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6
7#include <common.h>
8#include <bootcount.h>
9#include <dm.h>
10#include <spi_flash.h>
11
12static const u8 bootcount_magic = 0xbc;
13
14struct bootcount_spi_flash_priv {
15 struct udevice *spi_flash;
16 u32 offset;
17};
18
19static int bootcount_spi_flash_update(struct udevice *dev, u32 offset, u32 len, const void *buf)
20{
21 struct spi_flash *flash = dev_get_uclass_priv(dev);
22 u32 sector_size = flash->sector_size;
23 u32 sector_offset = offset % sector_size;
24 u32 sector = offset - sector_offset;
25 int err = 0;
26
27
28 if (sector_offset + len > sector_size)
29 return -ENOSYS;
30
31 u8 *buffer = malloc(sector_size);
32 if (!buffer)
33 return -ENOMEM;
34
35 err = spi_flash_read_dm(dev, sector, sector_size, buffer);
36 if (err < 0)
37 goto out;
38
39 memcpy(buffer + sector_offset, buf, len);
40
41 err = spi_flash_erase_dm(dev, sector, sector_size);
42 if (err < 0)
43 goto out;
44
45 err = spi_flash_write_dm(dev, sector, sector_size, buffer);
46 if (err < 0)
47 goto out;
48
49out:
50 free(buffer);
51 return err;
52}
53
54static int bootcount_spi_flash_set(struct udevice *dev, const u32 a)
55{
56 struct bootcount_spi_flash_priv *priv = dev_get_priv(dev);
57 const u16 val = bootcount_magic << 8 | (a & 0xff);
58
59 if (bootcount_spi_flash_update(priv->spi_flash, priv->offset, 2, &val) < 0) {
60 debug("%s: write failed\n", __func__);
61 return -EIO;
62 }
63
64 return 0;
65}
66
67static int bootcount_spi_flash_get(struct udevice *dev, u32 *a)
68{
69 struct bootcount_spi_flash_priv *priv = dev_get_priv(dev);
70 u16 val;
71
72 if (spi_flash_read_dm(priv->spi_flash, priv->offset, 2, &val) < 0) {
73 debug("%s: read failed\n", __func__);
74 return -EIO;
75 }
76
77 if (val >> 8 == bootcount_magic) {
78 *a = val & 0xff;
79 return 0;
80 }
81
82 debug("%s: bootcount magic does not match on %04x\n", __func__, val);
83 return -EIO;
84}
85
86static int bootcount_spi_flash_probe(struct udevice *dev)
87{
88 struct ofnode_phandle_args phandle_args;
89 struct bootcount_spi_flash_priv *priv = dev_get_priv(dev);
90 struct udevice *spi_flash;
91
92 if (dev_read_phandle_with_args(dev, "spi-flash", NULL, 0, 0, &phandle_args)) {
93 debug("%s: spi-flash backing device not specified\n", dev->name);
94 return -ENOENT;
95 }
96
97 if (uclass_get_device_by_ofnode(UCLASS_SPI_FLASH, phandle_args.node, &spi_flash)) {
98 debug("%s: could not get backing device\n", dev->name);
99 return -ENODEV;
100 }
101
102 priv->spi_flash = spi_flash;
103 priv->offset = dev_read_u32_default(dev, "offset", 0);
104
105 return 0;
106}
107
108static const struct bootcount_ops bootcount_spi_flash_ops = {
109 .get = bootcount_spi_flash_get,
110 .set = bootcount_spi_flash_set,
111};
112
113static const struct udevice_id bootcount_spi_flash_ids[] = {
114 { .compatible = "u-boot,bootcount-spi-flash" },
115 { }
116};
117
118U_BOOT_DRIVER(bootcount_spi_flash) = {
119 .name = "bootcount-spi-flash",
120 .id = UCLASS_BOOTCOUNT,
121 .priv_auto = sizeof(struct bootcount_spi_flash_priv),
122 .probe = bootcount_spi_flash_probe,
123 .of_match = bootcount_spi_flash_ids,
124 .ops = &bootcount_spi_flash_ops,
125};
126
