/*
* 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.com/license/LICENSE.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <rtems/asm.h>
#include <rtems/score/cpu.h>
#define LR_OFFSET 8
#define CR_OFFSET 12
#define OFFSET(i) ((i) * PPC_GPR_SIZE + 16)
#define GPR14_OFFSET OFFSET(0)
#define GPR15_OFFSET OFFSET(1)
#define GPR16_OFFSET OFFSET(2)
#define GPR17_OFFSET OFFSET(3)
#define GPR18_OFFSET OFFSET(4)
#define GPR19_OFFSET OFFSET(5)
#define GPR20_OFFSET OFFSET(6)
#define GPR21_OFFSET OFFSET(7)
#define GPR22_OFFSET OFFSET(8)
#define GPR23_OFFSET OFFSET(9)
#define GPR24_OFFSET OFFSET(10)
#define GPR25_OFFSET OFFSET(11)
#define GPR26_OFFSET OFFSET(12)
#define GPR27_OFFSET OFFSET(13)
#define GPR28_OFFSET OFFSET(14)
#define GPR29_OFFSET OFFSET(15)
#define GPR30_OFFSET OFFSET(16)
#define GPR31_OFFSET OFFSET(17)
#define FRAME_SIZE \
((OFFSET(18) + CPU_STACK_ALIGNMENT - 1) & ~(CPU_STACK_ALIGNMENT - 1))
.global _CPU_Context_validate
_CPU_Context_validate:
/* Save */
stwu r1, -FRAME_SIZE(r1)
mflr r4
stw r4, LR_OFFSET(r1)
mfcr r4
stw r4, CR_OFFSET(r1)
stw r14, GPR14_OFFSET(r1)
stw r15, GPR15_OFFSET(r1)
stw r16, GPR16_OFFSET(r1)
stw r17, GPR17_OFFSET(r1)
stw r18, GPR18_OFFSET(r1)
stw r19, GPR19_OFFSET(r1)
stw r20, GPR20_OFFSET(r1)
stw r21, GPR21_OFFSET(r1)
stw r22, GPR22_OFFSET(r1)
stw r23, GPR23_OFFSET(r1)
stw r24, GPR24_OFFSET(r1)
stw r25, GPR25_OFFSET(r1)
stw r26, GPR26_OFFSET(r1)
stw r27, GPR27_OFFSET(r1)
stw r28, GPR28_OFFSET(r1)
stw r29, GPR29_OFFSET(r1)
stw r30, GPR30_OFFSET(r1)
stw r31, GPR31_OFFSET(r1)
/* Fill */
/* CR and GPR29 are equal most of the time */
addi r4, r3, 24
mtcr r4
addi r4, r3, 25
mtlr r4
addi r4, r3, 26
mtctr r4
rlwinm r4, r3, 0, 25, 2
mtxer r4
addi r0, r3, 28
/* GPR4 is used for temporary values */
addi r5, r3, 1
addi r6, r3, 2
addi r7, r3, 3
addi r8, r3, 4
addi r9, r3, 5
addi r10, r3, 6
addi r11, r3, 7
addi r12, r3, 8
addi r14, r3, 9
addi r15, r3, 10
addi r16, r3, 11
addi r17, r3, 12
addi r18, r3, 13
addi r19, r3, 14
addi r20, r3, 15
addi r21, r3, 16
addi r22, r3, 17
addi r23, r3, 18
addi r24, r3, 19
addi r25, r3, 20
addi r26, r3, 21
addi r27, r3, 22
/* GPR28 contains the GPR2 pattern */
xor r28, r2, r3
/* GPR29 and CR are equal most of the time */
addi r29, r3, 24
/* GPR30 contains the MSR pattern */
mfmsr r30
xor r30, r30, r3
/* GPR31 contains the stack pointer */
mr r31, r1
/* Check */
check:
mfcr r4
cmpw r4, r29
bne restore
addi r4, r3, 1
cmpw r4, r5
bne restore
addi r4, r3, 2
cmpw r4, r6
bne restore
addi r4, r3, 3
cmpw r4, r7
bne restore
addi r4, r3, 4
cmpw r4, r8
bne restore
addi r4, r3, 5
cmpw r4, r9
bne restore
addi r4, r3, 6
cmpw r4, r10
bne restore
addi r4, r3, 7
cmpw r4, r11
bne restore
addi r4, r3, 8
cmpw r4, r12
bne restore
lis r4, _SDA_BASE_@h
ori r4, r4, _SDA_BASE_@l
cmpw r4, r13
bne restore
addi r4, r3, 9
cmpw r4, r14
bne restore
addi r4, r3, 10
cmpw r4, r15
bne restore
addi r4, r3, 11
cmpw r4, r16
bne restore
addi r4, r3, 12
cmpw r4, r17
bne restore
addi r4, r3, 13
cmpw r4, r18
bne restore
addi r4, r3, 14
cmpw r4, r19
bne restore
addi r4, r3, 15
cmpw r4, r20
bne restore
addi r4, r3, 16
cmpw r4, r21
bne restore
addi r4, r3, 17
cmpw r4, r22
bne restore
addi r4, r3, 18
cmpw r4, r23
bne restore
addi r4, r3, 19
cmpw r4, r24
bne restore
addi r4, r3, 20
cmpw r4, r25
bne restore
addi r4, r3, 21
cmpw r4, r26
bne restore
addi r4, r3, 22
cmpw r4, r27
bne restore
xor r4, r2, r3
cmpw r4, r28
bne restore
addi r4, r3, 24
cmpw r4, r29
bne restore
mfmsr r4
xor r4, r4, r3
cmpw r4, r30
bne restore
addi r4, r3, 25
mflr r5
cmpw r4, r5
bne restore
addi r4, r3, 26
mfctr r5
cmpw r4, r5
bne restore
rlwinm r4, r3, 0, 25, 2
mfxer r5
cmpw r4, r5
bne restore
addi r4, r3, 28
cmpw r4, r0
bne restore
cmpw r31, r1
bne restore
mtcr r29
addi r5, r3, 1
b check
/* Restore */
restore:
lwz r31, GPR31_OFFSET(r1)
lwz r30, GPR30_OFFSET(r1)
lwz r29, GPR29_OFFSET(r1)
lwz r28, GPR28_OFFSET(r1)
lwz r27, GPR27_OFFSET(r1)
lwz r26, GPR26_OFFSET(r1)
lwz r25, GPR25_OFFSET(r1)
lwz r24, GPR24_OFFSET(r1)
lwz r23, GPR23_OFFSET(r1)
lwz r22, GPR22_OFFSET(r1)
lwz r21, GPR21_OFFSET(r1)
lwz r20, GPR20_OFFSET(r1)
lwz r19, GPR19_OFFSET(r1)
lwz r18, GPR18_OFFSET(r1)
lwz r17, GPR17_OFFSET(r1)
lwz r16, GPR16_OFFSET(r1)
lwz r15, GPR15_OFFSET(r1)
lwz r14, GPR14_OFFSET(r1)
lwz r4, CR_OFFSET(r1)
mtcr r4
lwz r4, LR_OFFSET(r1)
mtlr r4
addi r1, r1, FRAME_SIZE
blr