[deliverable/linux.git] / drivers / char / hw_random / bcm63xx-rng.c

/*
 * 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 clk *clk;
	void __iomem *regs;
};

#define to_rng_priv(rng)	((struct bcm63xx_rng_priv *)rng->priv)

static int bcm63xx_rng_init(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);

	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);
}

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");
		ret = -ENXIO;
		goto out;
	}

	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
	if (!priv) {
		dev_err(&pdev->dev, "no memory for private structure\n");
		ret = -ENOMEM;
		goto out;
	}

	rng = kzalloc(sizeof(*rng), GFP_KERNEL);
	if (!rng) {
		dev_err(&pdev->dev, "no memory for rng structure\n");
		ret = -ENOMEM;
		goto out_free_priv;
	}

	platform_set_drvdata(pdev, rng);
	rng->priv = (unsigned long)priv;
	rng->name = pdev->name;
	rng->init = bcm63xx_rng_init;
	rng->cleanup = bcm63xx_rng_cleanup;
	rng->data_present = bcm63xx_rng_data_present;
	rng->data_read = bcm63xx_rng_data_read;

	clk = clk_get(&pdev->dev, "ipsec");
	if (IS_ERR(clk)) {
		dev_err(&pdev->dev, "no clock for device\n");
		ret = PTR_ERR(clk);
		goto out_free_rng;
	}

	priv->clk = clk;

	if (!devm_request_mem_region(&pdev->dev, r->start,
					resource_size(r), pdev->name)) {
		dev_err(&pdev->dev, "request mem failed");
		ret = -ENOMEM;
		goto out_free_rng;
	}

	priv->regs = devm_ioremap_nocache(&pdev->dev, r->start,
					resource_size(r));
	if (!priv->regs) {
		dev_err(&pdev->dev, "ioremap failed");
		ret = -ENOMEM;
		goto out_free_rng;
	}

	clk_enable(clk);

	ret = hwrng_register(rng);
	if (ret) {
		dev_err(&pdev->dev, "failed to register rng device\n");
		goto out_clk_disable;
	}

	dev_info(&pdev->dev, "registered RNG driver\n");

	return 0;

out_clk_disable:
	clk_disable(clk);
out_free_rng:
	kfree(rng);
out_free_priv:
	kfree(priv);
out:
	return ret;
}

static int bcm63xx_rng_remove(struct platform_device *pdev)
{
	struct hwrng *rng = platform_get_drvdata(pdev);
	struct bcm63xx_rng_priv *priv = to_rng_priv(rng);

	hwrng_unregister(rng);
	clk_disable(priv->clk);
	kfree(priv);
	kfree(rng);

	return 0;
}

static struct platform_driver bcm63xx_rng_driver = {
	.probe		= bcm63xx_rng_probe,
	.remove		= bcm63xx_rng_remove,
	.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");
Commit	Line	Data
553072b2 FF	1	/*
	2	* Broadcom BCM63xx Random Number Generator support
	3	*
	4	* Copyright (C) 2011, Florian Fainelli <florian@openwrt.org>
	5	* Copyright (C) 2009, Broadcom Corporation
	6	*
	7	*/
	8	#include <linux/module.h>
	9	#include <linux/slab.h>
	10	#include <linux/io.h>
	11	#include <linux/err.h>
	12	#include <linux/clk.h>
	13	#include <linux/platform_device.h>
	14	#include <linux/hw_random.h>
	15
b515e0f9 FF	16	#define RNG_CTRL 0x00
	17	#define RNG_EN (1 << 0)
	18
	19	#define RNG_STAT 0x04
	20	#define RNG_AVAIL_MASK (0xff000000)
	21
	22	#define RNG_DATA 0x08
	23	#define RNG_THRES 0x0c
	24	#define RNG_MASK 0x10
553072b2 FF	25
	26	struct bcm63xx_rng_priv {
	27	struct clk *clk;
	28	void __iomem *regs;
	29	};
	30
	31	#define to_rng_priv(rng) ((struct bcm63xx_rng_priv *)rng->priv)
	32
	33	static int bcm63xx_rng_init(struct hwrng *rng)
	34	{
	35	struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
	36	u32 val;
	37
f7591fae	38	val = __raw_readl(priv->regs + RNG_CTRL);
553072b2	39	val \|= RNG_EN;
f7591fae	40	__raw_writel(val, priv->regs + RNG_CTRL);
553072b2 FF	41
	42	return 0;
	43	}
	44
	45	static void bcm63xx_rng_cleanup(struct hwrng *rng)
	46	{
	47	struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
	48	u32 val;
	49
f7591fae	50	val = __raw_readl(priv->regs + RNG_CTRL);
553072b2	51	val &= ~RNG_EN;
f7591fae	52	__raw_writel(val, priv->regs + RNG_CTRL);
553072b2 FF	53	}
	54
	55	static int bcm63xx_rng_data_present(struct hwrng *rng, int wait)
	56	{
	57	struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
	58
f7591fae	59	return __raw_readl(priv->regs + RNG_STAT) & RNG_AVAIL_MASK;
553072b2 FF	60	}
	61
	62	static int bcm63xx_rng_data_read(struct hwrng rng, u32 data)
	63	{
	64	struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
	65
f7591fae	66	*data = __raw_readl(priv->regs + RNG_DATA);
553072b2 FF	67
	68	return 4;
	69	}
	70
bcd2982a	71	static int bcm63xx_rng_probe(struct platform_device *pdev)
553072b2 FF	72	{
	73	struct resource *r;
	74	struct clk *clk;
	75	int ret;
	76	struct bcm63xx_rng_priv *priv;
	77	struct hwrng *rng;
	78
	79	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	80	if (!r) {
	81	dev_err(&pdev->dev, "no iomem resource\n");
	82	ret = -ENXIO;
	83	goto out;
	84	}
	85
	86	priv = kzalloc(sizeof(*priv), GFP_KERNEL);
	87	if (!priv) {
	88	dev_err(&pdev->dev, "no memory for private structure\n");
	89	ret = -ENOMEM;
	90	goto out;
	91	}
	92
	93	rng = kzalloc(sizeof(*rng), GFP_KERNEL);
	94	if (!rng) {
	95	dev_err(&pdev->dev, "no memory for rng structure\n");
	96	ret = -ENOMEM;
	97	goto out_free_priv;
	98	}
	99
	100	platform_set_drvdata(pdev, rng);
	101	rng->priv = (unsigned long)priv;
	102	rng->name = pdev->name;
	103	rng->init = bcm63xx_rng_init;
	104	rng->cleanup = bcm63xx_rng_cleanup;
	105	rng->data_present = bcm63xx_rng_data_present;
	106	rng->data_read = bcm63xx_rng_data_read;
	107
	108	clk = clk_get(&pdev->dev, "ipsec");
	109	if (IS_ERR(clk)) {
	110	dev_err(&pdev->dev, "no clock for device\n");
	111	ret = PTR_ERR(clk);
	112	goto out_free_rng;
	113	}
	114
	115	priv->clk = clk;
	116
	117	if (!devm_request_mem_region(&pdev->dev, r->start,
	118	resource_size(r), pdev->name)) {
	119	dev_err(&pdev->dev, "request mem failed");
	120	ret = -ENOMEM;
	121	goto out_free_rng;
	122	}
	123
	124	priv->regs = devm_ioremap_nocache(&pdev->dev, r->start,
	125	resource_size(r));
	126	if (!priv->regs) {
	127	dev_err(&pdev->dev, "ioremap failed");
	128	ret = -ENOMEM;
	129	goto out_free_rng;
	130	}
	131
	132	clk_enable(clk);
	133
	134	ret = hwrng_register(rng);
	135	if (ret) {
136	dev_err(&pdev->dev, "failed to register rng device\n");
137	goto out_clk_disable;
138	}
139
140	dev_info(&pdev->dev, "registered RNG driver\n");
141
142	return 0;
143
144	out_clk_disable:
145	clk_disable(clk);
146	out_free_rng:
553072b2 FF	147	kfree(rng);
	148	out_free_priv:
	149	kfree(priv);
	150	out:
	151	return ret;
	152	}
	153
39af33fc	154	static int bcm63xx_rng_remove(struct platform_device *pdev)
553072b2 FF	155	{
	156	struct hwrng *rng = platform_get_drvdata(pdev);
	157	struct bcm63xx_rng_priv *priv = to_rng_priv(rng);
	158
	159	hwrng_unregister(rng);
	160	clk_disable(priv->clk);
	161	kfree(priv);
	162	kfree(rng);
553072b2 FF	163
	164	return 0;
	165	}
	166
	167	static struct platform_driver bcm63xx_rng_driver = {
	168	.probe = bcm63xx_rng_probe,
bcd2982a	169	.remove = bcm63xx_rng_remove,
553072b2 FF	170	.driver = {
553072b2 FF	171	.name = "bcm63xx-rng",
553072b2 FF	172	},
	173	};
	174
	175	module_platform_driver(bcm63xx_rng_driver);
	176
	177	MODULE_AUTHOR("Florian Fainelli <florian@openwrt.org>");
	178	MODULE_DESCRIPTION("Broadcom BCM63xx RNG driver");
	179	MODULE_LICENSE("GPL");