/*
* Copyright (c) 2013 embedded brains GmbH. All rights reserved.
*
* embedded brains GmbH
* Dornierstr. 4
* 82178 Puchheim
* Germany
* <rtems@embedded-brains.de>
*
* The license and distribution terms for this file may be
* found in the file LICENSE in this distribution or at
* http://www.rtems.org/license/LICENSE.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <rtems/asm.h>
#define FRAME_OFFSET_R16 0
#define FRAME_OFFSET_R17 4
#define FRAME_OFFSET_R18 8
#define FRAME_OFFSET_R19 12
#define FRAME_OFFSET_R20 16
#define FRAME_OFFSET_R21 20
#define FRAME_OFFSET_R22 24
#define FRAME_OFFSET_R23 28
#define FRAME_OFFSET_FP 32
#define FRAME_OFFSET_RA 36
#define FRAME_SIZE (FRAME_OFFSET_RA + 4)
.set noat
.section .text
.global _CPU_Context_validate
_CPU_Context_validate:
/* Save */
subi sp, sp, FRAME_SIZE
stw r16, FRAME_OFFSET_R16(sp)
stw r17, FRAME_OFFSET_R17(sp)
stw r18, FRAME_OFFSET_R18(sp)
stw r19, FRAME_OFFSET_R19(sp)
stw r20, FRAME_OFFSET_R20(sp)
stw r21, FRAME_OFFSET_R21(sp)
stw r22, FRAME_OFFSET_R22(sp)
stw r23, FRAME_OFFSET_R23(sp)
stw fp, FRAME_OFFSET_FP(sp)
stw ra, FRAME_OFFSET_RA(sp)
/* Fill */
/* AT contains the stack pointer */
mov at, sp
/* R2 is used for temporary values */
subi r3, r4, 1
addi r5, r4, 1
addi r6, r4, 2
addi r7, r4, 3
addi r8, r4, 4
addi r9, r4, 5
addi r10, r4, 6
addi r11, r4, 7
addi r12, r4, 8
addi r13, r4, 9
addi r14, r4, 10
addi r15, r4, 11
addi r16, r4, 12
addi r17, r4, 13
addi r18, r4, 14
addi r19, r4, 15
addi r20, r4, 16
addi r21, r4, 17
addi r22, r4, 18
addi r23, r4, 19
addi fp, r4, 20
addi ra, r4, 21
/* Check */
check:
bne sp, at, restore
subi r2, r4, 1
bne r2, r3, restore
addi r2, r4, 1
bne r2, r5, restore
addi r2, r4, 2
bne r2, r6, restore
addi r2, r4, 3
bne r2, r7, restore
addi r2, r4, 4
bne r2, r8, restore
addi r2, r4, 5
bne r2, r9, restore
addi r2, r4, 6
bne r2, r10, restore
addi r2, r4, 7
bne r2, r11, restore
addi r2, r4, 8
bne r2, r12, restore
addi r2, r4, 9
bne r2, r13, restore
addi r2, r4, 10
bne r2, r14, restore
addi r2, r4, 11
bne r2, r15, restore
addi r2, r4, 12
bne r2, r16, restore
addi r2, r4, 13
bne r2, r17, restore
addi r2, r4, 14
bne r2, r18, restore
addi r2, r4, 15
bne r2, r19, restore
addi r2, r4, 16
bne r2, r20, restore
addi r2, r4, 17
bne r2, r21, restore
addi r2, r4, 18
bne r2, r22, restore
addi r2, r4, 19
bne r2, r23, restore
addi r2, r4, 20
bne r2, fp, restore
addi r2, r4, 21
bne r2, ra, restore
br check
/* Restore */
restore:
ldw ra, FRAME_OFFSET_RA(sp)
ldw fp, FRAME_OFFSET_FP(sp)
ldw r23, FRAME_OFFSET_R23(sp)
ldw r22, FRAME_OFFSET_R22(sp)
ldw r21, FRAME_OFFSET_R21(sp)
ldw r20, FRAME_OFFSET_R20(sp)
ldw r19, FRAME_OFFSET_R19(sp)
ldw r18, FRAME_OFFSET_R18(sp)
ldw r17, FRAME_OFFSET_R17(sp)
ldw r16, FRAME_OFFSET_R16(sp)
addi sp, sp, FRAME_SIZE
ret
