diff options
Diffstat (limited to 'drivers/char/hw_random')
| -rw-r--r-- | drivers/char/hw_random/Kconfig | 13 | ||||
| -rw-r--r-- | drivers/char/hw_random/Makefile | 1 | ||||
| -rw-r--r-- | drivers/char/hw_random/pseries-rng.c | 96 |
3 files changed, 110 insertions, 0 deletions
diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig index b2402eb076c..c225314468e 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 b2ff5265a99..d901dfa3032 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 00000000000..5f1197929f0 --- /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 <linux/module.h> +#include <linux/hw_random.h> +#include <asm/vio.h> + +#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 <mikey@neuling.org>"); +MODULE_DESCRIPTION("H/W RNG driver for IBM pSeries processors"); |