From: Kent Yoder Subject: [PATCH v2 04/17] hwrng: pseries - PFO-based hwrng driver Date: Tue, 10 Apr 2012 10:08:50 -0500 Message-ID: <1334070530.16827.9.camel@key-ThinkPad-W510> References: <1334070249.16827.1.camel@key-ThinkPad-W510> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: linux-crypto@vger.kernel.org, rcj@linux.vnet.ibm.com, key@linux.vnet.ibm.com, benh@kernel.crashing.org, linuxppc-dev@lists.ozlabs.org To: linux-kernel@vger.kernel.org Return-path: Received: from e38.co.us.ibm.com ([32.97.110.159]:60692 "EHLO e38.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1759061Ab2DJPJd (ORCPT ); Tue, 10 Apr 2012 11:09:33 -0400 Received: from /spool/local by e38.co.us.ibm.com with IBM ESMTP SMTP Gateway: Authorized Use Only! Violators will be prosecuted for from ; Tue, 10 Apr 2012 09:09:32 -0600 In-Reply-To: <1334070249.16827.1.camel@key-ThinkPad-W510> Sender: linux-crypto-owner@vger.kernel.org List-ID: Adds support for the Platform Facilities Option (PFO)-based hardware random number generator for POWER hardware. Signed-off-by: Michael Neuling Signed-off-by: Robert Jennings Signed-off-by: Kent Yoder --- drivers/char/hw_random/Kconfig | 13 +++++ drivers/char/hw_random/Makefile | 1 + drivers/char/hw_random/pseries-rng.c | 96 ++++++++++++++++++++++++++++++++++ 3 files changed, 110 insertions(+), 0 deletions(-) create mode 100644 drivers/char/hw_random/pseries-rng.c diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig index 0689bf6..9355347 100644 --- a/drivers/char/hw_random/Kconfig +++ b/drivers/char/hw_random/Kconfig @@ -250,3 +250,16 @@ config UML_RANDOM (check your distro, or download from http://sourceforge.net/projects/gkernel/). rngd periodically reads /dev/hwrng and injects the entropy into /dev/random. + +config HW_RANDOM_PSERIES + tristate "pSeries HW Random Number Generator support" + depends on HW_RANDOM && PPC64 && IBMVIO + default HW_RANDOM + ---help--- + This driver provides kernel-side support for the Random Number + Generator hardware found on POWER7+ machines and above + + To compile this driver as a module, choose M here: the + module will be called pseries-rng. + + If unsure, say Y. diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile index b2ff526..d901dfa 100644 --- a/drivers/char/hw_random/Makefile +++ b/drivers/char/hw_random/Makefile @@ -22,3 +22,4 @@ obj-$(CONFIG_HW_RANDOM_OCTEON) += octeon-rng.o obj-$(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 diff --git a/drivers/char/hw_random/pseries-rng.c b/drivers/char/hw_random/pseries-rng.c new file mode 100644 index 0000000..5f11979 --- /dev/null +++ b/drivers/char/hw_random/pseries-rng.c @@ -0,0 +1,96 @@ +/* + * Copyright (C) 2010 Michael Neuling IBM Corporation + * + * Driver for the pseries hardware RNG for POWER7+ and above + * + * 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 +#include +#include + +#define MODULE_NAME "pseries-rng" + +static int pseries_rng_data_read(struct hwrng *rng, u32 *data) +{ + if (plpar_hcall(H_RANDOM, (unsigned long *)data) != H_SUCCESS) { + printk(KERN_ERR "pseries rng hcall error\n"); + return 0; + } + return 8; +} + +/** + * pseries_rng_get_desired_dma - Return desired DMA allocate for CMO operations + * + * This is a required function for a driver to operate in a CMO environment + * but this device does not make use of DMA allocations, return 0. + * + * Return value: + * Number of bytes of IO data the driver will need to perform well -> 0 + */ +static unsigned long pseries_rng_get_desired_dma(struct vio_dev *vdev) +{ + return 0; +}; + +static struct hwrng pseries_rng = { + .name = MODULE_NAME, + .data_read = pseries_rng_data_read, +}; + +static int __init pseries_rng_probe(struct vio_dev *dev, + const struct vio_device_id *id) +{ + return hwrng_register(&pseries_rng); +} + +static int __exit pseries_rng_remove(struct vio_dev *dev) +{ + hwrng_unregister(&pseries_rng); + return 0; +} + +static struct vio_device_id pseries_rng_driver_ids[] = { + { "ibm,random-v1", "ibm,random"}, + { "", "" } +}; +MODULE_DEVICE_TABLE(vio, pseries_rng_driver_ids); + +static struct vio_driver pseries_rng_driver = { + .name = MODULE_NAME, + .probe = pseries_rng_probe, + .remove = pseries_rng_remove, + .get_desired_dma = pseries_rng_get_desired_dma, + .id_table = pseries_rng_driver_ids +}; + +static int __init rng_init(void) +{ + printk(KERN_INFO "Registering IBM pSeries RNG driver\n"); + return vio_register_driver(&pseries_rng_driver); +} + +module_init(rng_init); + +static void __exit rng_exit(void) +{ + vio_unregister_driver(&pseries_rng_driver); +} +module_exit(rng_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Michael Neuling "); +MODULE_DESCRIPTION("H/W RNG driver for IBM pSeries processors"); -- 1.7.1