1/* SPDX-License-Identifier: GPL-2.0+ */ 2/* 3 * Copyright (c) 2004 Simtec Electronics 4 * Ben Dooks <ben@simtec.co.uk> 5 * 6 * S3C2410 Power Manager (Suspend-To-RAM) support 7 * 8 * Based on PXA/SA1100 sleep code by: 9 * Nicolas Pitre, (c) 2002 Monta Vista Software Inc 10 * Cliff Brake, (c) 2001 11 */ 12 13#include <linux/linkage.h> 14#include <linux/serial_s3c.h> 15#include <asm/assembler.h> 16#include "map.h" 17 18#include "regs-gpio.h" 19#include "regs-clock.h" 20 21/* 22 * S3C24XX_DEBUG_RESUME is dangerous if your bootloader does not 23 * reset the UART configuration, only enable if you really need this! 24 */ 25//#define S3C24XX_DEBUG_RESUME 26 27 .text 28 29 /* sleep magic, to allow the bootloader to check for an valid 30 * image to resume to. Must be the first word before the 31 * s3c_cpu_resume entry. 32 */ 33 34 .word 0x2bedf00d 35 36 /* s3c_cpu_resume 37 * 38 * resume code entry for bootloader to call 39 */ 40 41ENTRY(s3c_cpu_resume) 42 mov r0, #PSR_I_BIT | PSR_F_BIT | SVC_MODE 43 msr cpsr_c, r0 44 45 @@ load UART to allow us to print the two characters for 46 @@ resume debug 47 48 mov r2, #S3C24XX_PA_UART & 0xff000000 49 orr r2, r2, #S3C24XX_PA_UART & 0xff000 50 51#if 0 52 /* SMDK2440 LED set */ 53 mov r14, #S3C24XX_PA_GPIO 54 ldr r12, [ r14, #0x54 ] 55 bic r12, r12, #3<<4 56 orr r12, r12, #1<<7 57 str r12, [ r14, #0x54 ] 58#endif 59 60#ifdef S3C24XX_DEBUG_RESUME 61 mov r3, #'L' 62 strb r3, [ r2, #S3C2410_UTXH ] 631001: 64 ldrb r14, [ r3, #S3C2410_UTRSTAT ] 65 tst r14, #S3C2410_UTRSTAT_TXE 66 beq 1001b 67#endif /* S3C24XX_DEBUG_RESUME */ 68 69 b cpu_resume 70