1/*
2 * SA1100 Power Management Routines
3 *
4 * Copyright (c) 2001 Cliff Brake <cbrake@accelent.com>
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License.
8 *
9 * History:
10 *
11 * 2001-02-06: Cliff Brake Initial code
12 *
13 * 2001-02-25: Sukjae Cho <sjcho@east.isi.edu> &
14 * Chester Kuo <chester@linux.org.tw>
15 * Save more value for the resume function! Support
16 * Bitsy/Assabet/Freebird board
17 *
18 * 2001-08-29: Nicolas Pitre <nico@fluxnic.net>
19 * Cleaned up, pushed platform dependent stuff
20 * in the platform specific files.
21 *
22 * 2002-05-27: Nicolas Pitre Killed sleep.h and the kmalloced save array.
23 * Storage is local on the stack now.
24 */
25#include <linux/init.h>
26#include <linux/io.h>
27#include <linux/suspend.h>
28#include <linux/errno.h>
29#include <linux/time.h>
30
31#include <mach/hardware.h>
32#include <asm/page.h>
33#include <asm/suspend.h>
34#include <asm/mach/time.h>
35
36#include "generic.h"
37
38extern int sa1100_finish_suspend(unsigned long);
39
40#define SAVE(x) sleep_save[SLEEP_SAVE_##x] = x
41#define RESTORE(x) x = sleep_save[SLEEP_SAVE_##x]
42
43/*
44 * List of global SA11x0 peripheral registers to preserve.
45 * More ones like CP and general purpose register values are preserved
46 * on the stack and then the stack pointer is stored last in sleep.S.
47 */
48enum { SLEEP_SAVE_GPDR, SLEEP_SAVE_GAFR,
49 SLEEP_SAVE_PPDR, SLEEP_SAVE_PPSR, SLEEP_SAVE_PPAR, SLEEP_SAVE_PSDR,
50
51 SLEEP_SAVE_Ser1SDCR0,
52
53 SLEEP_SAVE_COUNT
54};
55
56
57static int sa11x0_pm_enter(suspend_state_t state)
58{
59 unsigned long gpio, sleep_save[SLEEP_SAVE_COUNT];
60
61 gpio = GPLR;
62
63 /* save vital registers */
64 SAVE(GPDR);
65 SAVE(GAFR);
66
67 SAVE(PPDR);
68 SAVE(PPSR);
69 SAVE(PPAR);
70 SAVE(PSDR);
71
72 SAVE(Ser1SDCR0);
73
74 /* Clear previous reset status */
75 RCSR = RCSR_HWR | RCSR_SWR | RCSR_WDR | RCSR_SMR;
76
77 /* set resume return address */
78 PSPR = __pa_symbol(cpu_resume);
79
80 /* go zzz */
81 cpu_suspend(0, sa1100_finish_suspend);
82
83 /*
84 * Ensure not to come back here if it wasn't intended
85 */
86 RCSR = RCSR_SMR;
87 PSPR = 0;
88
89 /*
90 * Ensure interrupt sources are disabled; we will re-init
91 * the interrupt subsystem via the device manager.
92 */
93 ICLR = 0;
94 ICCR = 1;
95 ICMR = 0;
96
97 /* restore registers */
98 RESTORE(GPDR);
99 RESTORE(GAFR);
100
101 RESTORE(PPDR);
102 RESTORE(PPSR);
103 RESTORE(PPAR);
104 RESTORE(PSDR);
105
106 RESTORE(Ser1SDCR0);
107
108 GPSR = gpio;
109 GPCR = ~gpio;
110
111 /*
112 * Clear the peripheral sleep-hold bit.
113 */
114 PSSR = PSSR_PH;
115
116 return 0;
117}
118
119static const struct platform_suspend_ops sa11x0_pm_ops = {
120 .enter = sa11x0_pm_enter,
121 .valid = suspend_valid_only_mem,
122};
123
124int __init sa11x0_pm_init(void)
125{
126 suspend_set_ops(ops: &sa11x0_pm_ops);
127 return 0;
128}
129

source code of linux/arch/arm/mach-sa1100/pm.c