/* * FreeRTOS Kernel V11.1.0 * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved. * * SPDX-License-Identifier: MIT * * 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. * * https://www.FreeRTOS.org * https://github.com/FreeRTOS * */ /* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE prevents task.h from redefining * all the API functions to use the MPU wrappers. That should only be done when * task.h is included from an application file. */ #define MPU_WRAPPERS_INCLUDED_FROM_API_FILE /* Scheduler includes. */ #include "FreeRTOS.h" #include "task.h" /* MPU includes. */ #include "mpu_wrappers.h" #include "mpu_syscall_numbers.h" /* Portasm includes. */ #include "portasm.h" #undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE /*-----------------------------------------------------------*/ /** * @brief Prototype of all Interrupt Service Routines (ISRs). */ typedef void ( * portISR_t )( void ); /*-----------------------------------------------------------*/ /** * @brief Constants required to manipulate the NVIC. */ #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_SHPR3_REG ( *( ( volatile uint32_t * ) 0xe000ed20 ) ) #define portNVIC_SHPR2_REG ( *( ( volatile uint32_t * ) 0xe000ed1c ) ) #define portNVIC_SYSTICK_ENABLE_BIT ( 1UL << 0UL ) #define portNVIC_SYSTICK_INT_BIT ( 1UL << 1UL ) #define portNVIC_SYSTICK_CLK_BIT ( 1UL << 2UL ) #define portNVIC_SYSTICK_COUNT_FLAG_BIT ( 1UL << 16UL ) #define portNVIC_PEND_SYSTICK_CLEAR_BIT ( 1UL << 25UL ) #define portNVIC_PEND_SYSTICK_SET_BIT ( 1UL << 26UL ) #define portMIN_INTERRUPT_PRIORITY ( 255UL ) #define portNVIC_PENDSV_PRI ( portMIN_INTERRUPT_PRIORITY << 16UL ) #define portNVIC_SYSTICK_PRI ( portMIN_INTERRUPT_PRIORITY << 24UL ) /*-----------------------------------------------------------*/ /** * @brief Constants required to manipulate the SCB. */ #define portSCB_VTOR_REG ( *( ( portISR_t ** ) 0xe000ed08 ) ) #define portSCB_SYS_HANDLER_CTRL_STATE_REG ( *( ( volatile uint32_t * ) 0xe000ed24 ) ) #define portSCB_MEM_FAULT_ENABLE_BIT ( 1UL << 16UL ) /*-----------------------------------------------------------*/ /** * @brief Constants used to check the installation of the FreeRTOS interrupt handlers. */ #define portVECTOR_INDEX_SVC ( 11 ) #define portVECTOR_INDEX_PENDSV ( 14 ) /*-----------------------------------------------------------*/ /** * @brief Constants used during system call enter and exit. */ #define portPSR_STACK_PADDING_MASK ( 1UL << 9UL ) #define portEXC_RETURN_STACK_FRAME_TYPE_MASK ( 1UL << 4UL ) /*-----------------------------------------------------------*/ /** * @brief Offsets in the stack to the parameters when inside the SVC handler. */ #define portOFFSET_TO_LR ( 5 ) #define portOFFSET_TO_PC ( 6 ) #define portOFFSET_TO_PSR ( 7 ) /*-----------------------------------------------------------*/ /** * @brief Constants required to manipulate the MPU. */ #define portMPU_TYPE_REG ( *( ( volatile uint32_t * ) 0xe000ed90 ) ) #define portMPU_CTRL_REG ( *( ( volatile uint32_t * ) 0xe000ed94 ) ) #define portMPU_RBAR_REG ( *( ( volatile uint32_t * ) 0xe000ed9c ) ) #define portMPU_RASR_REG ( *( ( volatile uint32_t * ) 0xe000eda0 ) ) /* MPU Region Attribute and Size Register (RASR) bitmasks. */ #define portMPU_RASR_AP_BITMASK ( 0x7UL << 24UL ) #define portMPU_RASR_S_C_B_BITMASK ( 0x7UL ) #define portMPU_RASR_S_C_B_LOCATION ( 16UL ) #define portMPU_RASR_SIZE_BITMASK ( 0x1FUL << 1UL ) #define portMPU_RASR_REGION_ENABLE_BITMASK ( 0x1UL ) /* MPU Region Base Address Register (RBAR) bitmasks. */ #define portMPU_RBAR_ADDRESS_BITMASK ( 0xFFFFFF00UL ) #define portMPU_RBAR_REGION_NUMBER_VALID_BITMASK ( 0x1UL << 4UL ) #define portMPU_RBAR_REGION_NUMBER_BITMASK ( 0x0000000FUL ) /* MPU Control Register (MPU_CTRL) bitmasks. */ #define portMPU_CTRL_ENABLE_BITMASK ( 0x1UL ) #define portMPU_CTRL_PRIV_BACKGROUND_ENABLE_BITMASK ( 0x1UL << 2UL ) /* PRIVDEFENA bit. */ /* Expected value of the portMPU_TYPE register. */ #define portEXPECTED_MPU_TYPE_VALUE ( 0x8UL << 8UL ) /* 8 DREGION unified. */ /* Extract first address of the MPU region as encoded in the * RBAR (Region Base Address Register) value. */ #define portEXTRACT_FIRST_ADDRESS_FROM_RBAR( rbar ) \ ( ( rbar ) & portMPU_RBAR_ADDRESS_BITMASK ) /* Extract size of the MPU region as encoded in the * RASR (Region Attribute and Size Register) value. */ #define portEXTRACT_REGION_SIZE_FROM_RASR( rasr ) \ ( 1 << ( ( ( ( rasr ) & portMPU_RASR_SIZE_BITMASK ) >> 1 )+ 1 ) ) /* Does addr lies within [start, end] address range? */ #define portIS_ADDRESS_WITHIN_RANGE( addr, start, end ) \ ( ( ( addr ) >= ( start ) ) && ( ( addr ) <= ( end ) ) ) /* Is the access request satisfied by the available permissions? */ #define portIS_AUTHORIZED( accessRequest, permissions ) \ ( ( ( permissions ) & ( accessRequest ) ) == accessRequest ) /* Max value that fits in a uint32_t type. */ #define portUINT32_MAX ( ~( ( uint32_t ) 0 ) ) /* Check if adding a and b will result in overflow. */ #define portADD_UINT32_WILL_OVERFLOW( a, b ) ( ( a ) > ( portUINT32_MAX - ( b ) ) ) /*-----------------------------------------------------------*/ /** * @brief The maximum 24-bit number. * * It is needed because the systick is a 24-bit counter. */ #define portMAX_24_BIT_NUMBER ( 0xffffffUL ) /** * @brief 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 ( 94UL ) /*-----------------------------------------------------------*/ /** * @brief Constants required to set up the initial stack. */ #define portINITIAL_XPSR ( 0x01000000 ) /** * @brief Initial EXC_RETURN value. * * FF FF FF FD * 1111 1111 1111 1111 1111 1111 1111 1101 * * Bit[3] - 1 --> Return to the Thread mode. * Bit[2] - 1 --> Restore registers from the process stack. * Bit[1] - 0 --> Reserved, 0. * Bit[0] - 0 --> Reserved, 1. */ #define portINITIAL_EXC_RETURN ( 0xfffffffdUL ) /** * @brief CONTROL register privileged bit mask. * * Bit[0] in CONTROL register tells the privilege: * Bit[0] = 0 ==> The task is privileged. * Bit[0] = 1 ==> The task is not privileged. */ #define portCONTROL_PRIVILEGED_MASK ( 1UL << 0UL ) /** * @brief Initial CONTROL register values. */ #define portINITIAL_CONTROL_UNPRIVILEGED ( 0x3 ) #define portINITIAL_CONTROL_PRIVILEGED ( 0x2 ) /** * @brief Let the user override the default SysTick clock rate. If defined by the * user, this symbol must equal the SysTick clock rate when the CLK bit is 0 in the * configuration register. */ #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_CONFIG ( portNVIC_SYSTICK_CLK_BIT ) #else /* Select the option to clock SysTick not at the same frequency as the core. */ #define portNVIC_SYSTICK_CLK_BIT_CONFIG ( 0 ) #endif /** * @brief Let the user override the pre-loading of the initial LR with the * address of prvTaskExitError() in case it messes up unwinding of the stack * in the debugger. */ #ifdef configTASK_RETURN_ADDRESS #define portTASK_RETURN_ADDRESS configTASK_RETURN_ADDRESS #else #define portTASK_RETURN_ADDRESS prvTaskExitError #endif /** * @brief If portPRELOAD_REGISTERS then registers will be given an initial value * when a task is created. This helps in debugging at the cost of code size. */ #define portPRELOAD_REGISTERS 1 /*-----------------------------------------------------------*/ /** * @brief Used to catch tasks that attempt to return from their implementing * function. */ static void prvTaskExitError( void ); #if ( configENABLE_MPU == 1 ) /** * @brief Setup the Memory Protection Unit (MPU). */ static void prvSetupMPU( void ) PRIVILEGED_FUNCTION; #endif /* configENABLE_MPU */ /** * @brief 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 ) PRIVILEGED_FUNCTION; /** * @brief Checks whether the current execution context is interrupt. * * @return pdTRUE if the current execution context is interrupt, pdFALSE * otherwise. */ BaseType_t xPortIsInsideInterrupt( void ); /** * @brief Yield the processor. */ void vPortYield( void ) PRIVILEGED_FUNCTION; /** * @brief Enter critical section. */ void vPortEnterCritical( void ) PRIVILEGED_FUNCTION; /** * @brief Exit from critical section. */ void vPortExitCritical( void ) PRIVILEGED_FUNCTION; /** * @brief SysTick handler. */ void SysTick_Handler( void ) PRIVILEGED_FUNCTION; /** * @brief C part of SVC handler. */ portDONT_DISCARD void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) PRIVILEGED_FUNCTION; #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) /** * @brief Sets up the system call stack so that upon returning from * SVC, the system call stack is used. * * @param pulTaskStack The current SP when the SVC was raised. * @param ulLR The value of Link Register (EXC_RETURN) in the SVC handler. * @param ucSystemCallNumber The system call number of the system call. */ void vSystemCallEnter( uint32_t * pulTaskStack, uint32_t ulLR, uint8_t ucSystemCallNumber ) PRIVILEGED_FUNCTION; #endif /* ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) */ #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) /** * @brief Raise SVC for exiting from a system call. */ void vRequestSystemCallExit( void ) __attribute__( ( naked ) ) PRIVILEGED_FUNCTION; #endif /* ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) */ #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) /** * @brief Sets up the task stack so that upon returning from * SVC, the task stack is used again. * * @param pulSystemCallStack The current SP when the SVC was raised. * @param ulLR The value of Link Register (EXC_RETURN) in the SVC handler. */ void vSystemCallExit( uint32_t * pulSystemCallStack, uint32_t ulLR ) PRIVILEGED_FUNCTION; #endif /* ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) */ #if ( configENABLE_MPU == 1 ) /** * @brief Checks whether or not the calling task is privileged. * * @return pdTRUE if the calling task is privileged, pdFALSE otherwise. */ BaseType_t xPortIsTaskPrivileged( void ) PRIVILEGED_FUNCTION; #endif /* configENABLE_MPU == 1 */ /*-----------------------------------------------------------*/ #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) /** * @brief This variable is set to pdTRUE when the scheduler is started. */ PRIVILEGED_DATA static BaseType_t xSchedulerRunning = pdFALSE; #endif /** * @brief Each task maintains its own interrupt status in the critical nesting * variable. */ PRIVILEGED_DATA static volatile uint32_t ulCriticalNesting = 0xaaaaaaaaUL; #if ( configUSE_TICKLESS_IDLE == 1 ) /** * @brief The number of SysTick increments that make up one tick period. */ PRIVILEGED_DATA static uint32_t ulTimerCountsForOneTick = 0; /** * @brief The maximum number of tick periods that can be suppressed is * limited by the 24 bit resolution of the SysTick timer. */ PRIVILEGED_DATA static uint32_t xMaximumPossibleSuppressedTicks = 0; /** * @brief Compensate for the CPU cycles that pass while the SysTick is * stopped (low power functionality only). */ PRIVILEGED_DATA 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, ulSysTickDecrementsLeft; TickType_t xModifiableIdleTime; /* Make sure the SysTick reload value does not overflow the counter. */ if( xExpectedIdleTime > xMaximumPossibleSuppressedTicks ) { xExpectedIdleTime = xMaximumPossibleSuppressedTicks; } /* 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" ::: "memory" ); __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 ) { /* Re-enable interrupts - see comments above the cpsid instruction * above. */ __asm volatile ( "cpsie i" ::: "memory" ); } else { /* 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_CLK_BIT_CONFIG | portNVIC_SYSTICK_INT_BIT ); /* Use the SysTick current-value register to determine the number of * SysTick decrements remaining until the next tick interrupt. If the * current-value register is zero, then there are actually * ulTimerCountsForOneTick decrements remaining, not zero, because the * SysTick requests the interrupt when decrementing from 1 to 0. */ ulSysTickDecrementsLeft = portNVIC_SYSTICK_CURRENT_VALUE_REG; if( ulSysTickDecrementsLeft == 0 ) { ulSysTickDecrementsLeft = ulTimerCountsForOneTick; } /* Calculate the reload value required to wait xExpectedIdleTime * tick periods. -1 is used because this code normally executes part * way through the first tick period. But if the SysTick IRQ is now * pending, then clear the IRQ, suppressing the first tick, and correct * the reload value to reflect that the second tick period is already * underway. The expected idle time is always at least two ticks. */ ulReloadValue = ulSysTickDecrementsLeft + ( ulTimerCountsForOneTick * ( xExpectedIdleTime - 1UL ) ); if( ( portNVIC_INT_CTRL_REG & portNVIC_PEND_SYSTICK_SET_BIT ) != 0 ) { portNVIC_INT_CTRL_REG = portNVIC_PEND_SYSTICK_CLEAR_BIT; ulReloadValue -= ulTimerCountsForOneTick; } if( ulReloadValue > ulStoppedTimerCompensation ) { ulReloadValue -= ulStoppedTimerCompensation; } /* 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" ::: "memory" ); __asm volatile ( "wfi" ); __asm volatile ( "isb" ); } configPOST_SLEEP_PROCESSING( xExpectedIdleTime ); /* Re-enable interrupts to allow the interrupt that brought the MCU * out of sleep mode to execute immediately. See comments above * the cpsid instruction above. */ __asm volatile ( "cpsie i" ::: "memory" ); __asm volatile ( "dsb" ); __asm volatile ( "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 volatile ( "cpsid i" ::: "memory" ); __asm volatile ( "dsb" ); __asm volatile ( "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_CONFIG | portNVIC_SYSTICK_INT_BIT ); /* Determine whether the SysTick has already counted to zero. */ if( ( portNVIC_SYSTICK_CTRL_REG & portNVIC_SYSTICK_COUNT_FLAG_BIT ) != 0 ) { uint32_t ulCalculatedLoadValue; /* The tick interrupt ended the sleep (or is now pending), and * a new tick period has started. Reset portNVIC_SYSTICK_LOAD_REG * with whatever remains of the new 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 or because the SysTick current-value register * is zero. */ if( ( ulCalculatedLoadValue <= ulStoppedTimerCompensation ) || ( ulCalculatedLoadValue > ulTimerCountsForOneTick ) ) { ulCalculatedLoadValue = ( ulTimerCountsForOneTick - 1UL ); } portNVIC_SYSTICK_LOAD_REG = ulCalculatedLoadValue; /* 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. */ /* Use the SysTick current-value register to determine the * number of SysTick decrements remaining until the expected idle * time would have ended. */ ulSysTickDecrementsLeft = portNVIC_SYSTICK_CURRENT_VALUE_REG; #if ( portNVIC_SYSTICK_CLK_BIT_CONFIG != portNVIC_SYSTICK_CLK_BIT ) { /* If the SysTick is not using the core clock, the current- * value register might still be zero here. In that case, the * SysTick didn't load from the reload register, and there are * ulReloadValue decrements remaining in the expected idle * time, not zero. */ if( ulSysTickDecrementsLeft == 0 ) { ulSysTickDecrementsLeft = ulReloadValue; } } #endif /* portNVIC_SYSTICK_CLK_BIT_CONFIG */ /* Work out how long the sleep lasted rounded to complete tick * periods (not the ulReload value which accounted for part * ticks). */ ulCompletedSysTickDecrements = ( xExpectedIdleTime * ulTimerCountsForOneTick ) - ulSysTickDecrementsLeft; /* 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. If * the SysTick is not using the core clock, temporarily configure it to * use the core clock. This configuration forces the SysTick to load * from portNVIC_SYSTICK_LOAD_REG immediately instead of at the next * cycle of the other clock. Then portNVIC_SYSTICK_LOAD_REG is ready * to receive the standard value immediately. */ portNVIC_SYSTICK_CURRENT_VALUE_REG = 0UL; portNVIC_SYSTICK_CTRL_REG = portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT | portNVIC_SYSTICK_ENABLE_BIT; #if ( portNVIC_SYSTICK_CLK_BIT_CONFIG == portNVIC_SYSTICK_CLK_BIT ) { portNVIC_SYSTICK_LOAD_REG = ulTimerCountsForOneTick - 1UL; } #else { /* The temporary usage of the core clock has served its purpose, * as described above. Resume usage of the other clock. */ portNVIC_SYSTICK_CTRL_REG = portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT; if( ( portNVIC_SYSTICK_CTRL_REG & portNVIC_SYSTICK_COUNT_FLAG_BIT ) != 0 ) { /* The partial tick period already ended. Be sure the SysTick * counts it only once. */ portNVIC_SYSTICK_CURRENT_VALUE_REG = 0; } portNVIC_SYSTICK_LOAD_REG = ulTimerCountsForOneTick - 1UL; portNVIC_SYSTICK_CTRL_REG = portNVIC_SYSTICK_CLK_BIT_CONFIG | portNVIC_SYSTICK_INT_BIT | portNVIC_SYSTICK_ENABLE_BIT; } #endif /* portNVIC_SYSTICK_CLK_BIT_CONFIG */ /* Step the tick to account for any tick periods that elapsed. */ vTaskStepTick( ulCompleteTickPeriods ); /* Exit with interrupts enabled. */ __asm volatile ( "cpsie i" ::: "memory" ); } } #endif /* configUSE_TICKLESS_IDLE */ /*-----------------------------------------------------------*/ __attribute__( ( weak ) ) void vPortSetupTimerInterrupt( void ) /* PRIVILEGED_FUNCTION */ { /* 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 */ /* Stop and reset SysTick. * * QEMU versions older than 7.0.0 contain a bug which causes an error if we * enable SysTick without first selecting a valid clock source. We trigger * the bug if we change clock sources from a clock with a zero clock period * to one with a nonzero clock period and enable Systick at the same time. * So we configure the CLKSOURCE bit here, prior to setting the ENABLE bit. * This workaround avoids the bug in QEMU versions older than 7.0.0. */ portNVIC_SYSTICK_CTRL_REG = portNVIC_SYSTICK_CLK_BIT_CONFIG; 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_CONFIG | portNVIC_SYSTICK_INT_BIT | portNVIC_SYSTICK_ENABLE_BIT; } /*-----------------------------------------------------------*/ static void prvTaskExitError( void ) { volatile uint32_t ulDummy = 0UL; /* 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( ulCriticalNesting == ~0UL ); portDISABLE_INTERRUPTS(); while( ulDummy == 0 ) { /* This file calls prvTaskExitError() after the scheduler has been * started to remove a compiler warning about the function being * defined but never called. ulDummy is used purely to quieten other * warnings about code appearing after this function is called - making * ulDummy volatile makes the compiler think the function could return * and therefore not output an 'unreachable code' warning for code that * appears after it. */ } } /*-----------------------------------------------------------*/ #if ( configENABLE_MPU == 1 ) static uint32_t prvGetMPURegionSizeSetting( uint32_t ulActualSizeInBytes ) { uint32_t ulRegionSize, ulReturnValue = 7UL; /* 256 is the smallest region size, 31 is the largest valid value for * ulReturnValue. */ for( ulRegionSize = 256UL; ulReturnValue < 31UL; ( ulRegionSize <<= 1UL ) ) { if( ulActualSizeInBytes <= ulRegionSize ) { break; } else { ulReturnValue++; } } /* Shift the code by one before returning so it can be written directly * into the the correct bit position of the attribute register. */ return( ulReturnValue << 1UL ); } #endif /* configENABLE_MPU */ /*-----------------------------------------------------------*/ #if ( configENABLE_MPU == 1 ) static void prvSetupMPU( void ) /* PRIVILEGED_FUNCTION */ { #if defined( __ARMCC_VERSION ) /* Declaration when these variable are defined in code instead of being * exported from linker scripts. */ extern uint32_t * __privileged_functions_start__; extern uint32_t * __privileged_functions_end__; extern uint32_t * __FLASH_segment_start__; extern uint32_t * __FLASH_segment_end__; extern uint32_t * __privileged_sram_start__; extern uint32_t * __privileged_sram_end__; #else /* if defined( __ARMCC_VERSION ) */ /* Declaration when these variable are exported from linker scripts. */ extern uint32_t __privileged_functions_start__[]; extern uint32_t __privileged_functions_end__[]; extern uint32_t __FLASH_segment_start__[]; extern uint32_t __FLASH_segment_end__[]; extern uint32_t __privileged_sram_start__[]; extern uint32_t __privileged_sram_end__[]; #endif /* defined( __ARMCC_VERSION ) */ /* Ensure that the MPU is present. */ configASSERT( portMPU_TYPE_REG == portEXPECTED_MPU_TYPE_VALUE ); /* Check that the MPU is present. */ if( portMPU_TYPE_REG == portEXPECTED_MPU_TYPE_VALUE ) { /* Setup privileged flash as Read Only so that privileged tasks can * read it but not modify. */ portMPU_RBAR_REG = ( ( ( uint32_t ) __privileged_functions_start__ ) | /* Base address. */ ( portMPU_RBAR_REGION_NUMBER_VALID_BITMASK ) | ( portPRIVILEGED_FLASH_REGION ) ); portMPU_RASR_REG = ( ( portMPU_REGION_PRIV_RO_UNPRIV_NA ) | ( ( configS_C_B_FLASH & portMPU_RASR_S_C_B_BITMASK ) << portMPU_RASR_S_C_B_LOCATION ) | ( prvGetMPURegionSizeSetting( ( uint32_t ) __privileged_functions_end__ - ( uint32_t ) __privileged_functions_start__ ) ) | ( portMPU_RASR_REGION_ENABLE_BITMASK ) ); /* Setup unprivileged flash as Read Only by both privileged and * unprivileged tasks. All tasks can read it but no-one can modify. */ portMPU_RBAR_REG = ( ( ( uint32_t ) __FLASH_segment_start__ ) | /* Base address. */ ( portMPU_RBAR_REGION_NUMBER_VALID_BITMASK ) | ( portUNPRIVILEGED_FLASH_REGION ) ); portMPU_RASR_REG = ( ( portMPU_REGION_PRIV_RO_UNPRIV_RO ) | ( ( configS_C_B_FLASH & portMPU_RASR_S_C_B_BITMASK ) << portMPU_RASR_S_C_B_LOCATION ) | ( prvGetMPURegionSizeSetting( ( uint32_t ) __FLASH_segment_end__ - ( uint32_t ) __FLASH_segment_start__ ) ) | ( portMPU_RASR_REGION_ENABLE_BITMASK ) ); /* Setup RAM containing kernel data for privileged access only. */ portMPU_RBAR_REG = ( ( uint32_t ) __privileged_sram_start__ ) | /* Base address. */ ( portMPU_RBAR_REGION_NUMBER_VALID_BITMASK ) | ( portPRIVILEGED_RAM_REGION ); portMPU_RASR_REG = ( ( portMPU_REGION_PRIV_RW_UNPRIV_NA ) | ( portMPU_REGION_EXECUTE_NEVER ) | ( ( configS_C_B_SRAM & portMPU_RASR_S_C_B_BITMASK ) << portMPU_RASR_S_C_B_LOCATION ) | prvGetMPURegionSizeSetting( ( uint32_t ) __privileged_sram_end__ - ( uint32_t ) __privileged_sram_start__ ) | ( portMPU_RASR_REGION_ENABLE_BITMASK ) ); /* Enable MPU with privileged background access i.e. unmapped * regions have privileged access. */ portMPU_CTRL_REG |= ( portMPU_CTRL_PRIV_BACKGROUND_ENABLE_BITMASK | portMPU_CTRL_ENABLE_BITMASK ); } } #endif /* configENABLE_MPU */ /*-----------------------------------------------------------*/ void vPortYield( void ) /* PRIVILEGED_FUNCTION */ { /* 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. */ __asm volatile ( "dsb" ::: "memory" ); __asm volatile ( "isb" ); } /*-----------------------------------------------------------*/ void vPortEnterCritical( void ) /* PRIVILEGED_FUNCTION */ { portDISABLE_INTERRUPTS(); ulCriticalNesting++; /* Barriers are normally not required but do ensure the code is * completely within the specified behaviour for the architecture. */ __asm volatile ( "dsb" ::: "memory" ); __asm volatile ( "isb" ); } /*-----------------------------------------------------------*/ void vPortExitCritical( void ) /* PRIVILEGED_FUNCTION */ { configASSERT( ulCriticalNesting ); ulCriticalNesting--; if( ulCriticalNesting == 0 ) { portENABLE_INTERRUPTS(); } } /*-----------------------------------------------------------*/ void SysTick_Handler( void ) /* PRIVILEGED_FUNCTION */ { uint32_t ulPreviousMask; ulPreviousMask = portSET_INTERRUPT_MASK_FROM_ISR(); traceISR_ENTER(); { /* Increment the RTOS tick. */ if( xTaskIncrementTick() != pdFALSE ) { traceISR_EXIT_TO_SCHEDULER(); /* Pend a context switch. */ portNVIC_INT_CTRL_REG = portNVIC_PENDSVSET_BIT; } else { traceISR_EXIT(); } } portCLEAR_INTERRUPT_MASK_FROM_ISR( ulPreviousMask ); } /*-----------------------------------------------------------*/ void vPortSVCHandler_C( uint32_t * pulCallerStackAddress ) /* PRIVILEGED_FUNCTION portDONT_DISCARD */ { #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 1 ) ) #if defined( __ARMCC_VERSION ) /* Declaration when these variable are defined in code instead of being * exported from linker scripts. */ extern uint32_t * __syscalls_flash_start__; extern uint32_t * __syscalls_flash_end__; #else /* Declaration when these variable are exported from linker scripts. */ extern uint32_t __syscalls_flash_start__[]; extern uint32_t __syscalls_flash_end__[]; #endif /* defined( __ARMCC_VERSION ) */ #endif /* ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 1 ) */ uint32_t ulPC; uint8_t ucSVCNumber; /* Register are stored on the stack in the following order - R0, R1, R2, R3, * R12, LR, PC, xPSR. */ ulPC = pulCallerStackAddress[ portOFFSET_TO_PC ]; ucSVCNumber = ( ( uint8_t * ) ulPC )[ -2 ]; switch( ucSVCNumber ) { case portSVC_START_SCHEDULER: /* Setup the context of the first task so that the first task starts * executing. */ vRestoreContextOfFirstTask(); break; #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 1 ) ) case portSVC_RAISE_PRIVILEGE: /* Only raise the privilege, if the svc was raised from any of * the system calls. */ if( ( ulPC >= ( uint32_t ) __syscalls_flash_start__ ) && ( ulPC <= ( uint32_t ) __syscalls_flash_end__ ) ) { vRaisePrivilege(); } break; #endif /* ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 1 ) */ #if ( configENABLE_MPU == 1 ) case portSVC_YIELD: vPortYield(); break; #endif /* configENABLE_MPU == 1 */ default: /* Incorrect SVC call. */ configASSERT( pdFALSE ); } } /*-----------------------------------------------------------*/ #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) void vSystemCallEnter( uint32_t * pulTaskStack, uint32_t ulLR, uint8_t ucSystemCallNumber ) /* PRIVILEGED_FUNCTION */ { extern TaskHandle_t pxCurrentTCB; extern UBaseType_t uxSystemCallImplementations[ NUM_SYSTEM_CALLS ]; xMPU_SETTINGS * pxMpuSettings; uint32_t * pulSystemCallStack; uint32_t ulSystemCallLocation, i; const uint32_t ulStackFrameSize = 8; #if defined( __ARMCC_VERSION ) /* Declaration when these variable are defined in code instead of being * exported from linker scripts. */ extern uint32_t * __syscalls_flash_start__; extern uint32_t * __syscalls_flash_end__; #else /* Declaration when these variable are exported from linker scripts. */ extern uint32_t __syscalls_flash_start__[]; extern uint32_t __syscalls_flash_end__[]; #endif /* #if defined( __ARMCC_VERSION ) */ ulSystemCallLocation = pulTaskStack[ portOFFSET_TO_PC ]; pxMpuSettings = xTaskGetMPUSettings( pxCurrentTCB ); /* Checks: * 1. SVC is raised from the system call section (i.e. application is * not raising SVC directly). * 2. pxMpuSettings->xSystemCallStackInfo.pulTaskStack must be NULL as * it is non-NULL only during the execution of a system call (i.e. * between system call enter and exit). * 3. System call is not for a kernel API disabled by the configuration * in FreeRTOSConfig.h. * 4. We do not need to check that ucSystemCallNumber is within range * because the assembly SVC handler checks that before calling * this function. */ if( ( ulSystemCallLocation >= ( uint32_t ) __syscalls_flash_start__ ) && ( ulSystemCallLocation <= ( uint32_t ) __syscalls_flash_end__ ) && ( pxMpuSettings->xSystemCallStackInfo.pulTaskStack == NULL ) && ( uxSystemCallImplementations[ ucSystemCallNumber ] != ( UBaseType_t ) 0 ) ) { pulSystemCallStack = pxMpuSettings->xSystemCallStackInfo.pulSystemCallStack; /* Make space on the system call stack for the stack frame. */ pulSystemCallStack = pulSystemCallStack - ulStackFrameSize; /* Copy the stack frame. */ for( i = 0; i < ulStackFrameSize; i++ ) { pulSystemCallStack[ i ] = pulTaskStack[ i ]; } /* Store the value of the Link Register before the SVC was raised. * It contains the address of the caller of the System Call entry * point (i.e. the caller of the MPU_). We need to restore it * when we exit from the system call. */ pxMpuSettings->xSystemCallStackInfo.ulLinkRegisterAtSystemCallEntry = pulTaskStack[ portOFFSET_TO_LR ]; /* Use the pulSystemCallStack in thread mode. */ __asm volatile ( "msr psp, %0" : : "r" ( pulSystemCallStack ) ); /* Start executing the system call upon returning from this handler. */ pulSystemCallStack[ portOFFSET_TO_PC ] = uxSystemCallImplementations[ ucSystemCallNumber ]; /* Raise a request to exit from the system call upon finishing the * system call. */ pulSystemCallStack[ portOFFSET_TO_LR ] = ( uint32_t ) vRequestSystemCallExit; /* Remember the location where we should copy the stack frame when we exit from * the system call. */ pxMpuSettings->xSystemCallStackInfo.pulTaskStack = pulTaskStack + ulStackFrameSize; /* Record if the hardware used padding to force the stack pointer * to be double word aligned. */ if( ( pulTaskStack[ portOFFSET_TO_PSR ] & portPSR_STACK_PADDING_MASK ) == portPSR_STACK_PADDING_MASK ) { pxMpuSettings->ulTaskFlags |= portSTACK_FRAME_HAS_PADDING_FLAG; } else { pxMpuSettings->ulTaskFlags &= ( ~portSTACK_FRAME_HAS_PADDING_FLAG ); } /* We ensure in pxPortInitialiseStack that the system call stack is * double word aligned and therefore, there is no need of padding. * Clear the bit[9] of stacked xPSR. */ pulSystemCallStack[ portOFFSET_TO_PSR ] &= ( ~portPSR_STACK_PADDING_MASK ); /* Raise the privilege for the duration of the system call. */ __asm volatile ( " .syntax unified \n" " mrs r0, control \n" /* Obtain current control value. */ " movs r1, #1 \n" /* r1 = 1. */ " bics r0, r1 \n" /* Clear nPRIV bit. */ " msr control, r0 \n" /* Write back new control value. */ ::: "r0", "r1", "memory" ); } } #endif /* ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) */ /*-----------------------------------------------------------*/ #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) void vRequestSystemCallExit( void ) /* __attribute__( ( naked ) ) PRIVILEGED_FUNCTION */ { __asm volatile ( "svc %0 \n" ::"i" ( portSVC_SYSTEM_CALL_EXIT ) : "memory" ); } #endif /* ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) */ /*-----------------------------------------------------------*/ #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) void vSystemCallExit( uint32_t * pulSystemCallStack, uint32_t ulLR ) /* PRIVILEGED_FUNCTION */ { extern TaskHandle_t pxCurrentTCB; xMPU_SETTINGS * pxMpuSettings; uint32_t * pulTaskStack; uint32_t ulSystemCallLocation, i; const uint32_t ulStackFrameSize = 8; #if defined( __ARMCC_VERSION ) /* Declaration when these variable are defined in code instead of being * exported from linker scripts. */ extern uint32_t * __privileged_functions_start__; extern uint32_t * __privileged_functions_end__; #else /* Declaration when these variable are exported from linker scripts. */ extern uint32_t __privileged_functions_start__[]; extern uint32_t __privileged_functions_end__[]; #endif /* #if defined( __ARMCC_VERSION ) */ ulSystemCallLocation = pulSystemCallStack[ portOFFSET_TO_PC ]; pxMpuSettings = xTaskGetMPUSettings( pxCurrentTCB ); /* Checks: * 1. SVC is raised from the privileged code (i.e. application is not * raising SVC directly). This SVC is only raised from * vRequestSystemCallExit which is in the privileged code section. * 2. pxMpuSettings->xSystemCallStackInfo.pulTaskStack must not be NULL - * this means that we previously entered a system call and the * application is not attempting to exit without entering a system * call. */ if( ( ulSystemCallLocation >= ( uint32_t ) __privileged_functions_start__ ) && ( ulSystemCallLocation <= ( uint32_t ) __privileged_functions_end__ ) && ( pxMpuSettings->xSystemCallStackInfo.pulTaskStack != NULL ) ) { pulTaskStack = pxMpuSettings->xSystemCallStackInfo.pulTaskStack; /* Make space on the task stack for the stack frame. */ pulTaskStack = pulTaskStack - ulStackFrameSize; /* Copy the stack frame. */ for( i = 0; i < ulStackFrameSize; i++ ) { pulTaskStack[ i ] = pulSystemCallStack[ i ]; } /* Use the pulTaskStack in thread mode. */ __asm volatile ( "msr psp, %0" : : "r" ( pulTaskStack ) ); /* Return to the caller of the System Call entry point (i.e. the * caller of the MPU_). */ pulTaskStack[ portOFFSET_TO_PC ] = pxMpuSettings->xSystemCallStackInfo.ulLinkRegisterAtSystemCallEntry; /* Ensure that LR has a valid value.*/ pulTaskStack[ portOFFSET_TO_LR ] = pxMpuSettings->xSystemCallStackInfo.ulLinkRegisterAtSystemCallEntry; /* If the hardware used padding to force the stack pointer * to be double word aligned, set the stacked xPSR bit[9], * otherwise clear it. */ if( ( pxMpuSettings->ulTaskFlags & portSTACK_FRAME_HAS_PADDING_FLAG ) == portSTACK_FRAME_HAS_PADDING_FLAG ) { pulTaskStack[ portOFFSET_TO_PSR ] |= portPSR_STACK_PADDING_MASK; } else { pulTaskStack[ portOFFSET_TO_PSR ] &= ( ~portPSR_STACK_PADDING_MASK ); } /* This is not NULL only for the duration of the system call. */ pxMpuSettings->xSystemCallStackInfo.pulTaskStack = NULL; /* Drop the privilege before returning to the thread mode. */ __asm volatile ( " .syntax unified \n" " mrs r0, control \n" /* Obtain current control value. */ " movs r1, #1 \n" /* r1 = 1. */ " orrs r0, r1 \n" /* Set nPRIV bit. */ " msr control, r0 \n" /* Write back new control value. */ ::: "r0", "r1", "memory" ); } } #endif /* ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) */ /*-----------------------------------------------------------*/ #if ( configENABLE_MPU == 1 ) BaseType_t xPortIsTaskPrivileged( void ) /* PRIVILEGED_FUNCTION */ { BaseType_t xTaskIsPrivileged = pdFALSE; const xMPU_SETTINGS * xTaskMpuSettings = xTaskGetMPUSettings( NULL ); /* Calling task's MPU settings. */ if( ( xTaskMpuSettings->ulTaskFlags & portTASK_IS_PRIVILEGED_FLAG ) == portTASK_IS_PRIVILEGED_FLAG ) { xTaskIsPrivileged = pdTRUE; } return xTaskIsPrivileged; } #endif /* configENABLE_MPU == 1 */ /*-----------------------------------------------------------*/ #if ( configENABLE_MPU == 1 ) StackType_t * pxPortInitialiseStack( StackType_t * pxTopOfStack, TaskFunction_t pxCode, void * pvParameters, BaseType_t xRunPrivileged, xMPU_SETTINGS * xMPUSettings ) /* PRIVILEGED_FUNCTION */ { xMPUSettings->ulContext[ 0 ] = 0x04040404; /* r4. */ xMPUSettings->ulContext[ 1 ] = 0x05050505; /* r5. */ xMPUSettings->ulContext[ 2 ] = 0x06060606; /* r6. */ xMPUSettings->ulContext[ 3 ] = 0x07070707; /* r7. */ xMPUSettings->ulContext[ 4 ] = 0x08080808; /* r8. */ xMPUSettings->ulContext[ 5 ] = 0x09090909; /* r9. */ xMPUSettings->ulContext[ 6 ] = 0x10101010; /* r10. */ xMPUSettings->ulContext[ 7 ] = 0x11111111; /* r11. */ xMPUSettings->ulContext[ 8 ] = ( uint32_t ) pvParameters; /* r0. */ xMPUSettings->ulContext[ 9 ] = 0x01010101; /* r1. */ xMPUSettings->ulContext[ 10 ] = 0x02020202; /* r2. */ xMPUSettings->ulContext[ 11 ] = 0x03030303; /* r3. */ xMPUSettings->ulContext[ 12 ] = 0x12121212; /* r12. */ xMPUSettings->ulContext[ 13 ] = ( uint32_t ) portTASK_RETURN_ADDRESS; /* LR. */ xMPUSettings->ulContext[ 14 ] = ( uint32_t ) pxCode; /* PC. */ xMPUSettings->ulContext[ 15 ] = portINITIAL_XPSR; /* xPSR. */ xMPUSettings->ulContext[ 16 ] = ( uint32_t ) ( pxTopOfStack - 8 ); /* PSP with the hardware saved stack. */ if( xRunPrivileged == pdTRUE ) { xMPUSettings->ulTaskFlags |= portTASK_IS_PRIVILEGED_FLAG; xMPUSettings->ulContext[ 17 ] = ( uint32_t ) portINITIAL_CONTROL_PRIVILEGED; /* CONTROL. */ } else { xMPUSettings->ulTaskFlags &= ( ~portTASK_IS_PRIVILEGED_FLAG ); xMPUSettings->ulContext[ 17 ] = ( uint32_t ) portINITIAL_CONTROL_UNPRIVILEGED; /* CONTROL. */ } xMPUSettings->ulContext[ 18 ] = portINITIAL_EXC_RETURN; /* LR (EXC_RETURN). */ #if ( configUSE_MPU_WRAPPERS_V1 == 0 ) { /* Ensure that the system call stack is double word aligned. */ xMPUSettings->xSystemCallStackInfo.pulSystemCallStack = &( xMPUSettings->xSystemCallStackInfo.ulSystemCallStackBuffer[ configSYSTEM_CALL_STACK_SIZE - 1 ] ); xMPUSettings->xSystemCallStackInfo.pulSystemCallStack = ( uint32_t * ) ( ( uint32_t ) ( xMPUSettings->xSystemCallStackInfo.pulSystemCallStack ) & ( uint32_t ) ( ~( portBYTE_ALIGNMENT_MASK ) ) ); /* This is not NULL only for the duration of a system call. */ xMPUSettings->xSystemCallStackInfo.pulTaskStack = NULL; } #endif /* configUSE_MPU_WRAPPERS_V1 == 0 */ return &( xMPUSettings->ulContext[ 19 ] ); } #else /* configENABLE_MPU */ StackType_t * pxPortInitialiseStack( StackType_t * pxTopOfStack, TaskFunction_t pxCode, void * pvParameters ) /* PRIVILEGED_FUNCTION */ { /* Simulate the stack frame as it would be created by a context switch * interrupt. */ #if ( portPRELOAD_REGISTERS == 0 ) { pxTopOfStack--; /* Offset added to account for the way the MCU uses the stack on entry/exit of interrupts. */ *pxTopOfStack = portINITIAL_XPSR; /* xPSR. */ pxTopOfStack--; *pxTopOfStack = ( StackType_t ) pxCode; /* PC. */ pxTopOfStack--; *pxTopOfStack = ( StackType_t ) portTASK_RETURN_ADDRESS; /* LR. */ pxTopOfStack -= 5; /* R12, R3, R2 and R1. */ *pxTopOfStack = ( StackType_t ) pvParameters; /* R0. */ pxTopOfStack -= 9; /* R11..R4, EXC_RETURN. */ *pxTopOfStack = portINITIAL_EXC_RETURN; } #else /* portPRELOAD_REGISTERS */ { pxTopOfStack--; /* Offset added to account for the way the MCU uses the stack on entry/exit of interrupts. */ *pxTopOfStack = portINITIAL_XPSR; /* xPSR. */ pxTopOfStack--; *pxTopOfStack = ( StackType_t ) pxCode; /* PC. */ pxTopOfStack--; *pxTopOfStack = ( StackType_t ) portTASK_RETURN_ADDRESS; /* LR. */ pxTopOfStack--; *pxTopOfStack = ( StackType_t ) 0x12121212UL; /* R12. */ pxTopOfStack--; *pxTopOfStack = ( StackType_t ) 0x03030303UL; /* R3. */ pxTopOfStack--; *pxTopOfStack = ( StackType_t ) 0x02020202UL; /* R2. */ pxTopOfStack--; *pxTopOfStack = ( StackType_t ) 0x01010101UL; /* R1. */ pxTopOfStack--; *pxTopOfStack = ( StackType_t ) pvParameters; /* R0. */ pxTopOfStack--; *pxTopOfStack = ( StackType_t ) 0x11111111UL; /* R11. */ pxTopOfStack--; *pxTopOfStack = ( StackType_t ) 0x10101010UL; /* R10. */ pxTopOfStack--; *pxTopOfStack = ( StackType_t ) 0x09090909UL; /* R09. */ pxTopOfStack--; *pxTopOfStack = ( StackType_t ) 0x08080808UL; /* R08. */ pxTopOfStack--; *pxTopOfStack = ( StackType_t ) 0x07070707UL; /* R07. */ pxTopOfStack--; *pxTopOfStack = ( StackType_t ) 0x06060606UL; /* R06. */ pxTopOfStack--; *pxTopOfStack = ( StackType_t ) 0x05050505UL; /* R05. */ pxTopOfStack--; *pxTopOfStack = ( StackType_t ) 0x04040404UL; /* R04. */ pxTopOfStack--; *pxTopOfStack = portINITIAL_EXC_RETURN; /* EXC_RETURN. */ } #endif /* portPRELOAD_REGISTERS */ return pxTopOfStack; } #endif /* configENABLE_MPU */ /*-----------------------------------------------------------*/ BaseType_t xPortStartScheduler( void ) /* PRIVILEGED_FUNCTION */ { /* An application can install FreeRTOS interrupt handlers in one of the * following ways: * 1. Direct Routing - Install the functions SVC_Handler and PendSV_Handler * for SVCall and PendSV interrupts respectively. * 2. Indirect Routing - Install separate handlers for SVCall and PendSV * interrupts and route program control from those handlers to * SVC_Handler and PendSV_Handler functions. * * Applications that use Indirect Routing must set * configCHECK_HANDLER_INSTALLATION to 0 in their FreeRTOSConfig.h. Direct * routing, which is validated here when configCHECK_HANDLER_INSTALLATION * is 1, should be preferred when possible. */ #if ( configCHECK_HANDLER_INSTALLATION == 1 ) { const portISR_t * const pxVectorTable = portSCB_VTOR_REG; /* Validate that the application has correctly installed the FreeRTOS * handlers for SVCall and PendSV interrupts. We do not check the * installation of the SysTick handler because the application may * choose to drive the RTOS tick using a timer other than the SysTick * timer by overriding the weak function vPortSetupTimerInterrupt(). * * Assertion failures here indicate incorrect installation of the * FreeRTOS handlers. For help installing the FreeRTOS handlers, see * https://www.FreeRTOS.org/FAQHelp.html. * * Systems with a configurable address for the interrupt vector table * can also encounter assertion failures or even system faults here if * VTOR is not set correctly to point to the application's vector table. */ configASSERT( pxVectorTable[ portVECTOR_INDEX_SVC ] == SVC_Handler ); configASSERT( pxVectorTable[ portVECTOR_INDEX_PENDSV ] == PendSV_Handler ); } #endif /* configCHECK_HANDLER_INSTALLATION */ /* Make PendSV and SysTick the lowest priority interrupts, and make SVCall * the highest priority. */ portNVIC_SHPR3_REG |= portNVIC_PENDSV_PRI; portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI; portNVIC_SHPR2_REG = 0; #if ( configENABLE_MPU == 1 ) { /* Setup the Memory Protection Unit (MPU). */ prvSetupMPU(); } #endif /* configENABLE_MPU */ /* Start the timer that generates the tick ISR. Interrupts are disabled * here already. */ vPortSetupTimerInterrupt(); /* Initialize the critical nesting count ready for the first task. */ ulCriticalNesting = 0; #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) { xSchedulerRunning = pdTRUE; } #endif /* Start the first task. */ vStartFirstTask(); /* Should never get here as the tasks will now be executing. Call the task * exit error function to prevent compiler warnings about a static function * not being called in the case that the application writer overrides this * functionality by defining configTASK_RETURN_ADDRESS. Call * vTaskSwitchContext() so link time optimization does not remove the * symbol. */ vTaskSwitchContext(); prvTaskExitError(); /* Should not get here. */ return 0; } /*-----------------------------------------------------------*/ void vPortEndScheduler( void ) /* PRIVILEGED_FUNCTION */ { /* Not implemented in ports where there is nothing to return to. * Artificially force an assert. */ configASSERT( ulCriticalNesting == 1000UL ); } /*-----------------------------------------------------------*/ #if ( configENABLE_MPU == 1 ) void vPortStoreTaskMPUSettings( xMPU_SETTINGS * xMPUSettings, const struct xMEMORY_REGION * const xRegions, StackType_t * pxBottomOfStack, configSTACK_DEPTH_TYPE uxStackDepth ) { #if defined( __ARMCC_VERSION ) /* Declaration when these variable are defined in code instead of being * exported from linker scripts. */ extern uint32_t * __SRAM_segment_start__; extern uint32_t * __SRAM_segment_end__; extern uint32_t * __privileged_sram_start__; extern uint32_t * __privileged_sram_end__; #else /* Declaration when these variable are exported from linker scripts. */ extern uint32_t __SRAM_segment_start__[]; extern uint32_t __SRAM_segment_end__[]; extern uint32_t __privileged_sram_start__[]; extern uint32_t __privileged_sram_end__[]; #endif /* defined( __ARMCC_VERSION ) */ int32_t lIndex; uint32_t ul; if( xRegions == NULL ) { /* No MPU regions are specified so allow access to all RAM. */ xMPUSettings->xRegionsSettings[ 0 ].ulRBAR = ( ( ( uint32_t ) __SRAM_segment_start__ ) | /* Base address. */ ( portMPU_RBAR_REGION_NUMBER_VALID_BITMASK ) | ( portSTACK_REGION ) ); /* Region number. */ xMPUSettings->xRegionsSettings[ 0 ].ulRASR = ( ( portMPU_REGION_PRIV_RW_UNPRIV_RW ) | ( portMPU_REGION_EXECUTE_NEVER ) | ( ( configS_C_B_SRAM & portMPU_RASR_S_C_B_BITMASK ) << portMPU_RASR_S_C_B_LOCATION ) | ( prvGetMPURegionSizeSetting( ( uint32_t ) __SRAM_segment_end__ - ( uint32_t ) __SRAM_segment_start__ ) ) | ( portMPU_RASR_REGION_ENABLE_BITMASK ) ); /* Invalidate user configurable regions. */ for( ul = 1UL; ul <= portNUM_CONFIGURABLE_REGIONS; ul++ ) { xMPUSettings->xRegionsSettings[ ul ].ulRBAR = ( ( ul - 1UL ) | portMPU_RBAR_REGION_NUMBER_VALID_BITMASK ); xMPUSettings->xRegionsSettings[ ul ].ulRASR = 0UL; } } else { /* This function is called automatically when the task is created - in * which case the stack region parameters will be valid. At all other * times the stack parameters will not be valid and it is assumed that the * stack region has already been configured. */ if( uxStackDepth > 0 ) { /* Define the region that allows access to the stack. */ xMPUSettings->xRegionsSettings[ 0 ].ulRBAR = ( ( ( uint32_t ) pxBottomOfStack ) | ( portMPU_RBAR_REGION_NUMBER_VALID_BITMASK ) | ( portSTACK_REGION ) ); /* Region number. */ xMPUSettings->xRegionsSettings[ 0 ].ulRASR = ( ( portMPU_REGION_PRIV_RW_UNPRIV_RW ) | ( portMPU_REGION_EXECUTE_NEVER ) | ( prvGetMPURegionSizeSetting( uxStackDepth * ( uint32_t ) sizeof( StackType_t ) ) ) | ( ( configS_C_B_SRAM & portMPU_RASR_S_C_B_BITMASK ) << portMPU_RASR_S_C_B_LOCATION ) | ( portMPU_RASR_REGION_ENABLE_BITMASK ) ); } lIndex = 0; for( ul = 1UL; ul <= portNUM_CONFIGURABLE_REGIONS; ul++ ) { if( ( xRegions[ lIndex ] ).ulLengthInBytes > 0UL ) { /* Translate the generic region definition contained in * xRegions into the CM0+ specific MPU settings that are then * stored in xMPUSettings. */ xMPUSettings->xRegionsSettings[ ul ].ulRBAR = ( ( uint32_t ) xRegions[ lIndex ].pvBaseAddress ) | ( portMPU_RBAR_REGION_NUMBER_VALID_BITMASK ) | ( ul - 1UL ); /* Region number. */ xMPUSettings->xRegionsSettings[ ul ].ulRASR = ( prvGetMPURegionSizeSetting( xRegions[ lIndex ].ulLengthInBytes ) ) | ( xRegions[ lIndex ].ulParameters ) | ( portMPU_RASR_REGION_ENABLE_BITMASK ); } else { /* Invalidate the region. */ xMPUSettings->xRegionsSettings[ ul ].ulRBAR = ( ( ul - 1UL ) | portMPU_RBAR_REGION_NUMBER_VALID_BITMASK ); xMPUSettings->xRegionsSettings[ ul ].ulRASR = 0UL; } lIndex++; } } } #endif /* configENABLE_MPU */ /*-----------------------------------------------------------*/ #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) BaseType_t xPortIsAuthorizedToAccessBuffer( const void * pvBuffer, uint32_t ulBufferLength, uint32_t ulAccessRequested ) /* PRIVILEGED_FUNCTION */ { uint32_t i, ulBufferStartAddress, ulBufferEndAddress; uint32_t ulRegionStart, ulRegionSize, ulRegionEnd; uint32_t ulMPURegionAccessPermissions; BaseType_t xAccessGranted = pdFALSE; const xMPU_SETTINGS * xTaskMpuSettings = xTaskGetMPUSettings( NULL ); /* Calling task's MPU settings. */ if( xSchedulerRunning == pdFALSE ) { /* Grant access to all the kernel objects before the scheduler * is started. It is necessary because there is no task running * yet and therefore, we cannot use the permissions of any * task. */ xAccessGranted = pdTRUE; } else if( ( xTaskMpuSettings->ulTaskFlags & portTASK_IS_PRIVILEGED_FLAG ) == portTASK_IS_PRIVILEGED_FLAG ) { xAccessGranted = pdTRUE; } else { if( portADD_UINT32_WILL_OVERFLOW( ( ( uint32_t ) pvBuffer ), ( ulBufferLength - 1UL ) ) == pdFALSE ) { ulBufferStartAddress = ( uint32_t ) pvBuffer; ulBufferEndAddress = ( ( ( uint32_t ) pvBuffer ) + ulBufferLength - 1UL ); for( i = 0; i < portTOTAL_NUM_REGIONS; i++ ) { /* Is the MPU region enabled? */ if( ( xTaskMpuSettings->xRegionsSettings[ i ].ulRASR & portMPU_RASR_REGION_ENABLE_BITMASK ) == portMPU_RASR_REGION_ENABLE_BITMASK ) { ulRegionStart = portEXTRACT_FIRST_ADDRESS_FROM_RBAR( xTaskMpuSettings->xRegionsSettings[ i ].ulRBAR ); ulRegionSize = portEXTRACT_REGION_SIZE_FROM_RASR( xTaskMpuSettings->xRegionsSettings[ i ].ulRASR ); ulRegionEnd = ulRegionStart + ulRegionSize; if( portIS_ADDRESS_WITHIN_RANGE( ulBufferStartAddress, ulRegionStart, ulRegionEnd ) && portIS_ADDRESS_WITHIN_RANGE( ulBufferEndAddress, ulRegionStart, ulRegionEnd ) ) { ulMPURegionAccessPermissions = xTaskMpuSettings->xRegionsSettings[ i ].ulRASR & portMPU_RASR_AP_BITMASK; if( ulAccessRequested == tskMPU_READ_PERMISSION ) /* RO. */ { if( ( ulMPURegionAccessPermissions == portMPU_REGION_PRIV_RW_UNPRIV_RO ) || ( ulMPURegionAccessPermissions == portMPU_REGION_PRIV_RO_UNPRIV_RO ) || ( ulMPURegionAccessPermissions == portMPU_REGION_PRIV_RW_UNPRIV_RW ) ) { xAccessGranted = pdTRUE; break; } } else if( ( ulAccessRequested & tskMPU_WRITE_PERMISSION ) != 0UL ) /* W or RW. */ { if( ulMPURegionAccessPermissions == portMPU_REGION_PRIV_RW_UNPRIV_RW ) { xAccessGranted = pdTRUE; break; } } } } } } } return xAccessGranted; } #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */ /*-----------------------------------------------------------*/ BaseType_t xPortIsInsideInterrupt( void ) { uint32_t ulCurrentInterrupt; BaseType_t xReturn; /* Obtain the number of the currently executing interrupt. Interrupt Program * Status Register (IPSR) holds the exception number of the currently-executing * exception or zero for Thread mode.*/ __asm volatile ( "mrs %0, ipsr" : "=r" ( ulCurrentInterrupt )::"memory" ); if( ulCurrentInterrupt == 0 ) { xReturn = pdFALSE; } else { xReturn = pdTRUE; } return xReturn; } /*-----------------------------------------------------------*/ #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) && ( configENABLE_ACCESS_CONTROL_LIST == 1 ) ) void vPortGrantAccessToKernelObject( TaskHandle_t xInternalTaskHandle, int32_t lInternalIndexOfKernelObject ) /* PRIVILEGED_FUNCTION */ { uint32_t ulAccessControlListEntryIndex, ulAccessControlListEntryBit; xMPU_SETTINGS * xTaskMpuSettings; ulAccessControlListEntryIndex = ( ( uint32_t ) lInternalIndexOfKernelObject / portACL_ENTRY_SIZE_BITS ); ulAccessControlListEntryBit = ( ( uint32_t ) lInternalIndexOfKernelObject % portACL_ENTRY_SIZE_BITS ); xTaskMpuSettings = xTaskGetMPUSettings( xInternalTaskHandle ); xTaskMpuSettings->ulAccessControlList[ ulAccessControlListEntryIndex ] |= ( 1U << ulAccessControlListEntryBit ); } #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) && ( configENABLE_ACCESS_CONTROL_LIST == 1 ) ) */ /*-----------------------------------------------------------*/ #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) && ( configENABLE_ACCESS_CONTROL_LIST == 1 ) ) void vPortRevokeAccessToKernelObject( TaskHandle_t xInternalTaskHandle, int32_t lInternalIndexOfKernelObject ) /* PRIVILEGED_FUNCTION */ { uint32_t ulAccessControlListEntryIndex, ulAccessControlListEntryBit; xMPU_SETTINGS * xTaskMpuSettings; ulAccessControlListEntryIndex = ( ( uint32_t ) lInternalIndexOfKernelObject / portACL_ENTRY_SIZE_BITS ); ulAccessControlListEntryBit = ( ( uint32_t ) lInternalIndexOfKernelObject % portACL_ENTRY_SIZE_BITS ); xTaskMpuSettings = xTaskGetMPUSettings( xInternalTaskHandle ); xTaskMpuSettings->ulAccessControlList[ ulAccessControlListEntryIndex ] &= ~( 1U << ulAccessControlListEntryBit ); } #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) && ( configENABLE_ACCESS_CONTROL_LIST == 1 ) ) */ /*-----------------------------------------------------------*/ #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) #if ( configENABLE_ACCESS_CONTROL_LIST == 1 ) BaseType_t xPortIsAuthorizedToAccessKernelObject( int32_t lInternalIndexOfKernelObject ) /* PRIVILEGED_FUNCTION */ { uint32_t ulAccessControlListEntryIndex, ulAccessControlListEntryBit; BaseType_t xAccessGranted = pdFALSE; const xMPU_SETTINGS * xTaskMpuSettings; if( xSchedulerRunning == pdFALSE ) { /* Grant access to all the kernel objects before the scheduler * is started. It is necessary because there is no task running * yet and therefore, we cannot use the permissions of any * task. */ xAccessGranted = pdTRUE; } else { xTaskMpuSettings = xTaskGetMPUSettings( NULL ); /* Calling task's MPU settings. */ ulAccessControlListEntryIndex = ( ( uint32_t ) lInternalIndexOfKernelObject / portACL_ENTRY_SIZE_BITS ); ulAccessControlListEntryBit = ( ( uint32_t ) lInternalIndexOfKernelObject % portACL_ENTRY_SIZE_BITS ); if( ( xTaskMpuSettings->ulTaskFlags & portTASK_IS_PRIVILEGED_FLAG ) == portTASK_IS_PRIVILEGED_FLAG ) { xAccessGranted = pdTRUE; } else { if( ( xTaskMpuSettings->ulAccessControlList[ ulAccessControlListEntryIndex ] & ( 1U << ulAccessControlListEntryBit ) ) != 0 ) { xAccessGranted = pdTRUE; } } } return xAccessGranted; } #else /* #if ( configENABLE_ACCESS_CONTROL_LIST == 1 ) */ BaseType_t xPortIsAuthorizedToAccessKernelObject( int32_t lInternalIndexOfKernelObject ) /* PRIVILEGED_FUNCTION */ { ( void ) lInternalIndexOfKernelObject; /* If Access Control List feature is not used, all the tasks have * access to all the kernel objects. */ return pdTRUE; } #endif /* #if ( configENABLE_ACCESS_CONTROL_LIST == 1 ) */ #endif /* #if ( ( configENABLE_MPU == 1 ) && ( configUSE_MPU_WRAPPERS_V1 == 0 ) ) */ /*-----------------------------------------------------------*/