| ;/* |
| ; * 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 |
| ; * |
| ; */ |
| |
| ; * The definition of the "register test" tasks, as described at the top of |
| ; * main.c |
| |
| .include data_model.h |
| |
| .global xTaskIncrementTick |
| .global vTaskSwitchContext |
| .global vPortSetupTimerInterrupt |
| .global pxCurrentTCB |
| .global usCriticalNesting |
| |
| .def vPortPreemptiveTickISR |
| .def vPortCooperativeTickISR |
| .def vPortYield |
| .def xPortStartScheduler |
| |
| ;----------------------------------------------------------- |
| |
| portSAVE_CONTEXT .macro |
| |
| ;Save the remaining registers. |
| pushm_x #12, r15 |
| movx.w &usCriticalNesting, r14 |
| push_x r14 |
| mov_x &pxCurrentTCB, r12 |
| mov_x sp, 0( r12 ) |
| .endm |
| ;----------------------------------------------------------- |
| |
| portRESTORE_CONTEXT .macro |
| |
| mov_x &pxCurrentTCB, r12 |
| mov_x @r12, sp |
| pop_x r15 |
| movx.w r15, &usCriticalNesting |
| popm_x #12, r15 |
| nop |
| pop.w sr |
| nop |
| ret_x |
| .endm |
| ;----------------------------------------------------------- |
| |
| ;* |
| ;* The RTOS tick ISR. |
| ;* |
| ;* If the cooperative scheduler is in use this simply increments the tick |
| ;* count. |
| ;* |
| ;* If the preemptive scheduler is in use a context switch can also occur. |
| ;*/ |
| |
| .text |
| .align 2 |
| |
| vPortPreemptiveTickISR: .asmfunc |
| |
| ; The sr is not saved in portSAVE_CONTEXT() because vPortYield() needs |
| ;to save it manually before it gets modified (interrupts get disabled). |
| push.w sr |
| portSAVE_CONTEXT |
| |
| call_x #xTaskIncrementTick |
| call_x #vTaskSwitchContext |
| |
| portRESTORE_CONTEXT |
| .endasmfunc |
| ;----------------------------------------------------------- |
| |
| .align 2 |
| |
| vPortCooperativeTickISR: .asmfunc |
| |
| ; The sr is not saved in portSAVE_CONTEXT() because vPortYield() needs |
| ;to save it manually before it gets modified (interrupts get disabled). |
| push.w sr |
| portSAVE_CONTEXT |
| |
| call_x #xTaskIncrementTick |
| |
| portRESTORE_CONTEXT |
| |
| .endasmfunc |
| ;----------------------------------------------------------- |
| |
| ; |
| ; Manual context switch called by the portYIELD() macro. |
| ; |
| |
| .align 2 |
| |
| vPortYield: .asmfunc |
| |
| ; The sr needs saving before it is modified. |
| push.w sr |
| |
| ; Now the SR is stacked we can disable interrupts. |
| dint |
| nop |
| |
| ; Save the context of the current task. |
| portSAVE_CONTEXT |
| |
| ; Select the next task to run. |
| call_x #vTaskSwitchContext |
| |
| ; Restore the context of the new task. |
| portRESTORE_CONTEXT |
| .endasmfunc |
| ;----------------------------------------------------------- |
| |
| |
| ; |
| ; Start off the scheduler by initialising the RTOS tick timer, then restoring |
| ; the context of the first task. |
| ; |
| |
| .align 2 |
| |
| xPortStartScheduler: .asmfunc |
| |
| ; Setup the hardware to generate the tick. Interrupts are disabled |
| ; when this function is called. |
| call_x #vPortSetupTimerInterrupt |
| |
| ; Restore the context of the first task that is going to run. |
| portRESTORE_CONTEXT |
| .endasmfunc |
| ;----------------------------------------------------------- |
| |
| .end |