pasemi: hardware rng driver (b8cb3448) · Commits · e / devices / android_kernel_teracube_2e

drivers/char/hw_random/Kconfig

+14 −0

Original line number	Original line	Diff line number	Diff line
	@@ -91,3 +91,17 @@ config HW_RANDOM_OMAP
	module will be called omap-rng.		module will be called omap-rng.

	If unsure, say Y.		If unsure, say Y.

			config HW_RANDOM_PASEMI
			tristate "PA Semi HW Random Number Generator support"
			depends on HW_RANDOM && PPC_PASEMI
			default HW_RANDOM
			---help---
			This driver provides kernel-side support for the Random Number
			Generator hardware found on PA6T-1682M processor.

			To compile this driver as a module, choose M here: the
			module will be called pasemi-rng.

			If unsure, say Y.

drivers/char/hw_random/Makefile

+1 −0

Original line number	Original line	Diff line number	Diff line
	@@ -10,3 +10,4 @@ obj-$(CONFIG_HW_RANDOM_GEODE) += geode-rng.o
	obj-$(CONFIG_HW_RANDOM_VIA) += via-rng.o		obj-$(CONFIG_HW_RANDOM_VIA) += via-rng.o
	obj-$(CONFIG_HW_RANDOM_IXP4XX) += ixp4xx-rng.o		obj-$(CONFIG_HW_RANDOM_IXP4XX) += ixp4xx-rng.o
	obj-$(CONFIG_HW_RANDOM_OMAP) += omap-rng.o		obj-$(CONFIG_HW_RANDOM_OMAP) += omap-rng.o
			obj-$(CONFIG_HW_RANDOM_PASEMI) += pasemi-rng.o

drivers/char/hw_random/pasemi-rng.c

0 → 100644

+156 −0

Original line number	Original line	Diff line number	Diff line
			/*
			* Copyright (C) 2006-2007 PA Semi, Inc
			*
			* Maintained by: Olof Johansson <olof@lixom.net>
			*
			* Driver for the PWRficient onchip rng
			*
			* This program is free software; you can redistribute it and/or modify
			* it under the terms of the GNU General Public License version 2 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 <linux/module.h>
			#include <linux/kernel.h>
			#include <linux/platform_device.h>
			#include <linux/hw_random.h>
			#include <asm/of_platform.h>
			#include <asm/io.h>

			#define SDCRNG_CTL_REG 0x00
			#define SDCRNG_CTL_FVLD_M 0x0000f000
			#define SDCRNG_CTL_FVLD_S 12
			#define SDCRNG_CTL_KSZ 0x00000800
			#define SDCRNG_CTL_RSRC_CRG 0x00000010
			#define SDCRNG_CTL_RSRC_RRG 0x00000000
			#define SDCRNG_CTL_CE 0x00000004
			#define SDCRNG_CTL_RE 0x00000002
			#define SDCRNG_CTL_DR 0x00000001
			#define SDCRNG_CTL_SELECT_RRG_RNG (SDCRNG_CTL_RE \| SDCRNG_CTL_RSRC_RRG)
			#define SDCRNG_CTL_SELECT_CRG_RNG (SDCRNG_CTL_CE \| SDCRNG_CTL_RSRC_CRG)
			#define SDCRNG_VAL_REG 0x20

			#define MODULE_NAME "pasemi_rng"

			static int pasemi_rng_data_present(struct hwrng *rng)
			{
			void __iomem rng_regs = (void __iomem )rng->priv;

			return (in_le32(rng_regs + SDCRNG_CTL_REG)
			& SDCRNG_CTL_FVLD_M) ? 1 : 0;
			}

			static int pasemi_rng_data_read(struct hwrng rng, u32 data)
			{
			void __iomem rng_regs = (void __iomem )rng->priv;
			*data = in_le32(rng_regs + SDCRNG_VAL_REG);
			return 4;
			}

			static int pasemi_rng_init(struct hwrng *rng)
			{
			void __iomem rng_regs = (void __iomem )rng->priv;
			u32 ctl;

			ctl = SDCRNG_CTL_DR \| SDCRNG_CTL_SELECT_RRG_RNG \| SDCRNG_CTL_KSZ;
			out_le32(rng_regs + SDCRNG_CTL_REG, ctl);
			out_le32(rng_regs + SDCRNG_CTL_REG, ctl & ~SDCRNG_CTL_DR);

			return 0;
			}

			static void pasemi_rng_cleanup(struct hwrng *rng)
			{
			void __iomem rng_regs = (void __iomem )rng->priv;
			u32 ctl;

			ctl = SDCRNG_CTL_RE \| SDCRNG_CTL_CE;
			out_le32(rng_regs + SDCRNG_CTL_REG,
			in_le32(rng_regs + SDCRNG_CTL_REG) & ~ctl);
			}

			static struct hwrng pasemi_rng = {
			.name = MODULE_NAME,
			.init = pasemi_rng_init,
			.cleanup = pasemi_rng_cleanup,
			.data_present = pasemi_rng_data_present,
			.data_read = pasemi_rng_data_read,
			};

			static int __devinit rng_probe(struct of_device *ofdev,
			const struct of_device_id *match)
			{
			void __iomem *rng_regs;
			struct device_node *rng_np = ofdev->node;
			struct resource res;
			int err = 0;

			err = of_address_to_resource(rng_np, 0, &res);
			if (err)
			return -ENODEV;

			rng_regs = ioremap(res.start, 0x100);

			if (!rng_regs)
			return -ENOMEM;

			pasemi_rng.priv = (unsigned long)rng_regs;

			printk(KERN_INFO "Registering PA Semi RNG\n");

			err = hwrng_register(&pasemi_rng);

			if (err)
			iounmap(rng_regs);

			return err;
			}

			static int __devexit rng_remove(struct of_device *dev)
			{
			void __iomem rng_regs = (void __iomem )pasemi_rng.priv;

			hwrng_unregister(&pasemi_rng);
			iounmap(rng_regs);

			return 0;
			}

			static struct of_device_id rng_match[] = {
			{
			.compatible = "1682m-rng",
			},
			{},
			};

			static struct of_platform_driver rng_driver = {
			.name = "pasemi-rng",
			.match_table = rng_match,
			.probe = rng_probe,
			.remove = rng_remove,
			};

			static int __init rng_init(void)
			{
			return of_register_platform_driver(&rng_driver);
			}
			module_init(rng_init);

			static void __exit rng_exit(void)
			{
			of_unregister_platform_driver(&rng_driver);
			}
			module_exit(rng_exit);

			MODULE_LICENSE("GPL");
			MODULE_AUTHOR("Egor Martovetsky <egor@pasemi.com>");
			MODULE_DESCRIPTION("H/W RNG driver for PA Semi processor");