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 #include <asm/bl_bit.h>
20 
21 /*
22  * Notifier lists for pre/post sleep notification
23  */
24 ATOMIC_NOTIFIER_HEAD(sh_mobile_pre_sleep_notifier_list);
25 ATOMIC_NOTIFIER_HEAD(sh_mobile_post_sleep_notifier_list);
26 
27 /*
28  * Sleep modes available on SuperH Mobile:
29  *
30  * Sleep mode is just plain "sleep" instruction
31  * Sleep Self-Refresh mode is above plus RAM put in Self-Refresh
32  * Standby Self-Refresh mode is above plus stopped clocks
33  */
34 #define SUSP_MODE_SLEEP		(SUSP_SH_SLEEP)
35 #define SUSP_MODE_SLEEP_SF	(SUSP_SH_SLEEP | SUSP_SH_SF)
36 #define SUSP_MODE_STANDBY_SF	(SUSP_SH_STANDBY | SUSP_SH_SF)
37 #define SUSP_MODE_RSTANDBY_SF \
38 	(SUSP_SH_RSTANDBY | SUSP_SH_MMU | SUSP_SH_REGS | SUSP_SH_SF)
39  /*
40   * U-standby mode is unsupported since it needs bootloader hacks
41   */
42 
43 #ifdef CONFIG_CPU_SUBTYPE_SH7724
44 #define RAM_BASE 0xfd800000 /* RSMEM */
45 #else
46 #define RAM_BASE 0xe5200000 /* ILRAM */
47 #endif
48 
sh_mobile_call_standby(unsigned long mode)49 void sh_mobile_call_standby(unsigned long mode)
50 {
51 	void *onchip_mem = (void *)RAM_BASE;
52 	struct sh_sleep_data *sdp = onchip_mem;
53 	void (*standby_onchip_mem)(unsigned long, unsigned long);
54 
55 	/* code located directly after data structure */
56 	standby_onchip_mem = (void *)(sdp + 1);
57 
58 	atomic_notifier_call_chain(&sh_mobile_pre_sleep_notifier_list,
59 				   mode, NULL);
60 
61 	/* flush the caches if MMU flag is set */
62 	if (mode & SUSP_SH_MMU)
63 		flush_cache_all();
64 
65 	/* Let assembly snippet in on-chip memory handle the rest */
66 	standby_onchip_mem(mode, RAM_BASE);
67 
68 	atomic_notifier_call_chain(&sh_mobile_post_sleep_notifier_list,
69 				   mode, NULL);
70 }
71 
72 extern char sh_mobile_sleep_enter_start;
73 extern char sh_mobile_sleep_enter_end;
74 
75 extern char sh_mobile_sleep_resume_start;
76 extern char sh_mobile_sleep_resume_end;
77 
78 unsigned long sh_mobile_sleep_supported = SUSP_SH_SLEEP;
79 
sh_mobile_register_self_refresh(unsigned long flags,void * pre_start,void * pre_end,void * post_start,void * post_end)80 void sh_mobile_register_self_refresh(unsigned long flags,
81 				     void *pre_start, void *pre_end,
82 				     void *post_start, void *post_end)
83 {
84 	void *onchip_mem = (void *)RAM_BASE;
85 	void *vp;
86 	struct sh_sleep_data *sdp;
87 	int n;
88 
89 	/* part 0: data area */
90 	sdp = onchip_mem;
91 	sdp->addr.stbcr = 0xa4150020; /* STBCR */
92 	sdp->addr.bar = 0xa4150040; /* BAR */
93 	sdp->addr.pteh = 0xff000000; /* PTEH */
94 	sdp->addr.ptel = 0xff000004; /* PTEL */
95 	sdp->addr.ttb = 0xff000008; /* TTB */
96 	sdp->addr.tea = 0xff00000c; /* TEA */
97 	sdp->addr.mmucr = 0xff000010; /* MMUCR */
98 	sdp->addr.ptea = 0xff000034; /* PTEA */
99 	sdp->addr.pascr = 0xff000070; /* PASCR */
100 	sdp->addr.irmcr = 0xff000078; /* IRMCR */
101 	sdp->addr.ccr = 0xff00001c; /* CCR */
102 	sdp->addr.ramcr = 0xff000074; /* RAMCR */
103 	vp = sdp + 1;
104 
105 	/* part 1: common code to enter sleep mode */
106 	n = &sh_mobile_sleep_enter_end - &sh_mobile_sleep_enter_start;
107 	memcpy(vp, &sh_mobile_sleep_enter_start, n);
108 	vp += roundup(n, 4);
109 
110 	/* part 2: board specific code to enter self-refresh mode */
111 	n = pre_end - pre_start;
112 	memcpy(vp, pre_start, n);
113 	sdp->sf_pre = (unsigned long)vp;
114 	vp += roundup(n, 4);
115 
116 	/* part 3: board specific code to resume from self-refresh mode */
117 	n = post_end - post_start;
118 	memcpy(vp, post_start, n);
119 	sdp->sf_post = (unsigned long)vp;
120 	vp += roundup(n, 4);
121 
122 	/* part 4: common code to resume from sleep mode */
123 	WARN_ON(vp > (onchip_mem + 0x600));
124 	vp = onchip_mem + 0x600; /* located at interrupt vector */
125 	n = &sh_mobile_sleep_resume_end - &sh_mobile_sleep_resume_start;
126 	memcpy(vp, &sh_mobile_sleep_resume_start, n);
127 	sdp->resume = (unsigned long)vp;
128 
129 	sh_mobile_sleep_supported |= flags;
130 }
131 
sh_pm_enter(suspend_state_t state)132 static int sh_pm_enter(suspend_state_t state)
133 {
134 	if (!(sh_mobile_sleep_supported & SUSP_MODE_STANDBY_SF))
135 		return -ENXIO;
136 
137 	local_irq_disable();
138 	set_bl_bit();
139 	sh_mobile_call_standby(SUSP_MODE_STANDBY_SF);
140 	local_irq_disable();
141 	clear_bl_bit();
142 	return 0;
143 }
144 
145 static const struct platform_suspend_ops sh_pm_ops = {
146 	.enter          = sh_pm_enter,
147 	.valid          = suspend_valid_only_mem,
148 };
149 
sh_pm_init(void)150 static int __init sh_pm_init(void)
151 {
152 	suspend_set_ops(&sh_pm_ops);
153 	sh_mobile_setup_cpuidle();
154 	return 0;
155 }
156 
157 late_initcall(sh_pm_init);
158