^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-only
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Copyright (C) 2016 HiSilicon Co., Ltd.
^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) #include <linux/err.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) #include <linux/kernel.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) #include <linux/hw_random.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) #include <linux/io.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/of.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) #include <linux/platform_device.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) #include <linux/random.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) #define RNG_SEED 0x0
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) #define RNG_CTRL 0x4
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) #define RNG_SEED_SEL BIT(2)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) #define RNG_RING_EN BIT(1)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) #define RNG_EN BIT(0)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) #define RNG_RAN_NUM 0x10
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) #define RNG_PHY_SEED 0x14
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) #define to_hisi_rng(p) container_of(p, struct hisi_rng, rng)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) static int seed_sel;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26) module_param(seed_sel, int, S_IRUGO);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) MODULE_PARM_DESC(seed_sel, "Auto reload seed. 0, use LFSR(default); 1, use ring oscillator.");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) struct hisi_rng {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) void __iomem *base;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) struct hwrng rng;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) static int hisi_rng_init(struct hwrng *rng)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) struct hisi_rng *hrng = to_hisi_rng(rng);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) int val = RNG_EN;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) u32 seed;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) /* get a random number as initial seed */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) get_random_bytes(&seed, sizeof(seed));
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43) writel_relaxed(seed, hrng->base + RNG_SEED);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) /**
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) * The seed is reload periodically, there are two choice
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47) * of seeds, default seed using the value from LFSR, or
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) * will use seed generated by ring oscillator.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) if (seed_sel == 1)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) val |= RNG_RING_EN | RNG_SEED_SEL;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) writel_relaxed(val, hrng->base + RNG_CTRL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) static void hisi_rng_cleanup(struct hwrng *rng)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59) struct hisi_rng *hrng = to_hisi_rng(rng);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) writel_relaxed(0, hrng->base + RNG_CTRL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) static int hisi_rng_read(struct hwrng *rng, void *buf, size_t max, bool wait)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) struct hisi_rng *hrng = to_hisi_rng(rng);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67) u32 *data = buf;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) *data = readl_relaxed(hrng->base + RNG_RAN_NUM);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70) return 4;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) static int hisi_rng_probe(struct platform_device *pdev)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) struct hisi_rng *rng;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) int ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78) rng = devm_kzalloc(&pdev->dev, sizeof(*rng), GFP_KERNEL);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) if (!rng)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) return -ENOMEM;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) platform_set_drvdata(pdev, rng);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84) rng->base = devm_platform_ioremap_resource(pdev, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) if (IS_ERR(rng->base))
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) return PTR_ERR(rng->base);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) rng->rng.name = pdev->name;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) rng->rng.init = hisi_rng_init;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) rng->rng.cleanup = hisi_rng_cleanup;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91) rng->rng.read = hisi_rng_read;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93) ret = devm_hwrng_register(&pdev->dev, &rng->rng);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) if (ret) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) dev_err(&pdev->dev, "failed to register hwrng\n");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) return ret;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) return 0;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) static const struct of_device_id hisi_rng_dt_ids[] __maybe_unused = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103) { .compatible = "hisilicon,hip04-rng" },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) { .compatible = "hisilicon,hip05-rng" },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) { }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) MODULE_DEVICE_TABLE(of, hisi_rng_dt_ids);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) static struct platform_driver hisi_rng_driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) .probe = hisi_rng_probe,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) .driver = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112) .name = "hisi-rng",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) .of_match_table = of_match_ptr(hisi_rng_dt_ids),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) },
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) module_platform_driver(hisi_rng_driver);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) MODULE_LICENSE("GPL");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) MODULE_AUTHOR("Kefeng Wang <wangkefeng.wang@huawei>");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) MODULE_DESCRIPTION("Hisilicon random number generator driver");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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