1/* SPDX-License-Identifier: GPL-2.0 */
2/* linux/arch/arm/plat-s3c64xx/sleep.S
3 *
4 * Copyright 2008 Openmoko, Inc.
5 * Copyright 2008 Simtec Electronics
6 *	Ben Dooks <ben@simtec.co.uk>
7 *	http://armlinux.simtec.co.uk/
8 *
9 * S3C64XX CPU sleep code
10 */
11
12#include <linux/linkage.h>
13#include <asm/assembler.h>
14#include "map.h"
15
16#undef S3C64XX_VA_GPIO
17#define S3C64XX_VA_GPIO (0x0)
18
19#include "regs-gpio.h"
20
21#define LL_UART (S3C_PA_UART + (0x400 * CONFIG_S3C_LOWLEVEL_UART_PORT))
22
23	.text
24
25	/* Sleep magic, the word before the resume entry point so that the
26	 * bootloader can check for a resumeable image. */
27
28	.word	0x2bedf00d
29
30	/* s3c_cpu_reusme
31	 *
32	 * This is the entry point, stored by whatever method the bootloader
33	 * requires to get the kernel runnign again. This code expects to be
34	 * entered with no caches live and the MMU disabled. It will then
35	 * restore the MMU and other basic CP registers saved and restart
36	 * the kernel C code to finish the resume code.
37	*/
38
39ENTRY(s3c_cpu_resume)
40	msr	cpsr_c, #PSR_I_BIT | PSR_F_BIT | SVC_MODE
41	ldr	r2, =LL_UART		/* for debug */
42
43#ifdef CONFIG_S3C_PM_DEBUG_LED_SMDK
44
45#define S3C64XX_GPNCON			(S3C64XX_GPN_BASE + 0x00)
46#define S3C64XX_GPNDAT			(S3C64XX_GPN_BASE + 0x04)
47
48#define S3C64XX_GPN_CONMASK(__gpio)	(0x3 << ((__gpio) * 2))
49#define S3C64XX_GPN_OUTPUT(__gpio)	(0x1 << ((__gpio) * 2))
50
51	/* Initialise the GPIO state if we are debugging via the SMDK LEDs,
52	 * as the uboot version supplied resets these to inputs during the
53	 * resume checks.
54	*/
55
56	ldr	r3, =S3C64XX_PA_GPIO
57	ldr	r0, [ r3, #S3C64XX_GPNCON ]
58	bic	r0, r0, #(S3C64XX_GPN_CONMASK(12) | S3C64XX_GPN_CONMASK(13) | \
59			  S3C64XX_GPN_CONMASK(14) | S3C64XX_GPN_CONMASK(15))
60	orr	r0, r0, #(S3C64XX_GPN_OUTPUT(12) | S3C64XX_GPN_OUTPUT(13) | \
61			  S3C64XX_GPN_OUTPUT(14) | S3C64XX_GPN_OUTPUT(15))
62	str	r0, [ r3, #S3C64XX_GPNCON ]
63
64	ldr	r0, [ r3, #S3C64XX_GPNDAT ]
65	bic	r0, r0, #0xf << 12			@ GPN12..15
66	orr	r0, r0, #1 << 15			@ GPN15
67	str	r0, [ r3, #S3C64XX_GPNDAT ]
68#endif
69	b	cpu_resume
70