/* * 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 * */ /*----------------------------------------------------------- * Implementation of functions defined in portable.h for the SH2A port. *----------------------------------------------------------*/ /* Scheduler includes. */ #include "FreeRTOS.h" #include "task.h" /* Library includes. */ #include "string.h" /*-----------------------------------------------------------*/ /* The SR assigned to a newly created task. The only important thing in this * value is for all interrupts to be enabled. */ #define portINITIAL_SR ( 0UL ) /* Dimensions the array into which the floating point context is saved. * Allocate enough space for FPR0 to FPR15, FPUL and FPSCR, each of which is 4 * bytes big. If this number is changed then the 72 in portasm.src also needs * changing. */ #define portFLOP_REGISTERS_TO_STORE ( 18 ) #define portFLOP_STORAGE_SIZE ( portFLOP_REGISTERS_TO_STORE * 4 ) #if ( configSUPPORT_DYNAMIC_ALLOCATION == 0 ) #error configSUPPORT_DYNAMIC_ALLOCATION must be 1 to use this port. #endif /*-----------------------------------------------------------*/ /* * The TRAPA handler used to force a context switch. */ void vPortYield( void ); /* * Function to start the first task executing - defined in portasm.src. */ extern void vPortStartFirstTask( void ); /* * Obtains the current GBR value - defined in portasm.src. */ extern uint32_t ulPortGetGBR( void ); /*-----------------------------------------------------------*/ /* * See header file for description. */ StackType_t * pxPortInitialiseStack( StackType_t * pxTopOfStack, TaskFunction_t pxCode, void * pvParameters ) { /* Mark the end of the stack - used for debugging only and can be removed. */ *pxTopOfStack = 0x11111111UL; pxTopOfStack--; *pxTopOfStack = 0x22222222UL; pxTopOfStack--; *pxTopOfStack = 0x33333333UL; pxTopOfStack--; /* SR. */ *pxTopOfStack = portINITIAL_SR; pxTopOfStack--; /* PC. */ *pxTopOfStack = ( uint32_t ) pxCode; pxTopOfStack--; /* PR. */ *pxTopOfStack = 15; pxTopOfStack--; /* 14. */ *pxTopOfStack = 14; pxTopOfStack--; /* R13. */ *pxTopOfStack = 13; pxTopOfStack--; /* R12. */ *pxTopOfStack = 12; pxTopOfStack--; /* R11. */ *pxTopOfStack = 11; pxTopOfStack--; /* R10. */ *pxTopOfStack = 10; pxTopOfStack--; /* R9. */ *pxTopOfStack = 9; pxTopOfStack--; /* R8. */ *pxTopOfStack = 8; pxTopOfStack--; /* R7. */ *pxTopOfStack = 7; pxTopOfStack--; /* R6. */ *pxTopOfStack = 6; pxTopOfStack--; /* R5. */ *pxTopOfStack = 5; pxTopOfStack--; /* R4. */ *pxTopOfStack = ( uint32_t ) pvParameters; pxTopOfStack--; /* R3. */ *pxTopOfStack = 3; pxTopOfStack--; /* R2. */ *pxTopOfStack = 2; pxTopOfStack--; /* R1. */ *pxTopOfStack = 1; pxTopOfStack--; /* R0 */ *pxTopOfStack = 0; pxTopOfStack--; /* MACL. */ *pxTopOfStack = 16; pxTopOfStack--; /* MACH. */ *pxTopOfStack = 17; pxTopOfStack--; /* GBR. */ *pxTopOfStack = ulPortGetGBR(); /* GBR = global base register. * VBR = vector base register. * TBR = jump table base register. * R15 is the stack pointer. */ return pxTopOfStack; } /*-----------------------------------------------------------*/ BaseType_t xPortStartScheduler( void ) { extern void vApplicationSetupTimerInterrupt( void ); /* 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(); /* Start the first task. This will only restore the standard registers and * not the flop registers. This does not really matter though because the only * flop register that is initialised to a particular value is fpscr, and it is * only initialised to the current value, which will still be the current value * when the first task starts executing. */ trapa( portSTART_SCHEDULER_TRAP_NO ); /* Should not get here. */ return pdFAIL; } /*-----------------------------------------------------------*/ void vPortEndScheduler( void ) { /* Not implemented as there is nothing to return to. */ } /*-----------------------------------------------------------*/ void vPortYield( void ) { int32_t lInterruptMask; /* Ensure the yield trap runs at the same priority as the other interrupts * that can cause a context switch. */ lInterruptMask = get_imask(); /* taskYIELD() can only be called from a task, not an interrupt, so the * current interrupt mask can only be 0 or portKERNEL_INTERRUPT_PRIORITY and * the mask can be set without risk of accidentally lowering the mask value. */ set_imask( portKERNEL_INTERRUPT_PRIORITY ); trapa( portYIELD_TRAP_NO ); /* Restore the interrupt mask to whatever it was previously (when the * function was entered). */ set_imask( ( int ) lInterruptMask ); } /*-----------------------------------------------------------*/ BaseType_t xPortUsesFloatingPoint( TaskHandle_t xTask ) { uint32_t * pulFlopBuffer; BaseType_t xReturn; extern void * volatile pxCurrentTCB; /* This function tells the kernel that the task referenced by xTask is * going to use the floating point registers and therefore requires the * floating point registers saved as part of its context. */ /* Passing NULL as xTask is used to indicate that the calling task is the * subject task - so pxCurrentTCB is the task handle. */ if( xTask == NULL ) { xTask = ( TaskHandle_t ) pxCurrentTCB; } /* Allocate a buffer large enough to hold all the flop registers. */ pulFlopBuffer = ( uint32_t * ) pvPortMalloc( portFLOP_STORAGE_SIZE ); if( pulFlopBuffer != NULL ) { /* Start with the registers in a benign state. */ memset( ( void * ) pulFlopBuffer, 0x00, portFLOP_STORAGE_SIZE ); /* The first thing to get saved in the buffer is the FPSCR value - * initialise this to the current FPSCR value. */ *pulFlopBuffer = get_fpscr(); /* Use the task tag to point to the flop buffer. Pass pointer to just * above the buffer because the flop save routine uses a pre-decrement. */ vTaskSetApplicationTaskTag( xTask, ( void * ) ( pulFlopBuffer + portFLOP_REGISTERS_TO_STORE ) ); xReturn = pdPASS; } else { xReturn = pdFAIL; } return xReturn; } /*-----------------------------------------------------------*/