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