From ced5e35714f29023bcd0455bb25c281ea84d5bc7 Mon Sep 17 00:00:00 2001 From: Zaibo Xu Date: Thu, 31 Oct 2019 16:34:29 +0800 Subject: [PATCH] hwrng: hisi - add HiSilicon TRNG driver support This series adds HiSilicon true random number generator(TRNG) driver in hw_random subsystem. Signed-off-by: Zaibo Xu Signed-off-by: Weili Qian Signed-off-by: Herbert Xu --- drivers/char/hw_random/Kconfig | 13 ++++ drivers/char/hw_random/Makefile | 1 + drivers/char/hw_random/hisi-trng-v2.c | 99 +++++++++++++++++++++++++++ 3 files changed, 113 insertions(+) create mode 100644 drivers/char/hw_random/hisi-trng-v2.c diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig index 87a1c30e79587..7c7fecfa2fb27 100644 --- a/drivers/char/hw_random/Kconfig +++ b/drivers/char/hw_random/Kconfig @@ -308,6 +308,19 @@ config HW_RANDOM_HISI If unsure, say Y. +config HW_RANDOM_HISI_V2 + tristate "HiSilicon True Random Number Generator V2 support" + depends on HW_RANDOM && ARM64 && ACPI + default HW_RANDOM + help + This driver provides kernel-side support for the True Random Number + Generator V2 hardware found on HiSilicon Hi1620 SoC. + + To compile this driver as a module, choose M here: the + module will be called hisi-trng-v2. + + If unsure, say Y. + config HW_RANDOM_ST tristate "ST Microelectronics HW Random Number Generator support" depends on HW_RANDOM && ARCH_STI diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile index 17b6d4e6d5915..a7801b49ce6c0 100644 --- a/drivers/char/hw_random/Makefile +++ b/drivers/char/hw_random/Makefile @@ -27,6 +27,7 @@ obj-$(CONFIG_HW_RANDOM_NOMADIK) += nomadik-rng.o obj-$(CONFIG_HW_RANDOM_PSERIES) += pseries-rng.o obj-$(CONFIG_HW_RANDOM_POWERNV) += powernv-rng.o obj-$(CONFIG_HW_RANDOM_HISI) += hisi-rng.o +obj-$(CONFIG_HW_RANDOM_HISI_V2) += hisi-trng-v2.o obj-$(CONFIG_HW_RANDOM_BCM2835) += bcm2835-rng.o obj-$(CONFIG_HW_RANDOM_IPROC_RNG200) += iproc-rng200.o obj-$(CONFIG_HW_RANDOM_ST) += st-rng.o diff --git a/drivers/char/hw_random/hisi-trng-v2.c b/drivers/char/hw_random/hisi-trng-v2.c new file mode 100644 index 0000000000000..6a65b8232ce03 --- /dev/null +++ b/drivers/char/hw_random/hisi-trng-v2.c @@ -0,0 +1,99 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright (c) 2019 HiSilicon Limited. */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define HISI_TRNG_REG 0x00F0 +#define HISI_TRNG_BYTES 4 +#define HISI_TRNG_QUALITY 512 +#define SLEEP_US 10 +#define TIMEOUT_US 10000 + +struct hisi_trng { + void __iomem *base; + struct hwrng rng; +}; + +static int hisi_trng_read(struct hwrng *rng, void *buf, size_t max, bool wait) +{ + struct hisi_trng *trng; + int currsize = 0; + u32 val = 0; + u32 ret; + + trng = container_of(rng, struct hisi_trng, rng); + + do { + ret = readl_poll_timeout(trng->base + HISI_TRNG_REG, val, + val, SLEEP_US, TIMEOUT_US); + if (ret) + return currsize; + + if (max - currsize >= HISI_TRNG_BYTES) { + memcpy(buf + currsize, &val, HISI_TRNG_BYTES); + currsize += HISI_TRNG_BYTES; + if (currsize == max) + return currsize; + continue; + } + + /* copy remaining bytes */ + memcpy(buf + currsize, &val, max - currsize); + currsize = max; + } while (currsize < max); + + return currsize; +} + +static int hisi_trng_probe(struct platform_device *pdev) +{ + struct hisi_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)) + return PTR_ERR(trng->base); + + trng->rng.name = pdev->name; + trng->rng.read = hisi_trng_read; + trng->rng.quality = HISI_TRNG_QUALITY; + + ret = devm_hwrng_register(&pdev->dev, &trng->rng); + if (ret) + dev_err(&pdev->dev, "failed to register hwrng!\n"); + + return ret; +} + +static const struct acpi_device_id hisi_trng_acpi_match[] = { + { "HISI02B3", 0 }, + { } +}; +MODULE_DEVICE_TABLE(acpi, hisi_trng_acpi_match); + +static struct platform_driver hisi_trng_driver = { + .probe = hisi_trng_probe, + .driver = { + .name = "hisi-trng-v2", + .acpi_match_table = ACPI_PTR(hisi_trng_acpi_match), + }, +}; + +module_platform_driver(hisi_trng_driver); + +MODULE_LICENSE("GPL v2"); +MODULE_AUTHOR("Weili Qian "); +MODULE_AUTHOR("Zaibo Xu "); +MODULE_DESCRIPTION("HiSilicon true random number generator V2 driver"); -- 2.39.5