This patch adds support for hardware random number generator present in JZ4780 SoC. Signed-off-by: PrasannaKumar Muralidharan <prasannatsmkumar@xxxxxxxxx> --- .../devicetree/bindings/rng/ingenic,jz4780-rng.txt | 12 +++ MAINTAINERS | 5 + arch/mips/boot/dts/ingenic/jz4780.dtsi | 7 +- drivers/char/hw_random/Kconfig | 14 +++ drivers/char/hw_random/Makefile | 1 + drivers/char/hw_random/jz4780-rng.c | 105 +++++++++++++++++++++ 6 files changed, 143 insertions(+), 1 deletion(-) create mode 100644 Documentation/devicetree/bindings/rng/ingenic,jz4780-rng.txt create mode 100644 drivers/char/hw_random/jz4780-rng.c diff --git a/Documentation/devicetree/bindings/rng/ingenic,jz4780-rng.txt b/Documentation/devicetree/bindings/rng/ingenic,jz4780-rng.txt new file mode 100644 index 0000000..03abf56 --- /dev/null +++ b/Documentation/devicetree/bindings/rng/ingenic,jz4780-rng.txt @@ -0,0 +1,12 @@ +Ingenic jz4780 RNG driver + +Required properties: +- compatible : Should be "ingenic,jz4780-rng" +- reg : Specifies base physical address and size of the registers. + +Example: + +rng: rng@100000D8 { + compatible = "ingenic,jz4780-rng"; + reg = <0x100000D8 0x8>; +}; diff --git a/MAINTAINERS b/MAINTAINERS index 08e9efe..c0c66eb 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -6002,6 +6002,11 @@ M: Zubair Lutfullah Kakakhel <Zubair.Kakakhel@xxxxxxxxxx> S: Maintained F: drivers/dma/dma-jz4780.c +INGENIC JZ4780 HW RNG Driver +M: PrasannaKumar Muralidharan <prasannatsmkumar@xxxxxxxxx> +S: Maintained +F: drivers/char/hw_random/jz4780-rng.c + INTEGRITY MEASUREMENT ARCHITECTURE (IMA) M: Mimi Zohar <zohar@xxxxxxxxxxxxxxxxxx> M: Dmitry Kasatkin <dmitry.kasatkin@xxxxxxxxx> diff --git a/arch/mips/boot/dts/ingenic/jz4780.dtsi b/arch/mips/boot/dts/ingenic/jz4780.dtsi index b868b42..f11d139 100644 --- a/arch/mips/boot/dts/ingenic/jz4780.dtsi +++ b/arch/mips/boot/dts/ingenic/jz4780.dtsi @@ -36,7 +36,7 @@ cgu: jz4780-cgu@10000000 { compatible = "ingenic,jz4780-cgu"; - reg = <0x10000000 0x100>; + reg = <0x10000000 0xD8>; clocks = <&ext>, <&rtc>; clock-names = "ext", "rtc"; @@ -44,6 +44,11 @@ #clock-cells = <1>; }; + rng: jz4780-rng@100000D8 { + compatible = "ingenic,jz4780-rng"; + reg = <0x100000D8 0x8>; + }; + uart0: serial@10030000 { compatible = "ingenic,jz4780-uart"; reg = <0x10030000 0x100>; diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig index 56ad5a59..c336fe8 100644 --- a/drivers/char/hw_random/Kconfig +++ b/drivers/char/hw_random/Kconfig @@ -294,6 +294,20 @@ config HW_RANDOM_POWERNV If unsure, say Y. +config HW_RANDOM_JZ4780 + tristate "JZ4780 HW random number generator support" + depends on MACH_INGENIC + depends on HAS_IOMEM + default HW_RANDOM + ---help--- + This driver provides kernel-side support for the Random Number + Generator hardware found on JZ4780 SOCs. + + To compile this driver as a module, choose M here: the + module will be called jz4780-rng. + + If unsure, say Y. + config HW_RANDOM_EXYNOS tristate "EXYNOS HW random number generator support" depends on ARCH_EXYNOS || COMPILE_TEST diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile index 04bb0b0..a155066 100644 --- a/drivers/char/hw_random/Makefile +++ b/drivers/char/hw_random/Makefile @@ -26,6 +26,7 @@ obj-$(CONFIG_HW_RANDOM_PSERIES) += pseries-rng.o obj-$(CONFIG_HW_RANDOM_POWERNV) += powernv-rng.o obj-$(CONFIG_HW_RANDOM_EXYNOS) += exynos-rng.o obj-$(CONFIG_HW_RANDOM_HISI) += hisi-rng.o +obj-$(CONFIG_HW_RANDOM_JZ4780) += jz4780-rng.o obj-$(CONFIG_HW_RANDOM_TPM) += tpm-rng.o obj-$(CONFIG_HW_RANDOM_BCM2835) += bcm2835-rng.o obj-$(CONFIG_HW_RANDOM_IPROC_RNG200) += iproc-rng200.o diff --git a/drivers/char/hw_random/jz4780-rng.c b/drivers/char/hw_random/jz4780-rng.c new file mode 100644 index 0000000..c9d2cde --- /dev/null +++ b/drivers/char/hw_random/jz4780-rng.c @@ -0,0 +1,105 @@ +/* + * jz4780-rng.c - Random Number Generator driver for J4780 + * + * Copyright 2016 (C) PrasannaKumar Muralidharan <prasannatsmkumar@xxxxxxxxx> + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include <linux/hw_random.h> +#include <linux/device.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/io.h> +#include <linux/platform_device.h> +#include <linux/err.h> + +#define REG_RNG_CTRL 0x0 +#define REG_RNG_DATA 0x4 + +struct jz4780_rng { + struct device *dev; + struct hwrng rng; + void __iomem *mem; +}; + +static u32 jz4780_rng_readl(struct jz4780_rng *rng, u32 offset) +{ + return readl(rng->mem + offset); +} + +static void jz4780_rng_writel(struct jz4780_rng *rng, u32 val, u32 offset) +{ + writel(val, rng->mem + offset); +} + +static int jz4780_rng_read(struct hwrng *rng, void *buf, size_t max, bool wait) +{ + struct jz4780_rng *jz4780_rng = container_of(rng, struct jz4780_rng, + rng); + u32 *data = buf; + *data = jz4780_rng_readl(jz4780_rng, REG_RNG_DATA); + return 4; +} + +static int jz4780_rng_probe(struct platform_device *pdev) +{ + struct jz4780_rng *jz4780_rng; + struct resource *res; + resource_size_t size; + int ret; + + jz4780_rng = devm_kzalloc(&pdev->dev, sizeof(struct jz4780_rng), + GFP_KERNEL); + if (!jz4780_rng) + return -ENOMEM; + + jz4780_rng->dev = &pdev->dev; + jz4780_rng->rng.name = "jz4780"; + jz4780_rng->rng.read = jz4780_rng_read; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + size = resource_size(res); + + jz4780_rng->mem = devm_ioremap(&pdev->dev, res->start, size); + if (IS_ERR(jz4780_rng->mem)) + return PTR_ERR(jz4780_rng->mem); + + platform_set_drvdata(pdev, jz4780_rng); + jz4780_rng_writel(jz4780_rng, 1, REG_RNG_CTRL); + ret = hwrng_register(&jz4780_rng->rng); + + return ret; +} + +static int jz4780_rng_remove(struct platform_device *pdev) +{ + struct jz4780_rng *jz4780_rng = platform_get_drvdata(pdev); + + jz4780_rng_writel(jz4780_rng, 0, REG_RNG_CTRL); + hwrng_unregister(&jz4780_rng->rng); + + return 0; +} + +static const struct of_device_id jz4780_rng_dt_match[] = { + { .compatible = "ingenic,jz4780-rng", }, + { }, +}; +MODULE_DEVICE_TABLE(of, jz4780_rng_dt_match); + +static struct platform_driver jz4780_rng_driver = { + .driver = { + .name = "jz4780-rng", + .of_match_table = jz4780_rng_dt_match, + }, + .probe = jz4780_rng_probe, + .remove = jz4780_rng_remove, +}; +module_platform_driver(jz4780_rng_driver); + +MODULE_DESCRIPTION("Ingenic JZ4780 H/W Random Number Generator driver"); +MODULE_AUTHOR("PrasannaKumar Muralidharan <prasannatsmkumar@xxxxxxxxx>"); +MODULE_LICENSE("GPL"); -- 2.5.0