arch/arm/mach-msm/msm_watchdog_asm.S

/* Copyright (c) 2012, The Linux Foundation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 and
 * only version 2 as published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 */

#include <linux/linkage.h>
#include <asm/assembler.h>

#define VERSION_ID 0x1
#define MAGIC 0xDEAD0000 | VERSION_ID

	.text

	.align 3

ENTRY(msm_wdog_fiq_start)
	mov	sp, r8		@get stack
	ldr	r8, Ldump_cpu_ctx
	@ store magic to indicate a valid dump
	ldr	r9, Lmagic
	str	r9, [r8], #4
	@ get the current cpsr
	mrs	r9, cpsr
	str	r9, [r8],#4
	@ get the USR r0-r7
	stmia	r8!, {r0-r7}
	mov	r4, r8
	mov	r5, #PSR_I_BIT | PSR_F_BIT | SYSTEM_MODE
	msr	cpsr_c, r5	@ select SYSTEM mode
	stmia	r4!, {r8-r14}
	mov	r5, #PSR_I_BIT | PSR_F_BIT | IRQ_MODE
	msr	cpsr_c, r5	@ select IRQ mode
	mrs	r5, spsr
	str	r5, [r4], #4
	stmia	r4!, {r13-r14}
	mov	r5, #PSR_I_BIT | PSR_F_BIT | SVC_MODE
	msr	cpsr_c, r5	@ select SVC mode
	mrs	r5, spsr
	str	r5, [r4], #4
	stmia	r4!, {r13-r14}
	mov	r5, #PSR_I_BIT | PSR_F_BIT | ABT_MODE
	msr	cpsr_c, r5	@ select ABT mode
	mrs	r5, spsr
	str	r5, [r4], #4
	stmia	r4!, {r13-r14}
	mov	r5, #PSR_I_BIT | PSR_F_BIT | UND_MODE
	msr	cpsr_c, r5	@ select UND mode
	mrs	r5, spsr
	str	r5, [r4], #4
	stmia	r4!, {r13-r14}
	mov	r5, #PSR_I_BIT | PSR_F_BIT | FIQ_MODE
	msr	cpsr_c, r5	@ select FIQ mode
	mrs	r5, spsr
	str	r5, [r4], #4
	stmia	r4!, {r8-r14}
	dsb
	mov	r5, #PSR_F_BIT | SVC_MODE
	msr	cpsr_c, r5	@ select SVC mode
	ldr	r2, Lwatchdog_bark_fin
	blx	r2
Ldump_cpu_ctx:
	.word	msm_dump_cpu_ctx
Lmagic:
	.word	MAGIC
Lwatchdog_bark_fin:
	.word	msm_wdog_bark_fin
ENTRY(msm_wdog_fiq_length)
	.word	. - msm_wdog_fiq_start

/* setup the stack */
ENTRY(msm_wdog_fiq_setup)
	mrs	r3, cpsr
	msr	cpsr_c, #(FIQ_MODE | PSR_I_BIT | PSR_F_BIT)
	mov	r8, r0
	msr	cpsr_c, r3
	bx	lr