X-Git-Url: https://git.sur5r.net/?a=blobdiff_plain;f=FreeRTOS%2FSource%2Fportable%2FCCS%2FARM_CM4F%2Fport.c;h=9b8768fc89ffaac5818070646ad8ef59b95e532e;hb=b15dfacb6026af3b0ba697e5753844923b468d2b;hp=bd4365f9eac3dea6adf44b58fb6b8564029f0c4c;hpb=f60b252c8f21e9198438dd0b7c7623f269aa6f1a;p=freertos diff --git a/FreeRTOS/Source/portable/CCS/ARM_CM4F/port.c b/FreeRTOS/Source/portable/CCS/ARM_CM4F/port.c index bd4365f9e..9b8768fc8 100644 --- a/FreeRTOS/Source/portable/CCS/ARM_CM4F/port.c +++ b/FreeRTOS/Source/portable/CCS/ARM_CM4F/port.c @@ -1,71 +1,29 @@ /* - FreeRTOS V9.0.0rc1 - 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! -*/ + * FreeRTOS Kernel V10.3.0 + * Copyright (C) 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved. + * + * Permission is hereby granted, free of charge, to any person obtaining a copy of + * this software and associated documentation files (the "Software"), to deal in + * the Software without restriction, including without limitation the rights to + * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of + * the Software, and to permit persons to whom the Software is furnished to do so, + * subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all + * copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS + * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR + * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER + * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + * + * http://www.FreeRTOS.org + * http://aws.amazon.com/freertos + * + * 1 tab == 4 spaces! + */ /*----------------------------------------------------------- * Implementation of functions defined in portable.h for the ARM CM4F port. @@ -79,7 +37,7 @@ #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 +#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 @@ -127,7 +85,7 @@ /* Constants required to set up the initial stack. */ #define portINITIAL_XPSR ( 0x01000000 ) -#define portINITIAL_EXEC_RETURN ( 0xfffffffd ) +#define portINITIAL_EXC_RETURN ( 0xfffffffd ) /* The systick is a 24-bit counter. */ #define portMAX_24_BIT_NUMBER ( 0xffffffUL ) @@ -137,13 +95,9 @@ occurred while the SysTick counter is stopped during tickless idle calculations. */ #define portMISSED_COUNTS_FACTOR ( 45UL ) -/* Required to allow portasm.asm access the configMAX_SYSCALL_INTERRUPT_PRIORITY -setting. */ -const uint32_t ulMaxSyscallInterruptPriority = configMAX_SYSCALL_INTERRUPT_PRIORITY; - -/* Each task maintains its own interrupt status in the critical nesting -variable. */ -static UBaseType_t uxCriticalNesting = 0xaaaaaaaa; +/* For strict compliance with the Cortex-M spec the task start address should +have bit-0 clear, as it is loaded into the PC on exit from an ISR. */ +#define portSTART_ADDRESS_MASK ( ( StackType_t ) 0xfffffffeUL ) /* * Setup the timer to generate the tick interrupts. The implementation in this @@ -174,10 +128,18 @@ static void prvTaskExitError( void ); /*-----------------------------------------------------------*/ +/* Required to allow portasm.asm access the configMAX_SYSCALL_INTERRUPT_PRIORITY +setting. */ +const uint32_t ulMaxSyscallInterruptPriority = configMAX_SYSCALL_INTERRUPT_PRIORITY; + +/* Each task maintains its own interrupt status in the critical nesting +variable. */ +static UBaseType_t uxCriticalNesting = 0xaaaaaaaa; + /* * The number of SysTick increments that make up one tick period. */ -#if configUSE_TICKLESS_IDLE == 1 +#if( configUSE_TICKLESS_IDLE == 1 ) static uint32_t ulTimerCountsForOneTick = 0; #endif /* configUSE_TICKLESS_IDLE */ @@ -185,7 +147,7 @@ static void prvTaskExitError( void ); * 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 +#if( configUSE_TICKLESS_IDLE == 1 ) static uint32_t xMaximumPossibleSuppressedTicks = 0; #endif /* configUSE_TICKLESS_IDLE */ @@ -193,7 +155,7 @@ static void prvTaskExitError( void ); * Compensate for the CPU cycles that pass while the SysTick is stopped (low * power functionality only. */ -#if configUSE_TICKLESS_IDLE == 1 +#if( configUSE_TICKLESS_IDLE == 1 ) static uint32_t ulStoppedTimerCompensation = 0; #endif /* configUSE_TICKLESS_IDLE */ @@ -224,7 +186,7 @@ StackType_t *pxPortInitialiseStack( StackType_t *pxTopOfStack, TaskFunction_t px *pxTopOfStack = portINITIAL_XPSR; /* xPSR */ pxTopOfStack--; - *pxTopOfStack = ( StackType_t ) pxCode; /* PC */ + *pxTopOfStack = ( ( StackType_t ) pxCode ) & portSTART_ADDRESS_MASK; /* PC */ pxTopOfStack--; *pxTopOfStack = ( StackType_t ) prvTaskExitError; /* LR */ @@ -235,7 +197,7 @@ StackType_t *pxPortInitialiseStack( StackType_t *pxTopOfStack, TaskFunction_t px /* A save method is being used that requires each task to maintain its own exec return value. */ pxTopOfStack--; - *pxTopOfStack = portINITIAL_EXEC_RETURN; + *pxTopOfStack = portINITIAL_EXC_RETURN; pxTopOfStack -= 8; /* R11, R10, R9, R8, R7, R6, R5 and R4. */ @@ -295,6 +257,24 @@ BaseType_t xPortStartScheduler( void ) ucMaxPriorityValue <<= ( uint8_t ) 0x01; } + #ifdef __NVIC_PRIO_BITS + { + /* Check the CMSIS configuration that defines the number of + priority bits matches the number of priority bits actually queried + from the hardware. */ + configASSERT( ( portMAX_PRIGROUP_BITS - ulMaxPRIGROUPValue ) == __NVIC_PRIO_BITS ); + } + #endif + + #ifdef configPRIO_BITS + { + /* Check the FreeRTOS configuration that defines the number of + priority bits matches the number of priority bits actually queried + from the hardware. */ + configASSERT( ( portMAX_PRIGROUP_BITS - ulMaxPRIGROUPValue ) == configPRIO_BITS ); + } + #endif + /* Shift the priority group value back to its position within the AIRCR register. */ ulMaxPRIGROUPValue <<= portPRIGROUP_SHIFT; @@ -387,12 +367,12 @@ void xPortSysTickHandler( void ) } /*-----------------------------------------------------------*/ -#if configUSE_TICKLESS_IDLE == 1 +#if( configUSE_TICKLESS_IDLE == 1 ) #pragma WEAK( vPortSuppressTicksAndSleep ) void vPortSuppressTicksAndSleep( TickType_t xExpectedIdleTime ) { - uint32_t ulReloadValue, ulCompleteTickPeriods, ulCompletedSysTickDecrements, ulSysTickCTRL; + uint32_t ulReloadValue, ulCompleteTickPeriods, ulCompletedSysTickDecrements; TickType_t xModifiableIdleTime; /* Make sure the SysTick reload value does not overflow the counter. */ @@ -419,6 +399,9 @@ void xPortSysTickHandler( void ) /* Enter a critical section but don't use the taskENTER_CRITICAL() method as that will mask interrupts that should exit sleep mode. */ __asm( " cpsid i" ); + __asm( " dsb" ); + __asm( " isb" ); + /* If a context switch is pending or a task is waiting for the scheduler to be unsuspended then abandon the low power entry. */ @@ -466,23 +449,41 @@ void xPortSysTickHandler( void ) } 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_interrupt() - call above. */ + /* Re-enable interrupts to allow the interrupt that brought the MCU + out of sleep mode to execute immediately. see comments above + __disable_interrupt() call above. */ __asm( " cpsie i" ); - - if( ( ulSysTickCTRL & portNVIC_SYSTICK_COUNT_FLAG_BIT ) != 0 ) + __asm( " dsb" ); + __asm( " isb" ); + + /* Disable interrupts again because the clock is about to be stopped + and interrupts that execute while the clock is stopped will increase + any slippage between the time maintained by the RTOS and calendar + time. */ + __asm( " cpsid i" ); + __asm( " dsb" ); + __asm( " isb" ); + + /* Disable the SysTick clock without reading the + portNVIC_SYSTICK_CTRL_REG register to ensure the + portNVIC_SYSTICK_COUNT_FLAG_BIT is not cleared if it is set. 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*/ + portNVIC_SYSTICK_CTRL_REG = ( portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT ); + + /* Determine if the SysTick clock has already counted to zero and + been set back to the current reload value (the reload back being + correct for the entire expected idle time) or if the SysTick is yet + to count to zero (in which case an interrupt other than the SysTick + must have brought the system out of sleep mode). */ + if( ( portNVIC_SYSTICK_CTRL_REG & portNVIC_SYSTICK_COUNT_FLAG_BIT ) != 0 ) { uint32_t ulCalculatedLoadValue; - /* The tick interrupt has already executed, and the SysTick - count reloaded with ulReloadValue. Reset the + /* The tick interrupt is already pending, 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 ); @@ -497,11 +498,9 @@ void xPortSysTickHandler( void ) 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. */ + /* 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 @@ -523,21 +522,18 @@ void xPortSysTickHandler( void ) /* 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. */ + value. */ 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(); + portNVIC_SYSTICK_CTRL_REG |= portNVIC_SYSTICK_ENABLE_BIT; + vTaskStepTick( ulCompleteTickPeriods ); + portNVIC_SYSTICK_LOAD_REG = ulTimerCountsForOneTick - 1UL; + + /* Exit with interrupts enabled. */ + __asm( " cpsie i" ); } } -#endif /* #if configUSE_TICKLESS_IDLE */ +#endif /* configUSE_TICKLESS_IDLE */ /*-----------------------------------------------------------*/ /* @@ -548,7 +544,7 @@ void xPortSysTickHandler( void ) void vPortSetupTimerInterrupt( void ) { /* Calculate the constants required to configure the tick interrupt. */ - #if configUSE_TICKLESS_IDLE == 1 + #if( configUSE_TICKLESS_IDLE == 1 ) { ulTimerCountsForOneTick = ( configSYSTICK_CLOCK_HZ / configTICK_RATE_HZ ); xMaximumPossibleSuppressedTicks = portMAX_24_BIT_NUMBER / ulTimerCountsForOneTick; @@ -556,6 +552,10 @@ void vPortSetupTimerInterrupt( void ) } #endif /* configUSE_TICKLESS_IDLE */ + /* Stop and clear the SysTick. */ + portNVIC_SYSTICK_CTRL_REG = 0UL; + portNVIC_SYSTICK_CURRENT_VALUE_REG = 0UL; + /* 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 ); @@ -616,7 +616,7 @@ void vPortSetupTimerInterrupt( void ) 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. */ + of zero will result in unpredictable behaviour. */ configASSERT( ( portAIRCR_REG & portPRIORITY_GROUP_MASK ) <= ulMaxPRIGROUPValue ); }