| /* | |
| FreeRTOS V7.2.0 - Copyright (C) 2012 Real Time Engineers Ltd. | |
| *************************************************************************** | |
| * * | |
| * FreeRTOS tutorial books are available in pdf and paperback. * | |
| * Complete, revised, and edited pdf reference manuals are also * | |
| * available. * | |
| * * | |
| * Purchasing FreeRTOS documentation will not only help you, by * | |
| * ensuring you get running as quickly as possible and with an * | |
| * in-depth knowledge of how to use FreeRTOS, it will also help * | |
| * the FreeRTOS project to continue with its mission of providing * | |
| * professional grade, cross platform, de facto standard solutions * | |
| * for microcontrollers - completely free of charge! * | |
| * * | |
| * >>> See http://www.FreeRTOS.org/Documentation for details. <<< * | |
| * * | |
| * Thank you for using FreeRTOS, and thank you for your support! * | |
| * * | |
| *************************************************************************** | |
| 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. See the GNU General Public License for | |
| more details. You should have received a copy of the GNU General Public | |
| License and the FreeRTOS license exception along with FreeRTOS; if not it | |
| can be viewed here: http://www.freertos.org/a00114.html and also obtained | |
| by writing to Richard Barry, contact details for whom are available on the | |
| FreeRTOS WEB site. | |
| 1 tab == 4 spaces! | |
| *************************************************************************** | |
| * * | |
| * Having a problem? Start by reading the FAQ "My application does * | |
| * not run, what could be wrong? * | |
| * * | |
| * http://www.FreeRTOS.org/FAQHelp.html * | |
| * * | |
| *************************************************************************** | |
| http://www.FreeRTOS.org - Documentation, training, latest information, | |
| license and contact details. | |
| http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products, | |
| including FreeRTOS+Trace - an indispensable productivity tool. | |
| Real Time Engineers ltd license FreeRTOS to High Integrity Systems, who sell | |
| the code with commercial support, indemnification, and middleware, under | |
| the OpenRTOS brand: http://www.OpenRTOS.com. High Integrity Systems also | |
| provide a safety engineered and independently SIL3 certified version under | |
| the SafeRTOS brand: http://www.SafeRTOS.com. | |
| */ | |
| /*----------------------------------------------------------- | |
| * Implementation of functions defined in portable.h for the SH2A port. | |
| *----------------------------------------------------------*/ | |
| /* Scheduler includes. */ | |
| #include "FreeRTOS.h" | |
| #include "task.h" | |
| /* Library includes. */ | |
| #include "string.h" | |
| /* Hardware specifics. */ | |
| #include "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 ( ( portSTACK_TYPE ) 0x00030000 ) | |
| #define portINITIAL_FPSW ( ( portSTACK_TYPE ) 0x00000100 ) | |
| /* These macros allow a critical section to be added around the call to | |
| vTaskIncrementTick(), 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) ) | |
| /*-----------------------------------------------------------*/ | |
| /* | |
| * 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. | |
| */ | |
| void vSoftwareInterruptISR( void ) __attribute__((naked)); | |
| /* | |
| * The tick interrupt handler. | |
| */ | |
| void vTickISR( void ) __attribute__((interrupt)); | |
| /*-----------------------------------------------------------*/ | |
| extern void *pxCurrentTCB; | |
| /*-----------------------------------------------------------*/ | |
| /* | |
| * See header file for description. | |
| */ | |
| portSTACK_TYPE *pxPortInitialiseStack( portSTACK_TYPE *pxTopOfStack, pdTASK_CODE pxCode, void *pvParameters ) | |
| { | |
| /* R0 is not included as it is the stack pointer. */ | |
| *pxTopOfStack = 0x00; | |
| pxTopOfStack--; | |
| *pxTopOfStack = portINITIAL_PSW; | |
| pxTopOfStack--; | |
| *pxTopOfStack = ( portSTACK_TYPE ) 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 = 0xffffffff; /* r15. */ | |
| pxTopOfStack--; | |
| *pxTopOfStack = 0xeeeeeeee; | |
| 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 | |
| { | |
| pxTopOfStack -= 15; | |
| } | |
| #endif | |
| *pxTopOfStack = ( portSTACK_TYPE ) pvParameters; /* R1 */ | |
| pxTopOfStack--; | |
| *pxTopOfStack = portINITIAL_FPSW; | |
| pxTopOfStack--; | |
| *pxTopOfStack = 0x12345678; /* Accumulator. */ | |
| pxTopOfStack--; | |
| *pxTopOfStack = 0x87654321; /* Accumulator. */ | |
| return pxTopOfStack; | |
| } | |
| /*-----------------------------------------------------------*/ | |
| portBASE_TYPE xPortStartScheduler( void ) | |
| { | |
| extern void vApplicationSetupTimerInterrupt( 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. A demo application is provided to show a suitable example. */ | |
| vApplicationSetupTimerInterrupt(); | |
| /* 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(); | |
| } | |
| /* Should not get here. */ | |
| return pdFAIL; | |
| } | |
| /*-----------------------------------------------------------*/ | |
| void vPortEndScheduler( void ) | |
| { | |
| /* Not implemented as there is nothing to return to. */ | |
| } | |
| /*-----------------------------------------------------------*/ | |
| 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" \ | |
| "POP R15 \n" \ | |
| /* Floating point status word. */ | |
| "MVTC R15, FPSW \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 vSoftwareInterruptISR( 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 FPSW and accumulator. */ | |
| "MVFC FPSW, R15 \n" \ | |
| "PUSH.L R15 \n" \ | |
| "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" \ | |
| "POP R15 \n" \ | |
| "MVTC R15, FPSW \n" \ | |
| "POPM R1-R15 \n" \ | |
| "RTE \n" \ | |
| "NOP \n" \ | |
| "NOP " | |
| :: "i"(configMAX_SYSCALL_INTERRUPT_PRIORITY), "i"(configKERNEL_INTERRUPT_PRIORITY) | |
| ); | |
| } | |
| /*-----------------------------------------------------------*/ | |
| void vTickISR( 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(); | |
| { | |
| vTaskIncrementTick(); | |
| } | |
| portENABLE_INTERRUPTS_FROM_KERNEL_ISR(); | |
| /* Only select a new task if the preemptive scheduler is being used. */ | |
| #if( configUSE_PREEMPTION == 1 ) | |
| taskYIELD(); | |
| #endif | |
| } | |
| /*-----------------------------------------------------------*/ | |
| unsigned long 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( unsigned long 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 " | |
| ); | |
| } |