;/* ; * Copyright (c) 2013-2021 Arm Limited. All rights reserved. ; * ; * SPDX-License-Identifier: Apache-2.0 ; * ; * Licensed under the Apache License, Version 2.0 (the License); you may ; * not use this file except in compliance with the License. ; * You may obtain a copy of the License at ; * ; * www.apache.org/licenses/LICENSE-2.0 ; * ; * Unless required by applicable law or agreed to in writing, software ; * distributed under the License is distributed on an AS IS BASIS, WITHOUT ; * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. ; * See the License for the specific language governing permissions and ; * limitations under the License. ; * ; * ----------------------------------------------------------------------------- ; * ; * Project: CMSIS-RTOS RTX ; * Title: ARMv7-M Exception handlers ; * ; * ----------------------------------------------------------------------------- ; */ NAME irq_armv7m.s #ifdef __ARMVFP__ FPU_USED EQU 1 #else FPU_USED EQU 0 #endif I_T_RUN_OFS EQU 20 ; osRtxInfo.thread.run offset TCB_SP_OFS EQU 56 ; TCB.SP offset TCB_SF_OFS EQU 34 ; TCB.stack_frame offset FPCCR EQU 0xE000EF34 ; FPCCR Address osRtxErrorStackOverflow\ EQU 1 ; Stack overflow PRESERVE8 SECTION .rodata:DATA:NOROOT(2) EXPORT irqRtxLib irqRtxLib DCB 0 ; Non weak library reference THUMB SECTION .text:CODE:NOROOT(2) SVC_Handler EXPORT SVC_Handler IMPORT osRtxUserSVC IMPORT osRtxInfo #ifdef RTX_STACK_CHECK IMPORT osRtxThreadStackCheck IMPORT osRtxKernelErrorNotify #endif TST LR,#0x04 ; Determine return stack from EXC_RETURN bit 2 ITE EQ MRSEQ R0,MSP ; Get MSP if return stack is MSP MRSNE R0,PSP ; Get PSP if return stack is PSP LDR R1,[R0,#24] ; Load saved PC from stack LDRB R1,[R1,#-2] ; Load SVC number CMP R1,#0 ; Check SVC number BNE SVC_User ; Branch if not SVC 0 PUSH {R0,LR} ; Save SP and EXC_RETURN LDM R0,{R0-R3,R12} ; Load function parameters and address from stack BLX R12 ; Call service function POP {R12,LR} ; Restore SP and EXC_RETURN STM R12,{R0-R1} ; Store function return values SVC_Context LDR R3,=osRtxInfo+I_T_RUN_OFS; Load address of osRtxInfo.thread.run LDM R3,{R1,R2} ; Load osRtxInfo.thread.run: curr & next CMP R1,R2 ; Check if thread switch is required IT EQ BXEQ LR ; Exit when threads are the same STR R2,[R3] ; osRtxInfo.thread.run: curr = next #if (FPU_USED != 0) CBNZ R1,SVC_ContextSave ; Branch if running thread is not deleted SVC_FP_LazyState TST LR,#0x10 ; Determine stack frame from EXC_RETURN bit 4 BNE SVC_ContextRestore ; Branch if not extended stack frame LDR R3,=FPCCR ; FPCCR Address LDR R0,[R3] ; Load FPCCR BIC R0,R0,#1 ; Clear LSPACT (Lazy state preservation) STR R0,[R3] ; Store FPCCR B SVC_ContextRestore ; Branch to context restore handling #else CBZ R1,SVC_ContextRestore ; Branch if running thread is deleted #endif SVC_ContextSave #ifdef RTX_STACK_CHECK SUB R12,R12,#32 ; Calculate SP: space for R4..R11 #if (FPU_USED != 0) TST LR,#0x10 ; Determine stack frame from EXC_RETURN bit 4 IT EQ ; If extended stack frame SUBEQ R12,R12,#64 ; Additional space for S16..S31 STRB LR, [R1,#TCB_SF_OFS] ; Store stack frame information #endif STR R12,[R1,#TCB_SP_OFS] ; Store SP PUSH {R1,R2} ; Save osRtxInfo.thread.run: curr & next MOV R0,R1 ; Parameter: osRtxInfo.thread.run.curr BL osRtxThreadStackCheck ; Check if thread stack is overrun POP {R1,R2} ; Restore osRtxInfo.thread.run: curr & next CBNZ R0,SVC_ContextSaveRegs ; Branch when stack check is ok #if (FPU_USED != 0) MOV R4,R1 ; Save osRtxInfo.thread.run.curr #endif MOV R0,#osRtxErrorStackOverflow ; Parameter: r0=code, r1=object_id BL osRtxKernelErrorNotify ; Call osRtxKernelErrorNotify LDR R3,=osRtxInfo+I_T_RUN_OFS ; Load address of osRtxInfo.thread.run LDR R2,[R3,#4] ; Load osRtxInfo.thread.run: next STR R2,[R3] ; osRtxInfo.thread.run: curr = next #if (FPU_USED != 0) LDRB LR,[R4,#TCB_SF_OFS] ; Load stack frame information B SVC_FP_LazyState ; Branch to FP lazy state handling #else B SVC_ContextRestore ; Branch to context restore handling #endif SVC_ContextSaveRegs LDR R12,[R1,#TCB_SP_OFS] ; Load SP #if (FPU_USED != 0) LDRB LR, [R1,#TCB_SF_OFS] ; Load stack frame information TST LR,#0x10 ; Determine stack frame from EXC_RETURN bit 4 IT EQ ; If extended stack frame VSTMIAEQ R12!,{S16-S31} ; Save VFP S16..S31 #endif STM R12,{R4-R11} ; Save R4..R11 #else STMDB R12!,{R4-R11} ; Save R4..R11 #if (FPU_USED != 0) TST LR,#0x10 ; Determine stack frame from EXC_RETURN bit 4 IT EQ ; If extended stack frame VSTMDBEQ R12!,{S16-S31} ; Save VFP S16.S31 STRB LR, [R1,#TCB_SF_OFS] ; Store stack frame information #endif STR R12,[R1,#TCB_SP_OFS] ; Store SP #endif SVC_ContextRestore LDR R0,[R2,#TCB_SP_OFS] ; Load SP #if (FPU_USED != 0) LDRB R1,[R2,#TCB_SF_OFS] ; Load stack frame information ORN LR,R1,#0xFF ; Set EXC_RETURN TST LR,#0x10 ; Determine stack frame from EXC_RETURN bit 4 IT EQ ; If extended stack frame VLDMIAEQ R0!,{S16-S31} ; Restore VFP S16..S31 #else MVN LR,#~0xFFFFFFFD ; Set EXC_RETURN value #endif LDMIA R0!,{R4-R11} ; Restore R4..R11 MSR PSP,R0 ; Set PSP SVC_Exit BX LR ; Exit from handler SVC_User LDR R2,=osRtxUserSVC ; Load address of SVC table LDR R3,[R2] ; Load SVC maximum number CMP R1,R3 ; Check SVC number range BHI SVC_Exit ; Branch if out of range PUSH {R0,LR} ; Save SP and EXC_RETURN LDR R12,[R2,R1,LSL #2] ; Load address of SVC function LDM R0,{R0-R3} ; Load function parameters from stack BLX R12 ; Call service function POP {R12,LR} ; Restore SP and EXC_RETURN STR R0,[R12] ; Store function return value BX LR ; Return from handler PendSV_Handler EXPORT PendSV_Handler IMPORT osRtxPendSV_Handler PUSH {R0,LR} ; Save EXC_RETURN BL osRtxPendSV_Handler ; Call osRtxPendSV_Handler POP {R0,LR} ; Restore EXC_RETURN MRS R12,PSP ; Save PSP to R12 B SVC_Context ; Branch to context handling SysTick_Handler EXPORT SysTick_Handler IMPORT osRtxTick_Handler PUSH {R0,LR} ; Save EXC_RETURN BL osRtxTick_Handler ; Call osRtxTick_Handler POP {R0,LR} ; Restore EXC_RETURN MRS R12,PSP ; Save PSP to R12 B SVC_Context ; Branch to context handling END