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
|
/*
* Copyright (c) 2015 Pengutronix, Steffen Trumtrar <kernel@pengutronix.de>
* Copyright (c) 2017 Pengutronix, Oleksij Rempel <kernel@pengutronix.de>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2
* as published by the Free Software Foundation.
*/
#include <linux/mfd/syscon.h>
#include <linux/module.h>
#include <linux/nvmem-provider.h>
#include <linux/of_device.h>
#include <linux/regmap.h>
#define IMX6Q_SNVS_HPLR 0x00
#define IMX6Q_SNVS_LPLR 0x34
#define IMX6Q_SNVS_LPGPR 0x68
#define IMX7D_SNVS_HPLR 0x00
#define IMX7D_SNVS_LPLR 0x34
#define IMX7D_SNVS_LPGPR 0x90
#define IMX_GPR_SL BIT(5)
#define IMX_GPR_HL BIT(5)
struct snvs_lpgpr_cfg {
int offset;
int offset_hplr;
int offset_lplr;
int size;
};
struct snvs_lpgpr_priv {
struct device_d *dev;
struct regmap *regmap;
struct nvmem_config cfg;
const struct snvs_lpgpr_cfg *dcfg;
};
static const struct snvs_lpgpr_cfg snvs_lpgpr_cfg_imx6q = {
.offset = IMX6Q_SNVS_LPGPR,
.offset_hplr = IMX6Q_SNVS_HPLR,
.offset_lplr = IMX6Q_SNVS_LPLR,
.size = 4,
};
static const struct snvs_lpgpr_cfg snvs_lpgpr_cfg_imx7d = {
.offset = IMX7D_SNVS_LPGPR,
.offset_hplr = IMX7D_SNVS_HPLR,
.offset_lplr = IMX7D_SNVS_LPLR,
.size = 16,
};
static int snvs_lpgpr_write(void *context, unsigned int offset, void *val,
size_t bytes)
{
struct snvs_lpgpr_priv *priv = context;
const struct snvs_lpgpr_cfg *dcfg = priv->dcfg;
unsigned int lock_reg;
int ret;
ret = regmap_read(priv->regmap, dcfg->offset_hplr, &lock_reg);
if (ret < 0)
return ret;
if (lock_reg & IMX_GPR_SL)
return -EPERM;
ret = regmap_read(priv->regmap, dcfg->offset_lplr, &lock_reg);
if (ret < 0)
return ret;
if (lock_reg & IMX_GPR_HL)
return -EPERM;
return regmap_bulk_write(priv->regmap, dcfg->offset + offset, val,
bytes / 4);
}
static int snvs_lpgpr_read(void *context, unsigned int offset, void *val,
size_t bytes)
{
struct snvs_lpgpr_priv *priv = context;
const struct snvs_lpgpr_cfg *dcfg = priv->dcfg;
return regmap_bulk_read(priv->regmap, dcfg->offset + offset,
val, bytes / 4);
}
static int snvs_lpgpr_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *node = dev->of_node;
struct device_node *syscon_node;
struct snvs_lpgpr_priv *priv;
struct nvmem_config *cfg;
struct nvmem_device *nvmem;
const struct snvs_lpgpr_cfg *dcfg;
if (!node)
return -ENOENT;
priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
dcfg = of_device_get_match_data(dev);
if (!dcfg)
return -EINVAL;
syscon_node = of_get_parent(node);
if (!syscon_node)
return -ENODEV;
priv->regmap = syscon_node_to_regmap(syscon_node);
of_node_put(syscon_node);
if (IS_ERR(priv->regmap))
return PTR_ERR(priv->regmap);
priv->dcfg = dcfg;
cfg = &priv->cfg;
cfg->priv = priv;
cfg->name = dev_name(dev);
cfg->dev = dev;
cfg->stride = 4;
cfg->word_size = 4;
cfg->size = dcfg->size,
cfg->owner = THIS_MODULE;
cfg->reg_read = snvs_lpgpr_read;
cfg->reg_write = snvs_lpgpr_write;
nvmem = devm_nvmem_register(dev, cfg);
return PTR_ERR_OR_ZERO(nvmem);
}
static const struct of_device_id snvs_lpgpr_dt_ids[] = {
{ .compatible = "fsl,imx6q-snvs-lpgpr", .data = &snvs_lpgpr_cfg_imx6q },
{ .compatible = "fsl,imx6ul-snvs-lpgpr",
.data = &snvs_lpgpr_cfg_imx6q },
{ .compatible = "fsl,imx7d-snvs-lpgpr", .data = &snvs_lpgpr_cfg_imx7d },
{ },
};
MODULE_DEVICE_TABLE(of, snvs_lpgpr_dt_ids);
static struct platform_driver snvs_lpgpr_driver = {
.probe = snvs_lpgpr_probe,
.driver = {
.name = "snvs_lpgpr",
.of_match_table = snvs_lpgpr_dt_ids,
},
};
module_platform_driver(snvs_lpgpr_driver);
MODULE_AUTHOR("Oleksij Rempel <o.rempel@pengutronix.de>");
MODULE_DESCRIPTION("Low Power General Purpose Register in i.MX6 and i.MX7 Secure Non-Volatile Storage");
MODULE_LICENSE("GPL v2");
|
