diff options
| -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/powernv-rng.c | 81 |
3 files changed, 95 insertions, 0 deletions
diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig index 0aa9d91daef5..c206de2951f2 100644 --- a/drivers/char/hw_random/Kconfig +++ b/drivers/char/hw_random/Kconfig @@ -290,6 +290,19 @@ config HW_RANDOM_PSERIES If unsure, say Y. +config HW_RANDOM_POWERNV + tristate "PowerNV Random Number Generator support" + depends on HW_RANDOM && PPC_POWERNV + default HW_RANDOM + ---help--- + This is the driver for Random Number Generator hardware found + in POWER7+ and above machines for PowerNV platform. + + To compile this driver as a module, choose M here: the + module will be called powernv-rng. + + If unsure, say Y. + config HW_RANDOM_EXYNOS tristate "EXYNOS HW random number generator support" depends on HW_RANDOM && HAS_IOMEM && HAVE_CLK diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile index bed467c9300e..d7d2435ff7fa 100644 --- a/drivers/char/hw_random/Makefile +++ b/drivers/char/hw_random/Makefile @@ -24,6 +24,7 @@ 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-$(CONFIG_HW_RANDOM_POWERNV) += powernv-rng.o obj-$(CONFIG_HW_RANDOM_EXYNOS) += exynos-rng.o obj-$(CONFIG_HW_RANDOM_TPM) += tpm-rng.o obj-$(CONFIG_HW_RANDOM_BCM2835) += bcm2835-rng.o diff --git a/drivers/char/hw_random/powernv-rng.c b/drivers/char/hw_random/powernv-rng.c new file mode 100644 index 000000000000..3f4f63204560 --- /dev/null +++ b/drivers/char/hw_random/powernv-rng.c @@ -0,0 +1,81 @@ +/* + * Copyright 2013 Michael Ellerman, Guo Chao, IBM Corp. + * + * 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; either version + * 2 of the License, or (at your option) any later version. + */ + +#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/platform_device.h> +#include <linux/random.h> +#include <linux/hw_random.h> + +static int powernv_rng_read(struct hwrng *rng, void *data, size_t max, bool wait) +{ + unsigned long *buf; + int i, len; + + /* We rely on rng_buffer_size() being >= sizeof(unsigned long) */ + len = max / sizeof(unsigned long); + + buf = (unsigned long *)data; + + for (i = 0; i < len; i++) + powernv_get_random_long(buf++); + + return len * sizeof(unsigned long); +} + +static struct hwrng powernv_hwrng = { + .name = "powernv-rng", + .read = powernv_rng_read, +}; + +static int powernv_rng_remove(struct platform_device *pdev) +{ + hwrng_unregister(&powernv_hwrng); + + return 0; +} + +static int powernv_rng_probe(struct platform_device *pdev) +{ + int rc; + + rc = hwrng_register(&powernv_hwrng); + if (rc) { + /* We only register one device, ignore any others */ + if (rc == -EEXIST) + rc = -ENODEV; + + return rc; + } + + pr_info("Registered powernv hwrng.\n"); + + return 0; +} + +static struct of_device_id powernv_rng_match[] = { + { .compatible = "ibm,power-rng",}, + {}, +}; +MODULE_DEVICE_TABLE(of, powernv_rng_match); + +static struct platform_driver powernv_rng_driver = { + .driver = { + .name = "powernv_rng", + .of_match_table = powernv_rng_match, + }, + .probe = powernv_rng_probe, + .remove = powernv_rng_remove, +}; +module_platform_driver(powernv_rng_driver); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("Bare metal HWRNG driver for POWER7+ and above"); |