Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * BIOS32 and PCI BIOS handling. |
| 3 | */ |
| 4 | |
| 5 | #include <linux/pci.h> |
| 6 | #include <linux/init.h> |
Alexey Dobriyan | 129f694 | 2005-06-23 00:08:33 -0700 | [diff] [blame] | 7 | #include <linux/module.h> |
Rusty Russell | bd472c7 | 2006-12-07 02:14:08 +0100 | [diff] [blame] | 8 | #include <linux/uaccess.h> |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 9 | #include "pci.h" |
| 10 | #include "pci-functions.h" |
| 11 | |
| 12 | |
| 13 | /* BIOS32 signature: "_32_" */ |
| 14 | #define BIOS32_SIGNATURE (('_' << 0) + ('3' << 8) + ('2' << 16) + ('_' << 24)) |
| 15 | |
| 16 | /* PCI signature: "PCI " */ |
| 17 | #define PCI_SIGNATURE (('P' << 0) + ('C' << 8) + ('I' << 16) + (' ' << 24)) |
| 18 | |
| 19 | /* PCI service signature: "$PCI" */ |
| 20 | #define PCI_SERVICE (('$' << 0) + ('P' << 8) + ('C' << 16) + ('I' << 24)) |
| 21 | |
| 22 | /* PCI BIOS hardware mechanism flags */ |
| 23 | #define PCIBIOS_HW_TYPE1 0x01 |
| 24 | #define PCIBIOS_HW_TYPE2 0x02 |
| 25 | #define PCIBIOS_HW_TYPE1_SPEC 0x10 |
| 26 | #define PCIBIOS_HW_TYPE2_SPEC 0x20 |
| 27 | |
| 28 | /* |
| 29 | * This is the standard structure used to identify the entry point |
| 30 | * to the BIOS32 Service Directory, as documented in |
| 31 | * Standard BIOS 32-bit Service Directory Proposal |
| 32 | * Revision 0.4 May 24, 1993 |
| 33 | * Phoenix Technologies Ltd. |
| 34 | * Norwood, MA |
| 35 | * and the PCI BIOS specification. |
| 36 | */ |
| 37 | |
| 38 | union bios32 { |
| 39 | struct { |
| 40 | unsigned long signature; /* _32_ */ |
| 41 | unsigned long entry; /* 32 bit physical address */ |
| 42 | unsigned char revision; /* Revision level, 0 */ |
| 43 | unsigned char length; /* Length in paragraphs should be 01 */ |
| 44 | unsigned char checksum; /* All bytes must add up to zero */ |
| 45 | unsigned char reserved[5]; /* Must be zero */ |
| 46 | } fields; |
| 47 | char chars[16]; |
| 48 | }; |
| 49 | |
| 50 | /* |
| 51 | * Physical address of the service directory. I don't know if we're |
| 52 | * allowed to have more than one of these or not, so just in case |
| 53 | * we'll make pcibios_present() take a memory start parameter and store |
| 54 | * the array there. |
| 55 | */ |
| 56 | |
| 57 | static struct { |
| 58 | unsigned long address; |
| 59 | unsigned short segment; |
| 60 | } bios32_indirect = { 0, __KERNEL_CS }; |
| 61 | |
| 62 | /* |
| 63 | * Returns the entry point for the given service, NULL on error |
| 64 | */ |
| 65 | |
| 66 | static unsigned long bios32_service(unsigned long service) |
| 67 | { |
| 68 | unsigned char return_code; /* %al */ |
| 69 | unsigned long address; /* %ebx */ |
| 70 | unsigned long length; /* %ecx */ |
| 71 | unsigned long entry; /* %edx */ |
| 72 | unsigned long flags; |
| 73 | |
| 74 | local_irq_save(flags); |
| 75 | __asm__("lcall *(%%edi); cld" |
| 76 | : "=a" (return_code), |
| 77 | "=b" (address), |
| 78 | "=c" (length), |
| 79 | "=d" (entry) |
| 80 | : "0" (service), |
| 81 | "1" (0), |
| 82 | "D" (&bios32_indirect)); |
| 83 | local_irq_restore(flags); |
| 84 | |
| 85 | switch (return_code) { |
| 86 | case 0: |
| 87 | return address + entry; |
| 88 | case 0x80: /* Not present */ |
| 89 | printk(KERN_WARNING "bios32_service(0x%lx): not present\n", service); |
| 90 | return 0; |
| 91 | default: /* Shouldn't happen */ |
| 92 | printk(KERN_WARNING "bios32_service(0x%lx): returned 0x%x -- BIOS bug!\n", |
| 93 | service, return_code); |
| 94 | return 0; |
| 95 | } |
| 96 | } |
| 97 | |
| 98 | static struct { |
| 99 | unsigned long address; |
| 100 | unsigned short segment; |
| 101 | } pci_indirect = { 0, __KERNEL_CS }; |
| 102 | |
| 103 | static int pci_bios_present; |
| 104 | |
| 105 | static int __devinit check_pcibios(void) |
| 106 | { |
| 107 | u32 signature, eax, ebx, ecx; |
| 108 | u8 status, major_ver, minor_ver, hw_mech; |
| 109 | unsigned long flags, pcibios_entry; |
| 110 | |
| 111 | if ((pcibios_entry = bios32_service(PCI_SERVICE))) { |
| 112 | pci_indirect.address = pcibios_entry + PAGE_OFFSET; |
| 113 | |
| 114 | local_irq_save(flags); |
| 115 | __asm__( |
| 116 | "lcall *(%%edi); cld\n\t" |
| 117 | "jc 1f\n\t" |
| 118 | "xor %%ah, %%ah\n" |
| 119 | "1:" |
| 120 | : "=d" (signature), |
| 121 | "=a" (eax), |
| 122 | "=b" (ebx), |
| 123 | "=c" (ecx) |
| 124 | : "1" (PCIBIOS_PCI_BIOS_PRESENT), |
| 125 | "D" (&pci_indirect) |
| 126 | : "memory"); |
| 127 | local_irq_restore(flags); |
| 128 | |
| 129 | status = (eax >> 8) & 0xff; |
| 130 | hw_mech = eax & 0xff; |
| 131 | major_ver = (ebx >> 8) & 0xff; |
| 132 | minor_ver = ebx & 0xff; |
| 133 | if (pcibios_last_bus < 0) |
| 134 | pcibios_last_bus = ecx & 0xff; |
| 135 | DBG("PCI: BIOS probe returned s=%02x hw=%02x ver=%02x.%02x l=%02x\n", |
| 136 | status, hw_mech, major_ver, minor_ver, pcibios_last_bus); |
| 137 | if (status || signature != PCI_SIGNATURE) { |
| 138 | printk (KERN_ERR "PCI: BIOS BUG #%x[%08x] found\n", |
| 139 | status, signature); |
| 140 | return 0; |
| 141 | } |
| 142 | printk(KERN_INFO "PCI: PCI BIOS revision %x.%02x entry at 0x%lx, last bus=%d\n", |
| 143 | major_ver, minor_ver, pcibios_entry, pcibios_last_bus); |
| 144 | #ifdef CONFIG_PCI_DIRECT |
| 145 | if (!(hw_mech & PCIBIOS_HW_TYPE1)) |
| 146 | pci_probe &= ~PCI_PROBE_CONF1; |
| 147 | if (!(hw_mech & PCIBIOS_HW_TYPE2)) |
| 148 | pci_probe &= ~PCI_PROBE_CONF2; |
| 149 | #endif |
| 150 | return 1; |
| 151 | } |
| 152 | return 0; |
| 153 | } |
| 154 | |
| 155 | static int __devinit pci_bios_find_device (unsigned short vendor, unsigned short device_id, |
| 156 | unsigned short index, unsigned char *bus, unsigned char *device_fn) |
| 157 | { |
| 158 | unsigned short bx; |
| 159 | unsigned short ret; |
| 160 | |
| 161 | __asm__("lcall *(%%edi); cld\n\t" |
| 162 | "jc 1f\n\t" |
| 163 | "xor %%ah, %%ah\n" |
| 164 | "1:" |
| 165 | : "=b" (bx), |
| 166 | "=a" (ret) |
| 167 | : "1" (PCIBIOS_FIND_PCI_DEVICE), |
| 168 | "c" (device_id), |
| 169 | "d" (vendor), |
| 170 | "S" ((int) index), |
| 171 | "D" (&pci_indirect)); |
| 172 | *bus = (bx >> 8) & 0xff; |
| 173 | *device_fn = bx & 0xff; |
| 174 | return (int) (ret & 0xff00) >> 8; |
| 175 | } |
| 176 | |
| 177 | static int pci_bios_read(unsigned int seg, unsigned int bus, |
| 178 | unsigned int devfn, int reg, int len, u32 *value) |
| 179 | { |
| 180 | unsigned long result = 0; |
| 181 | unsigned long flags; |
| 182 | unsigned long bx = (bus << 8) | devfn; |
| 183 | |
| 184 | if (!value || (bus > 255) || (devfn > 255) || (reg > 255)) |
| 185 | return -EINVAL; |
| 186 | |
| 187 | spin_lock_irqsave(&pci_config_lock, flags); |
| 188 | |
| 189 | switch (len) { |
| 190 | case 1: |
| 191 | __asm__("lcall *(%%esi); cld\n\t" |
| 192 | "jc 1f\n\t" |
| 193 | "xor %%ah, %%ah\n" |
| 194 | "1:" |
| 195 | : "=c" (*value), |
| 196 | "=a" (result) |
| 197 | : "1" (PCIBIOS_READ_CONFIG_BYTE), |
| 198 | "b" (bx), |
| 199 | "D" ((long)reg), |
| 200 | "S" (&pci_indirect)); |
| 201 | break; |
| 202 | case 2: |
| 203 | __asm__("lcall *(%%esi); cld\n\t" |
| 204 | "jc 1f\n\t" |
| 205 | "xor %%ah, %%ah\n" |
| 206 | "1:" |
| 207 | : "=c" (*value), |
| 208 | "=a" (result) |
| 209 | : "1" (PCIBIOS_READ_CONFIG_WORD), |
| 210 | "b" (bx), |
| 211 | "D" ((long)reg), |
| 212 | "S" (&pci_indirect)); |
| 213 | break; |
| 214 | case 4: |
| 215 | __asm__("lcall *(%%esi); cld\n\t" |
| 216 | "jc 1f\n\t" |
| 217 | "xor %%ah, %%ah\n" |
| 218 | "1:" |
| 219 | : "=c" (*value), |
| 220 | "=a" (result) |
| 221 | : "1" (PCIBIOS_READ_CONFIG_DWORD), |
| 222 | "b" (bx), |
| 223 | "D" ((long)reg), |
| 224 | "S" (&pci_indirect)); |
| 225 | break; |
| 226 | } |
| 227 | |
| 228 | spin_unlock_irqrestore(&pci_config_lock, flags); |
| 229 | |
| 230 | return (int)((result & 0xff00) >> 8); |
| 231 | } |
| 232 | |
| 233 | static int pci_bios_write(unsigned int seg, unsigned int bus, |
| 234 | unsigned int devfn, int reg, int len, u32 value) |
| 235 | { |
| 236 | unsigned long result = 0; |
| 237 | unsigned long flags; |
| 238 | unsigned long bx = (bus << 8) | devfn; |
| 239 | |
| 240 | if ((bus > 255) || (devfn > 255) || (reg > 255)) |
| 241 | return -EINVAL; |
| 242 | |
| 243 | spin_lock_irqsave(&pci_config_lock, flags); |
| 244 | |
| 245 | switch (len) { |
| 246 | case 1: |
| 247 | __asm__("lcall *(%%esi); cld\n\t" |
| 248 | "jc 1f\n\t" |
| 249 | "xor %%ah, %%ah\n" |
| 250 | "1:" |
| 251 | : "=a" (result) |
| 252 | : "0" (PCIBIOS_WRITE_CONFIG_BYTE), |
| 253 | "c" (value), |
| 254 | "b" (bx), |
| 255 | "D" ((long)reg), |
| 256 | "S" (&pci_indirect)); |
| 257 | break; |
| 258 | case 2: |
| 259 | __asm__("lcall *(%%esi); cld\n\t" |
| 260 | "jc 1f\n\t" |
| 261 | "xor %%ah, %%ah\n" |
| 262 | "1:" |
| 263 | : "=a" (result) |
| 264 | : "0" (PCIBIOS_WRITE_CONFIG_WORD), |
| 265 | "c" (value), |
| 266 | "b" (bx), |
| 267 | "D" ((long)reg), |
| 268 | "S" (&pci_indirect)); |
| 269 | break; |
| 270 | case 4: |
| 271 | __asm__("lcall *(%%esi); cld\n\t" |
| 272 | "jc 1f\n\t" |
| 273 | "xor %%ah, %%ah\n" |
| 274 | "1:" |
| 275 | : "=a" (result) |
| 276 | : "0" (PCIBIOS_WRITE_CONFIG_DWORD), |
| 277 | "c" (value), |
| 278 | "b" (bx), |
| 279 | "D" ((long)reg), |
| 280 | "S" (&pci_indirect)); |
| 281 | break; |
| 282 | } |
| 283 | |
| 284 | spin_unlock_irqrestore(&pci_config_lock, flags); |
| 285 | |
| 286 | return (int)((result & 0xff00) >> 8); |
| 287 | } |
| 288 | |
| 289 | |
| 290 | /* |
| 291 | * Function table for BIOS32 access |
| 292 | */ |
| 293 | |
| 294 | static struct pci_raw_ops pci_bios_access = { |
| 295 | .read = pci_bios_read, |
| 296 | .write = pci_bios_write |
| 297 | }; |
| 298 | |
| 299 | /* |
| 300 | * Try to find PCI BIOS. |
| 301 | */ |
| 302 | |
| 303 | static struct pci_raw_ops * __devinit pci_find_bios(void) |
| 304 | { |
| 305 | union bios32 *check; |
| 306 | unsigned char sum; |
| 307 | int i, length; |
| 308 | |
| 309 | /* |
| 310 | * Follow the standard procedure for locating the BIOS32 Service |
| 311 | * directory by scanning the permissible address range from |
| 312 | * 0xe0000 through 0xfffff for a valid BIOS32 structure. |
| 313 | */ |
| 314 | |
| 315 | for (check = (union bios32 *) __va(0xe0000); |
| 316 | check <= (union bios32 *) __va(0xffff0); |
| 317 | ++check) { |
Rusty Russell | bd472c7 | 2006-12-07 02:14:08 +0100 | [diff] [blame] | 318 | long sig; |
| 319 | if (probe_kernel_address(&check->fields.signature, sig)) |
| 320 | continue; |
| 321 | |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 322 | if (check->fields.signature != BIOS32_SIGNATURE) |
| 323 | continue; |
| 324 | length = check->fields.length * 16; |
| 325 | if (!length) |
| 326 | continue; |
| 327 | sum = 0; |
| 328 | for (i = 0; i < length ; ++i) |
| 329 | sum += check->chars[i]; |
| 330 | if (sum != 0) |
| 331 | continue; |
| 332 | if (check->fields.revision != 0) { |
| 333 | printk("PCI: unsupported BIOS32 revision %d at 0x%p\n", |
| 334 | check->fields.revision, check); |
| 335 | continue; |
| 336 | } |
| 337 | DBG("PCI: BIOS32 Service Directory structure at 0x%p\n", check); |
| 338 | if (check->fields.entry >= 0x100000) { |
Rusty Russell | bd472c7 | 2006-12-07 02:14:08 +0100 | [diff] [blame] | 339 | printk("PCI: BIOS32 entry (0x%p) in high memory, " |
| 340 | "cannot use.\n", check); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 341 | return NULL; |
| 342 | } else { |
| 343 | unsigned long bios32_entry = check->fields.entry; |
Rusty Russell | bd472c7 | 2006-12-07 02:14:08 +0100 | [diff] [blame] | 344 | DBG("PCI: BIOS32 Service Directory entry at 0x%lx\n", |
| 345 | bios32_entry); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 346 | bios32_indirect.address = bios32_entry + PAGE_OFFSET; |
| 347 | if (check_pcibios()) |
| 348 | return &pci_bios_access; |
| 349 | } |
| 350 | break; /* Hopefully more than one BIOS32 cannot happen... */ |
| 351 | } |
| 352 | |
| 353 | return NULL; |
| 354 | } |
| 355 | |
| 356 | /* |
| 357 | * Sort the device list according to PCI BIOS. Nasty hack, but since some |
| 358 | * fool forgot to define the `correct' device order in the PCI BIOS specs |
| 359 | * and we want to be (possibly bug-to-bug ;-]) compatible with older kernels |
| 360 | * which used BIOS ordering, we are bound to do this... |
| 361 | */ |
| 362 | |
| 363 | void __devinit pcibios_sort(void) |
| 364 | { |
| 365 | LIST_HEAD(sorted_devices); |
| 366 | struct list_head *ln; |
| 367 | struct pci_dev *dev, *d; |
| 368 | int idx, found; |
| 369 | unsigned char bus, devfn; |
| 370 | |
| 371 | DBG("PCI: Sorting device list...\n"); |
| 372 | while (!list_empty(&pci_devices)) { |
| 373 | ln = pci_devices.next; |
| 374 | dev = pci_dev_g(ln); |
| 375 | idx = found = 0; |
| 376 | while (pci_bios_find_device(dev->vendor, dev->device, idx, &bus, &devfn) == PCIBIOS_SUCCESSFUL) { |
| 377 | idx++; |
| 378 | list_for_each(ln, &pci_devices) { |
| 379 | d = pci_dev_g(ln); |
| 380 | if (d->bus->number == bus && d->devfn == devfn) { |
Akinobu Mita | a7addce | 2006-06-26 00:24:39 -0700 | [diff] [blame] | 381 | list_move_tail(&d->global_list, &sorted_devices); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 382 | if (d == dev) |
| 383 | found = 1; |
| 384 | break; |
| 385 | } |
| 386 | } |
| 387 | if (ln == &pci_devices) { |
| 388 | printk(KERN_WARNING "PCI: BIOS reporting unknown device %02x:%02x\n", bus, devfn); |
| 389 | /* |
| 390 | * We must not continue scanning as several buggy BIOSes |
| 391 | * return garbage after the last device. Grr. |
| 392 | */ |
| 393 | break; |
| 394 | } |
| 395 | } |
| 396 | if (!found) { |
| 397 | printk(KERN_WARNING "PCI: Device %s not found by BIOS\n", |
| 398 | pci_name(dev)); |
Akinobu Mita | a7addce | 2006-06-26 00:24:39 -0700 | [diff] [blame] | 399 | list_move_tail(&dev->global_list, &sorted_devices); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 400 | } |
| 401 | } |
| 402 | list_splice(&sorted_devices, &pci_devices); |
| 403 | } |
| 404 | |
| 405 | /* |
| 406 | * BIOS Functions for IRQ Routing |
| 407 | */ |
| 408 | |
| 409 | struct irq_routing_options { |
| 410 | u16 size; |
| 411 | struct irq_info *table; |
| 412 | u16 segment; |
| 413 | } __attribute__((packed)); |
| 414 | |
| 415 | struct irq_routing_table * __devinit pcibios_get_irq_routing_table(void) |
| 416 | { |
| 417 | struct irq_routing_options opt; |
| 418 | struct irq_routing_table *rt = NULL; |
| 419 | int ret, map; |
| 420 | unsigned long page; |
| 421 | |
| 422 | if (!pci_bios_present) |
| 423 | return NULL; |
| 424 | page = __get_free_page(GFP_KERNEL); |
| 425 | if (!page) |
| 426 | return NULL; |
| 427 | opt.table = (struct irq_info *) page; |
| 428 | opt.size = PAGE_SIZE; |
| 429 | opt.segment = __KERNEL_DS; |
| 430 | |
| 431 | DBG("PCI: Fetching IRQ routing table... "); |
| 432 | __asm__("push %%es\n\t" |
| 433 | "push %%ds\n\t" |
| 434 | "pop %%es\n\t" |
| 435 | "lcall *(%%esi); cld\n\t" |
| 436 | "pop %%es\n\t" |
| 437 | "jc 1f\n\t" |
| 438 | "xor %%ah, %%ah\n" |
| 439 | "1:" |
| 440 | : "=a" (ret), |
| 441 | "=b" (map), |
| 442 | "=m" (opt) |
| 443 | : "0" (PCIBIOS_GET_ROUTING_OPTIONS), |
| 444 | "1" (0), |
| 445 | "D" ((long) &opt), |
| 446 | "S" (&pci_indirect), |
| 447 | "m" (opt) |
| 448 | : "memory"); |
| 449 | DBG("OK ret=%d, size=%d, map=%x\n", ret, opt.size, map); |
| 450 | if (ret & 0xff00) |
| 451 | printk(KERN_ERR "PCI: Error %02x when fetching IRQ routing table.\n", (ret >> 8) & 0xff); |
| 452 | else if (opt.size) { |
| 453 | rt = kmalloc(sizeof(struct irq_routing_table) + opt.size, GFP_KERNEL); |
| 454 | if (rt) { |
| 455 | memset(rt, 0, sizeof(struct irq_routing_table)); |
| 456 | rt->size = opt.size + sizeof(struct irq_routing_table); |
| 457 | rt->exclusive_irqs = map; |
| 458 | memcpy(rt->slots, (void *) page, opt.size); |
| 459 | printk(KERN_INFO "PCI: Using BIOS Interrupt Routing Table\n"); |
| 460 | } |
| 461 | } |
| 462 | free_page(page); |
| 463 | return rt; |
| 464 | } |
Alexey Dobriyan | 129f694 | 2005-06-23 00:08:33 -0700 | [diff] [blame] | 465 | EXPORT_SYMBOL(pcibios_get_irq_routing_table); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 466 | |
| 467 | int pcibios_set_irq_routing(struct pci_dev *dev, int pin, int irq) |
| 468 | { |
| 469 | int ret; |
| 470 | |
| 471 | __asm__("lcall *(%%esi); cld\n\t" |
| 472 | "jc 1f\n\t" |
| 473 | "xor %%ah, %%ah\n" |
| 474 | "1:" |
| 475 | : "=a" (ret) |
| 476 | : "0" (PCIBIOS_SET_PCI_HW_INT), |
| 477 | "b" ((dev->bus->number << 8) | dev->devfn), |
| 478 | "c" ((irq << 8) | (pin + 10)), |
| 479 | "S" (&pci_indirect)); |
| 480 | return !(ret & 0xff00); |
| 481 | } |
Alexey Dobriyan | 129f694 | 2005-06-23 00:08:33 -0700 | [diff] [blame] | 482 | EXPORT_SYMBOL(pcibios_set_irq_routing); |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 483 | |
Andi Kleen | 92c05fc | 2006-03-23 14:35:12 -0800 | [diff] [blame] | 484 | void __init pci_pcbios_init(void) |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 485 | { |
| 486 | if ((pci_probe & PCI_PROBE_BIOS) |
| 487 | && ((raw_pci_ops = pci_find_bios()))) { |
| 488 | pci_probe |= PCI_BIOS_SORT; |
| 489 | pci_bios_present = 1; |
| 490 | } |
Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 491 | } |
| 492 | |