Official mbed Real Time Operating System based on the RTX implementation of the CMSIS-RTOS API open standard.
Dependents: denki-yohou_b TestY201 Network-RTOS NTPClient_HelloWorld ... more
Deprecated
This is the mbed 2 rtos library. mbed OS 5 integrates the mbed library with mbed-rtos. With this, we have provided thread safety for all mbed APIs. If you'd like to learn about using mbed OS 5, please see the docs.
Diff: rtx/TARGET_CORTEX_A/TOOLCHAIN_GCC/HAL_CA9.s
- Revision:
- 67:63988a2238f7
- Child:
- 68:d3d0e710b443
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/rtx/TARGET_CORTEX_A/TOOLCHAIN_GCC/HAL_CA9.s Fri Feb 27 10:00:40 2015 +0000 @@ -0,0 +1,474 @@ +/*---------------------------------------------------------------------------- + * RL-ARM - RTX + *---------------------------------------------------------------------------- + * Name: HAL_CA9.c + * Purpose: Hardware Abstraction Layer for Cortex-A9 + * Rev.: 3 Sept 2013 + *---------------------------------------------------------------------------- + * + * Copyright (c) 2012 - 2013 ARM Limited + * 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. + *---------------------------------------------------------------------------*/ + + .global rt_set_PSP + .global rt_get_PSP + .global _alloc_box + .global _free_box + .global PendSV_Handler + .global OS_Tick_Handler + + .EQU CPSR_T_BIT, 0x20 + .EQU CPSR_I_BIT, 0x80 + .EQU CPSR_F_BIT, 0x40 + + .EQU MODE_USR, 0x10 + .EQU MODE_FIQ, 0x11 + .EQU MODE_IRQ, 0x12 + .EQU MODE_SVC, 0x13 + .EQU MODE_ABT, 0x17 + .EQU MODE_UND, 0x1B + .EQU MODE_SYS, 0x1F + + .EQU TCB_TID, 3 /* 'task id' offset */ + .EQU TCB_STACKF, 32 /* 'stack_frame' offset */ + .EQU TCB_TSTACK, 36 /* 'tsk_stack' offset */ + + .extern rt_alloc_box + .extern os_tsk + .extern GICInterface_BASE + .extern rt_pop_req + .extern os_tick_irqack + .extern rt_systick + +/*---------------------------------------------------------------------------- + * Functions + *---------------------------------------------------------------------------*/ + .text +@ For A-class, set USR/SYS stack +@ __asm void rt_set_PSP (U32 stack) { +rt_set_PSP: + .arm + + MRS R1, CPSR + CPS #MODE_SYS @no effect in USR mode + ISB + MOV SP, R0 + MSR CPSR_c, R1 @no effect in USR mode + ISB + BX LR + +@ } + +@ For A-class, get USR/SYS stack +@ __asm U32 rt_get_PSP (void) { +rt_get_PSP: + .arm + + MRS R1, CPSR + CPS #MODE_SYS @no effect in USR mode + ISB + MOV R0, SP + MSR CPSR_c, R1 @no effect in USR mode + ISB + BX LR + +@ } + +/*--------------------------- _alloc_box ------------------------------------*/ +@ __asm void *_alloc_box (void *box_mem) { +_alloc_box: + /* Function wrapper for Unprivileged/Privileged mode. */ + .arm + + LDR R12,=rt_alloc_box @ __cpp(rt_alloc_box) + MRS R2, CPSR + LSLS R2, #28 + BXNE R12 + SVC 0 + BX LR +@ } + + +/*--------------------------- _free_box -------------------------------------*/ +@ __asm int _free_box (void *box_mem, void *box) { +_free_box: + /* Function wrapper for Unprivileged/Privileged mode. */ + .arm + + LDR R12,=rt_free_box @ __cpp(rt_free_box) + MRS R2, CPSR + LSLS R2, #28 + BXNE R12 + SVC 0 + BX LR + +@ } + +/*-------------------------- SVC_Handler -----------------------------------*/ + +@ #pragma push +@ #pragma arm +@ __asm void SVC_Handler (void) { + + .type SVC_Handler, %function + .global SVC_Handler +SVC_Handler: +@ PRESERVE8 + .arm + .extern rt_tsk_lock + .extern rt_tsk_unlock + .extern SVC_Count + .extern SVC_Table + .extern rt_stk_check + .extern FPUEnable + + .EQU Mode_SVC, 0x13 + + SRSDB SP!, #Mode_SVC @ Push LR_SVC and SPRS_SVC onto SVC mode stack + PUSH {R4} @ Push R4 so we can use it as a temp + + + MRS R4,SPSR @ Get SPSR + TST R4,#CPSR_T_BIT @ Check Thumb Bit + LDRNEH R4,[LR,#-2] @ Thumb: Load Halfword + BICNE R4,R4,#0xFF00 @ Extract SVC Number + LDREQ R4,[LR,#-4] @ ARM: Load Word + BICEQ R4,R4,#0xFF000000 @ Extract SVC Number + + /* Lock out systick and re-enable interrupts */ + PUSH {R0-R3,R12,LR} + + AND R12, SP, #4 @ Ensure stack is 8-byte aligned + SUB SP, SP, R12 @ Adjust stack + PUSH {R12, LR} @ Store stack adjustment and dummy LR to SVC stack + + BLX rt_tsk_lock + CPSIE i + + POP {R12, LR} @ Get stack adjustment & discard dummy LR + ADD SP, SP, R12 @ Unadjust stack + + POP {R0-R3,R12,LR} + + CMP R4,#0 + BNE SVC_User + + MRS R4,SPSR + PUSH {R4} @ Push R4 so we can use it as a temp + AND R4, SP, #4 @ Ensure stack is 8-byte aligned + SUB SP, SP, R4 @ Adjust stack + PUSH {R4, LR} @ Store stack adjustment and dummy LR + BLX R12 + POP {R4, LR} @ Get stack adjustment & discard dummy LR + ADD SP, SP, R4 @ Unadjust stack + POP {R4} @ Restore R4 + MSR SPSR_cxsf,R4 + + /* Here we will be in SVC mode (even if coming in from PendSV_Handler or OS_Tick_Handler) */ +Sys_Switch: + LDR LR,=os_tsk @ __cpp(&os_tsk) + LDM LR,{R4,LR} @ os_tsk.run, os_tsk.new + CMP R4,LR + BNE switching + + PUSH {R0-R3,R12,LR} + + AND R12, SP, #4 @ Ensure stack is 8-byte aligned + SUB SP, SP, R12 @ Adjust stack + PUSH {R12, LR} @ Store stack adjustment and dummy LR to SVC stack + + CPSID i + BLX rt_tsk_unlock + + POP {R12, LR} @ Get stack adjustment & discard dummy LR + ADD SP, SP, R12 @ Unadjust stack + + POP {R0-R3,R12,LR} + POP {R4} + RFEFD SP! @ Return from exception, no task switch + +switching: + CLREX + CMP R4,#0 + ADDEQ SP,SP,#12 @ Original R4, LR & SPSR do not need to be popped when we are paging in a different task + BEQ SVC_Next @ Runtask deleted? + + + PUSH {R8-R11} @ R4 and LR already stacked + MOV R10,R4 @ Preserve os_tsk.run + MOV R11,LR @ Preserve os_tsk.new + + ADD R8,SP,#16 @ Unstack R4,LR + LDMIA R8,{R4,LR} + + SUB SP,SP,#4 @ Make space on the stack for the next instn + STMIA SP,{SP}^ @ Put User SP onto stack + POP {R8} @ Pop User SP into R8 + + MRS R9,SPSR + STMDB R8!,{R9} @ User CPSR + STMDB R8!,{LR} @ User PC + STMDB R8,{LR}^ @ User LR + SUB R8,R8,#4 @ No writeback for store of User LR + STMDB R8!,{R0-R3,R12} @ User R0-R3,R12 + MOV R3,R10 @ os_tsk.run + MOV LR,R11 @ os_tsk.new + POP {R9-R12} + ADD SP,SP,#12 @ Fix up SP for unstack of R4, LR & SPSR + STMDB R8!,{R4-R7,R9-R12} @ User R4-R11 + + @ If applicable, stack VFP state + MRC p15,0,R1,c1,c0,2 @ VFP/NEON access enabled? (CPACR) + AND R2,R1,#0x00F00000 + CMP R2,#0x00F00000 + BNE no_outgoing_vfp + VMRS R2,FPSCR + STMDB R8!,{R2,R4} @ Push FPSCR, maintain 8-byte alignment + VSTMDB R8!,{S0-S31} + LDRB R2,[R3,#TCB_STACKF] @ Record in TCB that VFP state is stacked + ORR R2,#2 + STRB R2,[R3,#TCB_STACKF] + +no_outgoing_vfp: + STR R8,[R3,#TCB_TSTACK] + MOV R4,LR + + PUSH {R4} @ Push R4 so we can use it as a temp + AND R4, SP, #4 @ Ensure stack is 8-byte aligned + SUB SP, SP, R4 @ Adjust stack + PUSH {R4, LR} @ Store stack adjustment and dummy LR to SVC stack + + BLX rt_stk_check + + POP {R4, LR} @ Get stack adjustment & discard dummy LR + ADD SP, SP, R4 @ Unadjust stack + POP {R4} @ Restore R4 + + MOV LR,R4 + +SVC_Next: @ R4 == os_tsk.run, LR == os_tsk.new, R0-R3, R5-R12 corruptible + LDR R1,=os_tsk @ __cpp(&os_tsk), os_tsk.run = os_tsk.new + STR LR,[R1] + LDRB R1,[LR,#TCB_TID] @ os_tsk.run->task_id + LSL R1,#8 @ Store PROCID + MCR p15,0,R1,c13,c0,1 @ Write CONTEXTIDR + + LDR R0,[LR,#TCB_TSTACK] @ os_tsk.run->tsk_stack + + @ Does incoming task have VFP state in stack? + LDRB R3,[LR,#TCB_STACKF] + TST R3,#0x2 + MRC p15,0,R1,c1,c0,2 @ Read CPACR + ANDEQ R1,R1,#0xFF0FFFFF @ Disable VFP access if incoming task does not have stacked VFP state + ORRNE R1,R1,#0x00F00000 @ Enable VFP access if incoming task does have stacked VFP state + MCR p15,0,R1,c1,c0,2 @ Write CPACR + BEQ no_incoming_vfp + ISB @ We only need the sync if we enabled, otherwise we will context switch before next VFP instruction anyway + VLDMIA R0!,{S0-S31} + LDR R2,[R0] + VMSR FPSCR,R2 + ADD R0,R0,#8 + +no_incoming_vfp: + LDR R1,[R0,#60] @ Restore User CPSR + MSR SPSR_cxsf,R1 + LDMIA R0!,{R4-R11} @ Restore User R4-R11 + ADD R0,R0,#4 @ Restore User R1-R3,R12 + LDMIA R0!,{R1-R3,R12} + LDMIA R0,{LR}^ @ Restore User LR + ADD R0,R0,#4 @ No writeback for load to user LR + LDMIA R0!,{LR} @ Restore User PC + ADD R0,R0,#4 @ Correct User SP for unstacked user CPSR + + PUSH {R0} @ Push R0 onto stack + LDMIA SP,{SP}^ @ Get R0 off stack into User SP + ADD SP,SP,#4 @ Put SP back + + LDR R0,[R0,#-32] @ Restore R0 + + PUSH {R0-R3,R12,LR} + + AND R12, SP, #4 @ Ensure stack is 8-byte aligned + SUB SP, SP, R12 @ Adjust stack + PUSH {R12, LR} @ Store stack adjustment and dummy LR to SVC stack + + CPSID i + BLX rt_tsk_unlock + + POP {R12, LR} @ Get stack adjustment & discard dummy LR + ADD SP, SP, R12 @ Unadjust stack + + POP {R0-R3,R12,LR} + + MOVS PC,LR @ Return from exception + + + /*------------------- User SVC -------------------------------*/ + +SVC_User: + LDR R12,=SVC_Count + LDR R12,[R12] + CMP R4,R12 @ Check for overflow + BHI SVC_Done + + LDR R12,=SVC_Table-4 + LDR R12,[R12,R4,LSL #2] @ Load SVC Function Address + MRS R4,SPSR @ Save SPSR + PUSH {R4} @ Push R4 so we can use it as a temp + AND R4, SP, #4 @ Ensure stack is 8-byte aligned + SUB SP, SP, R4 @ Adjust stack + PUSH {R4, LR} @ Store stack adjustment and dummy LR + BLX R12 @ Call SVC Function + POP {R4, LR} @ Get stack adjustment & discard dummy LR + ADD SP, SP, R4 @ Unadjust stack + POP {R4} @ Restore R4 + MSR SPSR_cxsf,R4 @ Restore SPSR + +SVC_Done: + PUSH {R0-R3,R12,LR} + + PUSH {R4} @ Push R4 so we can use it as a temp + AND R4, SP, #4 @ Ensure stack is 8-byte aligned + SUB SP, SP, R4 @ Adjust stack + PUSH {R4, LR} @ Store stack adjustment and dummy LR + + CPSID i + BLX rt_tsk_unlock + + POP {R4, LR} @ Get stack adjustment & discard dummy LR + ADD SP, SP, R4 @ Unadjust stack + POP {R4} @ Restore R4 + + POP {R0-R3,R12,LR} + POP {R4} + RFEFD SP! @ Return from exception + +@ } + +@ #pragma pop + + +@ #pragma push +@ #pragma arm +@ __asm void PendSV_Handler (U32 IRQn) { +PendSV_Handler: + .arm + + .extern rt_tsk_lock + .extern IRQNestLevel + + ADD SP,SP,#8 @ fix up stack pointer (R0 has been pushed and will never be popped, R1 was pushed for stack alignment) + + @ Disable systick interrupts, then write EOIR. We want interrupts disabled before we enter the context switcher. + PUSH {R0, R1} + BLX rt_tsk_lock + POP {R0, R1} + LDR R1, =GICInterface_BASE @ __cpp(&GICInterface_BASE) + LDR R1, [R1, #0] + STR R0, [R1, #0x10] + + LDR R0, =IRQNestLevel @ Get address of nesting counter + LDR R1, [R0] + SUB R1, R1, #1 @ Decrement nesting counter + STR R1, [R0] + + BLX rt_pop_req @ __cpp(rt_pop_req) + + POP {R1, LR} @ Get stack adjustment & discard dummy LR + ADD SP, SP, R1 @ Unadjust stack + + LDR R0,[SP,#24] + MSR SPSR_cxsf,R0 + POP {R0-R3,R12} @ Leave SPSR & LR on the stack + PUSH {R4} + B Sys_Switch +@ } +@ #pragma pop + +@ #pragma push +@ #pragma arm +@ __asm void OS_Tick_Handler (U32 IRQn) { +OS_Tick_Handler: + .arm + + ADD SP,SP,#8 @ fix up stack pointer (R0 has been pushed and will never be popped, R1 was pushed for stack alignment) + + PUSH {R0, R1} + BLX rt_tsk_lock + POP {R0, R1} + LDR R1, =GICInterface_BASE @ __cpp(&GICInterface_BASE) + LDR R1, [R1, #0] + STR R0, [R1, #0x10] + + LDR R0, =IRQNestLevel @ Get address of nesting counter + LDR R1, [R0] + SUB R1, R1, #1 @ Decrement nesting counter + STR R1, [R0] + + BLX os_tick_irqack @ __cpp(os_tick_irqack) + BLX rt_systick @ __cpp(rt_systick) + + POP {R1, LR} @ Get stack adjustment & discard dummy LR + ADD SP, SP, R1 @ Unadjust stack + + LDR R0,[SP,#24] + MSR SPSR_cxsf,R0 + POP {R0-R3,R12} @ Leave SPSR & LR on the stack + PUSH {R4} + B Sys_Switch +@ } +@ #pragma pop + + .global __set_PSP +@ __STATIC_ASM void __set_PSP(uint32_t topOfProcStack) +@ { +__set_PSP: +@ PRESERVE8 + .arm + + BIC R0, R0, #7 @ensure stack is 8-byte aligned + MRS R1, CPSR + CPS #MODE_SYS @no effect in USR mode + MOV SP, R0 + MSR CPSR_c, R1 @no effect in USR mode + ISB + BX LR + +@ } + + .global __set_CPS_USR +@ __STATIC_ASM void __set_CPS_USR(void) +@ { +__set_CPS_USR: + .arm + + CPS #MODE_USR + BX LR +@ } + + .END +/*---------------------------------------------------------------------------- + * end of file + *---------------------------------------------------------------------------*/