[linux-2.6-block.git] / drivers / char / hw_random / octeon-rng.c

/*
 * Hardware Random Number Generator support for Cavium Networks
 * Octeon processor family.
 *
 * This file is subject to the terms and conditions of the GNU General Public
 * License.  See the file "COPYING" in the main directory of this archive
 * for more details.
 *
 * Copyright (C) 2009 Cavium Networks
 */

#include <linux/module.h>
#include <linux/platform_device.h>
#include <linux/device.h>
#include <linux/hw_random.h>
#include <linux/io.h>
#include <linux/gfp.h>

#include <asm/octeon/octeon.h>
#include <asm/octeon/cvmx-rnm-defs.h>

struct octeon_rng {
	struct hwrng ops;
	void __iomem *control_status;
	void __iomem *result;
};

static int octeon_rng_init(struct hwrng *rng)
{
	union cvmx_rnm_ctl_status ctl;
	struct octeon_rng *p = container_of(rng, struct octeon_rng, ops);

	ctl.u64 = 0;
	ctl.s.ent_en = 1; /* Enable the entropy source.  */
	ctl.s.rng_en = 1; /* Enable the RNG hardware.  */
	cvmx_write_csr((u64)p->control_status, ctl.u64);
	return 0;
}

static void octeon_rng_cleanup(struct hwrng *rng)
{
	union cvmx_rnm_ctl_status ctl;
	struct octeon_rng *p = container_of(rng, struct octeon_rng, ops);

	ctl.u64 = 0;
	/* Disable everything.  */
	cvmx_write_csr((u64)p->control_status, ctl.u64);
}

static int octeon_rng_data_read(struct hwrng *rng, u32 *data)
{
	struct octeon_rng *p = container_of(rng, struct octeon_rng, ops);

	*data = cvmx_read64_uint32((u64)p->result);
	return sizeof(u32);
}

static int octeon_rng_probe(struct platform_device *pdev)
{
	struct resource *res_ports;
	struct resource *res_result;
	struct octeon_rng *rng;
	int ret;
	struct hwrng ops = {
		.name = "octeon",
		.init = octeon_rng_init,
		.cleanup = octeon_rng_cleanup,
		.data_read = octeon_rng_data_read
	};

	rng = devm_kzalloc(&pdev->dev, sizeof(*rng), GFP_KERNEL);
	if (!rng)
		return -ENOMEM;

	res_ports = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	if (!res_ports)
		return -ENOENT;

	res_result = platform_get_resource(pdev, IORESOURCE_MEM, 1);
	if (!res_result)
		return -ENOENT;


	rng->control_status = devm_ioremap_nocache(&pdev->dev,
						   res_ports->start,
						   sizeof(u64));
	if (!rng->control_status)
		return -ENOENT;

	rng->result = devm_ioremap_nocache(&pdev->dev,
					   res_result->start,
					   sizeof(u64));
	if (!rng->result)
		return -ENOENT;

	rng->ops = ops;

	platform_set_drvdata(pdev, &rng->ops);
	ret = hwrng_register(&rng->ops);
	if (ret)
		return -ENOENT;

	dev_info(&pdev->dev, "Octeon Random Number Generator\n");

	return 0;
}

static int octeon_rng_remove(struct platform_device *pdev)
{
	struct hwrng *rng = platform_get_drvdata(pdev);

	hwrng_unregister(rng);

	return 0;
}

static struct platform_driver octeon_rng_driver = {
	.driver = {
		.name		= "octeon_rng",
	},
	.probe		= octeon_rng_probe,
	.remove		= octeon_rng_remove,
};

module_platform_driver(octeon_rng_driver);

MODULE_AUTHOR("David Daney");
MODULE_LICENSE("GPL");
Commit	Line	Data
f7557dc8 DD	1	/*
	2	* Hardware Random Number Generator support for Cavium Networks
	3	* Octeon processor family.
	4	*
	5	* This file is subject to the terms and conditions of the GNU General Public
	6	* License. See the file "COPYING" in the main directory of this archive
	7	* for more details.
	8	*
	9	* Copyright (C) 2009 Cavium Networks
	10	*/
	11
	12	#include <linux/module.h>
f7557dc8 DD	13	#include <linux/platform_device.h>
	14	#include <linux/device.h>
	15	#include <linux/hw_random.h>
	16	#include <linux/io.h>
5a0e3ad6	17	#include <linux/gfp.h>
f7557dc8 DD	18
	19	#include <asm/octeon/octeon.h>
	20	#include <asm/octeon/cvmx-rnm-defs.h>
	21
	22	struct octeon_rng {
	23	struct hwrng ops;
	24	void __iomem *control_status;
	25	void __iomem *result;
	26	};
	27
	28	static int octeon_rng_init(struct hwrng *rng)
	29	{
	30	union cvmx_rnm_ctl_status ctl;
	31	struct octeon_rng *p = container_of(rng, struct octeon_rng, ops);
	32
	33	ctl.u64 = 0;
	34	ctl.s.ent_en = 1; /* Enable the entropy source. */
	35	ctl.s.rng_en = 1; /* Enable the RNG hardware. */
	36	cvmx_write_csr((u64)p->control_status, ctl.u64);
	37	return 0;
	38	}
	39
	40	static void octeon_rng_cleanup(struct hwrng *rng)
	41	{
	42	union cvmx_rnm_ctl_status ctl;
	43	struct octeon_rng *p = container_of(rng, struct octeon_rng, ops);
	44
	45	ctl.u64 = 0;
	46	/* Disable everything. */
	47	cvmx_write_csr((u64)p->control_status, ctl.u64);
	48	}
	49
	50	static int octeon_rng_data_read(struct hwrng rng, u32 data)
	51	{
	52	struct octeon_rng *p = container_of(rng, struct octeon_rng, ops);
	53
	54	*data = cvmx_read64_uint32((u64)p->result);
	55	return sizeof(u32);
	56	}
	57
bcd2982a	58	static int octeon_rng_probe(struct platform_device *pdev)
f7557dc8 DD	59	{
	60	struct resource *res_ports;
	61	struct resource *res_result;
	62	struct octeon_rng *rng;
	63	int ret;
	64	struct hwrng ops = {
	65	.name = "octeon",
	66	.init = octeon_rng_init,
	67	.cleanup = octeon_rng_cleanup,
	68	.data_read = octeon_rng_data_read
	69	};
	70
	71	rng = devm_kzalloc(&pdev->dev, sizeof(*rng), GFP_KERNEL);
	72	if (!rng)
	73	return -ENOMEM;
	74
	75	res_ports = platform_get_resource(pdev, IORESOURCE_MEM, 0);
	76	if (!res_ports)
4dbb845d	77	return -ENOENT;
f7557dc8 DD	78
	79	res_result = platform_get_resource(pdev, IORESOURCE_MEM, 1);
	80	if (!res_result)
4dbb845d	81	return -ENOENT;
f7557dc8 DD	82
	83
	84	rng->control_status = devm_ioremap_nocache(&pdev->dev,
	85	res_ports->start,
	86	sizeof(u64));
	87	if (!rng->control_status)
4dbb845d	88	return -ENOENT;
f7557dc8 DD	89
	90	rng->result = devm_ioremap_nocache(&pdev->dev,
	91	res_result->start,
	92	sizeof(u64));
	93	if (!rng->result)
4dbb845d	94	return -ENOENT;
f7557dc8 DD	95
	96	rng->ops = ops;
	97
1f539bcb	98	platform_set_drvdata(pdev, &rng->ops);
f7557dc8 DD	99	ret = hwrng_register(&rng->ops);
f7557dc8 DD	100	if (ret)
4dbb845d	101	return -ENOENT;
f7557dc8 DD	102
	103	dev_info(&pdev->dev, "Octeon Random Number Generator\n");
	104
	105	return 0;
f7557dc8 DD	106	}
f7557dc8 DD	107
87094a04	108	static int octeon_rng_remove(struct platform_device *pdev)
f7557dc8	109	{
1f539bcb	110	struct hwrng *rng = platform_get_drvdata(pdev);
f7557dc8 DD	111
	112	hwrng_unregister(rng);
	113
	114	return 0;
	115	}
	116
	117	static struct platform_driver octeon_rng_driver = {
	118	.driver = {
	119	.name = "octeon_rng",
f7557dc8 DD	120	},
f7557dc8 DD	121	.probe = octeon_rng_probe,
87094a04	122	.remove = octeon_rng_remove,
f7557dc8 DD	123	};
f7557dc8 DD	124
b21cb324	125	module_platform_driver(octeon_rng_driver);
f7557dc8 DD	126
	127	MODULE_AUTHOR("David Daney");
	128	MODULE_LICENSE("GPL");