1// SPDX-License-Identifier: GPL-2.0
2/*
3 * arch/sh/kernel/cpu/shmobile/pm.c
4 *
5 * Power management support code for SuperH Mobile
6 *
7 * Copyright (C) 2009 Magnus Damm
8 */
9#include <linux/init.h>
10#include <linux/kernel.h>
11#include <linux/io.h>
12#include <linux/suspend.h>
13#include <asm/suspend.h>
14#include <linux/uaccess.h>
15#include <asm/cacheflush.h>
16#include <asm/bl_bit.h>
17
18/*
19 * Notifier lists for pre/post sleep notification
20 */
21ATOMIC_NOTIFIER_HEAD(sh_mobile_pre_sleep_notifier_list);
22ATOMIC_NOTIFIER_HEAD(sh_mobile_post_sleep_notifier_list);
23
24/*
25 * Sleep modes available on SuperH Mobile:
26 *
27 * Sleep mode is just plain "sleep" instruction
28 * Sleep Self-Refresh mode is above plus RAM put in Self-Refresh
29 * Standby Self-Refresh mode is above plus stopped clocks
30 */
31#define SUSP_MODE_SLEEP (SUSP_SH_SLEEP)
32#define SUSP_MODE_SLEEP_SF (SUSP_SH_SLEEP | SUSP_SH_SF)
33#define SUSP_MODE_STANDBY_SF (SUSP_SH_STANDBY | SUSP_SH_SF)
34#define SUSP_MODE_RSTANDBY_SF \
35 (SUSP_SH_RSTANDBY | SUSP_SH_MMU | SUSP_SH_REGS | SUSP_SH_SF)
36 /*
37 * U-standby mode is unsupported since it needs bootloader hacks
38 */
39
40#ifdef CONFIG_CPU_SUBTYPE_SH7724
41#define RAM_BASE 0xfd800000 /* RSMEM */
42#else
43#define RAM_BASE 0xe5200000 /* ILRAM */
44#endif
45
46void sh_mobile_call_standby(unsigned long mode)
47{
48 void *onchip_mem = (void *)RAM_BASE;
49 struct sh_sleep_data *sdp = onchip_mem;
50 void (*standby_onchip_mem)(unsigned long, unsigned long);
51
52 /* code located directly after data structure */
53 standby_onchip_mem = (void *)(sdp + 1);
54
55 atomic_notifier_call_chain(nh: &sh_mobile_pre_sleep_notifier_list,
56 val: mode, NULL);
57
58 /* flush the caches if MMU flag is set */
59 if (mode & SUSP_SH_MMU)
60 flush_cache_all();
61
62 /* Let assembly snippet in on-chip memory handle the rest */
63 standby_onchip_mem(mode, RAM_BASE);
64
65 atomic_notifier_call_chain(nh: &sh_mobile_post_sleep_notifier_list,
66 val: mode, NULL);
67}
68
69extern char sh_mobile_sleep_enter_start;
70extern char sh_mobile_sleep_enter_end;
71
72extern char sh_mobile_sleep_resume_start;
73extern char sh_mobile_sleep_resume_end;
74
75unsigned long sh_mobile_sleep_supported = SUSP_SH_SLEEP;
76
77void sh_mobile_register_self_refresh(unsigned long flags,
78 void *pre_start, void *pre_end,
79 void *post_start, void *post_end)
80{
81 void *onchip_mem = (void *)RAM_BASE;
82 void *vp;
83 struct sh_sleep_data *sdp;
84 int n;
85
86 /* part 0: data area */
87 sdp = onchip_mem;
88 sdp->addr.stbcr = 0xa4150020; /* STBCR */
89 sdp->addr.bar = 0xa4150040; /* BAR */
90 sdp->addr.pteh = 0xff000000; /* PTEH */
91 sdp->addr.ptel = 0xff000004; /* PTEL */
92 sdp->addr.ttb = 0xff000008; /* TTB */
93 sdp->addr.tea = 0xff00000c; /* TEA */
94 sdp->addr.mmucr = 0xff000010; /* MMUCR */
95 sdp->addr.ptea = 0xff000034; /* PTEA */
96 sdp->addr.pascr = 0xff000070; /* PASCR */
97 sdp->addr.irmcr = 0xff000078; /* IRMCR */
98 sdp->addr.ccr = 0xff00001c; /* CCR */
99 sdp->addr.ramcr = 0xff000074; /* RAMCR */
100 vp = sdp + 1;
101
102 /* part 1: common code to enter sleep mode */
103 n = &sh_mobile_sleep_enter_end - &sh_mobile_sleep_enter_start;
104 memcpy(vp, &sh_mobile_sleep_enter_start, n);
105 vp += roundup(n, 4);
106
107 /* part 2: board specific code to enter self-refresh mode */
108 n = pre_end - pre_start;
109 memcpy(vp, pre_start, n);
110 sdp->sf_pre = (unsigned long)vp;
111 vp += roundup(n, 4);
112
113 /* part 3: board specific code to resume from self-refresh mode */
114 n = post_end - post_start;
115 memcpy(vp, post_start, n);
116 sdp->sf_post = (unsigned long)vp;
117 vp += roundup(n, 4);
118
119 /* part 4: common code to resume from sleep mode */
120 WARN_ON(vp > (onchip_mem + 0x600));
121 vp = onchip_mem + 0x600; /* located at interrupt vector */
122 n = &sh_mobile_sleep_resume_end - &sh_mobile_sleep_resume_start;
123 memcpy(vp, &sh_mobile_sleep_resume_start, n);
124 sdp->resume = (unsigned long)vp;
125
126 sh_mobile_sleep_supported |= flags;
127}
128
129static int sh_pm_enter(suspend_state_t state)
130{
131 if (!(sh_mobile_sleep_supported & SUSP_MODE_STANDBY_SF))
132 return -ENXIO;
133
134 local_irq_disable();
135 set_bl_bit();
136 sh_mobile_call_standby(SUSP_MODE_STANDBY_SF);
137 local_irq_disable();
138 clear_bl_bit();
139 return 0;
140}
141
142static const struct platform_suspend_ops sh_pm_ops = {
143 .enter = sh_pm_enter,
144 .valid = suspend_valid_only_mem,
145};
146
147static int __init sh_pm_init(void)
148{
149 suspend_set_ops(ops: &sh_pm_ops);
150 return sh_mobile_setup_cpuidle();
151}
152
153late_initcall(sh_pm_init);
154

source code of linux/arch/sh/kernel/cpu/shmobile/pm.c