Rtos code cntains bug possible incompatability with I2C
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Diff: rtx_ca/ARM/HAL_CA9.c
- Revision:
- 48:e9a2c7cb57a4
diff -r 65a1b2fc9a51 -r e9a2c7cb57a4 rtx_ca/ARM/HAL_CA9.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/rtx_ca/ARM/HAL_CA9.c Thu Nov 06 11:00:33 2014 +0000 @@ -0,0 +1,416 @@ +/*---------------------------------------------------------------------------- + * 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. + *---------------------------------------------------------------------------*/ + +#include "rt_TypeDef.h" +#include "RTX_Config.h" +#include "rt_System.h" +#include "rt_Task.h" +#include "rt_List.h" +#include "rt_MemBox.h" +#include "rt_HAL_CA.h" + + +/*---------------------------------------------------------------------------- + * Functions + *---------------------------------------------------------------------------*/ + +//For A-class, set USR/SYS stack +__asm void rt_set_PSP (U32 stack) { + 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) { + 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) { + /* Function wrapper for Unprivileged/Privileged mode. */ + ARM + + LDR R12,=__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) { + /* Function wrapper for Unprivileged/Privileged mode. */ + ARM + + LDR R12,=__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) { + PRESERVE8 + ARM + + IMPORT rt_tsk_lock + IMPORT rt_tsk_unlock + IMPORT SVC_Count + IMPORT SVC_Table + IMPORT rt_stk_check + IMPORT FPUEnable + +Mode_SVC EQU 0x13 + + SRSFD 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,=__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,=__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) { + ARM + + IMPORT rt_tsk_lock + IMPORT 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, =__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 __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) { + ARM + + IMPORT rt_tsk_lock + IMPORT IRQNestLevel + + 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, =__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 __cpp(os_tick_irqack) + BLX __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 + + +/*---------------------------------------------------------------------------- + * end of file + *---------------------------------------------------------------------------*/