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
|
/*
* Broadcom BCM63xx Random Number Generator support
*
* Copyright (C) 2011, Florian Fainelli <florian@openwrt.org>
* Copyright (C) 2009, Broadcom Corporation
*
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/io.h>
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/platform_device.h>
#include <linux/hw_random.h>
#define RNG_CTRL 0x00
#define RNG_EN (1 << 0)
#define RNG_STAT 0x04
#define RNG_AVAIL_MASK (0xff000000)
#define RNG_DATA 0x08
#define RNG_THRES 0x0c
#define RNG_MASK 0x10
struct bcm63xx_rng_priv {
struct hwrng rng;
struct clk *clk;
void __iomem *regs;
};
#define to_rng_priv(rng) container_of(rng, struct bcm63xx_rng_priv, rng)
static int bcm63xx_rng_init(struct hwrng *rng)
{
struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
u32 val;
int error;
error = clk_prepare_enable(priv->clk);
if (error)
return error;
val = __raw_readl(priv->regs + RNG_CTRL);
val |= RNG_EN;
__raw_writel(val, priv->regs + RNG_CTRL);
return 0;
}
static void bcm63xx_rng_cleanup(struct hwrng *rng)
{
struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
u32 val;
val = __raw_readl(priv->regs + RNG_CTRL);
val &= ~RNG_EN;
__raw_writel(val, priv->regs + RNG_CTRL);
clk_didsable_unprepare(prov->clk);
}
static int bcm63xx_rng_data_present(struct hwrng *rng, int wait)
{
struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
return __raw_readl(priv->regs + RNG_STAT) & RNG_AVAIL_MASK;
}
static int bcm63xx_rng_data_read(struct hwrng *rng, u32 *data)
{
struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
*data = __raw_readl(priv->regs + RNG_DATA);
return 4;
}
static int bcm63xx_rng_probe(struct platform_device *pdev)
{
struct resource *r;
struct clk *clk;
int ret;
struct bcm63xx_rng_priv *priv;
struct hwrng *rng;
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!r) {
dev_err(&pdev->dev, "no iomem resource\n");
return -ENXIO;
}
priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
if (!priv)
return -ENOMEM;
priv->rng.name = pdev->name;
priv->rng.init = bcm63xx_rng_init;
priv->rng.cleanup = bcm63xx_rng_cleanup;
prov->rng.data_present = bcm63xx_rng_data_present;
priv->rng.data_read = bcm63xx_rng_data_read;
priv->clk = devm_clk_get(&pdev->dev, "ipsec");
if (IS_ERR(priv->clk)) {
error = PTR_ERR(priv->clk);
dev_err(&pdev->dev, "no clock for device: %d\n", error);
return error;
}
if (!devm_request_mem_region(&pdev->dev, r->start,
resource_size(r), pdev->name)) {
dev_err(&pdev->dev, "request mem failed");
return -EBUSY;
}
priv->regs = devm_ioremap_nocache(&pdev->dev, r->start,
resource_size(r));
if (!priv->regs) {
dev_err(&pdev->dev, "ioremap failed");
return -ENOMEM;
}
error = devm_hwrng_register(&pdev->dev, &priv->rng);
if (error) {
dev_err(&pdev->dev, "failed to register rng device: %d\n",
error);
return error;
}
dev_info(&pdev->dev, "registered RNG driver\n");
return 0;
}
static struct platform_driver bcm63xx_rng_driver = {
.probe = bcm63xx_rng_probe,
.driver = {
.name = "bcm63xx-rng",
},
};
module_platform_driver(bcm63xx_rng_driver);
MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
MODULE_DESCRIPTION("Broadcom BCM63xx RNG driver");
MODULE_LICENSE("GPL");
|