From: 周琰杰 (Zhou Yanjie) Date: Sun, 13 Sep 2020 16:10:21 +0000 (+0800) Subject: hwrng: ingenic - Add hardware TRNG for Ingenic X1830 X-Git-Tag: v5.10.7~1291^2~91 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=406346d2227854bd9a5abdf07ef3d45d0de85a3e;p=platform%2Fkernel%2Flinux-rpi.git hwrng: ingenic - Add hardware TRNG for Ingenic X1830 Add X1830 SoC digital true random number generator driver. Tested-by: 周正 (Zhou Zheng) Co-developed-by: 漆鹏振 (Qi Pengzhen) Signed-off-by: 漆鹏振 (Qi Pengzhen) Signed-off-by: 周琰杰 (Zhou Yanjie) Signed-off-by: Herbert Xu --- diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig index 007d765..e92c4d9 100644 --- a/drivers/char/hw_random/Kconfig +++ b/drivers/char/hw_random/Kconfig @@ -282,6 +282,20 @@ config HW_RANDOM_INGENIC_RNG If unsure, say Y. +config HW_RANDOM_INGENIC_TRNG + tristate "Ingenic True Random Number Generator support" + depends on HW_RANDOM + depends on MACH_X1830 + default HW_RANDOM + help + This driver provides kernel-side support for the True Random Number Generator + hardware found in ingenic X1830 SoC. YSH & ATIL CU1830-Neo uses X1830 SoC. + + To compile this driver as a module, choose M here: the + module will be called ingenic-trng. + + If unsure, say Y. + config HW_RANDOM_NOMADIK tristate "ST-Ericsson Nomadik Random Number Generator support" depends on ARCH_NOMADIK diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile index dfdcac8..5da3445 100644 --- a/drivers/char/hw_random/Makefile +++ b/drivers/char/hw_random/Makefile @@ -24,6 +24,7 @@ obj-$(CONFIG_HW_RANDOM_TX4939) += tx4939-rng.o obj-$(CONFIG_HW_RANDOM_MXC_RNGA) += mxc-rnga.o obj-$(CONFIG_HW_RANDOM_IMX_RNGC) += imx-rngc.o obj-$(CONFIG_HW_RANDOM_INGENIC_RNG) += ingenic-rng.o +obj-$(CONFIG_HW_RANDOM_INGENIC_TRNG) += ingenic-trng.o obj-$(CONFIG_HW_RANDOM_OCTEON) += octeon-rng.o obj-$(CONFIG_HW_RANDOM_NOMADIK) += nomadik-rng.o obj-$(CONFIG_HW_RANDOM_PSERIES) += pseries-rng.o diff --git a/drivers/char/hw_random/ingenic-trng.c b/drivers/char/hw_random/ingenic-trng.c new file mode 100644 index 0000000..954a841 --- /dev/null +++ b/drivers/char/hw_random/ingenic-trng.c @@ -0,0 +1,161 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Ingenic True Random Number Generator driver + * Copyright (c) 2019 漆鹏振 (Qi Pengzhen) + * Copyright (c) 2020 周琰杰 (Zhou Yanjie) + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +/* DTRNG register offsets */ +#define TRNG_REG_CFG_OFFSET 0x00 +#define TRNG_REG_RANDOMNUM_OFFSET 0x04 +#define TRNG_REG_STATUS_OFFSET 0x08 + +/* bits within the CFG register */ +#define CFG_RDY_CLR BIT(12) +#define CFG_INT_MASK BIT(11) +#define CFG_GEN_EN BIT(0) + +/* bits within the STATUS register */ +#define STATUS_RANDOM_RDY BIT(0) + +struct ingenic_trng { + void __iomem *base; + struct clk *clk; + struct hwrng rng; +}; + +static int ingenic_trng_init(struct hwrng *rng) +{ + struct ingenic_trng *trng = container_of(rng, struct ingenic_trng, rng); + unsigned int ctrl; + + ctrl = readl(trng->base + TRNG_REG_CFG_OFFSET); + ctrl |= CFG_GEN_EN; + writel(ctrl, trng->base + TRNG_REG_CFG_OFFSET); + + return 0; +} + +static void ingenic_trng_cleanup(struct hwrng *rng) +{ + struct ingenic_trng *trng = container_of(rng, struct ingenic_trng, rng); + unsigned int ctrl; + + ctrl = readl(trng->base + TRNG_REG_CFG_OFFSET); + ctrl &= ~CFG_GEN_EN; + writel(ctrl, trng->base + TRNG_REG_CFG_OFFSET); +} + +static int ingenic_trng_read(struct hwrng *rng, void *buf, size_t max, bool wait) +{ + struct ingenic_trng *trng = container_of(rng, struct ingenic_trng, rng); + u32 *data = buf; + u32 status; + int ret; + + ret = readl_poll_timeout(trng->base + TRNG_REG_STATUS_OFFSET, status, + status & STATUS_RANDOM_RDY, 10, 1000); + if (ret == -ETIMEDOUT) { + pr_err("%s: Wait for DTRNG data ready timeout\n", __func__); + return ret; + } + + *data = readl(trng->base + TRNG_REG_RANDOMNUM_OFFSET); + + return 4; +} + +static int ingenic_trng_probe(struct platform_device *pdev) +{ + struct ingenic_trng *trng; + int ret; + + trng = devm_kzalloc(&pdev->dev, sizeof(*trng), GFP_KERNEL); + if (!trng) + return -ENOMEM; + + trng->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(trng->base)) { + pr_err("%s: Failed to map DTRNG registers\n", __func__); + ret = PTR_ERR(trng->base); + return PTR_ERR(trng->base); + } + + trng->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(trng->clk)) { + ret = PTR_ERR(trng->clk); + pr_crit("%s: Cannot get DTRNG clock\n", __func__); + return PTR_ERR(trng->clk); + } + + ret = clk_prepare_enable(trng->clk); + if (ret) { + pr_crit("%s: Unable to enable DTRNG clock\n", __func__); + return ret; + } + + trng->rng.name = pdev->name; + trng->rng.init = ingenic_trng_init; + trng->rng.cleanup = ingenic_trng_cleanup; + trng->rng.read = ingenic_trng_read; + + ret = hwrng_register(&trng->rng); + if (ret) { + dev_err(&pdev->dev, "Failed to register hwrng\n"); + return ret; + } + + platform_set_drvdata(pdev, trng); + + dev_info(&pdev->dev, "Ingenic DTRNG driver registered\n"); + return 0; +} + +static int ingenic_trng_remove(struct platform_device *pdev) +{ + struct ingenic_trng *trng = platform_get_drvdata(pdev); + unsigned int ctrl; + + hwrng_unregister(&trng->rng); + + ctrl = readl(trng->base + TRNG_REG_CFG_OFFSET); + ctrl &= ~CFG_GEN_EN; + writel(ctrl, trng->base + TRNG_REG_CFG_OFFSET); + + clk_disable_unprepare(trng->clk); + + return 0; +} + +static const struct of_device_id ingenic_trng_of_match[] = { + { .compatible = "ingenic,x1830-dtrng" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, ingenic_trng_of_match); + +static struct platform_driver ingenic_trng_driver = { + .probe = ingenic_trng_probe, + .remove = ingenic_trng_remove, + .driver = { + .name = "ingenic-trng", + .of_match_table = ingenic_trng_of_match, + }, +}; + +module_platform_driver(ingenic_trng_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("漆鹏振 (Qi Pengzhen) "); +MODULE_AUTHOR("周琰杰 (Zhou Yanjie) "); +MODULE_DESCRIPTION("Ingenic True Random Number Generator driver");