xref: /openbmc/linux/arch/sh/kernel/cpu/shmobile/pm.c (revision b6dcefde)
1 /*
2  * arch/sh/kernel/cpu/shmobile/pm.c
3  *
4  * Power management support code for SuperH Mobile
5  *
6  *  Copyright (C) 2009 Magnus Damm
7  *
8  * This file is subject to the terms and conditions of the GNU General Public
9  * License.  See the file "COPYING" in the main directory of this archive
10  * for more details.
11  */
12 #include <linux/init.h>
13 #include <linux/kernel.h>
14 #include <linux/io.h>
15 #include <linux/suspend.h>
16 #include <asm/suspend.h>
17 #include <asm/uaccess.h>
18 #include <asm/cacheflush.h>
19 
20 /*
21  * Notifier lists for pre/post sleep notification
22  */
23 ATOMIC_NOTIFIER_HEAD(sh_mobile_pre_sleep_notifier_list);
24 ATOMIC_NOTIFIER_HEAD(sh_mobile_post_sleep_notifier_list);
25 
26 /*
27  * Sleep modes available on SuperH Mobile:
28  *
29  * Sleep mode is just plain "sleep" instruction
30  * Sleep Self-Refresh mode is above plus RAM put in Self-Refresh
31  * Standby Self-Refresh mode is above plus stopped clocks
32  */
33 #define SUSP_MODE_SLEEP		(SUSP_SH_SLEEP)
34 #define SUSP_MODE_SLEEP_SF	(SUSP_SH_SLEEP | SUSP_SH_SF)
35 #define SUSP_MODE_STANDBY_SF	(SUSP_SH_STANDBY | SUSP_SH_SF)
36 #define SUSP_MODE_RSTANDBY	(SUSP_SH_RSTANDBY | SUSP_SH_MMU | SUSP_SH_SF)
37  /*
38   * U-standby mode is unsupported since it needs bootloader hacks
39   */
40 
41 #ifdef CONFIG_CPU_SUBTYPE_SH7724
42 #define RAM_BASE 0xfd800000 /* RSMEM */
43 #else
44 #define RAM_BASE 0xe5200000 /* ILRAM */
45 #endif
46 
47 void sh_mobile_call_standby(unsigned long mode)
48 {
49 	void *onchip_mem = (void *)RAM_BASE;
50 	struct sh_sleep_data *sdp = onchip_mem;
51 	void (*standby_onchip_mem)(unsigned long, unsigned long);
52 
53 	/* code located directly after data structure */
54 	standby_onchip_mem = (void *)(sdp + 1);
55 
56 	atomic_notifier_call_chain(&sh_mobile_pre_sleep_notifier_list,
57 				   mode, NULL);
58 
59 	/* flush the caches if MMU flag is set */
60 	if (mode & SUSP_SH_MMU)
61 		flush_cache_all();
62 
63 	/* Let assembly snippet in on-chip memory handle the rest */
64 	standby_onchip_mem(mode, RAM_BASE);
65 
66 	atomic_notifier_call_chain(&sh_mobile_post_sleep_notifier_list,
67 				   mode, NULL);
68 }
69 
70 extern char sh_mobile_sleep_enter_start;
71 extern char sh_mobile_sleep_enter_end;
72 
73 extern char sh_mobile_sleep_resume_start;
74 extern char sh_mobile_sleep_resume_end;
75 
76 unsigned long sh_mobile_sleep_supported = SUSP_SH_SLEEP;
77 
78 void sh_mobile_register_self_refresh(unsigned long flags,
79 				     void *pre_start, void *pre_end,
80 				     void *post_start, void *post_end)
81 {
82 	void *onchip_mem = (void *)RAM_BASE;
83 	void *vp;
84 	struct sh_sleep_data *sdp;
85 	int n;
86 
87 	/* part 0: data area */
88 	sdp = onchip_mem;
89 	sdp->addr.stbcr = 0xa4150020; /* STBCR */
90 	sdp->addr.bar = 0xa4150040; /* BAR */
91 	sdp->addr.pteh = 0xff000000; /* PTEH */
92 	sdp->addr.ptel = 0xff000004; /* PTEL */
93 	sdp->addr.ttb = 0xff000008; /* TTB */
94 	sdp->addr.tea = 0xff00000c; /* TEA */
95 	sdp->addr.mmucr = 0xff000010; /* MMUCR */
96 	sdp->addr.ptea = 0xff000034; /* PTEA */
97 	sdp->addr.pascr = 0xff000070; /* PASCR */
98 	sdp->addr.irmcr = 0xff000078; /* IRMCR */
99 	sdp->addr.ccr = 0xff00001c; /* CCR */
100 	sdp->addr.ramcr = 0xff000074; /* RAMCR */
101 	vp = sdp + 1;
102 
103 	/* part 1: common code to enter sleep mode */
104 	n = &sh_mobile_sleep_enter_end - &sh_mobile_sleep_enter_start;
105 	memcpy(vp, &sh_mobile_sleep_enter_start, n);
106 	vp += roundup(n, 4);
107 
108 	/* part 2: board specific code to enter self-refresh mode */
109 	n = pre_end - pre_start;
110 	memcpy(vp, pre_start, n);
111 	sdp->sf_pre = (unsigned long)vp;
112 	vp += roundup(n, 4);
113 
114 	/* part 3: board specific code to resume from self-refresh mode */
115 	n = post_end - post_start;
116 	memcpy(vp, post_start, n);
117 	sdp->sf_post = (unsigned long)vp;
118 	vp += roundup(n, 4);
119 
120 	/* part 4: common code to resume from sleep mode */
121 	WARN_ON(vp > (onchip_mem + 0x600));
122 	vp = onchip_mem + 0x600; /* located at interrupt vector */
123 	n = &sh_mobile_sleep_resume_end - &sh_mobile_sleep_resume_start;
124 	memcpy(vp, &sh_mobile_sleep_resume_start, n);
125 	sdp->resume = (unsigned long)vp;
126 
127 	sh_mobile_sleep_supported |= flags;
128 }
129 
130 static int sh_pm_enter(suspend_state_t state)
131 {
132 	if (!(sh_mobile_sleep_supported & SUSP_MODE_STANDBY_SF))
133 		return -ENXIO;
134 
135 	local_irq_disable();
136 	set_bl_bit();
137 	sh_mobile_call_standby(SUSP_MODE_STANDBY_SF);
138 	local_irq_disable();
139 	clear_bl_bit();
140 	return 0;
141 }
142 
143 static struct platform_suspend_ops sh_pm_ops = {
144 	.enter          = sh_pm_enter,
145 	.valid          = suspend_valid_only_mem,
146 };
147 
148 static int __init sh_pm_init(void)
149 {
150 	suspend_set_ops(&sh_pm_ops);
151 	sh_mobile_setup_cpuidle();
152 	return 0;
153 }
154 
155 late_initcall(sh_pm_init);
156