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gerrit-public.fairphone.software / kernel / msm-4.9 / f1e9637f4b49690a6c5793f1745f743506b1bfd1 / . / arch / arm / mach-shmobile / pm-rcar.c
blob: 1f465a12d1b1932422935e35a1c8f3f7bb2a4b1b [file] [log] [blame]
Magnus Damma6557eb2014-01-15 16:43:08 +0900[diff] [blame]1/*
2 * R-Car SYSC Power management support
3 *
4 * Copyright (C) 2014 Magnus Damm
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License. See the file "COPYING" in the main directory of this archive
8 * for more details.
9 */
10
11#include <linux/delay.h>
12#include <linux/err.h>
13#include <linux/mm.h>
14#include <linux/spinlock.h>
15#include <asm/io.h>
16#include <mach/pm-rcar.h>
17
Magnus Damma6557eb2014-01-15 16:43:08 +0900[diff] [blame]18/* SYSC */
19#define SYSCSR 0x00
20#define SYSCISR 0x04
21#define SYSCISCR 0x08
22
23#define PWRSR_OFFS 0x00
24#define PWROFFCR_OFFS 0x04
25#define PWRONCR_OFFS 0x0c
26#define PWRER_OFFS 0x14
27
28#define SYSCSR_RETRIES 100
29#define SYSCSR_DELAY_US 1
30
31#define SYSCISR_RETRIES 1000
32#define SYSCISR_DELAY_US 1
33
34#if defined(CONFIG_PM) || defined(CONFIG_SMP)
35
Magnus Dammc4ca5d82014-02-24 14:52:12 +0900[diff] [blame]36static void __iomem *rcar_sysc_base;
Magnus Damma6557eb2014-01-15 16:43:08 +0900[diff] [blame]37static DEFINE_SPINLOCK(rcar_sysc_lock); /* SMP CPUs + I/O devices */
38
39static int rcar_sysc_pwr_on_off(struct rcar_sysc_ch *sysc_ch,
40 int sr_bit, int reg_offs)
41{
42 int k;
43
44 for (k = 0; k < SYSCSR_RETRIES; k++) {
45 if (ioread32(rcar_sysc_base + SYSCSR) & (1 << sr_bit))
46 break;
47 udelay(SYSCSR_DELAY_US);
48 }
49
50 if (k == SYSCSR_RETRIES)
51 return -EAGAIN;
52
53 iowrite32(1 << sysc_ch->chan_bit,
54 rcar_sysc_base + sysc_ch->chan_offs + reg_offs);
55
56 return 0;
57}
58
59static int rcar_sysc_pwr_off(struct rcar_sysc_ch *sysc_ch)
60{
61 return rcar_sysc_pwr_on_off(sysc_ch, 0, PWROFFCR_OFFS);
62}
63
64static int rcar_sysc_pwr_on(struct rcar_sysc_ch *sysc_ch)
65{
66 return rcar_sysc_pwr_on_off(sysc_ch, 1, PWRONCR_OFFS);
67}
68
69static int rcar_sysc_update(struct rcar_sysc_ch *sysc_ch,
70 int (*on_off_fn)(struct rcar_sysc_ch *))
71{
72 unsigned int isr_mask = 1 << sysc_ch->isr_bit;
73 unsigned int chan_mask = 1 << sysc_ch->chan_bit;
74 unsigned int status;
75 unsigned long flags;
76 int ret = 0;
77 int k;
78
79 spin_lock_irqsave(&rcar_sysc_lock, flags);
80
81 iowrite32(isr_mask, rcar_sysc_base + SYSCISCR);
82
83 do {
84 ret = on_off_fn(sysc_ch);
85 if (ret)
86 goto out;
87
88 status = ioread32(rcar_sysc_base +
89 sysc_ch->chan_offs + PWRER_OFFS);
90 } while (status & chan_mask);
91
92 for (k = 0; k < SYSCISR_RETRIES; k++) {
93 if (ioread32(rcar_sysc_base + SYSCISR) & isr_mask)
94 break;
95 udelay(SYSCISR_DELAY_US);
96 }
97
98 if (k == SYSCISR_RETRIES)
99 ret = -EIO;
100
101 iowrite32(isr_mask, rcar_sysc_base + SYSCISCR);
102
103 out:
104 spin_unlock_irqrestore(&rcar_sysc_lock, flags);
105
106 pr_debug("sysc power domain %d: %08x -> %d\n",
107 sysc_ch->isr_bit, ioread32(rcar_sysc_base + SYSCISR), ret);
108 return ret;
109}
110
111int rcar_sysc_power_down(struct rcar_sysc_ch *sysc_ch)
112{
113 return rcar_sysc_update(sysc_ch, rcar_sysc_pwr_off);
114}
115
116int rcar_sysc_power_up(struct rcar_sysc_ch *sysc_ch)
117{
118 return rcar_sysc_update(sysc_ch, rcar_sysc_pwr_on);
119}
120
121bool rcar_sysc_power_is_off(struct rcar_sysc_ch *sysc_ch)
122{
123 unsigned int st;
124
125 st = ioread32(rcar_sysc_base + sysc_ch->chan_offs + PWRSR_OFFS);
126 if (st & (1 << sysc_ch->chan_bit))
127 return true;
128
129 return false;
130}
131
132void __iomem *rcar_sysc_init(phys_addr_t base)
133{
134 rcar_sysc_base = ioremap_nocache(base, PAGE_SIZE);
135 if (!rcar_sysc_base)
136 panic("unable to ioremap R-Car SYSC hardware block\n");
137
138 return rcar_sysc_base;
139}
140
141#endif /* CONFIG_PM || CONFIG_SMP */