/*---------------------------------------------------------------------------- * CMSIS-RTOS - RTX *---------------------------------------------------------------------------- * Name: HAL_CM0.S * Purpose: Hardware Abstraction Layer for Cortex-M0 * Rev.: V4.70 *---------------------------------------------------------------------------- * * Copyright (c) 1999-2009 KEIL, 2009-2017 ARM Germany GmbH. 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. *---------------------------------------------------------------------------*/ NAME HAL_CM0.S #define TCB_TSTACK 40 EXTERN os_flags EXTERN os_tsk EXTERN rt_alloc_box EXTERN rt_free_box EXTERN rt_stk_check EXTERN rt_pop_req EXTERN rt_systick EXTERN os_tick_irqack EXTERN SVC_Table EXTERN SVC_Count /*---------------------------------------------------------------------------- * Functions *---------------------------------------------------------------------------*/ SECTION .text:CODE:NOROOT(2) THUMB /*--------------------------- rt_set_PSP ------------------------------------*/ ; void rt_set_PSP (U32 stack); PUBLIC rt_set_PSP rt_set_PSP: MSR PSP,R0 BX LR /*--------------------------- rt_get_PSP ------------------------------------*/ ; U32 rt_get_PSP (void); PUBLIC rt_get_PSP rt_get_PSP: MRS R0,PSP BX LR /*--------------------------- os_set_env ------------------------------------*/ ; void os_set_env (void); /* Switch to Unprivileged/Privileged Thread mode, use PSP. */ PUBLIC os_set_env os_set_env: MOV R0,SP /* PSP = MSP */ MSR PSP,R0 LDR R0,=os_flags LDRB R0,[R0] LSLS R0,#31 BNE PrivilegedE MOVS R0,#0x03 /* Unprivileged Thread mode, use PSP */ MSR CONTROL,R0 BX LR PrivilegedE: MOVS R0,#0x02 /* Privileged Thread mode, use PSP */ MSR CONTROL,R0 BX LR /*--------------------------- _alloc_box ------------------------------------*/ ; void *_alloc_box (void *box_mem); /* Function wrapper for Unprivileged/Privileged mode. */ PUBLIC _alloc_box _alloc_box: LDR R3,=rt_alloc_box MOV R12,R3 MRS R3,IPSR LSLS R3,#24 BNE PrivilegedA MRS R3,CONTROL LSLS R3,#31 BEQ PrivilegedA SVC 0 BX LR PrivilegedA: BX R12 /*--------------------------- _free_box -------------------------------------*/ ; U32 _free_box (void *box_mem, void *box); /* Function wrapper for Unprivileged/Privileged mode. */ PUBLIC _free_box _free_box: LDR R3,=rt_free_box MOV R12,R3 MRS R3,IPSR LSLS R3,#24 BNE PrivilegedF MRS R3,CONTROL LSLS R3,#31 BEQ PrivilegedF SVC 0 BX LR PrivilegedF: BX R12 /*-------------------------- SVC_Handler ------------------------------------*/ ; void SVC_Handler (void); PUBLIC SVC_Handler SVC_Handler: MRS R0,PSP /* Read PSP */ LDR R1,[R0,#24] /* Read Saved PC from Stack */ SUBS R1,R1,#2 /* Point to SVC Instruction */ LDRB R1,[R1] /* Load SVC Number */ CMP R1,#0 BNE SVC_User /* User SVC Number > 0 */ MOV LR,R4 LDMIA R0,{R0-R3,R4} /* Read R0-R3,R12 from stack */ MOV R12,R4 MOV R4,LR BLX R12 /* Call SVC Function */ MRS R3,PSP /* Read PSP */ STMIA R3!,{R0-R2} /* Store return values */ LDR R3,=os_tsk LDMIA R3!,{R1,R2} /* os_tsk.run, os_tsk.next */ CMP R1,R2 BEQ SVC_Exit /* no task switch */ SUBS R3,#8 CMP R1,#0 /* Runtask deleted? */ BEQ SVC_Next MRS R0,PSP /* Read PSP */ SUBS R0,R0,#32 /* Adjust Start Address */ STR R0,[R1,#TCB_TSTACK] /* Update os_tsk.run->tsk_stack */ STMIA R0!,{R4-R7} /* Save old context (R4-R7) */ MOV R4,R8 MOV R5,R9 MOV R6,R10 MOV R7,R11 STMIA R0!,{R4-R7} /* Save old context (R8-R11) */ PUSH {R2,R3} BL rt_stk_check /* Check for Stack overflow */ POP {R2,R3} SVC_Next: STR R2,[R3] /* os_tsk.run = os_tsk.next */ LDR R0,[R2,#TCB_TSTACK] /* os_tsk.next->tsk_stack */ ADDS R0,R0,#16 /* Adjust Start Address */ LDMIA R0!,{R4-R7} /* Restore new Context (R8-R11) */ MOV R8,R4 MOV R9,R5 MOV R10,R6 MOV R11,R7 MSR PSP,R0 /* Write PSP */ SUBS R0,R0,#32 /* Adjust Start Address */ LDMIA R0!,{R4-R7} /* Restore new Context (R4-R7) */ SVC_Exit: MOVS R0,#~0xFFFFFFFD /* Set EXC_RETURN value */ MVNS R0,R0 BX R0 /* RETI to Thread Mode, use PSP */ /*------------------- User SVC ------------------------------*/ SVC_User: PUSH {R4,LR} /* Save Registers */ LDR R2,=SVC_Count LDR R2,[R2] CMP R1,R2 BHI SVC_Done /* Overflow */ LDR R4,=SVC_Table-4 LSLS R1,R1,#2 LDR R4,[R4,R1] /* Load SVC Function Address */ MOV LR,R4 LDMIA R0,{R0-R3,R4} /* Read R0-R3,R12 from stack */ MOV R12,R4 BLX LR /* Call SVC Function */ MRS R4,PSP /* Read PSP */ STMIA R4!,{R0-R3} /* Function return values */ SVC_Done: POP {R4,PC} /* RETI */ /*-------------------------- PendSV_Handler ---------------------------------*/ ; void PendSV_Handler (void); PUBLIC PendSV_Handler PendSV_Handler: BL rt_pop_req Sys_Switch: LDR R3,=os_tsk LDMIA R3!,{R1,R2} /* os_tsk.run, os_tsk.next */ CMP R1,R2 BEQ Sys_Exit /* no task switch */ SUBS R3,#8 MRS R0,PSP /* Read PSP */ SUBS R0,R0,#32 /* Adjust Start Address */ STR R0,[R1,#TCB_TSTACK] /* Update os_tsk.run->tsk_stack */ STMIA R0!,{R4-R7} /* Save old context (R4-R7) */ MOV R4,R8 MOV R5,R9 MOV R6,R10 MOV R7,R11 STMIA R0!,{R4-R7} /* Save old context (R8-R11) */ PUSH {R2,R3} BL rt_stk_check /* Check for Stack overflow */ POP {R2,R3} STR R2,[R3] /* os_tsk.run = os_tsk.next */ LDR R0,[R2,#TCB_TSTACK] /* os_tsk.next->tsk_stack */ ADDS R0,R0,#16 /* Adjust Start Address */ LDMIA R0!,{R4-R7} /* Restore new Context (R8-R11) */ MOV R8,R4 MOV R9,R5 MOV R10,R6 MOV R11,R7 MSR PSP,R0 /* Write PSP */ SUBS R0,R0,#32 /* Adjust Start Address */ LDMIA R0!,{R4-R7} /* Restore new Context (R4-R7) */ Sys_Exit: MOVS R0,#~0xFFFFFFFD /* Set EXC_RETURN value */ MVNS R0,R0 BX R0 /* RETI to Thread Mode, use PSP */ /*-------------------------- SysTick_Handler --------------------------------*/ ; void SysTick_Handler (void); PUBLIC SysTick_Handler SysTick_Handler: BL rt_systick B Sys_Switch /*-------------------------- OS_Tick_Handler --------------------------------*/ ; void OS_Tick_Handler (void); PUBLIC OS_Tick_Handler OS_Tick_Handler: BL os_tick_irqack BL rt_systick B Sys_Switch END /*---------------------------------------------------------------------------- * end of file *---------------------------------------------------------------------------*/