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_regs.h>
18 struct bcm63xx_rng_priv {
23 #define to_rng_priv(rng) ((struct bcm63xx_rng_priv *)rng->priv)
25 static int bcm63xx_rng_init(struct hwrng *rng)
27 struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
30 val = __raw_readl(priv->regs + RNG_CTRL);
32 __raw_writel(val, priv->regs + RNG_CTRL);
37 static void bcm63xx_rng_cleanup(struct hwrng *rng)
39 struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
42 val = __raw_readl(priv->regs + RNG_CTRL);
44 __raw_writel(val, priv->regs + RNG_CTRL);
47 static int bcm63xx_rng_data_present(struct hwrng *rng, int wait)
49 struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
51 return __raw_readl(priv->regs + RNG_STAT) & RNG_AVAIL_MASK;
54 static int bcm63xx_rng_data_read(struct hwrng *rng, u32 *data)
56 struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
58 *data = __raw_readl(priv->regs + RNG_DATA);
63 static int bcm63xx_rng_probe(struct platform_device *pdev)
68 struct bcm63xx_rng_priv *priv;
71 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
73 dev_err(&pdev->dev, "no iomem resource\n");
78 priv = kzalloc(sizeof(*priv), GFP_KERNEL);
80 dev_err(&pdev->dev, "no memory for private structure\n");
85 rng = kzalloc(sizeof(*rng), GFP_KERNEL);
87 dev_err(&pdev->dev, "no memory for rng structure\n");
92 platform_set_drvdata(pdev, rng);
93 rng->priv = (unsigned long)priv;
94 rng->name = pdev->name;
95 rng->init = bcm63xx_rng_init;
96 rng->cleanup = bcm63xx_rng_cleanup;
97 rng->data_present = bcm63xx_rng_data_present;
98 rng->data_read = bcm63xx_rng_data_read;
100 clk = clk_get(&pdev->dev, "ipsec");
102 dev_err(&pdev->dev, "no clock for device\n");
109 if (!devm_request_mem_region(&pdev->dev, r->start,
110 resource_size(r), pdev->name)) {
111 dev_err(&pdev->dev, "request mem failed");
116 priv->regs = devm_ioremap_nocache(&pdev->dev, r->start,
119 dev_err(&pdev->dev, "ioremap failed");
126 ret = hwrng_register(rng);
128 dev_err(&pdev->dev, "failed to register rng device\n");
129 goto out_clk_disable;
132 dev_info(&pdev->dev, "registered RNG driver\n");
146 static int bcm63xx_rng_remove(struct platform_device *pdev)
148 struct hwrng *rng = platform_get_drvdata(pdev);
149 struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
151 hwrng_unregister(rng);
152 clk_disable(priv->clk);
159 static struct platform_driver bcm63xx_rng_driver = {
160 .probe = bcm63xx_rng_probe,
161 .remove = bcm63xx_rng_remove,
163 .name = "bcm63xx-rng",
167 module_platform_driver(bcm63xx_rng_driver);
169 MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
170 MODULE_DESCRIPTION("Broadcom BCM63xx RNG driver");
171 MODULE_LICENSE("GPL");