From 3621189064301a5fbb5d06ca17d966a026f4e501 Mon Sep 17 00:00:00 2001 From: Benoît Thébaudeau Date: Wed, 13 Jun 2012 18:15:34 +0200 Subject: hwrng: mxc-rnga - fix data_present API MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Commit 45001e9, which added support for RNGA, ignored the previous commit 984e976, which changed the data_present API. Cc: Matt Mackall Cc: Sascha Hauer Cc: Alan Carvalho de Assis Cc: Signed-off-by: Benoît Thébaudeau Signed-off-by: Herbert Xu --- drivers/char/hw_random/mxc-rnga.c | 21 +++++++++++++-------- 1 file changed, 13 insertions(+), 8 deletions(-) (limited to 'drivers/char') diff --git a/drivers/char/hw_random/mxc-rnga.c b/drivers/char/hw_random/mxc-rnga.c index 187c6be80f43..85074de5042e 100644 --- a/drivers/char/hw_random/mxc-rnga.c +++ b/drivers/char/hw_random/mxc-rnga.c @@ -24,6 +24,7 @@ #include #include #include +#include #include /* RNGA Registers */ @@ -60,16 +61,20 @@ static struct platform_device *rng_dev; -static int mxc_rnga_data_present(struct hwrng *rng) +static int mxc_rnga_data_present(struct hwrng *rng, int wait) { - int level; void __iomem *rng_base = (void __iomem *)rng->priv; - - /* how many random numbers is in FIFO? [0-16] */ - level = ((__raw_readl(rng_base + RNGA_STATUS) & - RNGA_STATUS_LEVEL_MASK) >> 8); - - return level > 0 ? 1 : 0; + int i; + + for (i = 0; i < 20; i++) { + /* how many random numbers are in FIFO? [0-16] */ + int level = (__raw_readl(rng_base + RNGA_STATUS) & + RNGA_STATUS_LEVEL_MASK) >> 8; + if (level || !wait) + return !!level; + udelay(10); + } + return 0; } static int mxc_rnga_data_read(struct hwrng *rng, u32 * data) -- cgit v1.2.3 From b329669ea0b5b02efd41f94372bcf0e988814af4 Mon Sep 17 00:00:00 2001 From: Jonghwa Lee Date: Fri, 29 Jun 2012 09:43:26 +0900 Subject: hwrng: exynos - Add support for Exynos random number generator This patch supports Exynos SOC's PRNG driver. Exynos's PRNG has 5 seeds and 5 random number outputs. Module is excuted under runtime power management control, so it activates only while it's in use. Otherwise it will be suspended generally. It was tested on PQ board by rngtest program. Signed-off-by: Jonghwa Lee Signed-off-by: Kyungmin Park Reviewed-by: Stephen Boyd Signed-off-by: Herbert Xu --- drivers/char/hw_random/Kconfig | 12 +++ drivers/char/hw_random/Makefile | 1 + drivers/char/hw_random/exynos-rng.c | 182 ++++++++++++++++++++++++++++++++++++ 3 files changed, 195 insertions(+) create mode 100644 drivers/char/hw_random/exynos-rng.c (limited to 'drivers/char') diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig index f45dad39a18b..b01d67328243 100644 --- a/drivers/char/hw_random/Kconfig +++ b/drivers/char/hw_random/Kconfig @@ -263,3 +263,15 @@ config HW_RANDOM_PSERIES module will be called pseries-rng. If unsure, say Y. + +config HW_RANDOM_EXYNOS + tristate "EXYNOS HW random number generator support" + depends on HW_RANDOM && HAS_IOMEM && HAVE_CLK + ---help--- + This driver provides kernel-side support for the Random Number + Generator hardware found on EXYNOS SOCs. + + To compile this driver as a module, choose M here: the + module will be called exynos-rng. + + If unsure, say Y. diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile index d901dfa30321..8d6d173b65e6 100644 --- a/drivers/char/hw_random/Makefile +++ b/drivers/char/hw_random/Makefile @@ -23,3 +23,4 @@ obj-$(CONFIG_HW_RANDOM_NOMADIK) += nomadik-rng.o obj-$(CONFIG_HW_RANDOM_PICOXCELL) += picoxcell-rng.o obj-$(CONFIG_HW_RANDOM_PPC4XX) += ppc4xx-rng.o obj-$(CONFIG_HW_RANDOM_PSERIES) += pseries-rng.o +obj-$(CONFIG_HW_RANDOM_EXYNOS) += exynos-rng.o diff --git a/drivers/char/hw_random/exynos-rng.c b/drivers/char/hw_random/exynos-rng.c new file mode 100644 index 000000000000..232ba9ce579c --- /dev/null +++ b/drivers/char/hw_random/exynos-rng.c @@ -0,0 +1,182 @@ +/* + * exynos-rng.c - Random Number Generator driver for the exynos + * + * Copyright (C) 2012 Samsung Electronics + * Jonghwa Lee + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA + * + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define EXYNOS_PRNG_STATUS_OFFSET 0x10 +#define EXYNOS_PRNG_SEED_OFFSET 0x140 +#define EXYNOS_PRNG_OUT1_OFFSET 0x160 +#define SEED_SETTING_DONE BIT(1) +#define PRNG_START 0x18 +#define PRNG_DONE BIT(5) +#define EXYNOS_AUTOSUSPEND_DELAY 100 + +struct exynos_rng { + struct device *dev; + struct hwrng rng; + void __iomem *mem; + struct clk *clk; +}; + +static u32 exynos_rng_readl(struct exynos_rng *rng, u32 offset) +{ + return __raw_readl(rng->mem + offset); +} + +static void exynos_rng_writel(struct exynos_rng *rng, u32 val, u32 offset) +{ + __raw_writel(val, rng->mem + offset); +} + +static int exynos_init(struct hwrng *rng) +{ + struct exynos_rng *exynos_rng = container_of(rng, + struct exynos_rng, rng); + int i; + int ret = 0; + + pm_runtime_get_sync(exynos_rng->dev); + + for (i = 0 ; i < 5 ; i++) + exynos_rng_writel(exynos_rng, jiffies, + EXYNOS_PRNG_SEED_OFFSET + 4*i); + + if (!(exynos_rng_readl(exynos_rng, EXYNOS_PRNG_STATUS_OFFSET) + & SEED_SETTING_DONE)) + ret = -EIO; + + pm_runtime_put_noidle(exynos_rng->dev); + + return ret; +} + +static int exynos_read(struct hwrng *rng, void *buf, + size_t max, bool wait) +{ + struct exynos_rng *exynos_rng = container_of(rng, + struct exynos_rng, rng); + u32 *data = buf; + + pm_runtime_get_sync(exynos_rng->dev); + + exynos_rng_writel(exynos_rng, PRNG_START, 0); + + while (!(exynos_rng_readl(exynos_rng, + EXYNOS_PRNG_STATUS_OFFSET) & PRNG_DONE)) + cpu_relax(); + + exynos_rng_writel(exynos_rng, PRNG_DONE, EXYNOS_PRNG_STATUS_OFFSET); + + *data = exynos_rng_readl(exynos_rng, EXYNOS_PRNG_OUT1_OFFSET); + + pm_runtime_mark_last_busy(exynos_rng->dev); + pm_runtime_autosuspend(exynos_rng->dev); + + return 4; +} + +static int __devinit exynos_rng_probe(struct platform_device *pdev) +{ + struct exynos_rng *exynos_rng; + + exynos_rng = devm_kzalloc(&pdev->dev, sizeof(struct exynos_rng), + GFP_KERNEL); + if (!exynos_rng) + return -ENOMEM; + + exynos_rng->dev = &pdev->dev; + exynos_rng->rng.name = "exynos"; + exynos_rng->rng.init = exynos_init; + exynos_rng->rng.read = exynos_read; + exynos_rng->clk = devm_clk_get(&pdev->dev, "secss"); + if (IS_ERR(exynos_rng->clk)) { + dev_err(&pdev->dev, "Couldn't get clock.\n"); + return -ENOENT; + } + + exynos_rng->mem = devm_request_and_ioremap(&pdev->dev, + platform_get_resource(pdev, IORESOURCE_MEM, 0)); + if (!exynos_rng->mem) + return -EBUSY; + + platform_set_drvdata(pdev, exynos_rng); + + pm_runtime_set_autosuspend_delay(&pdev->dev, EXYNOS_AUTOSUSPEND_DELAY); + pm_runtime_use_autosuspend(&pdev->dev); + pm_runtime_enable(&pdev->dev); + + return hwrng_register(&exynos_rng->rng); +} + +static int __devexit exynos_rng_remove(struct platform_device *pdev) +{ + struct exynos_rng *exynos_rng = platform_get_drvdata(pdev); + + hwrng_unregister(&exynos_rng->rng); + + return 0; +} + +static int exynos_rng_runtime_suspend(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct exynos_rng *exynos_rng = platform_get_drvdata(pdev); + + clk_disable_unprepare(exynos_rng->clk); + + return 0; +} + +static int exynos_rng_runtime_resume(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct exynos_rng *exynos_rng = platform_get_drvdata(pdev); + + return clk_prepare_enable(exynos_rng->clk); +} + + +UNIVERSAL_DEV_PM_OPS(exynos_rng_pm_ops, exynos_rng_runtime_suspend, + exynos_rng_runtime_resume, NULL); + +static struct platform_driver exynos_rng_driver = { + .driver = { + .name = "exynos-rng", + .owner = THIS_MODULE, + .pm = &exynos_rng_pm_ops, + }, + .probe = exynos_rng_probe, + .remove = __devexit_p(exynos_rng_remove), +}; + +module_platform_driver(exynos_rng_driver); + +MODULE_DESCRIPTION("EXYNOS 4 H/W Random Number Generator driver"); +MODULE_AUTHOR("Jonghwa Lee "); +MODULE_LICENSE("GPL"); -- cgit v1.2.3