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/*
* $Id$
*
* This file contains all assembly code for the ARM implementation
* of RTEMS.
*
* Copyright (c) 2002 by Advent Networks, Inc.
* Jay Monkman <jmonkman@adventnetworks.com>
*
* COPYRIGHT (c) 2000 Canon Research Centre France SA.
* Emmanuel Raguet, mailto:raguet@crf.canon.fr
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.OARcorp.com/rtems/license.html.
*
*/
#include <asm.h>
#include <rtems/score/cpu_asm.h>
/*
* void _CPU_Context_switch( run_context, heir_context )
* void _CPU_Context_restore( run_context, heir_context )
*
* This routine performs a normal non-FP context.
*
* R0 = run_context R1 = heir_context
*
* This function copies the current registers to where r0 points, then
* restores the ones from where r1 points.
*
*
* NOTE: The function should be able to only save/restore the registers
* that would be saved by a C function since the others have already
* been saved.
*
* It should also be able to use the stm/ldm instructions.
*
*/
.globl _CPU_Context_switch
_CPU_Context_switch:
/* FIXME: This should use load and store multiple instructions */
/* Start saving context */
str r2, [r0, #REG_R2]
str r3, [r0, #REG_R3]
str r4, [r0, #REG_R4]
str r5, [r0, #REG_R5]
str r6, [r0, #REG_R6]
str r7, [r0, #REG_R7]
str r8, [r0, #REG_R8]
str r9, [r0, #REG_R9]
str r10, [r0, #REG_R10]
str r11, [r0, #REG_R11]
str r12, [r0, #REG_R12]
str sp, [r0, #REG_SP]
str lr, [r0, #REG_PC] /* save LR at PC's location */
mrs r2, cpsr
str r2, [r0, #REG_CPSR]
/* Start restoring context */
ldr r2, [r1, #REG_CPSR]
msr cpsr, r2
ldr r2, [r1, #REG_R2]
ldr r3, [r1, #REG_R3]
ldr r4, [r1, #REG_R4]
ldr r5, [r1, #REG_R5]
ldr r6, [r1, #REG_R6]
ldr r7, [r1, #REG_R7]
ldr r8, [r1, #REG_R8]
ldr r9, [r1, #REG_R9]
ldr r10, [r1, #REG_R10]
ldr r11, [r1, #REG_R11]
ldr r12, [r1, #REG_R12]
ldr sp, [r1, #REG_SP]
ldr lr, [r1, #REG_PC]
mov pc, lr
/*
* void _CPU_Context_restore( new_context )
*
* This function copies the restores the registers from where r0 points.
* It must match _CPU_Context_switch()
*
* NOTE: The function should be able to only save/restore the registers
* that would be saved by a C function since the others have already
* been saved.
*
* It should also be able to use the stm/ldm instructions.
*
*/
.globl _CPU_Context_restore
_CPU_Context_restore:
/* FIXME: This should use load and store multiple instructions */
ldr r2, [r0, #REG_CPSR]
msr cpsr, r2
ldr r2, [r0, #REG_R2]
ldr r3, [r0, #REG_R3]
ldr r4, [r0, #REG_R4]
ldr r5, [r0, #REG_R5]
ldr r6, [r0, #REG_R6]
ldr r7, [r0, #REG_R7]
ldr r8, [r0, #REG_R8]
ldr r9, [r0, #REG_R9]
ldr r10, [r0, #REG_R10]
ldr r11, [r1, #REG_R11]
ldr r12, [r1, #REG_R12]
ldr sp, [r0, #REG_SP]
ldr lr, [r0, #REG_PC]
mov pc, lr
/* FIXME: _Exception_Handler_Undef_Swi is untested */
.globl _Exception_Handler_Undef_Swi
_Exception_Handler_Undef_Swi:
/* FIXME: This should use load and store multiple instructions */
sub r13,r13,#SIZE_REGS
str r0, [r13, #REG_R0]
str r1, [r13, #REG_R1]
str r2, [r13, #REG_R2]
str r3, [r13, #REG_R3]
str r4, [r13, #REG_R4]
str r5, [r13, #REG_R5]
str r6, [r13, #REG_R6]
str r7, [r13, #REG_R7]
str r8, [r13, #REG_R8]
str r9, [r13, #REG_R9]
str r10, [r13, #REG_R10]
str r11, [r13, #REG_R11]
str r12, [r13, #REG_R12]
str sp, [r13, #REG_SP]
str lr, [r13, #REG_LR]
mrs r0, cpsr /* read the status */
and r0, r0,#0x1f /* we keep the mode as exception number */
str r0, [r13, #REG_PC] /* we store it in a free place */
mov r0, r13 /* put frame address in r0 (C arg 1) */
ldr r1, =SWI_Handler
ldr lr, =_go_back_1
ldr pc,[r1] /* call handler */
_go_back_1:
ldr r0, [r13, #REG_R0]
ldr r1, [r13, #REG_R1]
ldr r2, [r13, #REG_R2]
ldr r3, [r13, #REG_R3]
ldr r4, [r13, #REG_R4]
ldr r5, [r13, #REG_R5]
ldr r6, [r13, #REG_R6]
ldr r7, [r13, #REG_R7]
ldr r8, [r13, #REG_R8]
ldr r9, [r13, #REG_R9]
ldr r10, [r13, #REG_R10]
ldr r11, [r13, #REG_R11]
ldr r12, [r13, #REG_R12]
ldr sp, [r13, #REG_SP]
ldr lr, [r13, #REG_LR]
add r13,r13,#SIZE_REGS
movs pc,r14 /* return */
/* FIXME: _Exception_Handler_Abort is untested */
.globl _Exception_Handler_Abort
_Exception_Handler_Abort:
/* FIXME: This should use load and store multiple instructions */
sub r13,r13,#SIZE_REGS
str r0, [r13, #REG_R0]
str r1, [r13, #REG_R1]
str r2, [r13, #REG_R2]
str r3, [r13, #REG_R3]
str r4, [r13, #REG_R4]
str r5, [r13, #REG_R5]
str r6, [r13, #REG_R6]
str r7, [r13, #REG_R7]
str r8, [r13, #REG_R8]
str r9, [r13, #REG_R9]
str r10, [r13, #REG_R10]
str sp, [r13, #REG_R11]
str lr, [r13, #REG_R12]
str lr, [r13, #REG_SP]
str lr, [r13, #REG_LR]
mrs r0, cpsr /* read the status */
and r0, r0,#0x1f /* we keep the mode as exception number */
str r0, [r13, #REG_PC] /* we store it in a free place */
mov r0, r13 /* put frame address in ro (C arg 1) */
ldr r1, =_currentExcHandler
ldr lr, =_go_back_2
ldr pc,[r1] /* call handler */
_go_back_2:
ldr r0, [r13, #REG_R0]
ldr r1, [r13, #REG_R1]
ldr r2, [r13, #REG_R2]
ldr r3, [r13, #REG_R3]
ldr r4, [r13, #REG_R4]
ldr r5, [r13, #REG_R5]
ldr r6, [r13, #REG_R6]
ldr r7, [r13, #REG_R7]
ldr r8, [r13, #REG_R8]
ldr r9, [r13, #REG_R9]
ldr r10, [r13, #REG_R10]
ldr sp, [r13, #REG_R11]
ldr lr, [r13, #REG_R12]
ldr lr, [r13, #REG_SP]
ldr lr, [r13, #REG_LR]
add r13,r13,#SIZE_REGS
subs pc,r14,#4 /* return */
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