter. */
+#define portMAX_24_BIT_NUMBER ( 0xffffffUL )
+
+/* A fiddle factor to estimate the number of SysTick counts that would have
+occurred while the SysTick counter is stopped during tickless idle
+calculations. */
+#define portMISSED_COUNTS_FACTOR ( 45UL )
+
+/* Each task maintains its own interrupt status in the critical nesting
+variable. */
+static UBaseType_t uxCriticalNesting = 0xaaaaaaaa;
+
+/*
+ * Setup the timer to generate the tick interrupts. The implementation in this
+ * file is weak to allow application writers to change the timer used to
+ * generate the tick interrupt.
+ */
+void vPortSetupTimerInterrupt( void );
+
+/*
+ * Exception handlers.
+ */
+void xPortPendSVHandler( void );
+void xPortSysTickHandler( void );
+void vPortSVCHandler( void );
+
+/*
+ * Start first task is a separate function so it can be tested in isolation.
+ */
+static void prvStartFirstTask( void );
+
+/*
+ * Functions defined in portasm.s to enable the VFP.
+ */
+static void prvEnableVFP( void );
+
+/*
+ * Used to catch tasks that attempt to return from their implementing function.
+ */
+static void prvTaskExitError( void );
+
+/*-----------------------------------------------------------*/
+
+/*
+ * The number of SysTick increments that make up one tick period.
+ */
+#if configUSE_TICKLESS_IDLE == 1
+ static uint32_t ulTimerCountsForOneTick = 0;
+#endif /* configUSE_TICKLESS_IDLE */
+
+/*
+ * The maximum number of tick periods that can be suppressed is limited by the
+ * 24 bit resolution of the SysTick timer.
+ */
+#if configUSE_TICKLESS_IDLE == 1
+ static uint32_t xMaximumPossibleSuppressedTicks = 0;
+#endif /* configUSE_TICKLESS_IDLE */
+
+/*
+ * Compensate for the CPU cycles that pass while the SysTick is stopped (low
+ * power functionality only.
+ */
+#if configUSE_TICKLESS_IDLE == 1
+ static uint32_t ulStoppedTimerCompensation = 0;
+#endif /* configUSE_TICKLESS_IDLE */
+
+/*
+ * Used by the portASSERT_IF_INTERRUPT_PRIORITY_INVALID() macro to ensure
+ * FreeRTOS API functions are not called from interrupts that have been assigned
+ * a priority above configMAX_SYSCALL_INTERRUPT_PRIORITY.
+ */
+#if ( configASSERT_DEFINED == 1 )
+ static uint8_t ucMaxSysCallPriority = 0;
+ static uint32_t ulMaxPRIGROUPValue = 0;
+ static const volatile uint8_t * const pcInterruptPriorityRegisters = ( uint8_t * ) portNVIC_IP_REGISTERS_OFFSET_16;
+#endif /* configASSERT_DEFINED */
+
+/*-----------------------------------------------------------*/
+
+/*
+ * See header file for description.
+ */
+StackType_t *pxPortInitialiseStack( StackType_t *pxTopOfStack, TaskFunction_t pxCode, void *pvParameters )
+{
+ /* Simulate the stack frame as it would be created by a context switch
+ interrupt. */
+
+ /* Offset added to account for the way the MCU uses the stack on entry/exit
+ of interrupts, and to ensure alignment. */
+ pxTopOfStack--;
+
+ *pxTopOfStack = portINITIAL_XPSR; /* xPSR */
+ pxTopOfStack--;
+ *pxTopOfStack = ( StackType_t ) pxCode; /* PC */
+ pxTopOfStack--;
+ *pxTopOfStack = ( StackType_t ) prvTaskExitError; /* LR */
+
+ /* Save code space by skipping register initialisation. */
+ pxTopOfStack -= 5; /* R12, R3, R2 and R1. */
+ *pxTopOfStack = ( StackType_t ) pvParameters; /* R0 */
+
+ /* A save method is being used that requires each task to maintain its
+ own exec return value. */
+ pxTopOfStack--;
+ *pxTopOfStack = portINITIAL_EXEC_RETURN;
+
+ pxTopOfStack -= 8; /* R11, R10, R9, R8, R7, R6, R5 and R4. */
+
+ return pxTopOfStack;
+}
+/*-----------------------------------------------------------*/
+
+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( uxCriticalNesting == ~0UL );
+ portDISABLE_INTERRUPTS();
+ for( ;; );
+}
+/*-----------------------------------------------------------*/
+
+__asm void vPortSVCHandler( void )
+{
+ PRESERVE8
+
+ /* Get the location of the current TCB. */
+ ldr r3, =pxCurrentTCB
+ ldr r1, [r3]
+ ldr r0, [r1]
+ /* Pop the core registers. */
+ ldmia r0!, {r4-r11, r14}
+ msr psp, r0
+ isb
+ mov r0, #0
+ msr basepri, r0
+ bx r14
+}
+/*-----------------------------------------------------------*/
+
+__asm void prvStartFirstTask( void )
+{
+ PRESERVE8
+
+ /* Use the NVIC offset register to locate the stack. */
+ ldr r0, =0xE000ED08
+ ldr r0, [r0]
+ ldr r0, [r0]
+ /* Set the msp back to the start of the stack. */
+ msr msp, r0
+ /* Globally enable interrupts. */
+ cpsie i
+ cpsie f
+ dsb
+ isb
+ /* Call SVC to start the first task. */
+ svc 0
+ nop
+ nop
+}
+/*-----------------------------------------------------------*/
+
+__asm void prvEnableVFP( void )
+{
+ PRESERVE8
+
+ /* The FPU enable bits are in the CPACR. */
+ ldr.w r0, =0xE000ED88
+ ldr r1, [r0]
+
+ /* Enable CP10 and CP11 coprocessors, then save back. */
+ orr r1, r1, #( 0xf << 20 )
+ str r1, [r0]
+ bx r14
+ nop
+}
+/*-----------------------------------------------------------*/
+
+/*
+ * See header file for description.
+ */
+BaseType_t xPortStartScheduler( void )
+{
+ /* configMAX_SYSCALL_INTERRUPT_PRIORITY must not be set to 0.
+ See http://www.FreeRTOS.org/RTOS-Cortex-M3-M4.html */
+ configASSERT( configMAX_SYSCALL_INTERRUPT_PRIORITY );
+
+ /* This port can be used on all revisions of the Cortex-M7 core other than
+ the r0p1 parts. r0p1 parts should use the port from the
+ /source/portable/GCC/ARM_CM7/r0p1 directory. */
+ configASSERT( portCPUID != portCORTEX_M7_r0p1_ID );
+ configASSERT( portCPUID != portCORTEX_M7_r0p0_ID );
+
+ #if( configASSERT_DEFINED == 1 )
+ {
+ volatile uint32_t ulOriginalPriority;
+ volatile uint8_t * const pucFirstUserPriorityRegister = ( uint8_t * ) ( portNVIC_IP_REGISTERS_OFFSET_16 + portFIRST_USER_INTERRUPT_NUMBER );
+ volatile uint8_t ucMaxPriorityValue;
+
+ /* Determine the maximum priority from which ISR safe FreeRTOS API
+ functions can be called. ISR safe functions are those that end in
+ "FromISR". FreeRTOS maintains separate thread and ISR API functions to
+ ensure interrupt entry is as fast and simple as possible.
+
+ Save the interrupt priority value that is about to be clobbered. */
+ ulOriginalPriority = *pucFirstUserPriorityRegister;
+
+ /* Determine the number of priority bits available. First write to all
+ possible bits. */
+ *pucFirstUserPriorityRegister = portMAX_8_BIT_VALUE;
+
+ /* Read the value back to see how many bits stuck. */
+ ucMaxPriorityValue = *pucFirstUserPriorityRegister;
+
+ /* The kernel interrupt priority should be set to the lowest
+ priority. */
+ configASSERT( ucMaxPriorityValue == ( configKERNEL_INTERRUPT_PRIORITY & ucMaxPriorityValue ) );
+
+ /* Use the same mask on the maximum system call priority. */
+ ucMaxSysCallPriority = configMAX_SYSCALL_INTERRUPT_PRIORITY & ucMaxPriorityValue;
+
+ /* Calculate the maximum acceptable priority group value for the number
+ of bits read back. */
+ ulMaxPRIGROUPValue = portMAX_PRIGROUP_BITS;
+ while( ( ucMaxPriorityValue & portTOP_BIT_OF_BYTE ) == portTOP_BIT_OF_BYTE )
+ {
+ ulMaxPRIGROUPValue--;
+ ucMaxPriorityValue <<= ( uint8_t ) 0x01;
+ }
+
+ /* Shift the priority group value back to its position within the AIRCR
+ register. */
+ ulMaxPRIGROUPValue <<= portPRIGROUP_SHIFT;
+ ulMaxPRIGROUPValue &= portPRIORITY_GROUP_MASK;
+
+ /* Restore the clobbered interrupt priority register to its original
+ value. */
+ *pucFirstUserPriorityRegister = ulOriginalPriority;
+ }
+ #endif /* conifgASSERT_DEFINED */
+
+ /* Make PendSV and SysTick the lowest priority interrupts. */
+ portNVIC_SYSPRI2_REG |= portNVIC_PENDSV_PRI;
+ portNVIC_SYSPRI2_REG |= portNVIC_SYSTICK_PRI;
+
+ /* Start the timer that generates the tick ISR. Interrupts are disabled
+ here already. */
+ vPortSetupTimerInterrupt();
+
+ /* Initialise the critical nesting count ready for the first task. */
+ uxCriticalNesting = 0;
+
+ /* Ensure the VFP is enabled - it should be anyway. */
+ prvEnableVFP();
+
+ /* Lazy save always. */
+ *( portFPCCR ) |= portASPEN_AND_LSPEN_BITS;
+
+ /* Start the first task. */
+ prvStartFirstTask();
+
+ /* Should not get here! */
+ return 0;
+}
+/*-----------------------------------------------------------*/
+
+void vPortEndScheduler( void )
+{
+ /* Not implemented in ports where there is nothing to return to.
+ Artificially force an assert. */
+ configASSERT( uxCriticalNesting == 1000UL );
+}
+/*-----------------------------------------------------------*/
+
+void vPortEnterCritical( void )
+{
+ portDISABLE_INTERRUPTS();
+ uxCriticalNesting++;
+
+ /* 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( uxCriticalNesting == 1 )
+ {
+ configASSERT( ( portNVIC_INT_CTRL_REG & portVECTACTIVE_MASK ) == 0 );
+ }
+}
+/*-----------------------------------------------------------*/
+
+void vPortExitCritical( void )
+{
+ configASSERT( uxCriticalNesting );
+ uxCriticalNesting--;
+ if( uxCriticalNesting == 0 )
+ {
+ portENABLE_INTERRUPTS();
+ }
+}
+/*-----------------------------------------------------------*/
+
+__asm void xPortPendSVHandler( void )
+{
+ extern uxCriticalNesting;
+ extern pxCurrentTCB;
+ extern vTaskSwitchContext;
+
+ PRESERVE8
+
+ mrs r0, psp
+ isb
+ /* Get the location of the current TCB. */
+ ldr r3, =pxCurrentTCB
+ ldr r2, [r3]
+
+ /* Is the task using the FPU context? If so, push high vfp registers. */
+ tst r14, #0x10
+ it eq
+ vstmdbeq r0!, {s16-s31}
+
+ /* Save the core registers. */
+ stmdb r0!, {r4-r11, r14}
+
+ /* Save the new top of stack into the first member of the TCB. */
+ str r0, [r2]
+
+ stmdb sp!, {r3}
+ mov r0, #configMAX_SYSCALL_INTERRUPT_PRIORITY
+ msr basepri, r0
+ dsb
+ isb
+ bl vTaskSwitchContext
+ mov r0, #0
+ msr basepri, r0
+ ldmia sp!, {r3}
+
+ /* The first item in pxCurrentTCB is the task top of stack. */
+ ldr r1, [r3]
+ ldr r0, [r1]
+
+ /* Pop the core registers. */
+ ldmia r0!, {r4-r11, r14}
+
+ /* Is the task using the FPU context? If so, pop the high vfp registers
+ too. */
+ tst r14, #0x10
+ it eq
+ vldmiaeq r0!, {s16-s31}
+
+ msr psp, r0
+ isb
+ #ifdef WORKAROUND_PMU_CM001 /* XMC4000 specific errata */
+ #if WORKAROUND_PMU_CM001 == 1
+ push { r14 }
+ pop { pc }
+ nop
+ #endif
+ #endif
+
+ bx r14
+}
+/*-----------------------------------------------------------*/
+
+void xPortSysTickHandler( void )
+{
+ /* The SysTick runs at the lowest interrupt priority, so when this interrupt
+ executes all interrupts must be unmasked. There is therefore no need to
+ save and then restore the interrupt mask value as its value is already
+ known. */
+ ( void ) portSET_INTERRUPT_MASK_FROM_ISR();
+ {
+ /* Increment the RTOS tick. */
+ if( xTaskIncrementTick() != pdFALSE )
+ {
+ /* A context switch is required. Context switching is performed in
+ the PendSV interrupt. Pend the PendSV interrupt. */
+ portNVIC_INT_CTRL_REG = portNVIC_PENDSVSET_BIT;
+ }
+ }
+ portCLEAR_INTERRUPT_MASK_FROM_ISR( 0 );
+}
+/*-----------------------------------------------------------*/
+
+#if configUSE_TICKLESS_IDLE == 1
+
+ __weak void vPortSuppressTicksAndSleep( TickType_t xExpectedIdleTime )
+ {
+ uint32_t ulReloadValue, ulCompleteTickPeriods, ulCompletedSysTickDecrements, ulSysTickCTRL;
+ TickType_t xModifiableIdleTime;
+
+ /* Make sure the SysTick reload value does not overflow the counter. */
+ if( xExpectedIdleTime > xMaximumPossibleSuppressedTicks )
+ {
+ xExpectedIdleTime = xMaximumPossibleSuppressedTicks;
+ }
+
+ /* Stop the SysTick momentarily. The time the SysTick is stopped for
+ is accounted for as best it can be, but using the tickless mode will
+ inevitably result in some tiny drift of the time maintained by the
+ kernel with respect to calendar time. */
+ portNVIC_SYSTICK_CTRL_REG &= ~portNVIC_SYSTICK_ENABLE_BIT;
+
+ /* Calculate the reload value required to wait xExpectedIdleTime
+ tick periods. -1 is used because this code will execute part way
+ through one of the tick periods. */
+ ulReloadValue = portNVIC_SYSTICK_CURRENT_VALUE_REG + ( ulTimerCountsForOneTick * ( xExpectedIdleTime - 1UL ) );
+ if( ulReloadValue > ulStoppedTimerCompensation )
+ {
+ ulReloadValue -= ulStoppedTimerCompensation;
+ }
+
+ /* Enter a critical section but don't use the taskENTER_CRITICAL()
+ method as that will mask interrupts that should exit sleep mode. */
+ __disable_irq();
+
+ /* If a context switch is pending or a task is waiting for the scheduler
+ to be unsuspended then abandon the low power entry. */
+ if( eTaskConfirmSleepModeStatus() == eAbortSleep )
+ {
+ /* Restart from whatever is left in the count register to complete
+ this tick period. */
+ portNVIC_SYSTICK_LOAD_REG = portNVIC_SYSTICK_CURRENT_VALUE_REG;
+
+ /* Restart SysTick. */
+ portNVIC_SYSTICK_CTRL_REG |= portNVIC_SYSTICK_ENABLE_BIT;
+
+ /* Reset the reload register to the value required for normal tick
+ periods. */
+ portNVIC_SYSTICK_LOAD_REG = ulTimerCountsForOneTick - 1UL;
+
+ /* Re-enable interrupts - see comments above __disable_irq() call
+ above. */
+ __enable_irq();
+ }
+ else
+ {
+ /* Set the new reload value. */
+ portNVIC_SYSTICK_LOAD_REG = ulReloadValue;
+
+ /* Clear the SysTick count flag and set the count value back to
+ zero. */
+ portNVIC_SYSTICK_CURRENT_VALUE_REG = 0UL;
+
+ /* Restart SysTick. */
+ portNVIC_SYSTICK_CTRL_REG |= portNVIC_SYSTICK_ENABLE_BIT;
+
+ /* Sleep until something happens. configPRE_SLEEP_PROCESSING() can
+ set its parameter to 0 to indicate that its implementation contains
+ its own wait for interrupt or wait for event instruction, and so wfi
+ should not be executed again. However, the original expected idle
+ time variable must remain unmodified, so a copy is taken. */
+ xModifiableIdleTime = xExpectedIdleTime;
+ configPRE_SLEEP_PROCESSING( xModifiableIdleTime );
+ if( xModifiableIdleTime > 0 )
+ {
+ __dsb( portSY_FULL_READ_WRITE );
+ __wfi();
+ __isb( portSY_FULL_READ_WRITE );
+ }
+ configPOST_SLEEP_PROCESSING( xExpectedIdleTime );
+
+ /* Stop SysTick. Again, the time the SysTick is stopped for is
+ accounted for as best it can be, but using the tickless mode will
+ inevitably result in some tiny drift of the time maintained by the
+ kernel with respect to calendar time. */
+ ulSysTickCTRL = portNVIC_SYSTICK_CTRL_REG;
+ portNVIC_SYSTICK_CTRL_REG = ( ulSysTickCTRL & ~portNVIC_SYSTICK_ENABLE_BIT );
+
+ /* Re-enable interrupts - see comments above __disable_irq() call
+ above. */
+ __enable_irq();
+
+ if( ( ulSysTickCTRL & portNVIC_SYSTICK_COUNT_FLAG_BIT ) != 0 )
+ {
+ uint32_t ulCalculatedLoadValue;
+
+ /* The tick interrupt has already executed, and the SysTick
+ count reloaded with ulReloadValue. Reset the
+ portNVIC_SYSTICK_LOAD_REG with whatever remains of this tick
+ period. */
+ ulCalculatedLoadValue = ( ulTimerCountsForOneTick - 1UL ) - ( ulReloadValue - portNVIC_SYSTICK_CURRENT_VALUE_REG );
+
+ /* Don't allow a tiny value, or values that have somehow
+ underflowed because the post sleep hook did something
+ that took too long. */
+ if( ( ulCalculatedLoadValue < ulStoppedTimerCompensation ) || ( ulCalculatedLoadValue > ulTimerCountsForOneTick ) )
+ {
+ ulCalculatedLoadValue = ( ulTimerCountsForOneTick - 1UL );
+ }
+
+ portNVIC_SYSTICK_LOAD_REG = ulCalculatedLoadValue;
+
+ /* The tick interrupt handler will already have pended the tick
+ processing in the kernel. As the pending tick will be
+ processed as soon as this function exits, the tick value
+ maintained by the tick is stepped forward by one less than the
+ time spent waiting. */
+ ulCompleteTickPeriods = xExpectedIdleTime - 1UL;
+ }
+ else
+ {
+ /* Something other than the tick interrupt ended the sleep.
+ Work out how long the sleep lasted rounded to complete tick
+ periods (not the ulReload value which accounted for part
+ ticks). */
+ ulCompletedSysTickDecrements = ( xExpectedIdleTime * ulTimerCountsForOneTick ) - portNVIC_SYSTICK_CURRENT_VALUE_REG;
+
+ /* How many complete tick periods passed while the processor
+ was waiting? */
+ ulCompleteTickPeriods = ulCompletedSysTickDecrements / ulTimerCountsForOneTick;
+
+ /* The reload value is set to whatever fraction of a single tick
+ period remains. */
+ portNVIC_SYSTICK_LOAD_REG = ( ( ulCompleteTickPeriods + 1 ) * ulTimerCountsForOneTick ) - ulCompletedSysTickDecrements;
+ }
+
+ /* Restart SysTick so it runs from portNVIC_SYSTICK_LOAD_REG
+ again, then set portNVIC_SYSTICK_LOAD_REG back to its standard
+ value. The critical section is used to ensure the tick interrupt
+ can only execute once in the case that the reload register is near
+ zero. */
+ portNVIC_SYSTICK_CURRENT_VALUE_REG = 0UL;
+ portENTER_CRITICAL();
+ {
+ portNVIC_SYSTICK_CTRL_REG |= portNVIC_SYSTICK_ENABLE_BIT;
+ vTaskStepTick( ulCompleteTickPeriods );
+ portNVIC_SYSTICK_LOAD_REG = ulTimerCountsForOneTick - 1UL;
+ }
+ portEXIT_CRITICAL();
+ }
+ }
+
+#endif /* #if configUSE_TICKLESS_IDLE */
+
+/*-----------------------------------------------------------*/
+
+/*
+ * Setup the SysTick timer to generate the tick interrupts at the required
+ * frequency.
+ */
+#if configOVERRIDE_DEFAULT_TICK_CONFIGURATION == 0
+
+ void vPortSetupTimerInterrupt( void )
+ {
+ /* Calculate the constants required to configure the tick interrupt. */
+ #if configUSE_TICKLESS_IDLE == 1
+ {
+ ulTimerCountsForOneTick = ( configSYSTICK_CLOCK_HZ / configTICK_RATE_HZ );
+ xMaximumPossibleSuppressedTicks = portMAX_24_BIT_NUMBER / ulTimerCountsForOneTick;
+ ulStoppedTimerCompensation = portMISSED_COUNTS_FACTOR / ( configCPU_CLOCK_HZ / configSYSTICK_CLOCK_HZ );
+ }
+ #endif /* configUSE_TICKLESS_IDLE */
+
+ /* Configure SysTick to interrupt at the requested rate. */
+ portNVIC_SYSTICK_LOAD_REG = ( configSYSTICK_CLOCK_HZ / configTICK_RATE_HZ ) - 1UL;
+ portNVIC_SYSTICK_CTRL_REG = ( portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT | portNVIC_SYSTICK_ENABLE_BIT );
+ }
+
+#endif /* configOVERRIDE_DEFAULT_TICK_CONFIGURATION */
+/*-----------------------------------------------------------*/
+
+__asm uint32_t vPortGetIPSR( void )
+{
+ PRESERVE8
+
+ mrs r0, ipsr
+ bx r14
+}
+/*-----------------------------------------------------------*/
+
+#if( configASSERT_DEFINED == 1 )
+
+ void vPortValidateInterruptPriority( void )
+ {
+ uint32_t ulCurrentInterrupt;
+ uint8_t ucCurrentPriority;
+
+ /* Obtain the number of the currently executing interrupt. */
+ ulCurrentInterrupt = vPortGetIPSR();
+
+ /* Is the interrupt number a user defined interrupt? */
+ if( ulCurrentInterrupt >= portFIRST_USER_INTERRUPT_NUMBER )
+ {
+ /* Look up the interrupt's priority. */
+ ucCurrentPriority = pcInterruptPriorityRegisters[ ulCurrentInterrupt ];
+
+ /* The following assertion will fail if a service routine (ISR) for
+ an interrupt that has been assigned a priority above
+ configMAX_SYSCALL_INTERRUPT_PRIORITY calls an ISR safe FreeRTOS API
+ function. ISR safe FreeRTOS API functions must *only* be called
+ from interrupts that have been assigned a priority at or below
+ configMAX_SYSCALL_INTERRUPT_PRIORITY.
+
+ Numerically low interrupt priority numbers represent logically high
+ interrupt priorities, therefore the priority of the interrupt must
+ be set to a value equal to or numerically *higher* than
+ configMAX_SYSCALL_INTERRUPT_PRIORITY.
+
+ Interrupts that use the FreeRTOS API must not be left at their
+ default priority of zero as that is the highest possible priority,
+ which is guaranteed to be above configMAX_SYSCALL_INTERRUPT_PRIORITY,
+ and therefore also guaranteed to be invalid.
+
+ FreeRTOS maintains separate thread and ISR API functions to ensure
+ interrupt entry is as fast and simple as possible.
+
+ The following links provide detailed information:
+ http://www.freertos.org/RTOS-Cortex-M3-M4.html
+ http://www.freertos.org/FAQHelp.html */
+ configASSERT( ucCurrentPriority >= ucMaxSysCallPriority );
+ }
+
+ /* Priority grouping: The interrupt controller (NVIC) allows the bits
+ that define each interrupt's priority to be split between bits that
+ define the interrupt's pre-emption priority bits and bits that define
+ the interrupt's sub-priority. For simplicity all bits must be defined
+ to be pre-emption priority bits. The following assertion will fail if
+ this is not the case (if some bits represent a sub-priority).
+
+ If the application only uses CMSIS libraries for interrupt
+ configuration then the correct setting can be achieved on all Cortex-M
+ devices by calling NVIC_SetPriorityGrouping( 0 ); before starting the
+ scheduler. Note however that some vendor specific peripheral libraries
+ assume a non-zero priority group setting, in which cases using a value
+ of zero will result in unpredicable behaviour. */
+ configASSERT( ( portAIRCR_REG & portPRIORITY_GROUP_MASK ) <= ulMaxPRIGROUPValue );
+ }
+
+#endif /* configASSERT_DEFINED */
+
+
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