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13#include <linux/io.h>
14#include <linux/init.h>
15#include <linux/of.h>
16#include <linux/of_address.h>
17#include <linux/of_platform.h>
18#include <linux/platform_device.h>
19#include <linux/slab.h>
20
21#include "exynos-srom.h"
22
23static const unsigned long exynos_srom_offsets[] = {
24
25 EXYNOS_SROM_BW,
26 EXYNOS_SROM_BC0,
27 EXYNOS_SROM_BC1,
28 EXYNOS_SROM_BC2,
29 EXYNOS_SROM_BC3,
30};
31
32
33
34
35
36
37struct exynos_srom_reg_dump {
38 u32 offset;
39 u32 value;
40};
41
42
43
44
45
46
47
48struct exynos_srom {
49 struct device *dev;
50 void __iomem *reg_base;
51 struct exynos_srom_reg_dump *reg_offset;
52};
53
54static struct exynos_srom_reg_dump *exynos_srom_alloc_reg_dump(
55 const unsigned long *rdump,
56 unsigned long nr_rdump)
57{
58 struct exynos_srom_reg_dump *rd;
59 unsigned int i;
60
61 rd = kcalloc(nr_rdump, sizeof(*rd), GFP_KERNEL);
62 if (!rd)
63 return NULL;
64
65 for (i = 0; i < nr_rdump; ++i)
66 rd[i].offset = rdump[i];
67
68 return rd;
69}
70
71static int exynos_srom_configure_bank(struct exynos_srom *srom,
72 struct device_node *np)
73{
74 u32 bank, width, pmc = 0;
75 u32 timing[6];
76 u32 cs, bw;
77
78 if (of_property_read_u32(np, "reg", &bank))
79 return -EINVAL;
80 if (of_property_read_u32(np, "reg-io-width", &width))
81 width = 1;
82 if (of_property_read_bool(np, "samsung,srom-page-mode"))
83 pmc = 1 << EXYNOS_SROM_BCX__PMC__SHIFT;
84 if (of_property_read_u32_array(np, "samsung,srom-timing", timing,
85 ARRAY_SIZE(timing)))
86 return -EINVAL;
87
88 bank *= 4;
89
90 cs = 1 << EXYNOS_SROM_BW__BYTEENABLE__SHIFT;
91 if (width == 2)
92 cs |= 1 << EXYNOS_SROM_BW__DATAWIDTH__SHIFT;
93
94 bw = readl_relaxed(srom->reg_base + EXYNOS_SROM_BW);
95 bw = (bw & ~(EXYNOS_SROM_BW__CS_MASK << bank)) | (cs << bank);
96 writel_relaxed(bw, srom->reg_base + EXYNOS_SROM_BW);
97
98 writel_relaxed(pmc | (timing[0] << EXYNOS_SROM_BCX__TACP__SHIFT) |
99 (timing[1] << EXYNOS_SROM_BCX__TCAH__SHIFT) |
100 (timing[2] << EXYNOS_SROM_BCX__TCOH__SHIFT) |
101 (timing[3] << EXYNOS_SROM_BCX__TACC__SHIFT) |
102 (timing[4] << EXYNOS_SROM_BCX__TCOS__SHIFT) |
103 (timing[5] << EXYNOS_SROM_BCX__TACS__SHIFT),
104 srom->reg_base + EXYNOS_SROM_BC0 + bank);
105
106 return 0;
107}
108
109static int exynos_srom_probe(struct platform_device *pdev)
110{
111 struct device_node *np, *child;
112 struct exynos_srom *srom;
113 struct device *dev = &pdev->dev;
114 bool bad_bank_config = false;
115
116 np = dev->of_node;
117 if (!np) {
118 dev_err(&pdev->dev, "could not find device info\n");
119 return -EINVAL;
120 }
121
122 srom = devm_kzalloc(&pdev->dev,
123 sizeof(struct exynos_srom), GFP_KERNEL);
124 if (!srom)
125 return -ENOMEM;
126
127 srom->dev = dev;
128 srom->reg_base = of_iomap(np, 0);
129 if (!srom->reg_base) {
130 dev_err(&pdev->dev, "iomap of exynos srom controller failed\n");
131 return -ENOMEM;
132 }
133
134 platform_set_drvdata(pdev, srom);
135
136 srom->reg_offset = exynos_srom_alloc_reg_dump(exynos_srom_offsets,
137 ARRAY_SIZE(exynos_srom_offsets));
138 if (!srom->reg_offset) {
139 iounmap(srom->reg_base);
140 return -ENOMEM;
141 }
142
143 for_each_child_of_node(np, child) {
144 if (exynos_srom_configure_bank(srom, child)) {
145 dev_err(dev,
146 "Could not decode bank configuration for %s\n",
147 child->name);
148 bad_bank_config = true;
149 }
150 }
151
152
153
154
155
156 if (bad_bank_config)
157 return 0;
158
159 return of_platform_populate(np, NULL, NULL, dev);
160}
161
162#ifdef CONFIG_PM_SLEEP
163static void exynos_srom_save(void __iomem *base,
164 struct exynos_srom_reg_dump *rd,
165 unsigned int num_regs)
166{
167 for (; num_regs > 0; --num_regs, ++rd)
168 rd->value = readl(base + rd->offset);
169}
170
171static void exynos_srom_restore(void __iomem *base,
172 const struct exynos_srom_reg_dump *rd,
173 unsigned int num_regs)
174{
175 for (; num_regs > 0; --num_regs, ++rd)
176 writel(rd->value, base + rd->offset);
177}
178
179static int exynos_srom_suspend(struct device *dev)
180{
181 struct exynos_srom *srom = dev_get_drvdata(dev);
182
183 exynos_srom_save(srom->reg_base, srom->reg_offset,
184 ARRAY_SIZE(exynos_srom_offsets));
185 return 0;
186}
187
188static int exynos_srom_resume(struct device *dev)
189{
190 struct exynos_srom *srom = dev_get_drvdata(dev);
191
192 exynos_srom_restore(srom->reg_base, srom->reg_offset,
193 ARRAY_SIZE(exynos_srom_offsets));
194 return 0;
195}
196#endif
197
198static const struct of_device_id of_exynos_srom_ids[] = {
199 {
200 .compatible = "samsung,exynos4210-srom",
201 },
202 {},
203};
204
205static SIMPLE_DEV_PM_OPS(exynos_srom_pm_ops, exynos_srom_suspend, exynos_srom_resume);
206
207static struct platform_driver exynos_srom_driver = {
208 .probe = exynos_srom_probe,
209 .driver = {
210 .name = "exynos-srom",
211 .of_match_table = of_exynos_srom_ids,
212 .pm = &exynos_srom_pm_ops,
213 .suppress_bind_attrs = true,
214 },
215};
216builtin_platform_driver(exynos_srom_driver);
217
