Michael Buesch | ca644bd | 2006-06-26 00:24:59 -0700 | [diff] [blame] | 1 | /* |
| 2 | * RNG driver for Intel RNGs |
| 3 | * |
| 4 | * Copyright 2005 (c) MontaVista Software, Inc. |
| 5 | * |
| 6 | * with the majority of the code coming from: |
| 7 | * |
| 8 | * Hardware driver for the Intel/AMD/VIA Random Number Generators (RNG) |
| 9 | * (c) Copyright 2003 Red Hat Inc <jgarzik@redhat.com> |
| 10 | * |
| 11 | * derived from |
| 12 | * |
| 13 | * Hardware driver for the AMD 768 Random Number Generator (RNG) |
| 14 | * (c) Copyright 2001 Red Hat Inc <alan@redhat.com> |
| 15 | * |
| 16 | * derived from |
| 17 | * |
| 18 | * Hardware driver for Intel i810 Random Number Generator (RNG) |
| 19 | * Copyright 2000,2001 Jeff Garzik <jgarzik@pobox.com> |
| 20 | * Copyright 2000,2001 Philipp Rumpf <prumpf@mandrakesoft.com> |
| 21 | * |
| 22 | * This file is licensed under the terms of the GNU General Public |
| 23 | * License version 2. This program is licensed "as is" without any |
| 24 | * warranty of any kind, whether express or implied. |
| 25 | */ |
| 26 | |
Michael Buesch | ca644bd | 2006-06-26 00:24:59 -0700 | [diff] [blame] | 27 | #include <linux/hw_random.h> |
Prarit Bhargava | ee527cd | 2007-05-08 00:25:08 -0700 | [diff] [blame] | 28 | #include <linux/kernel.h> |
| 29 | #include <linux/module.h> |
| 30 | #include <linux/pci.h> |
| 31 | #include <linux/stop_machine.h> |
Patrick McHardy | 984e976 | 2007-11-21 12:24:45 +0800 | [diff] [blame] | 32 | #include <linux/delay.h> |
Michael Buesch | ca644bd | 2006-06-26 00:24:59 -0700 | [diff] [blame] | 33 | #include <asm/io.h> |
| 34 | |
| 35 | |
| 36 | #define PFX KBUILD_MODNAME ": " |
| 37 | |
| 38 | /* |
| 39 | * RNG registers |
| 40 | */ |
| 41 | #define INTEL_RNG_HW_STATUS 0 |
| 42 | #define INTEL_RNG_PRESENT 0x40 |
| 43 | #define INTEL_RNG_ENABLED 0x01 |
| 44 | #define INTEL_RNG_STATUS 1 |
| 45 | #define INTEL_RNG_DATA_PRESENT 0x01 |
| 46 | #define INTEL_RNG_DATA 2 |
| 47 | |
| 48 | /* |
| 49 | * Magic address at which Intel PCI bridges locate the RNG |
| 50 | */ |
| 51 | #define INTEL_RNG_ADDR 0xFFBC015F |
| 52 | #define INTEL_RNG_ADDR_LEN 3 |
| 53 | |
| 54 | /* |
Jan Beulich | c24c95a | 2006-09-29 01:59:42 -0700 | [diff] [blame] | 55 | * LPC bridge PCI config space registers |
| 56 | */ |
| 57 | #define FWH_DEC_EN1_REG_OLD 0xe3 |
| 58 | #define FWH_DEC_EN1_REG_NEW 0xd9 /* high byte of 16-bit register */ |
| 59 | #define FWH_F8_EN_MASK 0x80 |
| 60 | |
| 61 | #define BIOS_CNTL_REG_OLD 0x4e |
| 62 | #define BIOS_CNTL_REG_NEW 0xdc |
| 63 | #define BIOS_CNTL_WRITE_ENABLE_MASK 0x01 |
| 64 | #define BIOS_CNTL_LOCK_ENABLE_MASK 0x02 |
| 65 | |
| 66 | /* |
| 67 | * Magic address at which Intel Firmware Hubs get accessed |
| 68 | */ |
| 69 | #define INTEL_FWH_ADDR 0xffff0000 |
| 70 | #define INTEL_FWH_ADDR_LEN 2 |
| 71 | |
| 72 | /* |
| 73 | * Intel Firmware Hub command codes (write to any address inside the device) |
| 74 | */ |
| 75 | #define INTEL_FWH_RESET_CMD 0xff /* aka READ_ARRAY */ |
| 76 | #define INTEL_FWH_READ_ID_CMD 0x90 |
| 77 | |
| 78 | /* |
| 79 | * Intel Firmware Hub Read ID command result addresses |
| 80 | */ |
| 81 | #define INTEL_FWH_MANUFACTURER_CODE_ADDRESS 0x000000 |
| 82 | #define INTEL_FWH_DEVICE_CODE_ADDRESS 0x000001 |
| 83 | |
| 84 | /* |
| 85 | * Intel Firmware Hub Read ID command result values |
| 86 | */ |
| 87 | #define INTEL_FWH_MANUFACTURER_CODE 0x89 |
| 88 | #define INTEL_FWH_DEVICE_CODE_8M 0xac |
| 89 | #define INTEL_FWH_DEVICE_CODE_4M 0xad |
| 90 | |
| 91 | /* |
Michael Buesch | ca644bd | 2006-06-26 00:24:59 -0700 | [diff] [blame] | 92 | * Data for PCI driver interface |
| 93 | * |
| 94 | * This data only exists for exporting the supported |
| 95 | * PCI ids via MODULE_DEVICE_TABLE. We do not actually |
| 96 | * register a pci_driver, because someone else might one day |
| 97 | * want to register another driver on the same PCI id. |
| 98 | */ |
| 99 | static const struct pci_device_id pci_tbl[] = { |
Jan Beulich | c24c95a | 2006-09-29 01:59:42 -0700 | [diff] [blame] | 100 | /* AA |
Jiri Slaby | 29d73aa | 2007-02-12 00:51:48 -0800 | [diff] [blame] | 101 | { PCI_DEVICE(0x8086, 0x2418) }, */ |
| 102 | { PCI_DEVICE(0x8086, 0x2410) }, /* AA */ |
Jan Beulich | c24c95a | 2006-09-29 01:59:42 -0700 | [diff] [blame] | 103 | /* AB |
Jiri Slaby | 29d73aa | 2007-02-12 00:51:48 -0800 | [diff] [blame] | 104 | { PCI_DEVICE(0x8086, 0x2428) }, */ |
| 105 | { PCI_DEVICE(0x8086, 0x2420) }, /* AB */ |
Jan Beulich | c24c95a | 2006-09-29 01:59:42 -0700 | [diff] [blame] | 106 | /* ?? |
Jiri Slaby | 29d73aa | 2007-02-12 00:51:48 -0800 | [diff] [blame] | 107 | { PCI_DEVICE(0x8086, 0x2430) }, */ |
Jan Beulich | c24c95a | 2006-09-29 01:59:42 -0700 | [diff] [blame] | 108 | /* BAM, CAM, DBM, FBM, GxM |
Jiri Slaby | 29d73aa | 2007-02-12 00:51:48 -0800 | [diff] [blame] | 109 | { PCI_DEVICE(0x8086, 0x2448) }, */ |
| 110 | { PCI_DEVICE(0x8086, 0x244c) }, /* BAM */ |
| 111 | { PCI_DEVICE(0x8086, 0x248c) }, /* CAM */ |
| 112 | { PCI_DEVICE(0x8086, 0x24cc) }, /* DBM */ |
| 113 | { PCI_DEVICE(0x8086, 0x2641) }, /* FBM */ |
| 114 | { PCI_DEVICE(0x8086, 0x27b9) }, /* GxM */ |
| 115 | { PCI_DEVICE(0x8086, 0x27bd) }, /* GxM DH */ |
Jan Beulich | c24c95a | 2006-09-29 01:59:42 -0700 | [diff] [blame] | 116 | /* BA, CA, DB, Ex, 6300, Fx, 631x/632x, Gx |
Jiri Slaby | 29d73aa | 2007-02-12 00:51:48 -0800 | [diff] [blame] | 117 | { PCI_DEVICE(0x8086, 0x244e) }, */ |
| 118 | { PCI_DEVICE(0x8086, 0x2440) }, /* BA */ |
| 119 | { PCI_DEVICE(0x8086, 0x2480) }, /* CA */ |
| 120 | { PCI_DEVICE(0x8086, 0x24c0) }, /* DB */ |
| 121 | { PCI_DEVICE(0x8086, 0x24d0) }, /* Ex */ |
| 122 | { PCI_DEVICE(0x8086, 0x25a1) }, /* 6300 */ |
| 123 | { PCI_DEVICE(0x8086, 0x2640) }, /* Fx */ |
| 124 | { PCI_DEVICE(0x8086, 0x2670) }, /* 631x/632x */ |
| 125 | { PCI_DEVICE(0x8086, 0x2671) }, /* 631x/632x */ |
| 126 | { PCI_DEVICE(0x8086, 0x2672) }, /* 631x/632x */ |
| 127 | { PCI_DEVICE(0x8086, 0x2673) }, /* 631x/632x */ |
| 128 | { PCI_DEVICE(0x8086, 0x2674) }, /* 631x/632x */ |
| 129 | { PCI_DEVICE(0x8086, 0x2675) }, /* 631x/632x */ |
| 130 | { PCI_DEVICE(0x8086, 0x2676) }, /* 631x/632x */ |
| 131 | { PCI_DEVICE(0x8086, 0x2677) }, /* 631x/632x */ |
| 132 | { PCI_DEVICE(0x8086, 0x2678) }, /* 631x/632x */ |
| 133 | { PCI_DEVICE(0x8086, 0x2679) }, /* 631x/632x */ |
| 134 | { PCI_DEVICE(0x8086, 0x267a) }, /* 631x/632x */ |
| 135 | { PCI_DEVICE(0x8086, 0x267b) }, /* 631x/632x */ |
| 136 | { PCI_DEVICE(0x8086, 0x267c) }, /* 631x/632x */ |
| 137 | { PCI_DEVICE(0x8086, 0x267d) }, /* 631x/632x */ |
| 138 | { PCI_DEVICE(0x8086, 0x267e) }, /* 631x/632x */ |
| 139 | { PCI_DEVICE(0x8086, 0x267f) }, /* 631x/632x */ |
| 140 | { PCI_DEVICE(0x8086, 0x27b8) }, /* Gx */ |
Jan Beulich | c24c95a | 2006-09-29 01:59:42 -0700 | [diff] [blame] | 141 | /* E |
Jiri Slaby | 29d73aa | 2007-02-12 00:51:48 -0800 | [diff] [blame] | 142 | { PCI_DEVICE(0x8086, 0x245e) }, */ |
| 143 | { PCI_DEVICE(0x8086, 0x2450) }, /* E */ |
Michael Buesch | ca644bd | 2006-06-26 00:24:59 -0700 | [diff] [blame] | 144 | { 0, }, /* terminate list */ |
| 145 | }; |
| 146 | MODULE_DEVICE_TABLE(pci, pci_tbl); |
| 147 | |
Jan Beulich | 9863be5 | 2007-01-10 23:15:41 -0800 | [diff] [blame] | 148 | static __initdata int no_fwh_detect; |
| 149 | module_param(no_fwh_detect, int, 0); |
| 150 | MODULE_PARM_DESC(no_fwh_detect, "Skip FWH detection:\n" |
| 151 | " positive value - skip if FWH space locked read-only\n" |
| 152 | " negative value - skip always"); |
Michael Buesch | ca644bd | 2006-06-26 00:24:59 -0700 | [diff] [blame] | 153 | |
| 154 | static inline u8 hwstatus_get(void __iomem *mem) |
| 155 | { |
| 156 | return readb(mem + INTEL_RNG_HW_STATUS); |
| 157 | } |
| 158 | |
| 159 | static inline u8 hwstatus_set(void __iomem *mem, |
| 160 | u8 hw_status) |
| 161 | { |
| 162 | writeb(hw_status, mem + INTEL_RNG_HW_STATUS); |
| 163 | return hwstatus_get(mem); |
| 164 | } |
| 165 | |
Patrick McHardy | 984e976 | 2007-11-21 12:24:45 +0800 | [diff] [blame] | 166 | static int intel_rng_data_present(struct hwrng *rng, int wait) |
Michael Buesch | ca644bd | 2006-06-26 00:24:59 -0700 | [diff] [blame] | 167 | { |
| 168 | void __iomem *mem = (void __iomem *)rng->priv; |
Patrick McHardy | 984e976 | 2007-11-21 12:24:45 +0800 | [diff] [blame] | 169 | int data, i; |
Michael Buesch | ca644bd | 2006-06-26 00:24:59 -0700 | [diff] [blame] | 170 | |
Patrick McHardy | 984e976 | 2007-11-21 12:24:45 +0800 | [diff] [blame] | 171 | for (i = 0; i < 20; i++) { |
| 172 | data = !!(readb(mem + INTEL_RNG_STATUS) & |
| 173 | INTEL_RNG_DATA_PRESENT); |
| 174 | if (data || !wait) |
| 175 | break; |
| 176 | udelay(10); |
| 177 | } |
| 178 | return data; |
Michael Buesch | ca644bd | 2006-06-26 00:24:59 -0700 | [diff] [blame] | 179 | } |
| 180 | |
| 181 | static int intel_rng_data_read(struct hwrng *rng, u32 *data) |
| 182 | { |
| 183 | void __iomem *mem = (void __iomem *)rng->priv; |
| 184 | |
| 185 | *data = readb(mem + INTEL_RNG_DATA); |
| 186 | |
| 187 | return 1; |
| 188 | } |
| 189 | |
| 190 | static int intel_rng_init(struct hwrng *rng) |
| 191 | { |
| 192 | void __iomem *mem = (void __iomem *)rng->priv; |
| 193 | u8 hw_status; |
| 194 | int err = -EIO; |
| 195 | |
| 196 | hw_status = hwstatus_get(mem); |
| 197 | /* turn RNG h/w on, if it's off */ |
| 198 | if ((hw_status & INTEL_RNG_ENABLED) == 0) |
| 199 | hw_status = hwstatus_set(mem, hw_status | INTEL_RNG_ENABLED); |
| 200 | if ((hw_status & INTEL_RNG_ENABLED) == 0) { |
| 201 | printk(KERN_ERR PFX "cannot enable RNG, aborting\n"); |
| 202 | goto out; |
| 203 | } |
| 204 | err = 0; |
| 205 | out: |
| 206 | return err; |
| 207 | } |
| 208 | |
| 209 | static void intel_rng_cleanup(struct hwrng *rng) |
| 210 | { |
| 211 | void __iomem *mem = (void __iomem *)rng->priv; |
| 212 | u8 hw_status; |
| 213 | |
| 214 | hw_status = hwstatus_get(mem); |
| 215 | if (hw_status & INTEL_RNG_ENABLED) |
| 216 | hwstatus_set(mem, hw_status & ~INTEL_RNG_ENABLED); |
| 217 | else |
| 218 | printk(KERN_WARNING PFX "unusual: RNG already disabled\n"); |
| 219 | } |
| 220 | |
| 221 | |
| 222 | static struct hwrng intel_rng = { |
| 223 | .name = "intel", |
| 224 | .init = intel_rng_init, |
| 225 | .cleanup = intel_rng_cleanup, |
| 226 | .data_present = intel_rng_data_present, |
| 227 | .data_read = intel_rng_data_read, |
| 228 | }; |
| 229 | |
Prarit Bhargava | ee527cd | 2007-05-08 00:25:08 -0700 | [diff] [blame] | 230 | struct intel_rng_hw { |
| 231 | struct pci_dev *dev; |
| 232 | void __iomem *mem; |
| 233 | u8 bios_cntl_off; |
| 234 | u8 bios_cntl_val; |
| 235 | u8 fwh_dec_en1_off; |
| 236 | u8 fwh_dec_en1_val; |
| 237 | }; |
Michael Buesch | ca644bd | 2006-06-26 00:24:59 -0700 | [diff] [blame] | 238 | |
Prarit Bhargava | ee527cd | 2007-05-08 00:25:08 -0700 | [diff] [blame] | 239 | static int __init intel_rng_hw_init(void *_intel_rng_hw) |
Jan Beulich | c24c95a | 2006-09-29 01:59:42 -0700 | [diff] [blame] | 240 | { |
Prarit Bhargava | ee527cd | 2007-05-08 00:25:08 -0700 | [diff] [blame] | 241 | struct intel_rng_hw *intel_rng_hw = _intel_rng_hw; |
| 242 | u8 mfc, dvc; |
| 243 | |
| 244 | /* interrupts disabled in stop_machine_run call */ |
| 245 | |
| 246 | if (!(intel_rng_hw->fwh_dec_en1_val & FWH_F8_EN_MASK)) |
| 247 | pci_write_config_byte(intel_rng_hw->dev, |
| 248 | intel_rng_hw->fwh_dec_en1_off, |
| 249 | intel_rng_hw->fwh_dec_en1_val | |
| 250 | FWH_F8_EN_MASK); |
| 251 | if (!(intel_rng_hw->bios_cntl_val & BIOS_CNTL_WRITE_ENABLE_MASK)) |
| 252 | pci_write_config_byte(intel_rng_hw->dev, |
| 253 | intel_rng_hw->bios_cntl_off, |
| 254 | intel_rng_hw->bios_cntl_val | |
| 255 | BIOS_CNTL_WRITE_ENABLE_MASK); |
| 256 | |
| 257 | writeb(INTEL_FWH_RESET_CMD, intel_rng_hw->mem); |
| 258 | writeb(INTEL_FWH_READ_ID_CMD, intel_rng_hw->mem); |
| 259 | mfc = readb(intel_rng_hw->mem + INTEL_FWH_MANUFACTURER_CODE_ADDRESS); |
| 260 | dvc = readb(intel_rng_hw->mem + INTEL_FWH_DEVICE_CODE_ADDRESS); |
| 261 | writeb(INTEL_FWH_RESET_CMD, intel_rng_hw->mem); |
| 262 | |
| 263 | if (!(intel_rng_hw->bios_cntl_val & |
| 264 | (BIOS_CNTL_LOCK_ENABLE_MASK|BIOS_CNTL_WRITE_ENABLE_MASK))) |
| 265 | pci_write_config_byte(intel_rng_hw->dev, |
| 266 | intel_rng_hw->bios_cntl_off, |
| 267 | intel_rng_hw->bios_cntl_val); |
| 268 | if (!(intel_rng_hw->fwh_dec_en1_val & FWH_F8_EN_MASK)) |
| 269 | pci_write_config_byte(intel_rng_hw->dev, |
| 270 | intel_rng_hw->fwh_dec_en1_off, |
| 271 | intel_rng_hw->fwh_dec_en1_val); |
| 272 | |
| 273 | if (mfc != INTEL_FWH_MANUFACTURER_CODE || |
| 274 | (dvc != INTEL_FWH_DEVICE_CODE_8M && |
| 275 | dvc != INTEL_FWH_DEVICE_CODE_4M)) { |
Stephen Hemminger | c97aee9 | 2008-06-12 15:21:45 -0700 | [diff] [blame^] | 276 | printk(KERN_NOTICE PFX "FWH not detected\n"); |
Prarit Bhargava | ee527cd | 2007-05-08 00:25:08 -0700 | [diff] [blame] | 277 | return -ENODEV; |
| 278 | } |
| 279 | |
| 280 | return 0; |
Jan Beulich | c24c95a | 2006-09-29 01:59:42 -0700 | [diff] [blame] | 281 | } |
Prarit Bhargava | ee527cd | 2007-05-08 00:25:08 -0700 | [diff] [blame] | 282 | |
| 283 | static int __init intel_init_hw_struct(struct intel_rng_hw *intel_rng_hw, |
| 284 | struct pci_dev *dev) |
| 285 | { |
| 286 | intel_rng_hw->bios_cntl_val = 0xff; |
| 287 | intel_rng_hw->fwh_dec_en1_val = 0xff; |
| 288 | intel_rng_hw->dev = dev; |
| 289 | |
| 290 | /* Check for Intel 82802 */ |
| 291 | if (dev->device < 0x2640) { |
| 292 | intel_rng_hw->fwh_dec_en1_off = FWH_DEC_EN1_REG_OLD; |
| 293 | intel_rng_hw->bios_cntl_off = BIOS_CNTL_REG_OLD; |
| 294 | } else { |
| 295 | intel_rng_hw->fwh_dec_en1_off = FWH_DEC_EN1_REG_NEW; |
| 296 | intel_rng_hw->bios_cntl_off = BIOS_CNTL_REG_NEW; |
| 297 | } |
| 298 | |
| 299 | pci_read_config_byte(dev, intel_rng_hw->fwh_dec_en1_off, |
| 300 | &intel_rng_hw->fwh_dec_en1_val); |
| 301 | pci_read_config_byte(dev, intel_rng_hw->bios_cntl_off, |
| 302 | &intel_rng_hw->bios_cntl_val); |
| 303 | |
| 304 | if ((intel_rng_hw->bios_cntl_val & |
| 305 | (BIOS_CNTL_LOCK_ENABLE_MASK|BIOS_CNTL_WRITE_ENABLE_MASK)) |
| 306 | == BIOS_CNTL_LOCK_ENABLE_MASK) { |
| 307 | static __initdata /*const*/ char warning[] = |
Alan Cox | f3dc8c1 | 2007-07-15 23:40:54 -0700 | [diff] [blame] | 308 | KERN_WARNING PFX "Firmware space is locked read-only. If you can't or\n" |
| 309 | KERN_WARNING PFX "don't want to disable this in firmware setup, and if\n" |
| 310 | KERN_WARNING PFX "you are certain that your system has a functional\n" |
| 311 | KERN_WARNING PFX "RNG, try using the 'no_fwh_detect' option.\n"; |
Prarit Bhargava | ee527cd | 2007-05-08 00:25:08 -0700 | [diff] [blame] | 312 | |
| 313 | if (no_fwh_detect) |
| 314 | return -ENODEV; |
| 315 | printk(warning); |
| 316 | return -EBUSY; |
| 317 | } |
| 318 | |
| 319 | intel_rng_hw->mem = ioremap_nocache(INTEL_FWH_ADDR, INTEL_FWH_ADDR_LEN); |
| 320 | if (intel_rng_hw->mem == NULL) |
| 321 | return -EBUSY; |
| 322 | |
| 323 | return 0; |
| 324 | } |
| 325 | |
Jan Beulich | c24c95a | 2006-09-29 01:59:42 -0700 | [diff] [blame] | 326 | |
Michael Buesch | ca644bd | 2006-06-26 00:24:59 -0700 | [diff] [blame] | 327 | static int __init mod_init(void) |
| 328 | { |
| 329 | int err = -ENODEV; |
Prarit Bhargava | ee527cd | 2007-05-08 00:25:08 -0700 | [diff] [blame] | 330 | int i; |
Jan Beulich | c24c95a | 2006-09-29 01:59:42 -0700 | [diff] [blame] | 331 | struct pci_dev *dev = NULL; |
Prarit Bhargava | ee527cd | 2007-05-08 00:25:08 -0700 | [diff] [blame] | 332 | void __iomem *mem = mem; |
| 333 | u8 hw_status; |
| 334 | struct intel_rng_hw *intel_rng_hw; |
Michael Buesch | ca644bd | 2006-06-26 00:24:59 -0700 | [diff] [blame] | 335 | |
Jan Beulich | c24c95a | 2006-09-29 01:59:42 -0700 | [diff] [blame] | 336 | for (i = 0; !dev && pci_tbl[i].vendor; ++i) |
Prarit Bhargava | ee527cd | 2007-05-08 00:25:08 -0700 | [diff] [blame] | 337 | dev = pci_get_device(pci_tbl[i].vendor, pci_tbl[i].device, |
| 338 | NULL); |
Jan Beulich | c24c95a | 2006-09-29 01:59:42 -0700 | [diff] [blame] | 339 | |
| 340 | if (!dev) |
Michael Buesch | ca644bd | 2006-06-26 00:24:59 -0700 | [diff] [blame] | 341 | goto out; /* Device not found. */ |
| 342 | |
Jan Beulich | 9863be5 | 2007-01-10 23:15:41 -0800 | [diff] [blame] | 343 | if (no_fwh_detect < 0) { |
| 344 | pci_dev_put(dev); |
| 345 | goto fwh_done; |
| 346 | } |
| 347 | |
Prarit Bhargava | ee527cd | 2007-05-08 00:25:08 -0700 | [diff] [blame] | 348 | intel_rng_hw = kmalloc(sizeof(*intel_rng_hw), GFP_KERNEL); |
| 349 | if (!intel_rng_hw) { |
Jan Beulich | 9863be5 | 2007-01-10 23:15:41 -0800 | [diff] [blame] | 350 | pci_dev_put(dev); |
Jan Beulich | 9863be5 | 2007-01-10 23:15:41 -0800 | [diff] [blame] | 351 | goto out; |
| 352 | } |
| 353 | |
Prarit Bhargava | ee527cd | 2007-05-08 00:25:08 -0700 | [diff] [blame] | 354 | err = intel_init_hw_struct(intel_rng_hw, dev); |
| 355 | if (err) { |
Jan Beulich | c24c95a | 2006-09-29 01:59:42 -0700 | [diff] [blame] | 356 | pci_dev_put(dev); |
Prarit Bhargava | ee527cd | 2007-05-08 00:25:08 -0700 | [diff] [blame] | 357 | kfree(intel_rng_hw); |
| 358 | if (err == -ENODEV) |
| 359 | goto fwh_done; |
Jan Beulich | c24c95a | 2006-09-29 01:59:42 -0700 | [diff] [blame] | 360 | goto out; |
| 361 | } |
| 362 | |
| 363 | /* |
| 364 | * Since the BIOS code/data is going to disappear from its normal |
| 365 | * location with the Read ID command, all activity on the system |
| 366 | * must be stopped until the state is back to normal. |
Prarit Bhargava | ee527cd | 2007-05-08 00:25:08 -0700 | [diff] [blame] | 367 | * |
| 368 | * Use stop_machine_run because IPIs can be blocked by disabling |
| 369 | * interrupts. |
Jan Beulich | c24c95a | 2006-09-29 01:59:42 -0700 | [diff] [blame] | 370 | */ |
Prarit Bhargava | ee527cd | 2007-05-08 00:25:08 -0700 | [diff] [blame] | 371 | err = stop_machine_run(intel_rng_hw_init, intel_rng_hw, NR_CPUS); |
Jan Beulich | c24c95a | 2006-09-29 01:59:42 -0700 | [diff] [blame] | 372 | pci_dev_put(dev); |
Prarit Bhargava | ee527cd | 2007-05-08 00:25:08 -0700 | [diff] [blame] | 373 | iounmap(intel_rng_hw->mem); |
| 374 | kfree(intel_rng_hw); |
| 375 | if (err) |
Jan Beulich | c24c95a | 2006-09-29 01:59:42 -0700 | [diff] [blame] | 376 | goto out; |
Jan Beulich | c24c95a | 2006-09-29 01:59:42 -0700 | [diff] [blame] | 377 | |
Jan Beulich | 9863be5 | 2007-01-10 23:15:41 -0800 | [diff] [blame] | 378 | fwh_done: |
Michael Buesch | ca644bd | 2006-06-26 00:24:59 -0700 | [diff] [blame] | 379 | err = -ENOMEM; |
| 380 | mem = ioremap(INTEL_RNG_ADDR, INTEL_RNG_ADDR_LEN); |
| 381 | if (!mem) |
| 382 | goto out; |
| 383 | intel_rng.priv = (unsigned long)mem; |
| 384 | |
Jan Beulich | c24c95a | 2006-09-29 01:59:42 -0700 | [diff] [blame] | 385 | /* Check for Random Number Generator */ |
Michael Buesch | ca644bd | 2006-06-26 00:24:59 -0700 | [diff] [blame] | 386 | err = -ENODEV; |
| 387 | hw_status = hwstatus_get(mem); |
Prarit Bhargava | ee527cd | 2007-05-08 00:25:08 -0700 | [diff] [blame] | 388 | if ((hw_status & INTEL_RNG_PRESENT) == 0) { |
| 389 | iounmap(mem); |
| 390 | goto out; |
| 391 | } |
Michael Buesch | ca644bd | 2006-06-26 00:24:59 -0700 | [diff] [blame] | 392 | |
| 393 | printk(KERN_INFO "Intel 82802 RNG detected\n"); |
| 394 | err = hwrng_register(&intel_rng); |
| 395 | if (err) { |
| 396 | printk(KERN_ERR PFX "RNG registering failed (%d)\n", |
| 397 | err); |
Prarit Bhargava | ee527cd | 2007-05-08 00:25:08 -0700 | [diff] [blame] | 398 | iounmap(mem); |
Michael Buesch | ca644bd | 2006-06-26 00:24:59 -0700 | [diff] [blame] | 399 | } |
| 400 | out: |
| 401 | return err; |
| 402 | |
Michael Buesch | ca644bd | 2006-06-26 00:24:59 -0700 | [diff] [blame] | 403 | } |
| 404 | |
| 405 | static void __exit mod_exit(void) |
| 406 | { |
| 407 | void __iomem *mem = (void __iomem *)intel_rng.priv; |
| 408 | |
| 409 | hwrng_unregister(&intel_rng); |
| 410 | iounmap(mem); |
| 411 | } |
| 412 | |
Michael Buesch | 56fb5fe | 2007-01-10 23:15:43 -0800 | [diff] [blame] | 413 | module_init(mod_init); |
Michael Buesch | ca644bd | 2006-06-26 00:24:59 -0700 | [diff] [blame] | 414 | module_exit(mod_exit); |
| 415 | |
| 416 | MODULE_DESCRIPTION("H/W RNG driver for Intel chipsets"); |
| 417 | MODULE_LICENSE("GPL"); |