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/*----------------------------------------------------------------------------
* CMSIS-RTOS - RTX
*----------------------------------------------------------------------------
* Name: HAL_CM0.S
* Purpose: Hardware Abstraction Layer for Cortex-M0
* Rev.: V4.70
*----------------------------------------------------------------------------
*
* Copyright (c) 1999-2009 KEIL, 2009-2013 ARM Germany GmbH
* All rights reserved.
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - Neither the name of ARM nor the names of its contributors may be used
* to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDERS AND CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*---------------------------------------------------------------------------*/
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 -------------------------------------*/
; int _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.new */
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.new */
LDR R0,[R2,#TCB_TSTACK] /* os_tsk.new->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.new */
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.new */
LDR R0,[R2,#TCB_TSTACK] /* os_tsk.new->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
*---------------------------------------------------------------------------*/
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