[mirror_ubuntu-artful-kernel.git] / drivers / char / hw_random / cavium-rng-vf.c

/*
 * Hardware Random Number Generator support for Cavium, Inc.
 * Thunder 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) 2016 Cavium, Inc.
 */

#include <linux/hw_random.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/pci.h>
#include <linux/pci_ids.h>

struct cavium_rng {
	struct hwrng ops;
	void __iomem *result;
};

/* Read data from the RNG unit */
static int cavium_rng_read(struct hwrng *rng, void *dat, size_t max, bool wait)
{
	struct cavium_rng *p = container_of(rng, struct cavium_rng, ops);
	unsigned int size = max;

	while (size >= 8) {
		*((u64 *)dat) = readq(p->result);
		size -= 8;
		dat += 8;
	}
	while (size > 0) {
		*((u8 *)dat) = readb(p->result);
		size--;
		dat++;
	}
	return max;
}

/* Map Cavium RNG to an HWRNG object */
static int cavium_rng_probe_vf(struct	pci_dev		*pdev,
			 const struct	pci_device_id	*id)
{
	struct	cavium_rng *rng;
	int	ret;

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

	/* Map the RNG result */
	rng->result = pcim_iomap(pdev, 0, 0);
	if (!rng->result) {
		dev_err(&pdev->dev, "Error iomap failed retrieving result.\n");
		return -ENOMEM;
	}

	rng->ops.name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
				       "cavium-rng-%s", dev_name(&pdev->dev));
	if (!rng->ops.name)
		return -ENOMEM;

	rng->ops.read    = cavium_rng_read;
	rng->ops.quality = 1000;

	pci_set_drvdata(pdev, rng);

	ret = hwrng_register(&rng->ops);
	if (ret) {
		dev_err(&pdev->dev, "Error registering device as HWRNG.\n");
		return ret;
	}

	return 0;
}

/* Remove the VF */
void  cavium_rng_remove_vf(struct pci_dev *pdev)
{
	struct cavium_rng *rng;

	rng = pci_get_drvdata(pdev);
	hwrng_unregister(&rng->ops);
}

static const struct pci_device_id cavium_rng_vf_id_table[] = {
	{ PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, 0xa033), 0, 0, 0},
	{0,},
};
MODULE_DEVICE_TABLE(pci, cavium_rng_vf_id_table);

static struct pci_driver cavium_rng_vf_driver = {
	.name		= "cavium_rng_vf",
	.id_table	= cavium_rng_vf_id_table,
	.probe		= cavium_rng_probe_vf,
	.remove		= cavium_rng_remove_vf,
};
module_pci_driver(cavium_rng_vf_driver);

MODULE_AUTHOR("Omer Khaliq <okhaliq@caviumnetworks.com>");
MODULE_LICENSE("GPL");
Commit	Line	Data
cc2f1908 OK	1	/*
	2	* Hardware Random Number Generator support for Cavium, Inc.
	3	* Thunder 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) 2016 Cavium, Inc.
	10	*/
	11
	12	#include <linux/hw_random.h>
	13	#include <linux/io.h>
	14	#include <linux/module.h>
	15	#include <linux/pci.h>
	16	#include <linux/pci_ids.h>
	17
	18	struct cavium_rng {
	19	struct hwrng ops;
	20	void __iomem *result;
	21	};
	22
	23	/* Read data from the RNG unit */
	24	static int cavium_rng_read(struct hwrng rng, void dat, size_t max, bool wait)
	25	{
	26	struct cavium_rng *p = container_of(rng, struct cavium_rng, ops);
	27	unsigned int size = max;
	28
	29	while (size >= 8) {
	30	((u64 )dat) = readq(p->result);
	31	size -= 8;
	32	dat += 8;
	33	}
	34	while (size > 0) {
	35	((u8 )dat) = readb(p->result);
	36	size--;
	37	dat++;
	38	}
	39	return max;
	40	}
	41
	42	/* Map Cavium RNG to an HWRNG object */
	43	static int cavium_rng_probe_vf(struct pci_dev *pdev,
	44	const struct pci_device_id *id)
	45	{
	46	struct cavium_rng *rng;
	47	int ret;
	48
	49	rng = devm_kzalloc(&pdev->dev, sizeof(*rng), GFP_KERNEL);
	50	if (!rng)
	51	return -ENOMEM;
	52
	53	/* Map the RNG result */
	54	rng->result = pcim_iomap(pdev, 0, 0);
	55	if (!rng->result) {
	56	dev_err(&pdev->dev, "Error iomap failed retrieving result.\n");
	57	return -ENOMEM;
	58	}
	59
87f3d088 DD	60	rng->ops.name = devm_kasprintf(&pdev->dev, GFP_KERNEL,
	61	"cavium-rng-%s", dev_name(&pdev->dev));
	62	if (!rng->ops.name)
	63	return -ENOMEM;
	64
cc2f1908 OK	65	rng->ops.read = cavium_rng_read;
	66	rng->ops.quality = 1000;
	67
	68	pci_set_drvdata(pdev, rng);
	69
	70	ret = hwrng_register(&rng->ops);
	71	if (ret) {
	72	dev_err(&pdev->dev, "Error registering device as HWRNG.\n");
	73	return ret;
	74	}
	75
	76	return 0;
	77	}
	78
	79	/* Remove the VF */
	80	void cavium_rng_remove_vf(struct pci_dev *pdev)
	81	{
	82	struct cavium_rng *rng;
	83
	84	rng = pci_get_drvdata(pdev);
	85	hwrng_unregister(&rng->ops);
	86	}
	87
	88	static const struct pci_device_id cavium_rng_vf_id_table[] = {
	89	{ PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, 0xa033), 0, 0, 0},
	90	{0,},
	91	};
	92	MODULE_DEVICE_TABLE(pci, cavium_rng_vf_id_table);
	93
	94	static struct pci_driver cavium_rng_vf_driver = {
	95	.name = "cavium_rng_vf",
	96	.id_table = cavium_rng_vf_id_table,
	97	.probe = cavium_rng_probe_vf,
	98	.remove = cavium_rng_remove_vf,
	99	};
	100	module_pci_driver(cavium_rng_vf_driver);
	101
	102	MODULE_AUTHOR("Omer Khaliq <okhaliq@caviumnetworks.com>");
	103	MODULE_LICENSE("GPL");