Orange Pi5 kernel

^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  1) // SPDX-License-Identifier: GPL-2.0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  2) /* Copyright (c) 2019 HiSilicon Limited. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  3) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  4) #include <linux/acpi.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  5) #include <linux/err.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  6) #include <linux/hw_random.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  7) #include <linux/io.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  8) #include <linux/iopoll.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300  9) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) #include <linux/module.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) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) #define HISI_TRNG_REG		0x00F0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #define HISI_TRNG_BYTES		4
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #define HISI_TRNG_QUALITY	512
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #define SLEEP_US		10
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #define TIMEOUT_US		10000
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) struct hisi_trng {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) 	void __iomem *base;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) 	struct hwrng rng;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) static int hisi_trng_read(struct hwrng *rng, void *buf, size_t max, bool wait)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) 	struct hisi_trng *trng;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) 	int currsize = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) 	u32 val = 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) 	u32 ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) 	trng = container_of(rng, struct hisi_trng, rng);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) 	do {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) 		ret = readl_poll_timeout(trng->base + HISI_TRNG_REG, val,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) 					 val, SLEEP_US, TIMEOUT_US);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) 		if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) 			return currsize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) 		if (max - currsize >= HISI_TRNG_BYTES) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) 			memcpy(buf + currsize, &val, HISI_TRNG_BYTES);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) 			currsize += HISI_TRNG_BYTES;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) 			if (currsize == max)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) 				return currsize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) 			continue;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) 		}
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) 		/* copy remaining bytes */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) 		memcpy(buf + currsize, &val, max - currsize);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) 		currsize = max;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) 	} while (currsize < max);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) 	return currsize;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) static int hisi_trng_probe(struct platform_device *pdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) 	struct hisi_trng *trng;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) 	int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) 	trng = devm_kzalloc(&pdev->dev, sizeof(*trng), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) 	if (!trng)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) 		return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) 	trng->base = devm_platform_ioremap_resource(pdev, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) 	if (IS_ERR(trng->base))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) 		return PTR_ERR(trng->base);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) 	trng->rng.name = pdev->name;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) 	trng->rng.read = hisi_trng_read;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) 	trng->rng.quality = HISI_TRNG_QUALITY;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) 	ret = devm_hwrng_register(&pdev->dev, &trng->rng);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) 	if (ret)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) 		dev_err(&pdev->dev, "failed to register hwrng!\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) 	return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) static const struct acpi_device_id hisi_trng_acpi_match[] = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) 	{ "HISI02B3", 0 },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) 	{ }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) MODULE_DEVICE_TABLE(acpi, hisi_trng_acpi_match);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) static struct platform_driver hisi_trng_driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87) 	.probe		= hisi_trng_probe,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) 	.driver		= {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) 		.name	= "hisi-trng-v2",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) 		.acpi_match_table = ACPI_PTR(hisi_trng_acpi_match),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) 	},
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) module_platform_driver(hisi_trng_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) 
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) MODULE_LICENSE("GPL v2");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) MODULE_AUTHOR("Weili Qian <qianweili@huawei.com>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) MODULE_AUTHOR("Zaibo Xu <xuzaibo@huawei.com>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) MODULE_DESCRIPTION("HiSilicon true random number generator V2 driver");