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8#include <common.h>
9#include <clk.h>
10#include <dm.h>
11#include <rng.h>
12#include <asm/io.h>
13
14struct meson_rng_plat {
15 fdt_addr_t base;
16 struct clk clk;
17};
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27static int meson_rng_read(struct udevice *dev, void *data, size_t len)
28{
29 struct meson_rng_plat *pdata = dev_get_plat(dev);
30 char *buffer = (char *)data;
31
32 while (len) {
33 u32 rand = readl(pdata->base);
34 size_t step;
35
36 if (len >= 4)
37 step = 4;
38 else
39 step = len;
40 memcpy(buffer, &rand, step);
41 buffer += step;
42 len -= step;
43 }
44 return 0;
45}
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52
53static int meson_rng_probe(struct udevice *dev)
54{
55 struct meson_rng_plat *pdata = dev_get_plat(dev);
56 int err;
57
58 err = clk_enable(&pdata->clk);
59 if (err)
60 return err;
61
62 return 0;
63}
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70
71static int meson_rng_remove(struct udevice *dev)
72{
73 struct meson_rng_plat *pdata = dev_get_plat(dev);
74
75 return clk_disable(&pdata->clk);
76}
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83
84static int meson_rng_of_to_plat(struct udevice *dev)
85{
86 struct meson_rng_plat *pdata = dev_get_plat(dev);
87 int err;
88
89 pdata->base = dev_read_addr(dev);
90 if (!pdata->base)
91 return -ENODEV;
92
93
94 err = clk_get_by_name(dev, "core", &pdata->clk);
95 if (err && err != -ENODATA)
96 return err;
97
98 return 0;
99}
100
101static const struct dm_rng_ops meson_rng_ops = {
102 .read = meson_rng_read,
103};
104
105static const struct udevice_id meson_rng_match[] = {
106 {
107 .compatible = "amlogic,meson-rng",
108 },
109 {},
110};
111
112U_BOOT_DRIVER(meson_rng) = {
113 .name = "meson-rng",
114 .id = UCLASS_RNG,
115 .of_match = meson_rng_match,
116 .ops = &meson_rng_ops,
117 .probe = meson_rng_probe,
118 .remove = meson_rng_remove,
119 .plat_auto = sizeof(struct meson_rng_plat),
120 .of_to_plat = meson_rng_of_to_plat,
121};
122