1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
|
/*
* Copyright (c) 2015 Samsung Electronics Co., Ltd.
* http://www.samsung.com/
*
* EXYNOS - SROM Controller support
* Author: Pankaj Dubey <pankaj.dubey@samsung.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/io.h>
#include <linux/init.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include "exynos-srom.h"
static const unsigned long exynos_srom_offsets[] = {
/* SROM side */
EXYNOS_SROM_BW,
EXYNOS_SROM_BC0,
EXYNOS_SROM_BC1,
EXYNOS_SROM_BC2,
EXYNOS_SROM_BC3,
};
/**
* struct exynos_srom_reg_dump: register dump of SROM Controller registers.
* @offset: srom register offset from the controller base address.
* @value: the value of register under the offset.
*/
struct exynos_srom_reg_dump {
u32 offset;
u32 value;
};
/**
* struct exynos_srom: platform data for exynos srom controller driver.
* @dev: platform device pointer
* @reg_base: srom base address
* @reg_offset: exynos_srom_reg_dump pointer to hold offset and its value.
*/
struct exynos_srom {
struct device *dev;
void __iomem *reg_base;
struct exynos_srom_reg_dump *reg_offset;
};
static struct exynos_srom_reg_dump *exynos_srom_alloc_reg_dump(
const unsigned long *rdump,
unsigned long nr_rdump)
{
struct exynos_srom_reg_dump *rd;
unsigned int i;
rd = kcalloc(nr_rdump, sizeof(*rd), GFP_KERNEL);
if (!rd)
return NULL;
for (i = 0; i < nr_rdump; ++i)
rd[i].offset = rdump[i];
return rd;
}
static int exynos_srom_configure_bank(struct exynos_srom *srom,
struct device_node *np)
{
u32 bank, width, pmc = 0;
u32 timing[6];
u32 cs, bw;
if (of_property_read_u32(np, "reg", &bank))
return -EINVAL;
if (of_property_read_u32(np, "reg-io-width", &width))
width = 1;
if (of_property_read_bool(np, "samsung,srom-page-mode"))
pmc = 1 << EXYNOS_SROM_BCX__PMC__SHIFT;
if (of_property_read_u32_array(np, "samsung,srom-timing", timing,
ARRAY_SIZE(timing)))
return -EINVAL;
bank *= 4; /* Convert bank into shift/offset */
cs = 1 << EXYNOS_SROM_BW__BYTEENABLE__SHIFT;
if (width == 2)
cs |= 1 << EXYNOS_SROM_BW__DATAWIDTH__SHIFT;
bw = readl_relaxed(srom->reg_base + EXYNOS_SROM_BW);
bw = (bw & ~(EXYNOS_SROM_BW__CS_MASK << bank)) | (cs << bank);
writel_relaxed(bw, srom->reg_base + EXYNOS_SROM_BW);
writel_relaxed(pmc | (timing[0] << EXYNOS_SROM_BCX__TACP__SHIFT) |
(timing[1] << EXYNOS_SROM_BCX__TCAH__SHIFT) |
(timing[2] << EXYNOS_SROM_BCX__TCOH__SHIFT) |
(timing[3] << EXYNOS_SROM_BCX__TACC__SHIFT) |
(timing[4] << EXYNOS_SROM_BCX__TCOS__SHIFT) |
(timing[5] << EXYNOS_SROM_BCX__TACS__SHIFT),
srom->reg_base + EXYNOS_SROM_BC0 + bank);
return 0;
}
static int exynos_srom_probe(struct platform_device *pdev)
{
struct device_node *np, *child;
struct exynos_srom *srom;
struct device *dev = &pdev->dev;
bool bad_bank_config = false;
np = dev->of_node;
if (!np) {
dev_err(&pdev->dev, "could not find device info\n");
return -EINVAL;
}
srom = devm_kzalloc(&pdev->dev,
sizeof(struct exynos_srom), GFP_KERNEL);
if (!srom)
return -ENOMEM;
srom->dev = dev;
srom->reg_base = of_iomap(np, 0);
if (!srom->reg_base) {
dev_err(&pdev->dev, "iomap of exynos srom controller failed\n");
return -ENOMEM;
}
platform_set_drvdata(pdev, srom);
srom->reg_offset = exynos_srom_alloc_reg_dump(exynos_srom_offsets,
ARRAY_SIZE(exynos_srom_offsets));
if (!srom->reg_offset) {
iounmap(srom->reg_base);
return -ENOMEM;
}
for_each_child_of_node(np, child) {
if (exynos_srom_configure_bank(srom, child)) {
dev_err(dev,
"Could not decode bank configuration for %s\n",
child->name);
bad_bank_config = true;
}
}
/*
* If any bank failed to configure, we still provide suspend/resume,
* but do not probe child devices
*/
if (bad_bank_config)
return 0;
return of_platform_populate(np, NULL, NULL, dev);
}
#ifdef CONFIG_PM_SLEEP
static void exynos_srom_save(void __iomem *base,
struct exynos_srom_reg_dump *rd,
unsigned int num_regs)
{
for (; num_regs > 0; --num_regs, ++rd)
rd->value = readl(base + rd->offset);
}
static void exynos_srom_restore(void __iomem *base,
const struct exynos_srom_reg_dump *rd,
unsigned int num_regs)
{
for (; num_regs > 0; --num_regs, ++rd)
writel(rd->value, base + rd->offset);
}
static int exynos_srom_suspend(struct device *dev)
{
struct exynos_srom *srom = dev_get_drvdata(dev);
exynos_srom_save(srom->reg_base, srom->reg_offset,
ARRAY_SIZE(exynos_srom_offsets));
return 0;
}
static int exynos_srom_resume(struct device *dev)
{
struct exynos_srom *srom = dev_get_drvdata(dev);
exynos_srom_restore(srom->reg_base, srom->reg_offset,
ARRAY_SIZE(exynos_srom_offsets));
return 0;
}
#endif
static const struct of_device_id of_exynos_srom_ids[] = {
{
.compatible = "samsung,exynos4210-srom",
},
{},
};
static SIMPLE_DEV_PM_OPS(exynos_srom_pm_ops, exynos_srom_suspend, exynos_srom_resume);
static struct platform_driver exynos_srom_driver = {
.probe = exynos_srom_probe,
.driver = {
.name = "exynos-srom",
.of_match_table = of_exynos_srom_ids,
.pm = &exynos_srom_pm_ops,
.suppress_bind_attrs = true,
},
};
builtin_platform_driver(exynos_srom_driver);
|
