linux/arch/arm/mach-s3c24xx/sleep.S

71 lines
1.5 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0+ */
/*
* 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
*/
#include <linux/linkage.h>
#include <linux/serial_s3c.h>
#include <asm/assembler.h>
#include <mach/hardware.h>
#include <mach/map.h>
#include <mach/regs-gpio.h>
#include <mach/regs-clock.h>
/*
* S3C24XX_DEBUG_RESUME is dangerous if your bootloader does not
* reset the UART configuration, only enable if you really need this!
*/
//#define S3C24XX_DEBUG_RESUME
.text
/* sleep magic, to allow the bootloader to check for an valid
* image to resume to. Must be the first word before the
* s3c_cpu_resume entry.
*/
.word 0x2bedf00d
/* s3c_cpu_resume
*
* resume code entry for bootloader to call
*/
ENTRY(s3c_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 S3C24XX_DEBUG_RESUME
mov r3, #'L'
strb r3, [ r2, #S3C2410_UTXH ]
1001:
ldrb r14, [ r3, #S3C2410_UTRSTAT ]
tst r14, #S3C2410_UTRSTAT_TXE
beq 1001b
#endif /* S3C24XX_DEBUG_RESUME */
b cpu_resume