| /* |
| * 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 |
| * |
| */ |
| |
| /* Standard includes. */ |
| #include <stdlib.h> |
| |
| /* Kernel includes. */ |
| #include "FreeRTOS.h" |
| #include "task.h" |
| |
| /* Machine includes */ |
| #include <machine/counter.h> |
| #include <machine/ic.h> |
| /*-----------------------------------------------------------*/ |
| |
| /* The initial PSR has the Previous Interrupt Enabled (PIEN) flag set. */ |
| #define portINITIAL_PSR ( 0x00020000 ) |
| |
| /*-----------------------------------------------------------*/ |
| |
| /* |
| * Perform any hardware configuration necessary to generate the tick interrupt. |
| */ |
| static void prvSetupTimerInterrupt( void ); |
| /*-----------------------------------------------------------*/ |
| |
| StackType_t * pxPortInitialiseStack( StackType_t * pxTopOfStack, |
| TaskFunction_t pxCode, |
| void * pvParameters ) |
| { |
| /* Make space on the stack for the context - this leaves a couple of spaces |
| * empty. */ |
| pxTopOfStack -= 20; |
| |
| /* Fill the registers with known values to assist debugging. */ |
| pxTopOfStack[ 16 ] = 0; |
| pxTopOfStack[ 15 ] = portINITIAL_PSR; |
| pxTopOfStack[ 14 ] = ( uint32_t ) pxCode; |
| pxTopOfStack[ 13 ] = 0x00000000UL; /* R15. */ |
| pxTopOfStack[ 12 ] = 0x00000000UL; /* R14. */ |
| pxTopOfStack[ 11 ] = 0x0d0d0d0dUL; |
| pxTopOfStack[ 10 ] = 0x0c0c0c0cUL; |
| pxTopOfStack[ 9 ] = 0x0b0b0b0bUL; |
| pxTopOfStack[ 8 ] = 0x0a0a0a0aUL; |
| pxTopOfStack[ 7 ] = 0x09090909UL; |
| pxTopOfStack[ 6 ] = 0x08080808UL; |
| pxTopOfStack[ 5 ] = 0x07070707UL; |
| pxTopOfStack[ 4 ] = 0x06060606UL; |
| pxTopOfStack[ 3 ] = 0x05050505UL; |
| pxTopOfStack[ 2 ] = 0x04040404UL; |
| pxTopOfStack[ 1 ] = 0x03030303UL; |
| pxTopOfStack[ 0 ] = ( uint32_t ) pvParameters; |
| |
| return pxTopOfStack; |
| } |
| /*-----------------------------------------------------------*/ |
| |
| BaseType_t xPortStartScheduler( void ) |
| { |
| /* Set-up the timer interrupt. */ |
| prvSetupTimerInterrupt(); |
| |
| /* Integrated Interrupt Controller: Enable all interrupts. */ |
| ic->ien = 1; |
| |
| /* Restore callee saved registers. */ |
| portRESTORE_CONTEXT(); |
| |
| /* Should not get here. */ |
| return 0; |
| } |
| /*-----------------------------------------------------------*/ |
| |
| static void prvSetupTimerInterrupt( void ) |
| { |
| /* Enable timer interrupts */ |
| counter1->reload = ( configCPU_CLOCK_HZ / configTICK_RATE_HZ ) - 1; |
| counter1->value = counter1->reload; |
| counter1->mask = 1; |
| |
| /* Set the IRQ Handler priority and enable it. */ |
| irq[ IRQ_COUNTER1 ].ien = 1; |
| } |
| /*-----------------------------------------------------------*/ |
| |
| /* Trap 31 handler. */ |
| void interrupt31_handler( void ) __attribute__( ( naked ) ); |
| void interrupt31_handler( void ) |
| { |
| portSAVE_CONTEXT(); |
| __asm volatile ( "call vTaskSwitchContext" ); |
| portRESTORE_CONTEXT(); |
| } |
| /*-----------------------------------------------------------*/ |
| |
| static void prvProcessTick( void ) __attribute__( ( noinline ) ); |
| static void prvProcessTick( void ) |
| { |
| if( xTaskIncrementTick() != pdFALSE ) |
| { |
| vTaskSwitchContext(); |
| } |
| |
| /* Clear the Tick Interrupt. */ |
| counter1->expired = 0; |
| } |
| /*-----------------------------------------------------------*/ |
| |
| /* Timer 1 interrupt handler, used for tick interrupt. */ |
| void interrupt7_handler( void ) __attribute__( ( naked ) ); |
| void interrupt7_handler( void ) |
| { |
| portSAVE_CONTEXT(); |
| prvProcessTick(); |
| portRESTORE_CONTEXT(); |
| } |
| /*-----------------------------------------------------------*/ |
| |
| void vPortEndScheduler( void ) |
| { |
| /* Nothing to do. Unlikely to want to end. */ |
| } |
| /*-----------------------------------------------------------*/ |