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authorLinus Torvalds <torvalds@linux-foundation.org>2011-03-16 12:15:21 -0400
committerLinus Torvalds <torvalds@linux-foundation.org>2011-03-16 12:15:21 -0400
commit0d2ecee2bdb2a19d04bc5cefac0f86e790f1aad4 (patch)
tree2e0f08819a57e2c191f6e7fe2b2cd2f2415143bd /drivers/char
parent3ae2a1ce2e7b70254e5c9e465adefac9cba191d6 (diff)
parentf07ef1de9baeb2add514c51f59d4bc3c659c2ca4 (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/Kconfig12
-rw-r--r--drivers/char/hw_random/Makefile1
-rw-r--r--drivers/char/hw_random/omap-rng.c14
-rw-r--r--drivers/char/hw_random/picoxcell-rng.c208
-rw-r--r--drivers/char/random.c13
5 files changed, 237 insertions, 11 deletions
diff --git a/drivers/char/hw_random/Kconfig b/drivers/char/hw_random/Kconfig
index d31483c54883..beecd1cf9b99 100644
--- a/drivers/char/hw_random/Kconfig
+++ b/drivers/char/hw_random/Kconfig
@@ -198,3 +198,15 @@ config HW_RANDOM_NOMADIK
198 module will be called nomadik-rng. 198 module will be called nomadik-rng.
199 199
200 If unsure, say Y. 200 If unsure, say Y.
201
202config HW_RANDOM_PICOXCELL
203 tristate "Picochip picoXcell true random number generator support"
204 depends on HW_RANDOM && ARCH_PICOXCELL && PICOXCELL_PC3X3
205 ---help---
206 This driver provides kernel-side support for the Random Number
207 Generator hardware found on Picochip PC3x3 and later devices.
208
209 To compile this driver as a module, choose M here: the
210 module will be called picoxcell-rng.
211
212 If unsure, say Y.
diff --git a/drivers/char/hw_random/Makefile b/drivers/char/hw_random/Makefile
index 4273308aa1e3..3db4eb8b19c0 100644
--- a/drivers/char/hw_random/Makefile
+++ b/drivers/char/hw_random/Makefile
@@ -19,3 +19,4 @@ obj-$(CONFIG_HW_RANDOM_TX4939) += tx4939-rng.o
19obj-$(CONFIG_HW_RANDOM_MXC_RNGA) += mxc-rnga.o 19obj-$(CONFIG_HW_RANDOM_MXC_RNGA) += mxc-rnga.o
20obj-$(CONFIG_HW_RANDOM_OCTEON) += octeon-rng.o 20obj-$(CONFIG_HW_RANDOM_OCTEON) += octeon-rng.o
21obj-$(CONFIG_HW_RANDOM_NOMADIK) += nomadik-rng.o 21obj-$(CONFIG_HW_RANDOM_NOMADIK) += nomadik-rng.o
22obj-$(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 06aad0831c73..2cc755a64302 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 = {
91 91
92static int __devinit omap_rng_probe(struct platform_device *pdev) 92static int __devinit omap_rng_probe(struct platform_device *pdev)
93{ 93{
94 struct resource *res, *mem; 94 struct resource *res;
95 int ret; 95 int ret;
96 96
97 /* 97 /*
@@ -116,14 +116,12 @@ static int __devinit omap_rng_probe(struct platform_device *pdev)
116 if (!res) 116 if (!res)
117 return -ENOENT; 117 return -ENOENT;
118 118
119 mem = request_mem_region(res->start, resource_size(res), 119 if (!request_mem_region(res->start, resource_size(res), pdev->name)) {
120 pdev->name);
121 if (mem == NULL) {
122 ret = -EBUSY; 120 ret = -EBUSY;
123 goto err_region; 121 goto err_region;
124 } 122 }
125 123
126 dev_set_drvdata(&pdev->dev, mem); 124 dev_set_drvdata(&pdev->dev, res);
127 rng_base = ioremap(res->start, resource_size(res)); 125 rng_base = ioremap(res->start, resource_size(res));
128 if (!rng_base) { 126 if (!rng_base) {
129 ret = -ENOMEM; 127 ret = -ENOMEM;
@@ -146,7 +144,7 @@ err_register:
146 iounmap(rng_base); 144 iounmap(rng_base);
147 rng_base = NULL; 145 rng_base = NULL;
148err_ioremap: 146err_ioremap:
149 release_resource(mem); 147 release_mem_region(res->start, resource_size(res));
150err_region: 148err_region:
151 if (cpu_is_omap24xx()) { 149 if (cpu_is_omap24xx()) {
152 clk_disable(rng_ick); 150 clk_disable(rng_ick);
@@ -157,7 +155,7 @@ err_region:
157 155
158static int __exit omap_rng_remove(struct platform_device *pdev) 156static int __exit omap_rng_remove(struct platform_device *pdev)
159{ 157{
160 struct resource *mem = dev_get_drvdata(&pdev->dev); 158 struct resource *res = dev_get_drvdata(&pdev->dev);
161 159
162 hwrng_unregister(&omap_rng_ops); 160 hwrng_unregister(&omap_rng_ops);
163 161
@@ -170,7 +168,7 @@ static int __exit omap_rng_remove(struct platform_device *pdev)
170 clk_put(rng_ick); 168 clk_put(rng_ick);
171 } 169 }
172 170
173 release_resource(mem); 171 release_mem_region(res->start, resource_size(res));
174 rng_base = NULL; 172 rng_base = NULL;
175 173
176 return 0; 174 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 000000000000..990d55a5e3e8
--- /dev/null
+++ b/drivers/char/hw_random/picoxcell-rng.c
@@ -0,0 +1,208 @@
1/*
2 * Copyright (c) 2010-2011 Picochip Ltd., Jamie Iles
3 *
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
7 *
8 * All enquiries to support@picochip.com
9 */
10#include <linux/clk.h>
11#include <linux/delay.h>
12#include <linux/err.h>
13#include <linux/hw_random.h>
14#include <linux/io.h>
15#include <linux/kernel.h>
16#include <linux/module.h>
17#include <linux/platform_device.h>
18
19#define DATA_REG_OFFSET 0x0200
20#define CSR_REG_OFFSET 0x0278
21#define CSR_OUT_EMPTY_MASK (1 << 24)
22#define CSR_FAULT_MASK (1 << 1)
23#define TRNG_BLOCK_RESET_MASK (1 << 0)
24#define TAI_REG_OFFSET 0x0380
25
26/*
27 * The maximum amount of time in microseconds to spend waiting for data if the
28 * core wants us to wait. The TRNG should generate 32 bits every 320ns so a
29 * timeout of 20us seems reasonable. The TRNG does builtin tests of the data
30 * for randomness so we can't always assume there is data present.
31 */
32#define PICO_TRNG_TIMEOUT 20
33
34static void __iomem *rng_base;
35static struct clk *rng_clk;
36struct device *rng_dev;
37
38static inline u32 picoxcell_trng_read_csr(void)
39{
40 return __raw_readl(rng_base + CSR_REG_OFFSET);
41}
42
43static inline bool picoxcell_trng_is_empty(void)
44{
45 return picoxcell_trng_read_csr() & CSR_OUT_EMPTY_MASK;
46}
47
48/*
49 * Take the random number generator out of reset and make sure the interrupts
50 * are masked. We shouldn't need to get large amounts of random bytes so just
51 * poll the status register. The hardware generates 32 bits every 320ns so we
52 * shouldn't have to wait long enough to warrant waiting for an IRQ.
53 */
54static void picoxcell_trng_start(void)
55{
56 __raw_writel(0, rng_base + TAI_REG_OFFSET);
57 __raw_writel(0, rng_base + CSR_REG_OFFSET);
58}
59
60static void picoxcell_trng_reset(void)
61{
62 __raw_writel(TRNG_BLOCK_RESET_MASK, rng_base + CSR_REG_OFFSET);
63 __raw_writel(TRNG_BLOCK_RESET_MASK, rng_base + TAI_REG_OFFSET);
64 picoxcell_trng_start();
65}
66
67/*
68 * Get some random data from the random number generator. The hw_random core
69 * layer provides us with locking.
70 */
71static int picoxcell_trng_read(struct hwrng *rng, void *buf, size_t max,
72 bool wait)
73{
74 int i;
75
76 /* Wait for some data to become available. */
77 for (i = 0; i < PICO_TRNG_TIMEOUT && picoxcell_trng_is_empty(); ++i) {
78 if (!wait)
79 return 0;
80
81 udelay(1);
82 }
83
84 if (picoxcell_trng_read_csr() & CSR_FAULT_MASK) {
85 dev_err(rng_dev, "fault detected, resetting TRNG\n");
86 picoxcell_trng_reset();
87 return -EIO;
88 }
89
90 if (i == PICO_TRNG_TIMEOUT)
91 return 0;
92
93 *(u32 *)buf = __raw_readl(rng_base + DATA_REG_OFFSET);
94 return sizeof(u32);
95}
96
97static struct hwrng picoxcell_trng = {
98 .name = "picoxcell",
99 .read = picoxcell_trng_read,
100};
101
102static int picoxcell_trng_probe(struct platform_device *pdev)
103{
104 int ret;
105 struct resource *mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
106
107 if (!mem) {
108 dev_warn(&pdev->dev, "no memory resource\n");
109 return -ENOMEM;
110 }
111
112 if (!devm_request_mem_region(&pdev->dev, mem->start, resource_size(mem),
113 "picoxcell_trng")) {
114 dev_warn(&pdev->dev, "unable to request io mem\n");
115 return -EBUSY;
116 }
117
118 rng_base = devm_ioremap(&pdev->dev, mem->start, resource_size(mem));
119 if (!rng_base) {
120 dev_warn(&pdev->dev, "unable to remap io mem\n");
121 return -ENOMEM;
122 }
123
124 rng_clk = clk_get(&pdev->dev, NULL);
125 if (IS_ERR(rng_clk)) {
126 dev_warn(&pdev->dev, "no clk\n");
127 return PTR_ERR(rng_clk);
128 }
129
130 ret = clk_enable(rng_clk);
131 if (ret) {
132 dev_warn(&pdev->dev, "unable to enable clk\n");
133 goto err_enable;
134 }
135
136 picoxcell_trng_start();
137 ret = hwrng_register(&picoxcell_trng);
138 if (ret)
139 goto err_register;
140
141 rng_dev = &pdev->dev;
142 dev_info(&pdev->dev, "pixoxcell random number generator active\n");
143
144 return 0;
145
146err_register:
147 clk_disable(rng_clk);
148err_enable:
149 clk_put(rng_clk);
150
151 return ret;
152}
153
154static int __devexit picoxcell_trng_remove(struct platform_device *pdev)
155{
156 hwrng_unregister(&picoxcell_trng);
157 clk_disable(rng_clk);
158 clk_put(rng_clk);
159
160 return 0;
161}
162
163#ifdef CONFIG_PM
164static int picoxcell_trng_suspend(struct device *dev)
165{
166 clk_disable(rng_clk);
167
168 return 0;
169}
170
171static int picoxcell_trng_resume(struct device *dev)
172{
173 return clk_enable(rng_clk);
174}
175
176static const struct dev_pm_ops picoxcell_trng_pm_ops = {
177 .suspend = picoxcell_trng_suspend,
178 .resume = picoxcell_trng_resume,
179};
180#endif /* CONFIG_PM */
181
182static struct platform_driver picoxcell_trng_driver = {
183 .probe = picoxcell_trng_probe,
184 .remove = __devexit_p(picoxcell_trng_remove),
185 .driver = {
186 .name = "picoxcell-trng",
187 .owner = THIS_MODULE,
188#ifdef CONFIG_PM
189 .pm = &picoxcell_trng_pm_ops,
190#endif /* CONFIG_PM */
191 },
192};
193
194static int __init picoxcell_trng_init(void)
195{
196 return platform_driver_register(&picoxcell_trng_driver);
197}
198module_init(picoxcell_trng_init);
199
200static void __exit picoxcell_trng_exit(void)
201{
202 platform_driver_unregister(&picoxcell_trng_driver);
203}
204module_exit(picoxcell_trng_exit);
205
206MODULE_LICENSE("GPL");
207MODULE_AUTHOR("Jamie Iles");
208MODULE_DESCRIPTION("Picochip picoXcell TRNG driver");
diff --git a/drivers/char/random.c b/drivers/char/random.c
index 72a4fcb17745..5e29e8031bbc 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -128,6 +128,7 @@
128 * void add_input_randomness(unsigned int type, unsigned int code, 128 * void add_input_randomness(unsigned int type, unsigned int code,
129 * unsigned int value); 129 * unsigned int value);
130 * void add_interrupt_randomness(int irq); 130 * void add_interrupt_randomness(int irq);
131 * void add_disk_randomness(struct gendisk *disk);
131 * 132 *
132 * add_input_randomness() uses the input layer interrupt timing, as well as 133 * add_input_randomness() uses the input layer interrupt timing, as well as
133 * the event type information from the hardware. 134 * the event type information from the hardware.
@@ -136,9 +137,15 @@
136 * inputs to the entropy pool. Note that not all interrupts are good 137 * inputs to the entropy pool. Note that not all interrupts are good
137 * sources of randomness! For example, the timer interrupts is not a 138 * sources of randomness! For example, the timer interrupts is not a
138 * good choice, because the periodicity of the interrupts is too 139 * good choice, because the periodicity of the interrupts is too
139 * regular, and hence predictable to an attacker. Disk interrupts are 140 * regular, and hence predictable to an attacker. Network Interface
140 * a better measure, since the timing of the disk interrupts are more 141 * Controller interrupts are a better measure, since the timing of the
141 * unpredictable. 142 * NIC interrupts are more unpredictable.
143 *
144 * add_disk_randomness() uses what amounts to the seek time of block
145 * layer request events, on a per-disk_devt basis, as input to the
146 * entropy pool. Note that high-speed solid state drives with very low
147 * seek times do not make for good sources of entropy, as their seek
148 * times are usually fairly consistent.
142 * 149 *
143 * All of these routines try to estimate how many bits of randomness a 150 * All of these routines try to estimate how many bits of randomness a
144 * particular randomness source. They do this by keeping track of the 151 * particular randomness source. They do this by keeping track of the