sleep.s

linux 内核源代码

/* linux/arch/arm/mach-s3c2410/sleep.S
 *
 * Copyright (c) 2004 Simtec Electronics
 *	Ben Dooks <[e-mail]>
 *
 * S3C2410 Power Manager (Suspend-To-RAM) support
 *
 * Based on PXA/SA1100 sleep code by:
 *	Nicolas Pitre, (c) 2002 Monta Vista Software Inc
 *	Cliff Brake, (c) 2001
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * 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.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

#include <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/hardware.h>
#include <asm/arch/map.h>

#include <asm/arch/regs-gpio.h>
#include <asm/arch/regs-clock.h>
#include <asm/arch/regs-mem.h>
#include <asm/plat-s3c/regs-serial.h>

	/* s3c2410_cpu_suspend
	 *
	 * put the cpu into sleep mode
	*/

ENTRY(s3c2410_cpu_suspend)
	@@ prepare cpu to sleep

	ldr	r4, =S3C2410_REFRESH
	ldr	r5, =S3C24XX_MISCCR
	ldr	r6, =S3C2410_CLKCON
	ldr	r7, [ r4 ]		@ get REFRESH (and ensure in TLB)
	ldr	r8, [ r5 ]		@ get MISCCR (and ensure in TLB)
	ldr	r9, [ r6 ]		@ get CLKCON (and ensure in TLB)

	orr	r7, r7, #S3C2410_REFRESH_SELF	@ SDRAM sleep command
	orr	r8, r8, #S3C2410_MISCCR_SDSLEEP @ SDRAM power-down signals
	orr	r9, r9, #S3C2410_CLKCON_POWER	@ power down command

	teq	pc, #0			@ first as a trial-run to load cache
	bl	s3c2410_do_sleep
	teq	r0, r0			@ now do it for real
	b	s3c2410_do_sleep	@

	@@ align next bit of code to cache line
	.align	5
s3c2410_do_sleep:
	streq	r7, [ r4 ]			@ SDRAM sleep command
	streq	r8, [ r5 ]			@ SDRAM power-down config
	streq	r9, [ r6 ]			@ CPU sleep
1:	beq	1b
	mov	pc, r14