diff options
Diffstat (limited to 'freertos/src/portable/GCC/ARM_CM3/fsl_tickless_systick.c')
-rw-r--r-- | freertos/src/portable/GCC/ARM_CM3/fsl_tickless_systick.c | 273 |
1 files changed, 0 insertions, 273 deletions
diff --git a/freertos/src/portable/GCC/ARM_CM3/fsl_tickless_systick.c b/freertos/src/portable/GCC/ARM_CM3/fsl_tickless_systick.c deleted file mode 100644 index c75613d..0000000 --- a/freertos/src/portable/GCC/ARM_CM3/fsl_tickless_systick.c +++ /dev/null @@ -1,273 +0,0 @@ -/* - FreeRTOS V9.0.0 - Copyright (C) 2016 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! -*/ -#include "FreeRTOS.h" -#include "task.h" -#include "fsl_tickless_generic.h" - -extern uint32_t SystemCoreClock; /* in Kinetis SDK, this contains the system core clock speed */ - -/* - * 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 */ - - -/*-----------------------------------------------------------*/ -#if configUSE_TICKLESS_IDLE == 1 - - __attribute__((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; - } - if (xExpectedIdleTime == 0) return; - /* 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. */ - __asm volatile( "cpsid i" ); - __asm volatile( "dsb" ); - __asm volatile( "isb" ); - - /* 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 the cpsid instruction() - above. */ - __asm volatile( "cpsie i" ); - } - 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 ) - { - __asm volatile( "dsb" ); - __asm volatile( "wfi" ); - __asm volatile( "isb" ); - } - 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 the cpsid instruction() - above. */ - __asm volatile( "cpsie i" ); - - 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 + 1UL ) * 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. - */ -__attribute__(( weak )) 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_CURRENT_VALUE_REG = 0UL; - portNVIC_SYSTICK_CTRL_REG = ( portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT | portNVIC_SYSTICK_ENABLE_BIT ); -} |