| /* |
| * FreeRTOS Kernel <DEVELOPMENT BRANCH> |
| * 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 |
| * |
| */ |
| |
| /*----------------------------------------------------------- |
| * Implementation of functions defined in portable.h for the SH2A port. |
| *----------------------------------------------------------*/ |
| |
| /* Standard C includes. */ |
| #include "limits.h" |
| |
| /* Scheduler includes. */ |
| #include "FreeRTOS.h" |
| #include "task.h" |
| |
| /* Library includes. */ |
| #include "string.h" |
| |
| /* Hardware specifics. */ |
| #if ( configINCLUDE_PLATFORM_H_INSTEAD_OF_IODEFINE_H == 1 ) |
| |
| #include "platform.h" |
| |
| #else /* configINCLUDE_PLATFORM_H_INSTEAD_OF_IODEFINE_H */ |
| |
| #include "iodefine.h" |
| |
| #endif /* configINCLUDE_PLATFORM_H_INSTEAD_OF_IODEFINE_H */ |
| /*-----------------------------------------------------------*/ |
| |
| /* Tasks should start with interrupts enabled and in Supervisor mode, therefore |
| * PSW is set with U and I set, and PM and IPL clear. */ |
| #define portINITIAL_PSW ( ( StackType_t ) 0x00030000 ) |
| |
| /* The peripheral clock is divided by this value before being supplying the |
| * CMT. */ |
| #if ( configUSE_TICKLESS_IDLE == 0 ) |
| /* If tickless idle is not used then the divisor can be fixed. */ |
| #define portCLOCK_DIVISOR 8UL |
| #elif ( configPERIPHERAL_CLOCK_HZ >= 12000000 ) |
| #define portCLOCK_DIVISOR 512UL |
| #elif ( configPERIPHERAL_CLOCK_HZ >= 6000000 ) |
| #define portCLOCK_DIVISOR 128UL |
| #elif ( configPERIPHERAL_CLOCK_HZ >= 1000000 ) |
| #define portCLOCK_DIVISOR 32UL |
| #else |
| #define portCLOCK_DIVISOR 8UL |
| #endif |
| |
| /* These macros allow a critical section to be added around the call to |
| * xTaskIncrementTick(), which is only ever called from interrupts at the kernel |
| * priority - ie a known priority. Therefore these local macros are a slight |
| * optimisation compared to calling the global SET/CLEAR_INTERRUPT_MASK macros, |
| * which would require the old IPL to be read first and stored in a local variable. */ |
| #define portDISABLE_INTERRUPTS_FROM_KERNEL_ISR() __asm volatile ( "MVTIPL %0" ::"i" ( configMAX_SYSCALL_INTERRUPT_PRIORITY ) ) |
| #define portENABLE_INTERRUPTS_FROM_KERNEL_ISR() __asm volatile ( "MVTIPL %0" ::"i" ( configKERNEL_INTERRUPT_PRIORITY ) ) |
| |
| /* Keys required to lock and unlock access to certain system registers |
| * respectively. */ |
| #define portUNLOCK_KEY 0xA50B |
| #define portLOCK_KEY 0xA500 |
| |
| /*-----------------------------------------------------------*/ |
| |
| /* |
| * Function to start the first task executing - written in asm code as direct |
| * access to registers is required. |
| */ |
| static void prvStartFirstTask( void ) __attribute__( ( naked ) ); |
| |
| /* |
| * Software interrupt handler. Performs the actual context switch (saving and |
| * restoring of registers). Written in asm code as direct register access is |
| * required. |
| */ |
| #if ( configINCLUDE_PLATFORM_H_INSTEAD_OF_IODEFINE_H == 1 ) |
| |
| R_BSP_PRAGMA_INTERRUPT( vPortSoftwareInterruptISR, VECT( ICU, SWINT ) ) |
| R_BSP_ATTRIB_INTERRUPT void vPortSoftwareInterruptISR( void ) __attribute__( ( naked ) ); |
| |
| #else /* configINCLUDE_PLATFORM_H_INSTEAD_OF_IODEFINE_H */ |
| |
| void vPortSoftwareInterruptISR( void ) __attribute__( ( naked ) ); |
| |
| #endif /* configINCLUDE_PLATFORM_H_INSTEAD_OF_IODEFINE_H */ |
| |
| /* |
| * The tick ISR handler. The peripheral used is configured by the application |
| * via a hook/callback function. |
| */ |
| #if ( configINCLUDE_PLATFORM_H_INSTEAD_OF_IODEFINE_H == 1 ) |
| |
| R_BSP_PRAGMA_INTERRUPT( vPortTickISR, _VECT( configTICK_VECTOR ) ) |
| R_BSP_ATTRIB_INTERRUPT void vPortTickISR( void ); /* Do not add __attribute__( ( interrupt ) ). */ |
| |
| #else /* configINCLUDE_PLATFORM_H_INSTEAD_OF_IODEFINE_H */ |
| |
| void vPortTickISR( void ) __attribute__( ( interrupt ) ); |
| |
| #endif /* configINCLUDE_PLATFORM_H_INSTEAD_OF_IODEFINE_H */ |
| |
| /* |
| * Sets up the periodic ISR used for the RTOS tick using the CMT. |
| * The application writer can define configSETUP_TICK_INTERRUPT() (in |
| * FreeRTOSConfig.h) such that their own tick interrupt configuration is used |
| * in place of prvSetupTimerInterrupt(). |
| */ |
| static void prvSetupTimerInterrupt( void ); |
| #ifndef configSETUP_TICK_INTERRUPT |
| |
| /* The user has not provided their own tick interrupt configuration so use |
| * the definition in this file (which uses the interval timer). */ |
| #define configSETUP_TICK_INTERRUPT() prvSetupTimerInterrupt() |
| #endif /* configSETUP_TICK_INTERRUPT */ |
| |
| /* |
| * Called after the sleep mode registers have been configured, prvSleep() |
| * executes the pre and post sleep macros, and actually calls the wait |
| * instruction. |
| */ |
| #if configUSE_TICKLESS_IDLE == 1 |
| static void prvSleep( TickType_t xExpectedIdleTime ); |
| #endif /* configUSE_TICKLESS_IDLE */ |
| |
| /*-----------------------------------------------------------*/ |
| |
| /* Used in the context save and restore code. */ |
| extern void * pxCurrentTCB; |
| |
| /* Calculate how many clock increments make up a single tick period. */ |
| static const uint32_t ulMatchValueForOneTick = ( ( configPERIPHERAL_CLOCK_HZ / portCLOCK_DIVISOR ) / configTICK_RATE_HZ ); |
| |
| #if configUSE_TICKLESS_IDLE == 1 |
| |
| /* Holds the maximum number of ticks that can be suppressed - which is |
| * basically how far into the future an interrupt can be generated. Set |
| * during initialisation. This is the maximum possible value that the |
| * compare match register can hold divided by ulMatchValueForOneTick. */ |
| static const TickType_t xMaximumPossibleSuppressedTicks = USHRT_MAX / ( ( configPERIPHERAL_CLOCK_HZ / portCLOCK_DIVISOR ) / configTICK_RATE_HZ ); |
| |
| /* Flag set from the tick interrupt to allow the sleep processing to know if |
| * sleep mode was exited because of a tick interrupt, or an interrupt |
| * generated by something else. */ |
| static volatile uint32_t ulTickFlag = pdFALSE; |
| |
| /* The CMT counter is stopped temporarily each time it is re-programmed. |
| * The following constant offsets the CMT counter match value by the number of |
| * CMT counts that would typically be missed while the counter was stopped to |
| * compensate for the lost time. The large difference between the divided CMT |
| * clock and the CPU clock means it is likely ulStoppedTimerCompensation will |
| * equal zero - and be optimised away. */ |
| static const uint32_t ulStoppedTimerCompensation = 100UL / ( configCPU_CLOCK_HZ / ( configPERIPHERAL_CLOCK_HZ / portCLOCK_DIVISOR ) ); |
| |
| #endif /* if configUSE_TICKLESS_IDLE == 1 */ |
| |
| /*-----------------------------------------------------------*/ |
| |
| /* |
| * See header file for description. |
| */ |
| StackType_t * pxPortInitialiseStack( StackType_t * pxTopOfStack, |
| TaskFunction_t pxCode, |
| void * pvParameters ) |
| { |
| /* Offset to end up on 8 byte boundary. */ |
| pxTopOfStack--; |
| |
| /* R0 is not included as it is the stack pointer. */ |
| *pxTopOfStack = 0x00; |
| pxTopOfStack--; |
| *pxTopOfStack = 0x00; |
| pxTopOfStack--; |
| *pxTopOfStack = portINITIAL_PSW; |
| pxTopOfStack--; |
| *pxTopOfStack = ( StackType_t ) pxCode; |
| |
| /* When debugging it can be useful if every register is set to a known |
| * value. Otherwise code space can be saved by just setting the registers |
| * that need to be set. */ |
| #ifdef USE_FULL_REGISTER_INITIALISATION |
| { |
| pxTopOfStack--; |
| *pxTopOfStack = 0x12345678; /* r15. */ |
| pxTopOfStack--; |
| *pxTopOfStack = 0xaaaabbbb; |
| pxTopOfStack--; |
| *pxTopOfStack = 0xdddddddd; |
| pxTopOfStack--; |
| *pxTopOfStack = 0xcccccccc; |
| pxTopOfStack--; |
| *pxTopOfStack = 0xbbbbbbbb; |
| pxTopOfStack--; |
| *pxTopOfStack = 0xaaaaaaaa; |
| pxTopOfStack--; |
| *pxTopOfStack = 0x99999999; |
| pxTopOfStack--; |
| *pxTopOfStack = 0x88888888; |
| pxTopOfStack--; |
| *pxTopOfStack = 0x77777777; |
| pxTopOfStack--; |
| *pxTopOfStack = 0x66666666; |
| pxTopOfStack--; |
| *pxTopOfStack = 0x55555555; |
| pxTopOfStack--; |
| *pxTopOfStack = 0x44444444; |
| pxTopOfStack--; |
| *pxTopOfStack = 0x33333333; |
| pxTopOfStack--; |
| *pxTopOfStack = 0x22222222; |
| pxTopOfStack--; |
| } |
| #else /* ifdef USE_FULL_REGISTER_INITIALISATION */ |
| { |
| /* Leave space for the registers that will get popped from the stack |
| * when the task first starts executing. */ |
| pxTopOfStack -= 15; |
| } |
| #endif /* ifdef USE_FULL_REGISTER_INITIALISATION */ |
| |
| *pxTopOfStack = ( StackType_t ) pvParameters; /* R1 */ |
| pxTopOfStack--; |
| *pxTopOfStack = 0x12345678; /* Accumulator. */ |
| pxTopOfStack--; |
| *pxTopOfStack = 0x87654321; /* Accumulator. */ |
| |
| return pxTopOfStack; |
| } |
| /*-----------------------------------------------------------*/ |
| |
| BaseType_t xPortStartScheduler( void ) |
| { |
| /* Use pxCurrentTCB just so it does not get optimised away. */ |
| if( pxCurrentTCB != NULL ) |
| { |
| /* Call an application function to set up the timer that will generate |
| * the tick interrupt. This way the application can decide which |
| * peripheral to use. If tickless mode is used then the default |
| * implementation defined in this file (which uses CMT0) should not be |
| * overridden. */ |
| configSETUP_TICK_INTERRUPT(); |
| |
| /* Enable the software interrupt. */ |
| _IEN( _ICU_SWINT ) = 1; |
| |
| /* Ensure the software interrupt is clear. */ |
| _IR( _ICU_SWINT ) = 0; |
| |
| /* Ensure the software interrupt is set to the kernel priority. */ |
| _IPR( _ICU_SWINT ) = configKERNEL_INTERRUPT_PRIORITY; |
| |
| /* Start the first task. */ |
| prvStartFirstTask(); |
| } |
| |
| /* Execution should not reach here as the tasks are now running! |
| * prvSetupTimerInterrupt() is called here to prevent the compiler outputting |
| * a warning about a statically declared function not being referenced in the |
| * case that the application writer has provided their own tick interrupt |
| * configuration routine (and defined configSETUP_TICK_INTERRUPT() such that |
| * their own routine will be called in place of prvSetupTimerInterrupt()). */ |
| prvSetupTimerInterrupt(); |
| |
| /* Should not get here. */ |
| return pdFAIL; |
| } |
| /*-----------------------------------------------------------*/ |
| |
| void vPortEndScheduler( void ) |
| { |
| /* Not implemented in ports where there is nothing to return to. |
| * Artificially force an assert. */ |
| configASSERT( pxCurrentTCB == NULL ); |
| } |
| /*-----------------------------------------------------------*/ |
| |
| static void prvStartFirstTask( void ) |
| { |
| __asm volatile |
| ( |
| |
| /* When starting the scheduler there is nothing that needs moving to the |
| * interrupt stack because the function is not called from an interrupt. |
| * Just ensure the current stack is the user stack. */ |
| "SETPSW U \n" \ |
| |
| |
| /* Obtain the location of the stack associated with which ever task |
| * pxCurrentTCB is currently pointing to. */ |
| "MOV.L #_pxCurrentTCB, R15 \n" \ |
| "MOV.L [R15], R15 \n" \ |
| "MOV.L [R15], R0 \n" \ |
| |
| |
| /* Restore the registers from the stack of the task pointed to by |
| * pxCurrentTCB. */ |
| "POP R15 \n" \ |
| |
| /* Accumulator low 32 bits. */ |
| "MVTACLO R15 \n" \ |
| "POP R15 \n" \ |
| |
| /* Accumulator high 32 bits. */ |
| "MVTACHI R15 \n" \ |
| |
| /* R1 to R15 - R0 is not included as it is the SP. */ |
| "POPM R1-R15 \n" \ |
| |
| /* This pops the remaining registers. */ |
| "RTE \n" \ |
| "NOP \n" \ |
| "NOP \n" |
| ); |
| } |
| /*-----------------------------------------------------------*/ |
| |
| void vPortSoftwareInterruptISR( void ) |
| { |
| __asm volatile |
| ( |
| /* Re-enable interrupts. */ |
| "SETPSW I \n" \ |
| |
| |
| /* Move the data that was automatically pushed onto the interrupt stack when |
| * the interrupt occurred from the interrupt stack to the user stack. |
| * |
| * R15 is saved before it is clobbered. */ |
| "PUSH.L R15 \n" \ |
| |
| /* Read the user stack pointer. */ |
| "MVFC USP, R15 \n" \ |
| |
| /* Move the address down to the data being moved. */ |
| "SUB #12, R15 \n" \ |
| "MVTC R15, USP \n" \ |
| |
| /* Copy the data across, R15, then PC, then PSW. */ |
| "MOV.L [ R0 ], [ R15 ] \n" \ |
| "MOV.L 4[ R0 ], 4[ R15 ] \n" \ |
| "MOV.L 8[ R0 ], 8[ R15 ] \n" \ |
| |
| /* Move the interrupt stack pointer to its new correct position. */ |
| "ADD #12, R0 \n" \ |
| |
| /* All the rest of the registers are saved directly to the user stack. */ |
| "SETPSW U \n" \ |
| |
| /* Save the rest of the general registers (R15 has been saved already). */ |
| "PUSHM R1-R14 \n" \ |
| |
| /* Save the accumulator. */ |
| "MVFACHI R15 \n" \ |
| "PUSH.L R15 \n" \ |
| |
| /* Middle word. */ |
| "MVFACMI R15 \n" \ |
| |
| /* Shifted left as it is restored to the low order word. */ |
| "SHLL #16, R15 \n" \ |
| "PUSH.L R15 \n" \ |
| |
| /* Save the stack pointer to the TCB. */ |
| "MOV.L #_pxCurrentTCB, R15 \n" \ |
| "MOV.L [ R15 ], R15 \n" \ |
| "MOV.L R0, [ R15 ] \n" \ |
| |
| |
| /* Ensure the interrupt mask is set to the syscall priority while the kernel |
| * structures are being accessed. */ |
| "MVTIPL %0 \n" \ |
| |
| /* Select the next task to run. */ |
| "BSR.A _vTaskSwitchContext \n" \ |
| |
| /* Reset the interrupt mask as no more data structure access is required. */ |
| "MVTIPL %1 \n" \ |
| |
| |
| /* Load the stack pointer of the task that is now selected as the Running |
| * state task from its TCB. */ |
| "MOV.L #_pxCurrentTCB,R15 \n" \ |
| "MOV.L [ R15 ], R15 \n" \ |
| "MOV.L [ R15 ], R0 \n" \ |
| |
| |
| /* Restore the context of the new task. The PSW (Program Status Word) and |
| * PC will be popped by the RTE instruction. */ |
| "POP R15 \n" \ |
| "MVTACLO R15 \n" \ |
| "POP R15 \n" \ |
| "MVTACHI R15 \n" \ |
| "POPM R1-R15 \n" \ |
| "RTE \n" \ |
| "NOP \n" \ |
| "NOP " |
| ::"i" ( configMAX_SYSCALL_INTERRUPT_PRIORITY ), "i" ( configKERNEL_INTERRUPT_PRIORITY ) |
| ); |
| } |
| /*-----------------------------------------------------------*/ |
| |
| void vPortTickISR( void ) |
| { |
| /* Re-enabled interrupts. */ |
| __asm volatile ( "SETPSW I" ); |
| |
| /* Increment the tick, and perform any processing the new tick value |
| * necessitates. Ensure IPL is at the max syscall value first. */ |
| portDISABLE_INTERRUPTS_FROM_KERNEL_ISR(); |
| { |
| if( xTaskIncrementTick() != pdFALSE ) |
| { |
| taskYIELD(); |
| } |
| } |
| portENABLE_INTERRUPTS_FROM_KERNEL_ISR(); |
| |
| #if configUSE_TICKLESS_IDLE == 1 |
| { |
| /* The CPU woke because of a tick. */ |
| ulTickFlag = pdTRUE; |
| |
| /* If this is the first tick since exiting tickless mode then the CMT |
| * compare match value needs resetting. */ |
| CMT0.CMCOR = ( uint16_t ) ulMatchValueForOneTick; |
| } |
| #endif |
| } |
| /*-----------------------------------------------------------*/ |
| |
| uint32_t ulPortGetIPL( void ) |
| { |
| __asm volatile |
| ( |
| "MVFC PSW, R1 \n" \ |
| "SHLR #24, R1 \n" \ |
| "RTS " |
| ); |
| |
| /* This will never get executed, but keeps the compiler from complaining. */ |
| return 0; |
| } |
| /*-----------------------------------------------------------*/ |
| |
| void vPortSetIPL( uint32_t ulNewIPL ) |
| { |
| __asm volatile |
| ( |
| "PUSH R5 \n" \ |
| "MVFC PSW, R5 \n" \ |
| "SHLL #24, R1 \n" \ |
| "AND #-0F000001H, R5 \n" \ |
| "OR R1, R5 \n" \ |
| "MVTC R5, PSW \n" \ |
| "POP R5 \n" \ |
| "RTS " |
| ); |
| } |
| /*-----------------------------------------------------------*/ |
| |
| static void prvSetupTimerInterrupt( void ) |
| { |
| /* Unlock. */ |
| SYSTEM.PRCR.WORD = portUNLOCK_KEY; |
| |
| /* Enable CMT0. */ |
| MSTP( CMT0 ) = 0; |
| |
| /* Lock again. */ |
| SYSTEM.PRCR.WORD = portLOCK_KEY; |
| |
| /* Interrupt on compare match. */ |
| CMT0.CMCR.BIT.CMIE = 1; |
| |
| /* Set the compare match value. */ |
| CMT0.CMCOR = ( uint16_t ) ulMatchValueForOneTick; |
| |
| /* Divide the PCLK. */ |
| #if portCLOCK_DIVISOR == 512 |
| { |
| CMT0.CMCR.BIT.CKS = 3; |
| } |
| #elif portCLOCK_DIVISOR == 128 |
| { |
| CMT0.CMCR.BIT.CKS = 2; |
| } |
| #elif portCLOCK_DIVISOR == 32 |
| { |
| CMT0.CMCR.BIT.CKS = 1; |
| } |
| #elif portCLOCK_DIVISOR == 8 |
| { |
| CMT0.CMCR.BIT.CKS = 0; |
| } |
| #else /* if portCLOCK_DIVISOR == 512 */ |
| { |
| #error Invalid portCLOCK_DIVISOR setting |
| } |
| #endif /* if portCLOCK_DIVISOR == 512 */ |
| |
| /* Enable the interrupt... */ |
| _IEN( _CMT0_CMI0 ) = 1; |
| |
| /* ...and set its priority to the application defined kernel priority. */ |
| _IPR( _CMT0_CMI0 ) = configKERNEL_INTERRUPT_PRIORITY; |
| |
| /* Start the timer. */ |
| CMT.CMSTR0.BIT.STR0 = 1; |
| } |
| /*-----------------------------------------------------------*/ |
| |
| #if configUSE_TICKLESS_IDLE == 1 |
| |
| static void prvSleep( TickType_t xExpectedIdleTime ) |
| { |
| /* Allow the application to define some pre-sleep processing. */ |
| configPRE_SLEEP_PROCESSING( xExpectedIdleTime ); |
| |
| /* xExpectedIdleTime being set to 0 by configPRE_SLEEP_PROCESSING() |
| * means the application defined code has already executed the WAIT |
| * instruction. */ |
| if( xExpectedIdleTime > 0 ) |
| { |
| __asm volatile ( "WAIT" ); |
| } |
| |
| /* Allow the application to define some post sleep processing. */ |
| configPOST_SLEEP_PROCESSING( xExpectedIdleTime ); |
| } |
| |
| #endif /* configUSE_TICKLESS_IDLE */ |
| /*-----------------------------------------------------------*/ |
| |
| #if configUSE_TICKLESS_IDLE == 1 |
| |
| void vPortSuppressTicksAndSleep( TickType_t xExpectedIdleTime ) |
| { |
| uint32_t ulMatchValue, ulCompleteTickPeriods, ulCurrentCount; |
| eSleepModeStatus eSleepAction; |
| |
| /* THIS FUNCTION IS CALLED WITH THE SCHEDULER SUSPENDED. */ |
| |
| /* Make sure the CMT reload value does not overflow the counter. */ |
| if( xExpectedIdleTime > xMaximumPossibleSuppressedTicks ) |
| { |
| xExpectedIdleTime = xMaximumPossibleSuppressedTicks; |
| } |
| |
| /* Calculate the reload value required to wait xExpectedIdleTime tick |
| * periods. */ |
| ulMatchValue = ulMatchValueForOneTick * xExpectedIdleTime; |
| |
| if( ulMatchValue > ulStoppedTimerCompensation ) |
| { |
| /* Compensate for the fact that the CMT is going to be stopped |
| * momentarily. */ |
| ulMatchValue -= ulStoppedTimerCompensation; |
| } |
| |
| /* Stop the CMT momentarily. The time the CMT 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. */ |
| CMT.CMSTR0.BIT.STR0 = 0; |
| |
| while( CMT.CMSTR0.BIT.STR0 == 1 ) |
| { |
| /* Nothing to do here. */ |
| } |
| |
| /* Critical section using the global interrupt bit as the i bit is |
| * automatically reset by the WAIT instruction. */ |
| __asm volatile ( "CLRPSW i" ); |
| |
| /* The tick flag is set to false before sleeping. If it is true when |
| * sleep mode is exited then sleep mode was probably exited because the |
| * tick was suppressed for the entire xExpectedIdleTime period. */ |
| ulTickFlag = pdFALSE; |
| |
| /* If a context switch is pending then abandon the low power entry as |
| * the context switch might have been pended by an external interrupt that |
| * requires processing. */ |
| eSleepAction = eTaskConfirmSleepModeStatus(); |
| |
| if( eSleepAction == eAbortSleep ) |
| { |
| /* Restart tick. */ |
| CMT.CMSTR0.BIT.STR0 = 1; |
| __asm volatile ( "SETPSW i" ); |
| } |
| else if( eSleepAction == eNoTasksWaitingTimeout ) |
| { |
| /* Protection off. */ |
| SYSTEM.PRCR.WORD = portUNLOCK_KEY; |
| |
| /* Ready for software standby with all clocks stopped. */ |
| SYSTEM.SBYCR.BIT.SSBY = 1; |
| |
| /* Protection on. */ |
| SYSTEM.PRCR.WORD = portLOCK_KEY; |
| |
| /* Sleep until something happens. Calling prvSleep() will |
| * automatically reset the i bit in the PSW. */ |
| prvSleep( xExpectedIdleTime ); |
| |
| /* Restart the CMT. */ |
| CMT.CMSTR0.BIT.STR0 = 1; |
| } |
| else |
| { |
| /* Protection off. */ |
| SYSTEM.PRCR.WORD = portUNLOCK_KEY; |
| |
| /* Ready for deep sleep mode. */ |
| SYSTEM.MSTPCRC.BIT.DSLPE = 1; |
| SYSTEM.MSTPCRA.BIT.MSTPA28 = 1; |
| SYSTEM.SBYCR.BIT.SSBY = 0; |
| |
| /* Protection on. */ |
| SYSTEM.PRCR.WORD = portLOCK_KEY; |
| |
| /* Adjust the match value to take into account that the current |
| * time slice is already partially complete. */ |
| ulMatchValue -= ( uint32_t ) CMT0.CMCNT; |
| CMT0.CMCOR = ( uint16_t ) ulMatchValue; |
| |
| /* Restart the CMT to count up to the new match value. */ |
| CMT0.CMCNT = 0; |
| CMT.CMSTR0.BIT.STR0 = 1; |
| |
| /* Sleep until something happens. Calling prvSleep() will |
| * automatically reset the i bit in the PSW. */ |
| prvSleep( xExpectedIdleTime ); |
| |
| /* Stop CMT. 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. */ |
| CMT.CMSTR0.BIT.STR0 = 0; |
| |
| while( CMT.CMSTR0.BIT.STR0 == 1 ) |
| { |
| /* Nothing to do here. */ |
| } |
| |
| ulCurrentCount = ( uint32_t ) CMT0.CMCNT; |
| |
| if( ulTickFlag != pdFALSE ) |
| { |
| /* The tick interrupt has already executed, although because |
| * this function is called with the scheduler suspended the actual |
| * tick processing will not occur until after this function has |
| * exited. Reset the match value with whatever remains of this |
| * tick period. */ |
| ulMatchValue = ulMatchValueForOneTick - ulCurrentCount; |
| CMT0.CMCOR = ( uint16_t ) ulMatchValue; |
| |
| /* 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 sleeping. The actual stepping of the tick appears |
| * later in this function. */ |
| ulCompleteTickPeriods = xExpectedIdleTime - 1UL; |
| } |
| else |
| { |
| /* Something other than the tick interrupt ended the sleep. |
| * How many complete tick periods passed while the processor was |
| * sleeping? */ |
| ulCompleteTickPeriods = ulCurrentCount / ulMatchValueForOneTick; |
| |
| /* The match value is set to whatever fraction of a single tick |
| * period remains. */ |
| ulMatchValue = ulCurrentCount - ( ulCompleteTickPeriods * ulMatchValueForOneTick ); |
| CMT0.CMCOR = ( uint16_t ) ulMatchValue; |
| } |
| |
| /* Restart the CMT so it runs up to the match value. The match value |
| * will get set to the value required to generate exactly one tick period |
| * the next time the CMT interrupt executes. */ |
| CMT0.CMCNT = 0; |
| CMT.CMSTR0.BIT.STR0 = 1; |
| |
| /* Wind the tick forward by the number of tick periods that the CPU |
| * remained in a low power state. */ |
| vTaskStepTick( ulCompleteTickPeriods ); |
| } |
| } |
| |
| #endif /* configUSE_TICKLESS_IDLE */ |
