Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0-or-later
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3)  * Copyright 2013 Michael Ellerman, Guo Chao, IBM Corp.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4)  */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6) #define pr_fmt(fmt)	KBUILD_MODNAME ": " fmt
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) #include <linux/mod_devicetable.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) #include <linux/platform_device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/random.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/hw_random.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) static int powernv_rng_read(struct hwrng *rng, void *data, size_t max, bool wait)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) 	unsigned long *buf;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) 	int i, len;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) 	/* We rely on rng_buffer_size() being >= sizeof(unsigned long) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 	len = max / sizeof(unsigned long);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) 	buf = (unsigned long *)data;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) 	for (i = 0; i < len; i++)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) 		powernv_get_random_long(buf++);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) 	return len * sizeof(unsigned long);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) static struct hwrng powernv_hwrng = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 	.name = "powernv-rng",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 	.read = powernv_rng_read,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) static int powernv_rng_probe(struct platform_device *pdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 	int rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 	rc = devm_hwrng_register(&pdev->dev, &powernv_hwrng);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) 	if (rc) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 		/* We only register one device, ignore any others */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 		if (rc == -EEXIST)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 			rc = -ENODEV;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 		return rc;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 	}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) 	pr_info("Registered powernv hwrng.\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) 	return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) static const struct of_device_id powernv_rng_match[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) 	{ .compatible	= "ibm,power-rng",},
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) 	{},
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) MODULE_DEVICE_TABLE(of, powernv_rng_match);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) static struct platform_driver powernv_rng_driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) 	.driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) 		.name = "powernv_rng",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 		.of_match_table = powernv_rng_match,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) 	},
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) 	.probe	= powernv_rng_probe,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) module_platform_driver(powernv_rng_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) MODULE_LICENSE("GPL");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) MODULE_DESCRIPTION("Bare metal HWRNG driver for POWER7+ and above");