/* linux/arch/arm/plat-s3c24xx/sleep.S * * Copyright (c) 2004 Simtec Electronics *	Ben Dooks <ben@simtec.co.uk> * * 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>/* CONFIG_DEBUG_RESUME is dangerous if your bootloader does not * reset the UART configuration, only enable if you really need this!*///#define CONFIG_DEBUG_RESUME	.text	/* s3c2410_cpu_save	 *	 * save enough of the CPU state to allow us to re-start	 * pm.c code. as we store items like the sp/lr, we will	 * end up returning from this function when the cpu resumes	 * so the return value is set to mark this.	 *	 * This arangement means we avoid having to flush the cache	 * from this code.	 *	 * entry:	 *	r0 = pointer to save block	 *	 * exit:	 *	r0 = 0 => we stored everything	 *	     1 => resumed from sleep	*/ENTRY(s3c2410_cpu_save)	stmfd	sp!, { r4 - r12, lr }	@@ store co-processor registers	mrc	p15, 0, r4, c13, c0, 0	@ PID	mrc	p15, 0, r5, c3, c0, 0	@ Domain ID	mrc	p15, 0, r6, c2, c0, 0	@ translation table base address	mrc	p15, 0, r7, c1, c0, 0	@ control register	stmia	r0, { r4 - r13 }	mov	r0, #0	ldmfd	sp, { r4 - r12, pc }	@@ return to the caller, after having the MMU	@@ turned on, this restores the last bits from the	@@ stackresume_with_mmu:	mov	r0, #1	ldmfd	sp!, { r4 - r12, pc }	.ltorg	@@ the next bits sit in the .data segment, even though they	@@ happen to be code... the s3c2410_sleep_save_phys needs to be	@@ accessed by the resume code before it can restore the MMU.	@@ This means that the variable has to be close enough for the	@@ code to read it... since the .text segment needs to be RO,	@@ the data segment can be the only place to put this code.	.data	.global	s3c2410_sleep_save_physs3c2410_sleep_save_phys:	.word	0	/* sleep magic, to allow the bootloader to check for an valid	 * image to resume to. Must be the first word before the	 * s3c2410_cpu_resume entry.	*/	.word	0x2bedf00d	/* s3c2410_cpu_resume	 *	 * resume code entry for bootloader to call	 *	 * we must put this code here in the data segment as we have no	 * other way of restoring the stack pointer after sleep, and we	 * must not write to the code segment (code is read-only)	*/ENTRY(s3c2410_cpu_resume)	mov	r0, #PSR_I_BIT | PSR_F_BIT | SVC_MODE	msr	cpsr_c, r0	@@ load UART to allow us to print the two characters for	@@ resume debug	mov	r2, #S3C24XX_PA_UART & 0xff000000	orr	r2, r2, #S3C24XX_PA_UART & 0xff000#if 0	/* SMDK2440 LED set */	mov	r14, #S3C24XX_PA_GPIO	ldr	r12, [ r14, #0x54 ]	bic	r12, r12, #3<<4	orr	r12, r12, #1<<7	str	r12, [ r14, #0x54 ]#endif#ifdef CONFIG_DEBUG_RESUME	mov	r3, #'L'	strb	r3, [ r2, #S3C2410_UTXH ]1001:	ldrb	r14, [ r3, #S3C2410_UTRSTAT ]	tst	r14, #S3C2410_UTRSTAT_TXE	beq	1001b#endif /* CONFIG_DEBUG_RESUME */	mov	r1, #0	mcr	p15, 0, r1, c8, c7, 0		@@ invalidate I & D TLBs	mcr	p15, 0, r1, c7, c7, 0		@@ invalidate I & D caches	ldr	r0, s3c2410_sleep_save_phys	@ address of restore block	ldmia	r0, { r4 - r13 }	mcr	p15, 0, r4, c13, c0, 0		@ PID	mcr	p15, 0, r5, c3, c0, 0		@ Domain ID	mcr	p15, 0, r6, c2, c0, 0		@ translation table base#ifdef CONFIG_DEBUG_RESUME	mov	r3, #'R'	strb	r3, [ r2, #S3C2410_UTXH ]#endif	ldr	r2, =resume_with_mmu	mcr	p15, 0, r7, c1, c0, 0		@ turn on MMU, etc	nop					@ second-to-last before mmu	mov	pc, r2				@ go back to virtual address	.ltorg