119 lines
2.7 KiB
C
119 lines
2.7 KiB
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((unsigned long)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((unsigned long)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((unsigned long)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(&pdev->dev,
|
|
res_ports->start,
|
|
sizeof(u64));
|
|
if (!rng->control_status)
|
|
return -ENOENT;
|
|
|
|
rng->result = devm_ioremap(&pdev->dev,
|
|
res_result->start,
|
|
sizeof(u64));
|
|
if (!rng->result)
|
|
return -ENOENT;
|
|
|
|
rng->ops = ops;
|
|
|
|
platform_set_drvdata(pdev, &rng->ops);
|
|
ret = devm_hwrng_register(&pdev->dev, &rng->ops);
|
|
if (ret)
|
|
return -ENOENT;
|
|
|
|
dev_info(&pdev->dev, "Octeon Random Number Generator\n");
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct platform_driver octeon_rng_driver = {
|
|
.driver = {
|
|
.name = "octeon_rng",
|
|
},
|
|
.probe = octeon_rng_probe,
|
|
};
|
|
|
|
module_platform_driver(octeon_rng_driver);
|
|
|
|
MODULE_AUTHOR("David Daney");
|
|
MODULE_LICENSE("GPL");
|