arch/x86/pci/mmconfig-shared.c

   1 /*
   2  * mmconfig-shared.c - Low-level direct PCI config space access via
   3  *                     MMCONFIG - common code between i386 and x86-64.
   4  *
   5  * This code does:
   6  * - known chipset handling
   7  * - ACPI decoding and validation
   8  *
   9  * Per-architecture code takes care of the mappings and accesses
  10  * themselves.
  11  */
  12
  13 #include <linux/pci.h>
  14 #include <linux/init.h>
  15 #include <linux/acpi.h>
  16 #include <linux/bitmap.h>
  17 #include <asm/e820.h>
  18
  19 #include "pci.h"
  20
  21 /* aperture is up to 256MB but BIOS may reserve less */
  22 #define MMCONFIG_APER_MIN       (2 * 1024*1024)
  23 #define MMCONFIG_APER_MAX       (256 * 1024*1024)
  24
  25 /* Indicate if the mmcfg resources have been placed into the resource table. */
  26 static int __initdata pci_mmcfg_resources_inserted;
  27
  28 static const char __init *pci_mmcfg_e7520(void)
  29 {
  30         u32 win;
  31         raw_pci_ops->read(0, 0, PCI_DEVFN(0, 0), 0xce, 2, &win);
  32
  33         win = win & 0xf000;
  34         if(win == 0x0000 || win == 0xf000)
  35                 pci_mmcfg_config_num = 0;
  36         else {
  37                 pci_mmcfg_config_num = 1;
  38                 pci_mmcfg_config = kzalloc(sizeof(pci_mmcfg_config[0]), GFP_KERNEL);
  39                 if (!pci_mmcfg_config)
  40                         return NULL;
  41                 pci_mmcfg_config[0].address = win << 16;
  42                 pci_mmcfg_config[0].pci_segment = 0;
  43                 pci_mmcfg_config[0].start_bus_number = 0;
  44                 pci_mmcfg_config[0].end_bus_number = 255;
  45         }
  46
  47         return "Intel Corporation E7520 Memory Controller Hub";
  48 }
  49
  50 static const char __init *pci_mmcfg_intel_945(void)
  51 {
  52         u32 pciexbar, mask = 0, len = 0;
  53
  54         pci_mmcfg_config_num = 1;
  55
  56         raw_pci_ops->read(0, 0, PCI_DEVFN(0, 0), 0x48, 4, &pciexbar);
  57
  58         /* Enable bit */
  59         if (!(pciexbar & 1))
  60                 pci_mmcfg_config_num = 0;
  61
  62         /* Size bits */
  63         switch ((pciexbar >> 1) & 3) {
  64         case 0:
  65                 mask = 0xf0000000U;
  66                 len  = 0x10000000U;
  67                 break;
  68         case 1:
  69                 mask = 0xf8000000U;
  70                 len  = 0x08000000U;
  71                 break;
  72         case 2:
  73                 mask = 0xfc000000U;
  74                 len  = 0x04000000U;
  75                 break;
  76         default:
  77                 pci_mmcfg_config_num = 0;
  78         }
  79
  80         /* Errata #2, things break when not aligned on a 256Mb boundary */
  81         /* Can only happen in 64M/128M mode */
  82
  83         if ((pciexbar & mask) & 0x0fffffffU)
  84                 pci_mmcfg_config_num = 0;
  85
  86         /* Don't hit the APIC registers and their friends */
  87         if ((pciexbar & mask) >= 0xf0000000U)
  88                 pci_mmcfg_config_num = 0;
  89
  90         if (pci_mmcfg_config_num) {
  91                 pci_mmcfg_config = kzalloc(sizeof(pci_mmcfg_config[0]), GFP_KERNEL);
  92                 if (!pci_mmcfg_config)
  93                         return NULL;
  94                 pci_mmcfg_config[0].address = pciexbar & mask;
  95                 pci_mmcfg_config[0].pci_segment = 0;
  96                 pci_mmcfg_config[0].start_bus_number = 0;
  97                 pci_mmcfg_config[0].end_bus_number = (len >> 20) - 1;
  98         }
  99
 100         return "Intel Corporation 945G/GZ/P/PL Express Memory Controller Hub";
 101 }
 102
 103 static const char __init *pci_mmcfg_amd_fam10h(void)
 104 {
 105         u32 low, high, address;
 106         u64 base, msr;
 107         int i;
 108         unsigned segnbits = 0, busnbits;
 109
 110         if (!(pci_probe & PCI_CHECK_ENABLE_AMD_MMCONF))
 111                 return NULL;
 112
 113         address = MSR_FAM10H_MMIO_CONF_BASE;
 114         if (rdmsr_safe(address, &low, &high))
 115                 return NULL;
 116
 117         msr = high;
 118         msr <<= 32;
 119         msr |= low;
 120
 121         /* mmconfig is not enable */
 122         if (!(msr & FAM10H_MMIO_CONF_ENABLE))
 123                 return NULL;
 124
 125         base = msr & (FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT);
 126
 127         busnbits = (msr >> FAM10H_MMIO_CONF_BUSRANGE_SHIFT) &
 128                          FAM10H_MMIO_CONF_BUSRANGE_MASK;
 129
 130         /*
 131          * only handle bus 0 ?
 132          * need to skip it
 133          */
 134         if (!busnbits)
 135                 return NULL;
 136
 137         if (busnbits > 8) {
 138                 segnbits = busnbits - 8;
 139                 busnbits = 8;
 140         }
 141
 142         pci_mmcfg_config_num = (1 << segnbits);
 143         pci_mmcfg_config = kzalloc(sizeof(pci_mmcfg_config[0]) *
 144                                    pci_mmcfg_config_num, GFP_KERNEL);
 145         if (!pci_mmcfg_config)
 146                 return NULL;
 147
 148         for (i = 0; i < (1 << segnbits); i++) {
 149                 pci_mmcfg_config[i].address = base + (1<<28) * i;
 150                 pci_mmcfg_config[i].pci_segment = i;
 151                 pci_mmcfg_config[i].start_bus_number = 0;
 152                 pci_mmcfg_config[i].end_bus_number = (1 << busnbits) - 1;
 153         }
 154
 155         return "AMD Family 10h NB";
 156 }
 157
 158 struct pci_mmcfg_hostbridge_probe {
 159         u32 bus;
 160         u32 devfn;
 161         u32 vendor;
 162         u32 device;
 163         const char *(*probe)(void);
 164 };
 165
 166 static struct pci_mmcfg_hostbridge_probe pci_mmcfg_probes[] __initdata = {
 167         { 0, PCI_DEVFN(0, 0), PCI_VENDOR_ID_INTEL,
 168           PCI_DEVICE_ID_INTEL_E7520_MCH, pci_mmcfg_e7520 },
 169         { 0, PCI_DEVFN(0, 0), PCI_VENDOR_ID_INTEL,
 170           PCI_DEVICE_ID_INTEL_82945G_HB, pci_mmcfg_intel_945 },
 171         { 0, PCI_DEVFN(0x18, 0), PCI_VENDOR_ID_AMD,
 172           0x1200, pci_mmcfg_amd_fam10h },
 173         { 0xff, PCI_DEVFN(0, 0), PCI_VENDOR_ID_AMD,
 174           0x1200, pci_mmcfg_amd_fam10h },
 175 };
 176
 177 static int __init pci_mmcfg_check_hostbridge(void)
 178 {
 179         u32 l;
 180         u32 bus, devfn;
 181         u16 vendor, device;
 182         int i;
 183         const char *name;
 184
 185         if (!raw_pci_ops)
 186                 return 0;
 187
 188         pci_mmcfg_config_num = 0;
 189         pci_mmcfg_config = NULL;
 190         name = NULL;
 191
 192         for (i = 0; !name && i < ARRAY_SIZE(pci_mmcfg_probes); i++) {
 193                 bus =  pci_mmcfg_probes[i].bus;
 194                 devfn = pci_mmcfg_probes[i].devfn;
 195                 raw_pci_ops->read(0, bus, devfn, 0, 4, &l);
 196                 vendor = l & 0xffff;
 197                 device = (l >> 16) & 0xffff;
 198
 199                 if (pci_mmcfg_probes[i].vendor == vendor &&
 200                     pci_mmcfg_probes[i].device == device)
 201                         name = pci_mmcfg_probes[i].probe();
 202         }
 203
 204         if (name) {
 205                 printk(KERN_INFO "PCI: Found %s %s MMCONFIG support.\n",
 206                        name, pci_mmcfg_config_num ? "with" : "without");
 207         }
 208
 209         return name != NULL;
 210 }
 211
 212 static void __init pci_mmcfg_insert_resources(unsigned long resource_flags)
 213 {
 214 #define PCI_MMCFG_RESOURCE_NAME_LEN 19
 215         int i;
 216         struct resource *res;
 217         char *names;
 218         unsigned num_buses;
 219
 220         res = kcalloc(PCI_MMCFG_RESOURCE_NAME_LEN + sizeof(*res),
 221                         pci_mmcfg_config_num, GFP_KERNEL);
 222         if (!res) {
 223                 printk(KERN_ERR "PCI: Unable to allocate MMCONFIG resources\n");
 224                 return;
 225         }
 226
 227         names = (void *)&res[pci_mmcfg_config_num];
 228         for (i = 0; i < pci_mmcfg_config_num; i++, res++) {
 229                 struct acpi_mcfg_allocation *cfg = &pci_mmcfg_config[i];
 230                 num_buses = cfg->end_bus_number - cfg->start_bus_number + 1;
 231                 res->name = names;
 232                 snprintf(names, PCI_MMCFG_RESOURCE_NAME_LEN, "PCI MMCONFIG %u",
 233                          cfg->pci_segment);
 234                 res->start = cfg->address;
 235                 res->end = res->start + (num_buses << 20) - 1;
 236                 res->flags = IORESOURCE_MEM | resource_flags;
 237                 insert_resource(&iomem_resource, res);
 238                 names += PCI_MMCFG_RESOURCE_NAME_LEN;
 239         }
 240
 241         /* Mark that the resources have been inserted. */
 242         pci_mmcfg_resources_inserted = 1;
 243 }
 244
 245 static acpi_status __init check_mcfg_resource(struct acpi_resource *res,
 246                                               void *data)
 247 {
 248         struct resource *mcfg_res = data;
 249         struct acpi_resource_address64 address;
 250         acpi_status status;
 251
 252         if (res->type == ACPI_RESOURCE_TYPE_FIXED_MEMORY32) {
 253                 struct acpi_resource_fixed_memory32 *fixmem32 =
 254                         &res->data.fixed_memory32;
 255                 if (!fixmem32)
 256                         return AE_OK;
 257                 if ((mcfg_res->start >= fixmem32->address) &&
 258                     (mcfg_res->end < (fixmem32->address +
 259                                       fixmem32->address_length))) {
 260                         mcfg_res->flags = 1;
 261                         return AE_CTRL_TERMINATE;
 262                 }
 263         }
 264         if ((res->type != ACPI_RESOURCE_TYPE_ADDRESS32) &&
 265             (res->type != ACPI_RESOURCE_TYPE_ADDRESS64))
 266                 return AE_OK;
 267
 268         status = acpi_resource_to_address64(res, &address);
 269         if (ACPI_FAILURE(status) ||
 270            (address.address_length <= 0) ||
 271            (address.resource_type != ACPI_MEMORY_RANGE))
 272                 return AE_OK;
 273
 274         if ((mcfg_res->start >= address.minimum) &&
 275             (mcfg_res->end < (address.minimum + address.address_length))) {
 276                 mcfg_res->flags = 1;
 277                 return AE_CTRL_TERMINATE;
 278         }
 279         return AE_OK;
 280 }
 281
 282 static acpi_status __init find_mboard_resource(acpi_handle handle, u32 lvl,
 283                 void *context, void **rv)
 284 {
 285         struct resource *mcfg_res = context;
 286
 287         acpi_walk_resources(handle, METHOD_NAME__CRS,
 288                             check_mcfg_resource, context);
 289
 290         if (mcfg_res->flags)
 291                 return AE_CTRL_TERMINATE;
 292
 293         return AE_OK;
 294 }
 295
 296 static int __init is_acpi_reserved(unsigned long start, unsigned long end)
 297 {
 298         struct resource mcfg_res;
 299
 300         mcfg_res.start = start;
 301         mcfg_res.end = end;
 302         mcfg_res.flags = 0;
 303
 304         acpi_get_devices("PNP0C01", find_mboard_resource, &mcfg_res, NULL);
 305
 306         if (!mcfg_res.flags)
 307                 acpi_get_devices("PNP0C02", find_mboard_resource, &mcfg_res,
 308                                  NULL);
 309
 310         return mcfg_res.flags;
 311 }
 312
 313 static void __init pci_mmcfg_reject_broken(int early)
 314 {
 315         typeof(pci_mmcfg_config[0]) *cfg;
 316         int i;
 317
 318         if ((pci_mmcfg_config_num == 0) ||
 319             (pci_mmcfg_config == NULL) ||
 320             (pci_mmcfg_config[0].address == 0))
 321                 return;
 322
 323         cfg = &pci_mmcfg_config[0];
 324
 325         for (i = 0; i < pci_mmcfg_config_num; i++) {
 326                 int valid = 0;
 327                 u32 size = (cfg->end_bus_number + 1) << 20;
 328                 cfg = &pci_mmcfg_config[i];
 329                 printk(KERN_NOTICE "PCI: MCFG configuration %d: base %lx "
 330                        "segment %hu buses %u - %u\n",
 331                        i, (unsigned long)cfg->address, cfg->pci_segment,
 332                        (unsigned int)cfg->start_bus_number,
 333                        (unsigned int)cfg->end_bus_number);
 334
 335                 if (!early &&
 336                     is_acpi_reserved(cfg->address, cfg->address + size - 1)) {
 337                         printk(KERN_NOTICE "PCI: MCFG area at %Lx reserved "
 338                                "in ACPI motherboard resources\n",
 339                                cfg->address);
 340                         valid = 1;
 341                 }
 342
 343                 if (valid)
 344                         continue;
 345
 346                 if (!early)
 347                         printk(KERN_ERR "PCI: BIOS Bug: MCFG area at %Lx is not"
 348                                " reserved in ACPI motherboard resources\n",
 349                                cfg->address);
 350                 /* Don't try to do this check unless configuration
 351                    type 1 is available. how about type 2 ?*/
 352                 if (raw_pci_ops && e820_all_mapped(cfg->address,
 353                                                   cfg->address + size - 1,
 354                                                   E820_RESERVED)) {
 355                         printk(KERN_NOTICE
 356                                "PCI: MCFG area at %Lx reserved in E820\n",
 357                                cfg->address);
 358                         valid = 1;
 359                 }
 360
 361                 if (!valid)
 362                         goto reject;
 363         }
 364
 365         return;
 366
 367 reject:
 368         printk(KERN_INFO "PCI: Not using MMCONFIG.\n");
 369         pci_mmcfg_arch_free();
 370         kfree(pci_mmcfg_config);
 371         pci_mmcfg_config = NULL;
 372         pci_mmcfg_config_num = 0;
 373 }
 374
 375 static int __initdata known_bridge;
 376
 377 static void __init __pci_mmcfg_init(int early)
 378 {
 379         /* MMCONFIG disabled */
 380         if ((pci_probe & PCI_PROBE_MMCONF) == 0)
 381                 return;
 382
 383         /* MMCONFIG already enabled */
 384         if (!early && !(pci_probe & PCI_PROBE_MASK & ~PCI_PROBE_MMCONF))
 385                 return;
 386
 387         /* for late to exit */
 388         if (known_bridge)
 389                 return;
 390
 391         if (early) {
 392                 if (pci_mmcfg_check_hostbridge())
 393                         known_bridge = 1;
 394         }
 395
 396         if (!known_bridge) {
 397                 acpi_table_parse(ACPI_SIG_MCFG, acpi_parse_mcfg);
 398                 pci_mmcfg_reject_broken(early);
 399         }
 400
 401         if ((pci_mmcfg_config_num == 0) ||
 402             (pci_mmcfg_config == NULL) ||
 403             (pci_mmcfg_config[0].address == 0))
 404                 return;
 405
 406         if (pci_mmcfg_arch_init()) {
 407                 if (known_bridge)
 408                         pci_mmcfg_insert_resources(IORESOURCE_BUSY);
 409                 pci_probe = (pci_probe & ~PCI_PROBE_MASK) | PCI_PROBE_MMCONF;
 410         } else {
 411                 /*
 412                  * Signal not to attempt to insert mmcfg resources because
 413                  * the architecture mmcfg setup could not initialize.
 414                  */
 415                 pci_mmcfg_resources_inserted = 1;
 416         }
 417 }
 418
 419 void __init pci_mmcfg_early_init(void)
 420 {
 421         __pci_mmcfg_init(1);
 422 }
 423
 424 void __init pci_mmcfg_late_init(void)
 425 {
 426         __pci_mmcfg_init(0);
 427 }
 428
 429 static int __init pci_mmcfg_late_insert_resources(void)
 430 {
 431         /*
 432          * If resources are already inserted or we are not using MMCONFIG,
 433          * don't insert the resources.
 434          */
 435         if ((pci_mmcfg_resources_inserted == 1) ||
 436             (pci_probe & PCI_PROBE_MMCONF) == 0 ||
 437             (pci_mmcfg_config_num == 0) ||
 438             (pci_mmcfg_config == NULL) ||
 439             (pci_mmcfg_config[0].address == 0))
 440                 return 1;
 441
 442         /*
 443          * Attempt to insert the mmcfg resources but not with the busy flag
 444          * marked so it won't cause request errors when __request_region is
 445          * called.
 446          */
 447         pci_mmcfg_insert_resources(0);
 448
 449         return 0;
 450 }
 451
 452 /*
 453  * Perform MMCONFIG resource insertion after PCI initialization to allow for
 454  * misprogrammed MCFG tables that state larger sizes but actually conflict
 455  * with other system resources.
 456  */
 457 late_initcall(pci_mmcfg_late_insert_resources);