Orange Pi5 kernel

// 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_probe(struct platform_device *pdev)
{
<------>int rc;
 
<------>rc = devm_hwrng_register(&pdev->dev, &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,
};
module_platform_driver(powernv_rng_driver);
 
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Bare metal HWRNG driver for POWER7+ and above");