From a2216e1874715a8b4a6f4da2ddbe9277e5613c49 Mon Sep 17 00:00:00 2001 From: David Yang Date: Sun, 2 Apr 2023 00:44:40 +0800 Subject: crypto: hisilicon/trng - add support for HiSTB TRNG HiSTB TRNG are found on some HiSilicon STB SoCs. Signed-off-by: David Yang Signed-off-by: Herbert Xu --- drivers/crypto/hisilicon/Kconfig | 7 ++ drivers/crypto/hisilicon/Makefile | 2 +- drivers/crypto/hisilicon/trng/Makefile | 3 + drivers/crypto/hisilicon/trng/trng-stb.c | 176 +++++++++++++++++++++++++++++++ 4 files changed, 187 insertions(+), 1 deletion(-) create mode 100644 drivers/crypto/hisilicon/trng/trng-stb.c (limited to 'drivers/crypto') diff --git a/drivers/crypto/hisilicon/Kconfig b/drivers/crypto/hisilicon/Kconfig index 4137a8bf131f..e8690c223584 100644 --- a/drivers/crypto/hisilicon/Kconfig +++ b/drivers/crypto/hisilicon/Kconfig @@ -82,3 +82,10 @@ config CRYPTO_DEV_HISI_TRNG select CRYPTO_RNG help Support for HiSilicon TRNG Driver. + +config CRYPTO_DEV_HISTB_TRNG + tristate "Support for HiSTB TRNG Driver" + depends on ARCH_HISI || COMPILE_TEST + select HW_RANDOM + help + Support for HiSTB TRNG Driver. diff --git a/drivers/crypto/hisilicon/Makefile b/drivers/crypto/hisilicon/Makefile index 8595a5a5d228..fc51e0edec69 100644 --- a/drivers/crypto/hisilicon/Makefile +++ b/drivers/crypto/hisilicon/Makefile @@ -5,4 +5,4 @@ obj-$(CONFIG_CRYPTO_DEV_HISI_SEC2) += sec2/ obj-$(CONFIG_CRYPTO_DEV_HISI_QM) += hisi_qm.o hisi_qm-objs = qm.o sgl.o debugfs.o obj-$(CONFIG_CRYPTO_DEV_HISI_ZIP) += zip/ -obj-$(CONFIG_CRYPTO_DEV_HISI_TRNG) += trng/ +obj-y += trng/ diff --git a/drivers/crypto/hisilicon/trng/Makefile b/drivers/crypto/hisilicon/trng/Makefile index d909079f351c..cf20b057c66b 100644 --- a/drivers/crypto/hisilicon/trng/Makefile +++ b/drivers/crypto/hisilicon/trng/Makefile @@ -1,2 +1,5 @@ obj-$(CONFIG_CRYPTO_DEV_HISI_TRNG) += hisi-trng-v2.o hisi-trng-v2-objs = trng.o + +obj-$(CONFIG_CRYPTO_DEV_HISTB_TRNG) += histb-trng.o +histb-trng-objs += trng-stb.o diff --git a/drivers/crypto/hisilicon/trng/trng-stb.c b/drivers/crypto/hisilicon/trng/trng-stb.c new file mode 100644 index 000000000000..29200a7d3d81 --- /dev/null +++ b/drivers/crypto/hisilicon/trng/trng-stb.c @@ -0,0 +1,176 @@ +// SPDX-License-Identifier: GPL-2.0-or-later OR MIT +/* + * Device driver for True RNG in HiSTB SoCs + * + * Copyright (c) 2023 David Yang + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define HISTB_TRNG_CTRL 0x0 +#define RNG_SOURCE GENMASK(1, 0) +#define DROP_ENABLE BIT(5) +#define POST_PROCESS_ENABLE BIT(7) +#define POST_PROCESS_DEPTH GENMASK(15, 8) +#define HISTB_TRNG_NUMBER 0x4 +#define HISTB_TRNG_STAT 0x8 +#define DATA_COUNT GENMASK(2, 0) /* max 4 */ + +struct histb_trng_priv { + struct hwrng rng; + void __iomem *base; +}; + +/* + * Observed: + * depth = 1 -> ~1ms + * depth = 255 -> ~16ms + */ +static int histb_trng_wait(void __iomem *base) +{ + u32 val; + + return readl_relaxed_poll_timeout(base + HISTB_TRNG_STAT, val, + val & DATA_COUNT, 1000, 30 * 1000); +} + +static void histb_trng_init(void __iomem *base, unsigned int depth) +{ + u32 val; + + val = readl_relaxed(base + HISTB_TRNG_CTRL); + + val &= ~RNG_SOURCE; + val |= 2; + + val &= ~POST_PROCESS_DEPTH; + val |= min(depth, 0xffu) << 8; + + val |= POST_PROCESS_ENABLE; + val |= DROP_ENABLE; + + writel_relaxed(val, base + HISTB_TRNG_CTRL); +} + +static int histb_trng_read(struct hwrng *rng, void *data, size_t max, bool wait) +{ + struct histb_trng_priv *priv = container_of(rng, typeof(*priv), rng); + void __iomem *base = priv->base; + + for (int i = 0; i < max; i += sizeof(u32)) { + if (!(readl_relaxed(base + HISTB_TRNG_STAT) & DATA_COUNT)) { + if (!wait) + return i; + if (histb_trng_wait(base)) { + pr_err("failed to generate random number, generated %d\n", + i); + return i ? i : -ETIMEDOUT; + } + } + *(u32 *) (data + i) = readl_relaxed(base + HISTB_TRNG_NUMBER); + } + + return max; +} + +static unsigned int histb_trng_get_depth(void __iomem *base) +{ + return (readl_relaxed(base + HISTB_TRNG_CTRL) & POST_PROCESS_DEPTH) >> 8; +} + +static ssize_t +depth_show(struct device *dev, struct device_attribute *attr, char *buf) +{ + struct histb_trng_priv *priv = dev_get_drvdata(dev); + void __iomem *base = priv->base; + + return sprintf(buf, "%d\n", histb_trng_get_depth(base)); +} + +static ssize_t +depth_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct histb_trng_priv *priv = dev_get_drvdata(dev); + void __iomem *base = priv->base; + unsigned int depth; + + if (kstrtouint(buf, 0, &depth)) + return -ERANGE; + + histb_trng_init(base, depth); + return count; +} + +static DEVICE_ATTR_RW(depth); + +static struct attribute *histb_trng_attrs[] = { + &dev_attr_depth.attr, + NULL, +}; + +ATTRIBUTE_GROUPS(histb_trng); + +static int histb_trng_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct histb_trng_priv *priv; + void __iomem *base; + int ret; + + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(base)) + return -ENOMEM; + + histb_trng_init(base, 144); + if (histb_trng_wait(base)) { + dev_err(dev, "cannot bring up device\n"); + return -ENODEV; + } + + priv->base = base; + priv->rng.name = pdev->name; + priv->rng.read = histb_trng_read; + ret = devm_hwrng_register(dev, &priv->rng); + if (ret) { + dev_err(dev, "failed to register hwrng: %d\n", ret); + return ret; + } + + platform_set_drvdata(pdev, priv); + dev_set_drvdata(dev, priv); + return 0; +} + +static const struct of_device_id histb_trng_of_match[] = { + { .compatible = "hisilicon,histb-trng", }, + { } +}; + +static struct platform_driver histb_trng_driver = { + .probe = histb_trng_probe, + .driver = { + .name = "histb-trng", + .of_match_table = histb_trng_of_match, + .dev_groups = histb_trng_groups, + }, +}; + +module_platform_driver(histb_trng_driver); + +MODULE_DESCRIPTION("HiSTB True RNG"); +MODULE_LICENSE("Dual MIT/GPL"); +MODULE_AUTHOR("David Yang "); -- cgit v1.2.3