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
217
218
219
220
221
222
|
// SPDX-License-Identifier: GPL-2.0
#include <linux/iopoll.h>
#include <linux/module.h>
#include <linux/nvmem-provider.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#define OTP_OTP_PWR_DN(t) (t + 0x00)
#define OTP_OTP_PWR_DN_OTP_PWRDN_N BIT(0)
#define OTP_OTP_ADDR_HI(t) (t + 0x04)
#define OTP_OTP_ADDR_LO(t) (t + 0x08)
#define OTP_OTP_PRGM_DATA(t) (t + 0x10)
#define OTP_OTP_PRGM_MODE(t) (t + 0x14)
#define OTP_OTP_PRGM_MODE_OTP_PGM_MODE_BYTE BIT(0)
#define OTP_OTP_RD_DATA(t) (t + 0x18)
#define OTP_OTP_FUNC_CMD(t) (t + 0x20)
#define OTP_OTP_FUNC_CMD_OTP_PROGRAM BIT(1)
#define OTP_OTP_FUNC_CMD_OTP_READ BIT(0)
#define OTP_OTP_CMD_GO(t) (t + 0x28)
#define OTP_OTP_CMD_GO_OTP_GO BIT(0)
#define OTP_OTP_PASS_FAIL(t) (t + 0x2c)
#define OTP_OTP_PASS_FAIL_OTP_READ_PROHIBITED BIT(3)
#define OTP_OTP_PASS_FAIL_OTP_WRITE_PROHIBITED BIT(2)
#define OTP_OTP_PASS_FAIL_OTP_FAIL BIT(0)
#define OTP_OTP_STATUS(t) (t + 0x30)
#define OTP_OTP_STATUS_OTP_CPUMPEN BIT(1)
#define OTP_OTP_STATUS_OTP_BUSY BIT(0)
#define OTP_MEM_SIZE 8192
#define OTP_SLEEP_US 10
#define OTP_TIMEOUT_US 500000
struct lan9662_otp {
struct device *dev;
void __iomem *base;
};
static bool lan9662_otp_wait_flag_clear(void __iomem *reg, u32 flag)
{
u32 val;
return readl_poll_timeout(reg, val, !(val & flag),
OTP_SLEEP_US, OTP_TIMEOUT_US);
}
static int lan9662_otp_power(struct lan9662_otp *otp, bool up)
{
void __iomem *pwrdn = OTP_OTP_PWR_DN(otp->base);
if (up) {
writel(readl(pwrdn) & ~OTP_OTP_PWR_DN_OTP_PWRDN_N, pwrdn);
if (lan9662_otp_wait_flag_clear(OTP_OTP_STATUS(otp->base),
OTP_OTP_STATUS_OTP_CPUMPEN))
return -ETIMEDOUT;
} else {
writel(readl(pwrdn) | OTP_OTP_PWR_DN_OTP_PWRDN_N, pwrdn);
}
return 0;
}
static int lan9662_otp_execute(struct lan9662_otp *otp)
{
if (lan9662_otp_wait_flag_clear(OTP_OTP_CMD_GO(otp->base),
OTP_OTP_CMD_GO_OTP_GO))
return -ETIMEDOUT;
if (lan9662_otp_wait_flag_clear(OTP_OTP_STATUS(otp->base),
OTP_OTP_STATUS_OTP_BUSY))
return -ETIMEDOUT;
return 0;
}
static void lan9662_otp_set_address(struct lan9662_otp *otp, u32 offset)
{
writel(0xff & (offset >> 8), OTP_OTP_ADDR_HI(otp->base));
writel(0xff & offset, OTP_OTP_ADDR_LO(otp->base));
}
static int lan9662_otp_read_byte(struct lan9662_otp *otp, u32 offset, u8 *dst)
{
u32 pass;
int rc;
lan9662_otp_set_address(otp, offset);
writel(OTP_OTP_FUNC_CMD_OTP_READ, OTP_OTP_FUNC_CMD(otp->base));
writel(OTP_OTP_CMD_GO_OTP_GO, OTP_OTP_CMD_GO(otp->base));
rc = lan9662_otp_execute(otp);
if (!rc) {
pass = readl(OTP_OTP_PASS_FAIL(otp->base));
if (pass & OTP_OTP_PASS_FAIL_OTP_READ_PROHIBITED)
return -EACCES;
*dst = (u8) readl(OTP_OTP_RD_DATA(otp->base));
}
return rc;
}
static int lan9662_otp_write_byte(struct lan9662_otp *otp, u32 offset, u8 data)
{
u32 pass;
int rc;
lan9662_otp_set_address(otp, offset);
writel(OTP_OTP_PRGM_MODE_OTP_PGM_MODE_BYTE, OTP_OTP_PRGM_MODE(otp->base));
writel(data, OTP_OTP_PRGM_DATA(otp->base));
writel(OTP_OTP_FUNC_CMD_OTP_PROGRAM, OTP_OTP_FUNC_CMD(otp->base));
writel(OTP_OTP_CMD_GO_OTP_GO, OTP_OTP_CMD_GO(otp->base));
rc = lan9662_otp_execute(otp);
if (!rc) {
pass = readl(OTP_OTP_PASS_FAIL(otp->base));
if (pass & OTP_OTP_PASS_FAIL_OTP_WRITE_PROHIBITED)
return -EACCES;
if (pass & OTP_OTP_PASS_FAIL_OTP_FAIL)
return -EIO;
}
return rc;
}
static int lan9662_otp_read(void *context, unsigned int offset,
void *_val, size_t bytes)
{
struct lan9662_otp *otp = context;
u8 *val = _val;
uint8_t data;
int i, rc = 0;
lan9662_otp_power(otp, true);
for (i = 0; i < bytes; i++) {
rc = lan9662_otp_read_byte(otp, offset + i, &data);
if (rc < 0)
break;
*val++ = data;
}
lan9662_otp_power(otp, false);
return rc;
}
static int lan9662_otp_write(void *context, unsigned int offset,
void *_val, size_t bytes)
{
struct lan9662_otp *otp = context;
u8 *val = _val;
u8 data, newdata;
int i, rc = 0;
lan9662_otp_power(otp, true);
for (i = 0; i < bytes; i++) {
/* Skip zero bytes */
if (val[i]) {
rc = lan9662_otp_read_byte(otp, offset + i, &data);
if (rc < 0)
break;
newdata = data | val[i];
if (newdata == data)
continue;
rc = lan9662_otp_write_byte(otp, offset + i,
newdata);
if (rc < 0)
break;
}
}
lan9662_otp_power(otp, false);
return rc;
}
static struct nvmem_config otp_config = {
.name = "lan9662-otp",
.stride = 1,
.word_size = 1,
.reg_read = lan9662_otp_read,
.reg_write = lan9662_otp_write,
.size = OTP_MEM_SIZE,
};
static int lan9662_otp_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct nvmem_device *nvmem;
struct lan9662_otp *otp;
otp = devm_kzalloc(&pdev->dev, sizeof(*otp), GFP_KERNEL);
if (!otp)
return -ENOMEM;
otp->dev = dev;
otp->base = devm_platform_ioremap_resource(pdev, 0);
if (IS_ERR(otp->base))
return PTR_ERR(otp->base);
otp_config.priv = otp;
otp_config.dev = dev;
nvmem = devm_nvmem_register(dev, &otp_config);
return PTR_ERR_OR_ZERO(nvmem);
}
static const struct of_device_id lan9662_otp_match[] = {
{ .compatible = "microchip,lan9662-otp", },
{ },
};
MODULE_DEVICE_TABLE(of, lan9662_otp_match);
static struct platform_driver lan9662_otp_driver = {
.probe = lan9662_otp_probe,
.driver = {
.name = "lan9662-otp",
.of_match_table = lan9662_otp_match,
},
};
module_platform_driver(lan9662_otp_driver);
MODULE_AUTHOR("Horatiu Vultur <horatiu.vultur@microchip.com>");
MODULE_DESCRIPTION("lan9662 OTP driver");
MODULE_LICENSE("GPL");
|
