2 * Broadcom BCM63xx Random Number Generator support
4 * Copyright (C) 2011, Florian Fainelli <florian@openwrt.org>
5 * Copyright (C) 2009, Broadcom Corporation
8 #include <linux/module.h>
9 #include <linux/slab.h>
11 #include <linux/err.h>
12 #include <linux/clk.h>
13 #include <linux/platform_device.h>
14 #include <linux/hw_random.h>
16 #include <bcm63xx_io.h>
17 #include <bcm63xx_regs.h>
19 struct bcm63xx_rng_priv {
24 #define to_rng_priv(rng) ((struct bcm63xx_rng_priv *)rng->priv)
26 static int bcm63xx_rng_init(struct hwrng *rng)
28 struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
31 val = bcm_readl(priv->regs + RNG_CTRL);
33 bcm_writel(val, priv->regs + RNG_CTRL);
38 static void bcm63xx_rng_cleanup(struct hwrng *rng)
40 struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
43 val = bcm_readl(priv->regs + RNG_CTRL);
45 bcm_writel(val, priv->regs + RNG_CTRL);
48 static int bcm63xx_rng_data_present(struct hwrng *rng, int wait)
50 struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
52 return bcm_readl(priv->regs + RNG_STAT) & RNG_AVAIL_MASK;
55 static int bcm63xx_rng_data_read(struct hwrng *rng, u32 *data)
57 struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
59 *data = bcm_readl(priv->regs + RNG_DATA);
64 static int bcm63xx_rng_probe(struct platform_device *pdev)
69 struct bcm63xx_rng_priv *priv;
72 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
74 dev_err(&pdev->dev, "no iomem resource\n");
79 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
81 dev_err(&pdev->dev, "no memory for private structure\n");
86 rng = kzalloc(sizeof(*rng), GFP_KERNEL);
88 dev_err(&pdev->dev, "no memory for rng structure\n");
93 platform_set_drvdata(pdev, rng);
94 rng->priv = (unsigned long)priv;
95 rng->name = pdev->name;
96 rng->init = bcm63xx_rng_init;
97 rng->cleanup = bcm63xx_rng_cleanup;
98 rng->data_present = bcm63xx_rng_data_present;
99 rng->data_read = bcm63xx_rng_data_read;
101 clk = clk_get(&pdev->dev, "ipsec");
103 dev_err(&pdev->dev, "no clock for device\n");
110 if (!devm_request_mem_region(&pdev->dev, r->start,
111 resource_size(r), pdev->name)) {
112 dev_err(&pdev->dev, "request mem failed");
117 priv->regs = devm_ioremap_nocache(&pdev->dev, r->start,
120 dev_err(&pdev->dev, "ioremap failed");
127 ret = hwrng_register(rng);
129 dev_err(&pdev->dev, "failed to register rng device\n");
130 goto out_clk_disable;
133 dev_info(&pdev->dev, "registered RNG driver\n");
147 static int bcm63xx_rng_remove(struct platform_device *pdev)
149 struct hwrng *rng = platform_get_drvdata(pdev);
150 struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
152 hwrng_unregister(rng);
153 clk_disable(priv->clk);
160 static struct platform_driver bcm63xx_rng_driver = {
161 .probe = bcm63xx_rng_probe,
162 .remove = bcm63xx_rng_remove,
164 .name = "bcm63xx-rng",
168 module_platform_driver(bcm63xx_rng_driver);
170 MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
171 MODULE_DESCRIPTION("Broadcom BCM63xx RNG driver");
172 MODULE_LICENSE("GPL");