diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-16 09:15:21 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-03-16 09:15:21 -0700 |
commit | 0d2ecee2bdb2a19d04bc5cefac0f86e790f1aad4 (patch) | |
tree | 2e0f08819a57e2c191f6e7fe2b2cd2f2415143bd /drivers/char | |
parent | 3ae2a1ce2e7b70254e5c9e465adefac9cba191d6 (diff) | |
parent | f07ef1de9baeb2add514c51f59d4bc3c659c2ca4 (diff) |
Merge git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
crypto: tcrypt - do not attempt to write to readonly variable
random: update interface comments to reflect reality
crypto: picoxcell - add support for the picoxcell crypto engines
crypto: sha1 - Add test vector to test partial block processing
hwrng: omap - Convert release_resource to release_region/release_mem_region
crypto: aesni-intel - Fix remaining leak in rfc4106_set_hash_key
crypto: omap-sham - don't treat NULL clk as an error
crypto: omap-aes - don't treat NULL clk as an error
crypto: testmgr - mark ghash as fips_allowed
crypto: testmgr - mark xts(aes) as fips_allowed
crypto: skcipher - remove redundant NULL check
hwrng: pixocell - add support for picoxcell TRNG
crypto: aesni-intel - Don't leak memory in rfc4106_set_hash_subkey
Diffstat (limited to 'drivers/char')
-rw-r--r-- | drivers/char/hw_random/Kconfig | 12 | ||||
-rw-r--r-- | drivers/char/hw_random/Makefile | 1 | ||||
-rw-r--r-- | drivers/char/hw_random/omap-rng.c | 14 | ||||
-rw-r--r-- | drivers/char/hw_random/picoxcell-rng.c | 208 | ||||
-rw-r--r-- | drivers/char/random.c | 13 |
5 files changed, 237 insertions, 11 deletions
diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig index d31483c5488..beecd1cf9b9 100644 --- a/drivers/char/hw_random/Kconfig +++ b/drivers/char/hw_random/Kconfig @@ -198,3 +198,15 @@ config HW_RANDOM_NOMADIK module will be called nomadik-rng. If unsure, say Y. + +config HW_RANDOM_PICOXCELL + tristate "Picochip picoXcell true random number generator support" + depends on HW_RANDOM && ARCH_PICOXCELL && PICOXCELL_PC3X3 + ---help--- + This driver provides kernel-side support for the Random Number + Generator hardware found on Picochip PC3x3 and later devices. + + To compile this driver as a module, choose M here: the + module will be called picoxcell-rng. + + If unsure, say Y. diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile index 4273308aa1e..3db4eb8b19c 100644 --- a/drivers/char/hw_random/Makefile +++ b/drivers/char/hw_random/Makefile @@ -19,3 +19,4 @@ obj-$(CONFIG_HW_RANDOM_TX4939) += tx4939-rng.o obj-$(CONFIG_HW_RANDOM_MXC_RNGA) += mxc-rnga.o obj-$(CONFIG_HW_RANDOM_OCTEON) += octeon-rng.o obj-$(CONFIG_HW_RANDOM_NOMADIK) += nomadik-rng.o +obj-$(CONFIG_HW_RANDOM_PICOXCELL) += picoxcell-rng.o diff --git a/drivers/char/hw_random/omap-rng.c b/drivers/char/hw_random/omap-rng.c index 06aad0831c7..2cc755a6430 100644 --- a/drivers/char/hw_random/omap-rng.c +++ b/drivers/char/hw_random/omap-rng.c @@ -91,7 +91,7 @@ static struct hwrng omap_rng_ops = { static int __devinit omap_rng_probe(struct platform_device *pdev) { - struct resource *res, *mem; + struct resource *res; int ret; /* @@ -116,14 +116,12 @@ static int __devinit omap_rng_probe(struct platform_device *pdev) if (!res) return -ENOENT; - mem = request_mem_region(res->start, resource_size(res), - pdev->name); - if (mem == NULL) { + if (!request_mem_region(res->start, resource_size(res), pdev->name)) { ret = -EBUSY; goto err_region; } - dev_set_drvdata(&pdev->dev, mem); + dev_set_drvdata(&pdev->dev, res); rng_base = ioremap(res->start, resource_size(res)); if (!rng_base) { ret = -ENOMEM; @@ -146,7 +144,7 @@ err_register: iounmap(rng_base); rng_base = NULL; err_ioremap: - release_resource(mem); + release_mem_region(res->start, resource_size(res)); err_region: if (cpu_is_omap24xx()) { clk_disable(rng_ick); @@ -157,7 +155,7 @@ err_region: static int __exit omap_rng_remove(struct platform_device *pdev) { - struct resource *mem = dev_get_drvdata(&pdev->dev); + struct resource *res = dev_get_drvdata(&pdev->dev); hwrng_unregister(&omap_rng_ops); @@ -170,7 +168,7 @@ static int __exit omap_rng_remove(struct platform_device *pdev) clk_put(rng_ick); } - release_resource(mem); + release_mem_region(res->start, resource_size(res)); rng_base = NULL; return 0; diff --git a/drivers/char/hw_random/picoxcell-rng.c b/drivers/char/hw_random/picoxcell-rng.c new file mode 100644 index 00000000000..990d55a5e3e --- /dev/null +++ b/drivers/char/hw_random/picoxcell-rng.c @@ -0,0 +1,208 @@ +/* + * Copyright (c) 2010-2011 Picochip Ltd., Jamie Iles + * + * 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. + * + * All enquiries to support@picochip.com + */ +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/err.h> +#include <linux/hw_random.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/platform_device.h> + +#define DATA_REG_OFFSET 0x0200 +#define CSR_REG_OFFSET 0x0278 +#define CSR_OUT_EMPTY_MASK (1 << 24) +#define CSR_FAULT_MASK (1 << 1) +#define TRNG_BLOCK_RESET_MASK (1 << 0) +#define TAI_REG_OFFSET 0x0380 + +/* + * The maximum amount of time in microseconds to spend waiting for data if the + * core wants us to wait. The TRNG should generate 32 bits every 320ns so a + * timeout of 20us seems reasonable. The TRNG does builtin tests of the data + * for randomness so we can't always assume there is data present. + */ +#define PICO_TRNG_TIMEOUT 20 + +static void __iomem *rng_base; +static struct clk *rng_clk; +struct device *rng_dev; + +static inline u32 picoxcell_trng_read_csr(void) +{ + return __raw_readl(rng_base + CSR_REG_OFFSET); +} + +static inline bool picoxcell_trng_is_empty(void) +{ + return picoxcell_trng_read_csr() & CSR_OUT_EMPTY_MASK; +} + +/* + * Take the random number generator out of reset and make sure the interrupts + * are masked. We shouldn't need to get large amounts of random bytes so just + * poll the status register. The hardware generates 32 bits every 320ns so we + * shouldn't have to wait long enough to warrant waiting for an IRQ. + */ +static void picoxcell_trng_start(void) +{ + __raw_writel(0, rng_base + TAI_REG_OFFSET); + __raw_writel(0, rng_base + CSR_REG_OFFSET); +} + +static void picoxcell_trng_reset(void) +{ + __raw_writel(TRNG_BLOCK_RESET_MASK, rng_base + CSR_REG_OFFSET); + __raw_writel(TRNG_BLOCK_RESET_MASK, rng_base + TAI_REG_OFFSET); + picoxcell_trng_start(); +} + +/* + * Get some random data from the random number generator. The hw_random core + * layer provides us with locking. + */ +static int picoxcell_trng_read(struct hwrng *rng, void *buf, size_t max, + bool wait) +{ + int i; + + /* Wait for some data to become available. */ + for (i = 0; i < PICO_TRNG_TIMEOUT && picoxcell_trng_is_empty(); ++i) { + if (!wait) + return 0; + + udelay(1); + } + + if (picoxcell_trng_read_csr() & CSR_FAULT_MASK) { + dev_err(rng_dev, "fault detected, resetting TRNG\n"); + picoxcell_trng_reset(); + return -EIO; + } + + if (i == PICO_TRNG_TIMEOUT) + return 0; + + *(u32 *)buf = __raw_readl(rng_base + DATA_REG_OFFSET); + return sizeof(u32); +} + +static struct hwrng picoxcell_trng = { + .name = "picoxcell", + .read = picoxcell_trng_read, +}; + +static int picoxcell_trng_probe(struct platform_device *pdev) +{ + int ret; + struct resource *mem = platform_get_resource(pdev, IORESOURCE_MEM, 0); + + if (!mem) { + dev_warn(&pdev->dev, "no memory resource\n"); + return -ENOMEM; + } + + if (!devm_request_mem_region(&pdev->dev, mem->start, resource_size(mem), + "picoxcell_trng")) { + dev_warn(&pdev->dev, "unable to request io mem\n"); + return -EBUSY; + } + + rng_base = devm_ioremap(&pdev->dev, mem->start, resource_size(mem)); + if (!rng_base) { + dev_warn(&pdev->dev, "unable to remap io mem\n"); + return -ENOMEM; + } + + rng_clk = clk_get(&pdev->dev, NULL); + if (IS_ERR(rng_clk)) { + dev_warn(&pdev->dev, "no clk\n"); + return PTR_ERR(rng_clk); + } + + ret = clk_enable(rng_clk); + if (ret) { + dev_warn(&pdev->dev, "unable to enable clk\n"); + goto err_enable; + } + + picoxcell_trng_start(); + ret = hwrng_register(&picoxcell_trng); + if (ret) + goto err_register; + + rng_dev = &pdev->dev; + dev_info(&pdev->dev, "pixoxcell random number generator active\n"); + + return 0; + +err_register: + clk_disable(rng_clk); +err_enable: + clk_put(rng_clk); + + return ret; +} + +static int __devexit picoxcell_trng_remove(struct platform_device *pdev) +{ + hwrng_unregister(&picoxcell_trng); + clk_disable(rng_clk); + clk_put(rng_clk); + + return 0; +} + +#ifdef CONFIG_PM +static int picoxcell_trng_suspend(struct device *dev) +{ + clk_disable(rng_clk); + + return 0; +} + +static int picoxcell_trng_resume(struct device *dev) +{ + return clk_enable(rng_clk); +} + +static const struct dev_pm_ops picoxcell_trng_pm_ops = { + .suspend = picoxcell_trng_suspend, + .resume = picoxcell_trng_resume, +}; +#endif /* CONFIG_PM */ + +static struct platform_driver picoxcell_trng_driver = { + .probe = picoxcell_trng_probe, + .remove = __devexit_p(picoxcell_trng_remove), + .driver = { + .name = "picoxcell-trng", + .owner = THIS_MODULE, +#ifdef CONFIG_PM + .pm = &picoxcell_trng_pm_ops, +#endif /* CONFIG_PM */ + }, +}; + +static int __init picoxcell_trng_init(void) +{ + return platform_driver_register(&picoxcell_trng_driver); +} +module_init(picoxcell_trng_init); + +static void __exit picoxcell_trng_exit(void) +{ + platform_driver_unregister(&picoxcell_trng_driver); +} +module_exit(picoxcell_trng_exit); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("Jamie Iles"); +MODULE_DESCRIPTION("Picochip picoXcell TRNG driver"); diff --git a/drivers/char/random.c b/drivers/char/random.c index 72a4fcb1774..5e29e8031bb 100644 --- a/drivers/char/random.c +++ b/drivers/char/random.c @@ -128,6 +128,7 @@ * void add_input_randomness(unsigned int type, unsigned int code, * unsigned int value); * void add_interrupt_randomness(int irq); + * void add_disk_randomness(struct gendisk *disk); * * add_input_randomness() uses the input layer interrupt timing, as well as * the event type information from the hardware. @@ -136,9 +137,15 @@ * inputs to the entropy pool. Note that not all interrupts are good * sources of randomness! For example, the timer interrupts is not a * good choice, because the periodicity of the interrupts is too - * regular, and hence predictable to an attacker. Disk interrupts are - * a better measure, since the timing of the disk interrupts are more - * unpredictable. + * regular, and hence predictable to an attacker. Network Interface + * Controller interrupts are a better measure, since the timing of the + * NIC interrupts are more unpredictable. + * + * add_disk_randomness() uses what amounts to the seek time of block + * layer request events, on a per-disk_devt basis, as input to the + * entropy pool. Note that high-speed solid state drives with very low + * seek times do not make for good sources of entropy, as their seek + * times are usually fairly consistent. * * All of these routines try to estimate how many bits of randomness a * particular randomness source. They do this by keeping track of the |