linux_dsm_epyc7002/drivers/char/hw_random/powernv-rng.c
Thomas Gleixner 2874c5fd28 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 152
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license as published by
  the free software foundation either version 2 of the license or at
  your option any later version

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 3029 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070032.746973796@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-05-30 11:26:32 -07:00

79 lines
1.6 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright 2013 Michael Ellerman, Guo Chao, IBM Corp.
*/
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/mod_devicetable.h>
#include <linux/kernel.h>
#include <linux/platform_device.h>
#include <linux/random.h>
#include <linux/hw_random.h>
static int powernv_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)
{
unsigned long *buf;
int i, len;
/* We rely on rng_buffer_size() being >= sizeof(unsigned long) */
len = max / sizeof(unsigned long);
buf = (unsigned long *)data;
for (i = 0; i < len; i++)
powernv_get_random_long(buf++);
return len * sizeof(unsigned long);
}
static struct hwrng powernv_hwrng = {
.name = "powernv-rng",
.read = powernv_rng_read,
};
static int powernv_rng_remove(struct platform_device *pdev)
{
hwrng_unregister(&powernv_hwrng);
return 0;
}
static int powernv_rng_probe(struct platform_device *pdev)
{
int rc;
rc = hwrng_register(&powernv_hwrng);
if (rc) {
/* We only register one device, ignore any others */
if (rc == -EEXIST)
rc = -ENODEV;
return rc;
}
pr_info("Registered powernv hwrng.\n");
return 0;
}
static const struct of_device_id powernv_rng_match[] = {
{ .compatible = "ibm,power-rng",},
{},
};
MODULE_DEVICE_TABLE(of, powernv_rng_match);
static struct platform_driver powernv_rng_driver = {
.driver = {
.name = "powernv_rng",
.of_match_table = powernv_rng_match,
},
.probe = powernv_rng_probe,
.remove = powernv_rng_remove,
};
module_platform_driver(powernv_rng_driver);
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Bare metal HWRNG driver for POWER7+ and above");