1;/*************************************************************************** 2; * Copyright (c) 2024 Microsoft Corporation 3; * 4; * This program and the accompanying materials are made available under the 5; * terms of the MIT License which is available at 6; * https://opensource.org/licenses/MIT. 7; * 8; * SPDX-License-Identifier: MIT 9; **************************************************************************/ 10; 11; 12;/**************************************************************************/ 13;/**************************************************************************/ 14;/** */ 15;/** ThreadX Component */ 16;/** */ 17;/** Thread */ 18;/** */ 19;/**************************************************************************/ 20;/**************************************************************************/ 21; 22; 23;#define TX_SOURCE_CODE 24; 25; 26;/* Include necessary system files. */ 27; 28;#include "tx_api.h" 29;#include "tx_thread.h" 30;#include "tx_timer.h" 31; 32; 33 .global __tx_thread_system_state 34 .global __tx_thread_current_ptr 35 .global __tx_thread_system_stack_ptr 36 .global __tx_thread_execute_ptr 37 .global __tx_timer_time_slice 38 .global __tx_thread_schedule 39 .global __tx_thread_preempt_disable 40 41 .text 42 43;/**************************************************************************/ 44;/* */ 45;/* FUNCTION RELEASE */ 46;/* */ 47;/* _tx_thread_context_restore RXv1/GNURX */ 48;/* 6.1.11 */ 49;/* AUTHOR */ 50;/* */ 51;/* William E. Lamie, Microsoft Corporation */ 52;/* */ 53;/* DESCRIPTION */ 54;/* */ 55;/* This function restores the interrupt context if it is processing a */ 56;/* nested interrupt. If not, it returns to the interrupt thread if no */ 57;/* preemption is necessary. Otherwise, if preemption is necessary or */ 58;/* if no thread was running, the function returns to the scheduler. */ 59;/* */ 60;/* INPUT */ 61;/* */ 62;/* None */ 63;/* */ 64;/* OUTPUT */ 65;/* */ 66;/* None */ 67;/* */ 68;/* CALLS */ 69;/* */ 70;/* _tx_thread_schedule Thread scheduling routine */ 71;/* */ 72;/* CALLED BY */ 73;/* */ 74;/* ISRs Interrupt Service Routines */ 75;/* */ 76;/* RELEASE HISTORY */ 77;/* */ 78;/* DATE NAME DESCRIPTION */ 79;/* */ 80;/* 08-02-2021 William E. Lamie Initial Version 6.1.8 */ 81;/* 10-15-2021 William E. Lamie Modified comment(s), and */ 82;/* removed unnecessary stack */ 83;/* type placement, */ 84;/* resulting in version 6.1.9 */ 85;/* 01-31-2022 William E. Lamie Modified comment(s), */ 86;/* resulting in version 6.1.10 */ 87;/* 04-25-2022 William E. Lamie Modified comment(s), */ 88;/* resulting in version 6.1.11 */ 89;/* */ 90;/**************************************************************************/ 91;VOID _tx_thread_context_restore(VOID) 92;{ 93 .global __tx_thread_context_restore 94__tx_thread_context_restore: 95; 96; /* Lockout interrupts. */ 97 98 CLRPSW I ; Disable interrupts 99 100; /* Determine if interrupts are nested. */ 101; if (--_tx_thread_system_state) 102; { 103 104 MOV.L #__tx_thread_system_state, R1 105 MOV.L [R1], R2 106 SUB #1, R2 107 MOV.L R2,[R1] 108 BEQ __tx_thread_not_nested_restore 109 110; 111; /* Interrupts are nested. */ 112; 113; /* Recover the saved registers from the interrupt stack 114; and return to the point of interrupt. */ 115; 116__tx_thread_nested_restore: 117 POPM R14-R15 ; Restore R14-R15 118 POPM R3-R5 ; Restore R3-R5 119 POPM R1-R2 ; Restore R1-R2 120 RTE ; Return to point of interrupt, restore PSW including IPL 121; } 122 123__tx_thread_not_nested_restore: 124; 125; /* Determine if a thread was interrupted and no preemption is required. */ 126; else if (((_tx_thread_current_ptr) && (_tx_thread_current_ptr == _tx_thread_execute_ptr) 127; || (_tx_thread_preempt_disable)) 128; { 129 130 MOV.L #__tx_thread_current_ptr, R1 ; Pickup current thread ptr address 131 MOV.L [R1], R2 132 CMP #0, R2 133 BEQ __tx_thread_idle_system_restore 134 135 MOV.L #__tx_thread_preempt_disable, R3 ; Pick up preempt disable flag 136 MOV.L [R3], R3 137 CMP #0, R3 138 BNE __tx_thread_no_preempt_restore ; If pre-empt disable flag set, we simply return to the original point of interrupt regardless 139 140 MOV.L #__tx_thread_execute_ptr, R3 ; (_tx_thread_current_ptr != _tx_thread_execute_ptr) 141 CMP [R3], R2 142 BNE __tx_thread_preempt_restore ; Jump to pre-empt restoring 143; 144__tx_thread_no_preempt_restore: 145 SETPSW U ; User stack 146 POPM R14-R15 ; Restore R14-R15 147 POPM R3-R5 ; Restore R3-R5 148 POPM R1-R2 ; Restore R1-R2 149 RTE ; Return to point of interrupt, restore PSW including IPL 150 151; } 152; else 153; { 154 155__tx_thread_preempt_restore: 156 157; /* Save the remaining time-slice and disable it. */ 158; if (_tx_timer_time_slice) 159; { 160 161 MOV.L #__tx_timer_time_slice, R3 ; Pickup time-slice address 162 MOV.L [R3],R4 ; Pickup actual time-slice 163 CMP #0, R4 164 BEQ __tx_thread_dont_save_ts ; No time slice to save 165; 166; _tx_thread_current_ptr -> tx_thread_time_slice = _tx_timer_time_slice; 167; _tx_timer_time_slice = 0; 168; 169 MOV.L R4,24[R2] ; Save thread's time slice 170 MOV.L #0,R4 ; Clear value 171 MOV.L R4,[R3] ; Disable global time slice flag 172; } 173__tx_thread_dont_save_ts: 174; 175; /* Now store the remaining registers! */ 176 177 SETPSW U ; User stack 178 PUSHM R6-R13 179 180 MVFACHI R5 181 MVFACMI R6 182 PUSHM R5-R6 183 184; 185; /* Clear the current task pointer. */ 186; _tx_thread_current_ptr = TX_NULL; 187; R1 -> _tx_thread_current_ptr 188; R2 -> *_tx_thread_current_ptr 189 190 MOV.L R0,8[R2] ; Save thread's stack pointer in thread control block 191 MOV.L #0,R2 ; Build NULL value 192 MOV.L R2,[R1] ; Set current thread to NULL 193 194; /* Return to the scheduler. */ 195; _tx_thread_schedule(); 196 197__tx_thread_idle_system_restore: 198 MVTC #0, PSW ; Reset interrupt priority level to 0 199 BRA __tx_thread_schedule ; Jump to scheduler 200; } 201; 202;} 203; 204 .end 205
