arch/x86/kernel/mpparse.c

   1 /*
   2  *      Intel Multiprocessor Specification 1.1 and 1.4
   3  *      compliant MP-table parsing routines.
   4  *
   5  *      (c) 1995 Alan Cox, Building #3 <alan@lxorguk.ukuu.org.uk>
   6  *      (c) 1998, 1999, 2000, 2009 Ingo Molnar <mingo@redhat.com>
   7  *      (c) 2008 Alexey Starikovskiy <astarikovskiy@suse.de>
   8  */
   9
  10 #include <linux/mm.h>
  11 #include <linux/init.h>
  12 #include <linux/delay.h>
  13 #include <linux/bootmem.h>
  14 #include <linux/memblock.h>
  15 #include <linux/kernel_stat.h>
  16 #include <linux/mc146818rtc.h>
  17 #include <linux/bitops.h>
  18 #include <linux/acpi.h>
  19 #include <linux/module.h>
  20 #include <linux/smp.h>
  21 #include <linux/pci.h>
  22
  23 #include <asm/mtrr.h>
  24 #include <asm/mpspec.h>
  25 #include <asm/pgalloc.h>
  26 #include <asm/io_apic.h>
  27 #include <asm/proto.h>
  28 #include <asm/bios_ebda.h>
  29 #include <asm/e820.h>
  30 #include <asm/trampoline.h>
  31 #include <asm/setup.h>
  32 #include <asm/smp.h>
  33
  34 #include <asm/apic.h>
  35 /*
  36  * Checksum an MP configuration block.
  37  */
  38
  39 static int __init mpf_checksum(unsigned char *mp, int len)
  40 {
  41         int sum = 0;
  42
  43         while (len--)
  44                 sum += *mp++;
  45
  46         return sum & 0xFF;
  47 }
  48
  49 int __init default_mpc_apic_id(struct mpc_cpu *m)
  50 {
  51         return m->apicid;
  52 }
  53
  54 static void __init MP_processor_info(struct mpc_cpu *m)
  55 {
  56         int apicid;
  57         char *bootup_cpu = "";
  58
  59         if (!(m->cpuflag & CPU_ENABLED)) {
  60                 disabled_cpus++;
  61                 return;
  62         }
  63
  64         apicid = x86_init.mpparse.mpc_apic_id(m);
  65
  66         if (m->cpuflag & CPU_BOOTPROCESSOR) {
  67                 bootup_cpu = " (Bootup-CPU)";
  68                 boot_cpu_physical_apicid = m->apicid;
  69         }
  70
  71         printk(KERN_INFO "Processor #%d%s\n", m->apicid, bootup_cpu);
  72         generic_processor_info(apicid, m->apicver);
  73 }
  74
  75 #ifdef CONFIG_X86_IO_APIC
  76 void __init default_mpc_oem_bus_info(struct mpc_bus *m, char *str)
  77 {
  78         memcpy(str, m->bustype, 6);
  79         str[6] = 0;
  80         apic_printk(APIC_VERBOSE, "Bus #%d is %s\n", m->busid, str);
  81 }
  82
  83 static void __init MP_bus_info(struct mpc_bus *m)
  84 {
  85         char str[7];
  86
  87         x86_init.mpparse.mpc_oem_bus_info(m, str);
  88
  89 #if MAX_MP_BUSSES < 256
  90         if (m->busid >= MAX_MP_BUSSES) {
  91                 printk(KERN_WARNING "MP table busid value (%d) for bustype %s "
  92                        " is too large, max. supported is %d\n",
  93                        m->busid, str, MAX_MP_BUSSES - 1);
  94                 return;
  95         }
  96 #endif
  97
  98         if (strncmp(str, BUSTYPE_ISA, sizeof(BUSTYPE_ISA) - 1) == 0) {
  99                 set_bit(m->busid, mp_bus_not_pci);
 100 #if defined(CONFIG_EISA) || defined(CONFIG_MCA)
 101                 mp_bus_id_to_type[m->busid] = MP_BUS_ISA;
 102 #endif
 103         } else if (strncmp(str, BUSTYPE_PCI, sizeof(BUSTYPE_PCI) - 1) == 0) {
 104                 if (x86_init.mpparse.mpc_oem_pci_bus)
 105                         x86_init.mpparse.mpc_oem_pci_bus(m);
 106
 107                 clear_bit(m->busid, mp_bus_not_pci);
 108 #if defined(CONFIG_EISA) || defined(CONFIG_MCA)
 109                 mp_bus_id_to_type[m->busid] = MP_BUS_PCI;
 110         } else if (strncmp(str, BUSTYPE_EISA, sizeof(BUSTYPE_EISA) - 1) == 0) {
 111                 mp_bus_id_to_type[m->busid] = MP_BUS_EISA;
 112         } else if (strncmp(str, BUSTYPE_MCA, sizeof(BUSTYPE_MCA) - 1) == 0) {
 113                 mp_bus_id_to_type[m->busid] = MP_BUS_MCA;
 114 #endif
 115         } else
 116                 printk(KERN_WARNING "Unknown bustype %s - ignoring\n", str);
 117 }
 118
 119 static void __init MP_ioapic_info(struct mpc_ioapic *m)
 120 {
 121         if (m->flags & MPC_APIC_USABLE)
 122                 mp_register_ioapic(m->apicid, m->apicaddr, gsi_top);
 123 }
 124
 125 static void __init print_mp_irq_info(struct mpc_intsrc *mp_irq)
 126 {
 127         apic_printk(APIC_VERBOSE, "Int: type %d, pol %d, trig %d, bus %02x,"
 128                 " IRQ %02x, APIC ID %x, APIC INT %02x\n",
 129                 mp_irq->irqtype, mp_irq->irqflag & 3,
 130                 (mp_irq->irqflag >> 2) & 3, mp_irq->srcbus,
 131                 mp_irq->srcbusirq, mp_irq->dstapic, mp_irq->dstirq);
 132 }
 133
 134 #else /* CONFIG_X86_IO_APIC */
 135 static inline void __init MP_bus_info(struct mpc_bus *m) {}
 136 static inline void __init MP_ioapic_info(struct mpc_ioapic *m) {}
 137 #endif /* CONFIG_X86_IO_APIC */
 138
 139 static void __init MP_lintsrc_info(struct mpc_lintsrc *m)
 140 {
 141         apic_printk(APIC_VERBOSE, "Lint: type %d, pol %d, trig %d, bus %02x,"
 142                 " IRQ %02x, APIC ID %x, APIC LINT %02x\n",
 143                 m->irqtype, m->irqflag & 3, (m->irqflag >> 2) & 3, m->srcbusid,
 144                 m->srcbusirq, m->destapic, m->destapiclint);
 145 }
 146
 147 /*
 148  * Read/parse the MPC
 149  */
 150 static int __init smp_check_mpc(struct mpc_table *mpc, char *oem, char *str)
 151 {
 152
 153         if (memcmp(mpc->signature, MPC_SIGNATURE, 4)) {
 154                 printk(KERN_ERR "MPTABLE: bad signature [%c%c%c%c]!\n",
 155                        mpc->signature[0], mpc->signature[1],
 156                        mpc->signature[2], mpc->signature[3]);
 157                 return 0;
 158         }
 159         if (mpf_checksum((unsigned char *)mpc, mpc->length)) {
 160                 printk(KERN_ERR "MPTABLE: checksum error!\n");
 161                 return 0;
 162         }
 163         if (mpc->spec != 0x01 && mpc->spec != 0x04) {
 164                 printk(KERN_ERR "MPTABLE: bad table version (%d)!!\n",
 165                        mpc->spec);
 166                 return 0;
 167         }
 168         if (!mpc->lapic) {
 169                 printk(KERN_ERR "MPTABLE: null local APIC address!\n");
 170                 return 0;
 171         }
 172         memcpy(oem, mpc->oem, 8);
 173         oem[8] = 0;
 174         printk(KERN_INFO "MPTABLE: OEM ID: %s\n", oem);
 175
 176         memcpy(str, mpc->productid, 12);
 177         str[12] = 0;
 178
 179         printk(KERN_INFO "MPTABLE: Product ID: %s\n", str);
 180
 181         printk(KERN_INFO "MPTABLE: APIC at: 0x%X\n", mpc->lapic);
 182
 183         return 1;
 184 }
 185
 186 static void skip_entry(unsigned char **ptr, int *count, int size)
 187 {
 188         *ptr += size;
 189         *count += size;
 190 }
 191
 192 static void __init smp_dump_mptable(struct mpc_table *mpc, unsigned char *mpt)
 193 {
 194         printk(KERN_ERR "Your mptable is wrong, contact your HW vendor!\n"
 195                 "type %x\n", *mpt);
 196         print_hex_dump(KERN_ERR, "  ", DUMP_PREFIX_ADDRESS, 16,
 197                         1, mpc, mpc->length, 1);
 198 }
 199
 200 void __init default_smp_read_mpc_oem(struct mpc_table *mpc) { }
 201
 202 static int __init smp_read_mpc(struct mpc_table *mpc, unsigned early)
 203 {
 204         char str[16];
 205         char oem[10];
 206
 207         int count = sizeof(*mpc);
 208         unsigned char *mpt = ((unsigned char *)mpc) + count;
 209
 210         if (!smp_check_mpc(mpc, oem, str))
 211                 return 0;
 212
 213 #ifdef CONFIG_X86_32
 214         generic_mps_oem_check(mpc, oem, str);
 215 #endif
 216         /* Initialize the lapic mapping */
 217         if (!acpi_lapic)
 218                 register_lapic_address(mpc->lapic);
 219
 220         if (early)
 221                 return 1;
 222
 223         if (mpc->oemptr)
 224                 x86_init.mpparse.smp_read_mpc_oem(mpc);
 225
 226         /*
 227          *      Now process the configuration blocks.
 228          */
 229         x86_init.mpparse.mpc_record(0);
 230
 231         while (count < mpc->length) {
 232                 switch (*mpt) {
 233                 case MP_PROCESSOR:
 234                         /* ACPI may have already provided this data */
 235                         if (!acpi_lapic)
 236                                 MP_processor_info((struct mpc_cpu *)mpt);
 237                         skip_entry(&mpt, &count, sizeof(struct mpc_cpu));
 238                         break;
 239                 case MP_BUS:
 240                         MP_bus_info((struct mpc_bus *)mpt);
 241                         skip_entry(&mpt, &count, sizeof(struct mpc_bus));
 242                         break;
 243                 case MP_IOAPIC:
 244                         MP_ioapic_info((struct mpc_ioapic *)mpt);
 245                         skip_entry(&mpt, &count, sizeof(struct mpc_ioapic));
 246                         break;
 247                 case MP_INTSRC:
 248                         mp_save_irq((struct mpc_intsrc *)mpt);
 249                         skip_entry(&mpt, &count, sizeof(struct mpc_intsrc));
 250                         break;
 251                 case MP_LINTSRC:
 252                         MP_lintsrc_info((struct mpc_lintsrc *)mpt);
 253                         skip_entry(&mpt, &count, sizeof(struct mpc_lintsrc));
 254                         break;
 255                 default:
 256                         /* wrong mptable */
 257                         smp_dump_mptable(mpc, mpt);
 258                         count = mpc->length;
 259                         break;
 260                 }
 261                 x86_init.mpparse.mpc_record(1);
 262         }
 263
 264         if (!num_processors)
 265                 printk(KERN_ERR "MPTABLE: no processors registered!\n");
 266         return num_processors;
 267 }
 268
 269 #ifdef CONFIG_X86_IO_APIC
 270
 271 static int __init ELCR_trigger(unsigned int irq)
 272 {
 273         unsigned int port;
 274
 275         port = 0x4d0 + (irq >> 3);
 276         return (inb(port) >> (irq & 7)) & 1;
 277 }
 278
 279 static void __init construct_default_ioirq_mptable(int mpc_default_type)
 280 {
 281         struct mpc_intsrc intsrc;
 282         int i;
 283         int ELCR_fallback = 0;
 284
 285         intsrc.type = MP_INTSRC;
 286         intsrc.irqflag = 0;     /* conforming */
 287         intsrc.srcbus = 0;
 288         intsrc.dstapic = mpc_ioapic_id(0);
 289
 290         intsrc.irqtype = mp_INT;
 291
 292         /*
 293          *  If true, we have an ISA/PCI system with no IRQ entries
 294          *  in the MP table. To prevent the PCI interrupts from being set up
 295          *  incorrectly, we try to use the ELCR. The sanity check to see if
 296          *  there is good ELCR data is very simple - IRQ0, 1, 2 and 13 can
 297          *  never be level sensitive, so we simply see if the ELCR agrees.
 298          *  If it does, we assume it's valid.
 299          */
 300         if (mpc_default_type == 5) {
 301                 printk(KERN_INFO "ISA/PCI bus type with no IRQ information... "
 302                        "falling back to ELCR\n");
 303
 304                 if (ELCR_trigger(0) || ELCR_trigger(1) || ELCR_trigger(2) ||
 305                     ELCR_trigger(13))
 306                         printk(KERN_ERR "ELCR contains invalid data... "
 307                                "not using ELCR\n");
 308                 else {
 309                         printk(KERN_INFO
 310                                "Using ELCR to identify PCI interrupts\n");
 311                         ELCR_fallback = 1;
 312                 }
 313         }
 314
 315         for (i = 0; i < 16; i++) {
 316                 switch (mpc_default_type) {
 317                 case 2:
 318                         if (i == 0 || i == 13)
 319                                 continue;       /* IRQ0 & IRQ13 not connected */
 320                         /* fall through */
 321                 default:
 322                         if (i == 2)
 323                                 continue;       /* IRQ2 is never connected */
 324                 }
 325
 326                 if (ELCR_fallback) {
 327                         /*
 328                          *  If the ELCR indicates a level-sensitive interrupt, we
 329                          *  copy that information over to the MP table in the
 330                          *  irqflag field (level sensitive, active high polarity).
 331                          */
 332                         if (ELCR_trigger(i))
 333                                 intsrc.irqflag = 13;
 334                         else
 335                                 intsrc.irqflag = 0;
 336                 }
 337
 338                 intsrc.srcbusirq = i;
 339                 intsrc.dstirq = i ? i : 2;      /* IRQ0 to INTIN2 */
 340                 mp_save_irq(&intsrc);
 341         }
 342
 343         intsrc.irqtype = mp_ExtINT;
 344         intsrc.srcbusirq = 0;
 345         intsrc.dstirq = 0;      /* 8259A to INTIN0 */
 346         mp_save_irq(&intsrc);
 347 }
 348
 349
 350 static void __init construct_ioapic_table(int mpc_default_type)
 351 {
 352         struct mpc_ioapic ioapic;
 353         struct mpc_bus bus;
 354
 355         bus.type = MP_BUS;
 356         bus.busid = 0;
 357         switch (mpc_default_type) {
 358         default:
 359                 printk(KERN_ERR "???\nUnknown standard configuration %d\n",
 360                        mpc_default_type);
 361                 /* fall through */
 362         case 1:
 363         case 5:
 364                 memcpy(bus.bustype, "ISA   ", 6);
 365                 break;
 366         case 2:
 367         case 6:
 368         case 3:
 369                 memcpy(bus.bustype, "EISA  ", 6);
 370                 break;
 371         case 4:
 372         case 7:
 373                 memcpy(bus.bustype, "MCA   ", 6);
 374         }
 375         MP_bus_info(&bus);
 376         if (mpc_default_type > 4) {
 377                 bus.busid = 1;
 378                 memcpy(bus.bustype, "PCI   ", 6);
 379                 MP_bus_info(&bus);
 380         }
 381
 382         ioapic.type     = MP_IOAPIC;
 383         ioapic.apicid   = 2;
 384         ioapic.apicver  = mpc_default_type > 4 ? 0x10 : 0x01;
 385         ioapic.flags    = MPC_APIC_USABLE;
 386         ioapic.apicaddr = IO_APIC_DEFAULT_PHYS_BASE;
 387         MP_ioapic_info(&ioapic);
 388
 389         /*
 390          * We set up most of the low 16 IO-APIC pins according to MPS rules.
 391          */
 392         construct_default_ioirq_mptable(mpc_default_type);
 393 }
 394 #else
 395 static inline void __init construct_ioapic_table(int mpc_default_type) { }
 396 #endif
 397
 398 static inline void __init construct_default_ISA_mptable(int mpc_default_type)
 399 {
 400         struct mpc_cpu processor;
 401         struct mpc_lintsrc lintsrc;
 402         int linttypes[2] = { mp_ExtINT, mp_NMI };
 403         int i;
 404
 405         /*
 406          * local APIC has default address
 407          */
 408         mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
 409
 410         /*
 411          * 2 CPUs, numbered 0 & 1.
 412          */
 413         processor.type = MP_PROCESSOR;
 414         /* Either an integrated APIC or a discrete 82489DX. */
 415         processor.apicver = mpc_default_type > 4 ? 0x10 : 0x01;
 416         processor.cpuflag = CPU_ENABLED;
 417         processor.cpufeature = (boot_cpu_data.x86 << 8) |
 418             (boot_cpu_data.x86_model << 4) | boot_cpu_data.x86_mask;
 419         processor.featureflag = boot_cpu_data.x86_capability[0];
 420         processor.reserved[0] = 0;
 421         processor.reserved[1] = 0;
 422         for (i = 0; i < 2; i++) {
 423                 processor.apicid = i;
 424                 MP_processor_info(&processor);
 425         }
 426
 427         construct_ioapic_table(mpc_default_type);
 428
 429         lintsrc.type = MP_LINTSRC;
 430         lintsrc.irqflag = 0;            /* conforming */
 431         lintsrc.srcbusid = 0;
 432         lintsrc.srcbusirq = 0;
 433         lintsrc.destapic = MP_APIC_ALL;
 434         for (i = 0; i < 2; i++) {
 435                 lintsrc.irqtype = linttypes[i];
 436                 lintsrc.destapiclint = i;
 437                 MP_lintsrc_info(&lintsrc);
 438         }
 439 }
 440
 441 static struct mpf_intel *mpf_found;
 442
 443 static unsigned long __init get_mpc_size(unsigned long physptr)
 444 {
 445         struct mpc_table *mpc;
 446         unsigned long size;
 447
 448         mpc = early_ioremap(physptr, PAGE_SIZE);
 449         size = mpc->length;
 450         early_iounmap(mpc, PAGE_SIZE);
 451         apic_printk(APIC_VERBOSE, "  mpc: %lx-%lx\n", physptr, physptr + size);
 452
 453         return size;
 454 }
 455
 456 static int __init check_physptr(struct mpf_intel *mpf, unsigned int early)
 457 {
 458         struct mpc_table *mpc;
 459         unsigned long size;
 460
 461         size = get_mpc_size(mpf->physptr);
 462         mpc = early_ioremap(mpf->physptr, size);
 463         /*
 464          * Read the physical hardware table.  Anything here will
 465          * override the defaults.
 466          */
 467         if (!smp_read_mpc(mpc, early)) {
 468 #ifdef CONFIG_X86_LOCAL_APIC
 469                 smp_found_config = 0;
 470 #endif
 471                 printk(KERN_ERR "BIOS bug, MP table errors detected!...\n"
 472                         "... disabling SMP support. (tell your hw vendor)\n");
 473                 early_iounmap(mpc, size);
 474                 return -1;
 475         }
 476         early_iounmap(mpc, size);
 477
 478         if (early)
 479                 return -1;
 480
 481 #ifdef CONFIG_X86_IO_APIC
 482         /*
 483          * If there are no explicit MP IRQ entries, then we are
 484          * broken.  We set up most of the low 16 IO-APIC pins to
 485          * ISA defaults and hope it will work.
 486          */
 487         if (!mp_irq_entries) {
 488                 struct mpc_bus bus;
 489
 490                 printk(KERN_ERR "BIOS bug, no explicit IRQ entries, "
 491                        "using default mptable. (tell your hw vendor)\n");
 492
 493                 bus.type = MP_BUS;
 494                 bus.busid = 0;
 495                 memcpy(bus.bustype, "ISA   ", 6);
 496                 MP_bus_info(&bus);
 497
 498                 construct_default_ioirq_mptable(0);
 499         }
 500 #endif
 501
 502         return 0;
 503 }
 504
 505 /*
 506  * Scan the memory blocks for an SMP configuration block.
 507  */
 508 void __init default_get_smp_config(unsigned int early)
 509 {
 510         struct mpf_intel *mpf = mpf_found;
 511
 512         if (!mpf)
 513                 return;
 514
 515         if (acpi_lapic && early)
 516                 return;
 517
 518         /*
 519          * MPS doesn't support hyperthreading, aka only have
 520          * thread 0 apic id in MPS table
 521          */
 522         if (acpi_lapic && acpi_ioapic)
 523                 return;
 524
 525         printk(KERN_INFO "Intel MultiProcessor Specification v1.%d\n",
 526                mpf->specification);
 527 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86_32)
 528         if (mpf->feature2 & (1 << 7)) {
 529                 printk(KERN_INFO "    IMCR and PIC compatibility mode.\n");
 530                 pic_mode = 1;
 531         } else {
 532                 printk(KERN_INFO "    Virtual Wire compatibility mode.\n");
 533                 pic_mode = 0;
 534         }
 535 #endif
 536         /*
 537          * Now see if we need to read further.
 538          */
 539         if (mpf->feature1 != 0) {
 540                 if (early) {
 541                         /*
 542                          * local APIC has default address
 543                          */
 544                         mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
 545                         return;
 546                 }
 547
 548                 printk(KERN_INFO "Default MP configuration #%d\n",
 549                        mpf->feature1);
 550                 construct_default_ISA_mptable(mpf->feature1);
 551
 552         } else if (mpf->physptr) {
 553                 if (check_physptr(mpf, early))
 554                         return;
 555         } else
 556                 BUG();
 557
 558         if (!early)
 559                 printk(KERN_INFO "Processors: %d\n", num_processors);
 560         /*
 561          * Only use the first configuration found.
 562          */
 563 }
 564
 565 static void __init smp_reserve_memory(struct mpf_intel *mpf)
 566 {
 567         unsigned long size = get_mpc_size(mpf->physptr);
 568
 569         memblock_x86_reserve_range(mpf->physptr, mpf->physptr+size, "* MP-table mpc");
 570 }
 571
 572 static int __init smp_scan_config(unsigned long base, unsigned long length)
 573 {
 574         unsigned int *bp = phys_to_virt(base);
 575         struct mpf_intel *mpf;
 576         unsigned long mem;
 577
 578         apic_printk(APIC_VERBOSE, "Scan SMP from %p for %ld bytes.\n",
 579                         bp, length);
 580         BUILD_BUG_ON(sizeof(*mpf) != 16);
 581
 582         while (length > 0) {
 583                 mpf = (struct mpf_intel *)bp;
 584                 if ((*bp == SMP_MAGIC_IDENT) &&
 585                     (mpf->length == 1) &&
 586                     !mpf_checksum((unsigned char *)bp, 16) &&
 587                     ((mpf->specification == 1)
 588                      || (mpf->specification == 4))) {
 589 #ifdef CONFIG_X86_LOCAL_APIC
 590                         smp_found_config = 1;
 591 #endif
 592                         mpf_found = mpf;
 593
 594                         printk(KERN_INFO "found SMP MP-table at [%p] %llx\n",
 595                                mpf, (u64)virt_to_phys(mpf));
 596
 597                         mem = virt_to_phys(mpf);
 598                         memblock_x86_reserve_range(mem, mem + sizeof(*mpf), "* MP-table mpf");
 599                         if (mpf->physptr)
 600                                 smp_reserve_memory(mpf);
 601
 602                         return 1;
 603                 }
 604                 bp += 4;
 605                 length -= 16;
 606         }
 607         return 0;
 608 }
 609
 610 void __init default_find_smp_config(void)
 611 {
 612         unsigned int address;
 613
 614         /*
 615          * FIXME: Linux assumes you have 640K of base ram..
 616          * this continues the error...
 617          *
 618          * 1) Scan the bottom 1K for a signature
 619          * 2) Scan the top 1K of base RAM
 620          * 3) Scan the 64K of bios
 621          */
 622         if (smp_scan_config(0x0, 0x400) ||
 623             smp_scan_config(639 * 0x400, 0x400) ||
 624             smp_scan_config(0xF0000, 0x10000))
 625                 return;
 626         /*
 627          * If it is an SMP machine we should know now, unless the
 628          * configuration is in an EISA/MCA bus machine with an
 629          * extended bios data area.
 630          *
 631          * there is a real-mode segmented pointer pointing to the
 632          * 4K EBDA area at 0x40E, calculate and scan it here.
 633          *
 634          * NOTE! There are Linux loaders that will corrupt the EBDA
 635          * area, and as such this kind of SMP config may be less
 636          * trustworthy, simply because the SMP table may have been
 637          * stomped on during early boot. These loaders are buggy and
 638          * should be fixed.
 639          *
 640          * MP1.4 SPEC states to only scan first 1K of 4K EBDA.
 641          */
 642
 643         address = get_bios_ebda();
 644         if (address)
 645                 smp_scan_config(address, 0x400);
 646 }
 647
 648 #ifdef CONFIG_X86_IO_APIC
 649 static u8 __initdata irq_used[MAX_IRQ_SOURCES];
 650
 651 static int  __init get_MP_intsrc_index(struct mpc_intsrc *m)
 652 {
 653         int i;
 654
 655         if (m->irqtype != mp_INT)
 656                 return 0;
 657
 658         if (m->irqflag != 0x0f)
 659                 return 0;
 660
 661         /* not legacy */
 662
 663         for (i = 0; i < mp_irq_entries; i++) {
 664                 if (mp_irqs[i].irqtype != mp_INT)
 665                         continue;
 666
 667                 if (mp_irqs[i].irqflag != 0x0f)
 668                         continue;
 669
 670                 if (mp_irqs[i].srcbus != m->srcbus)
 671                         continue;
 672                 if (mp_irqs[i].srcbusirq != m->srcbusirq)
 673                         continue;
 674                 if (irq_used[i]) {
 675                         /* already claimed */
 676                         return -2;
 677                 }
 678                 irq_used[i] = 1;
 679                 return i;
 680         }
 681
 682         /* not found */
 683         return -1;
 684 }
 685
 686 #define SPARE_SLOT_NUM 20
 687
 688 static struct mpc_intsrc __initdata *m_spare[SPARE_SLOT_NUM];
 689
 690 static void __init check_irq_src(struct mpc_intsrc *m, int *nr_m_spare)
 691 {
 692         int i;
 693
 694         apic_printk(APIC_VERBOSE, "OLD ");
 695         print_mp_irq_info(m);
 696
 697         i = get_MP_intsrc_index(m);
 698         if (i > 0) {
 699                 memcpy(m, &mp_irqs[i], sizeof(*m));
 700                 apic_printk(APIC_VERBOSE, "NEW ");
 701                 print_mp_irq_info(&mp_irqs[i]);
 702                 return;
 703         }
 704         if (!i) {
 705                 /* legacy, do nothing */
 706                 return;
 707         }
 708         if (*nr_m_spare < SPARE_SLOT_NUM) {
 709                 /*
 710                  * not found (-1), or duplicated (-2) are invalid entries,
 711                  * we need to use the slot later
 712                  */
 713                 m_spare[*nr_m_spare] = m;
 714                 *nr_m_spare += 1;
 715         }
 716 }
 717
 718 static int __init
 719 check_slot(unsigned long mpc_new_phys, unsigned long mpc_new_length, int count)
 720 {
 721         if (!mpc_new_phys || count <= mpc_new_length) {
 722                 WARN(1, "update_mptable: No spare slots (length: %x)\n", count);
 723                 return -1;
 724         }
 725
 726         return 0;
 727 }
 728 #else /* CONFIG_X86_IO_APIC */
 729 static
 730 inline void __init check_irq_src(struct mpc_intsrc *m, int *nr_m_spare) {}
 731 #endif /* CONFIG_X86_IO_APIC */
 732
 733 static int  __init replace_intsrc_all(struct mpc_table *mpc,
 734                                         unsigned long mpc_new_phys,
 735                                         unsigned long mpc_new_length)
 736 {
 737 #ifdef CONFIG_X86_IO_APIC
 738         int i;
 739 #endif
 740         int count = sizeof(*mpc);
 741         int nr_m_spare = 0;
 742         unsigned char *mpt = ((unsigned char *)mpc) + count;
 743
 744         printk(KERN_INFO "mpc_length %x\n", mpc->length);
 745         while (count < mpc->length) {
 746                 switch (*mpt) {
 747                 case MP_PROCESSOR:
 748                         skip_entry(&mpt, &count, sizeof(struct mpc_cpu));
 749                         break;
 750                 case MP_BUS:
 751                         skip_entry(&mpt, &count, sizeof(struct mpc_bus));
 752                         break;
 753                 case MP_IOAPIC:
 754                         skip_entry(&mpt, &count, sizeof(struct mpc_ioapic));
 755                         break;
 756                 case MP_INTSRC:
 757                         check_irq_src((struct mpc_intsrc *)mpt, &nr_m_spare);
 758                         skip_entry(&mpt, &count, sizeof(struct mpc_intsrc));
 759                         break;
 760                 case MP_LINTSRC:
 761                         skip_entry(&mpt, &count, sizeof(struct mpc_lintsrc));
 762                         break;
 763                 default:
 764                         /* wrong mptable */
 765                         smp_dump_mptable(mpc, mpt);
 766                         goto out;
 767                 }
 768         }
 769
 770 #ifdef CONFIG_X86_IO_APIC
 771         for (i = 0; i < mp_irq_entries; i++) {
 772                 if (irq_used[i])
 773                         continue;
 774
 775                 if (mp_irqs[i].irqtype != mp_INT)
 776                         continue;
 777
 778                 if (mp_irqs[i].irqflag != 0x0f)
 779                         continue;
 780
 781                 if (nr_m_spare > 0) {
 782                         apic_printk(APIC_VERBOSE, "*NEW* found\n");
 783                         nr_m_spare--;
 784                         memcpy(m_spare[nr_m_spare], &mp_irqs[i], sizeof(mp_irqs[i]));
 785                         m_spare[nr_m_spare] = NULL;
 786                 } else {
 787                         struct mpc_intsrc *m = (struct mpc_intsrc *)mpt;
 788                         count += sizeof(struct mpc_intsrc);
 789                         if (check_slot(mpc_new_phys, mpc_new_length, count) < 0)
 790                                 goto out;
 791                         memcpy(m, &mp_irqs[i], sizeof(*m));
 792                         mpc->length = count;
 793                         mpt += sizeof(struct mpc_intsrc);
 794                 }
 795                 print_mp_irq_info(&mp_irqs[i]);
 796         }
 797 #endif
 798 out:
 799         /* update checksum */
 800         mpc->checksum = 0;
 801         mpc->checksum -= mpf_checksum((unsigned char *)mpc, mpc->length);
 802
 803         return 0;
 804 }
 805
 806 int enable_update_mptable;
 807
 808 static int __init update_mptable_setup(char *str)
 809 {
 810         enable_update_mptable = 1;
 811 #ifdef CONFIG_PCI
 812         pci_routeirq = 1;
 813 #endif
 814         return 0;
 815 }
 816 early_param("update_mptable", update_mptable_setup);
 817
 818 static unsigned long __initdata mpc_new_phys;
 819 static unsigned long mpc_new_length __initdata = 4096;
 820
 821 /* alloc_mptable or alloc_mptable=4k */
 822 static int __initdata alloc_mptable;
 823 static int __init parse_alloc_mptable_opt(char *p)
 824 {
 825         enable_update_mptable = 1;
 826 #ifdef CONFIG_PCI
 827         pci_routeirq = 1;
 828 #endif
 829         alloc_mptable = 1;
 830         if (!p)
 831                 return 0;
 832         mpc_new_length = memparse(p, &p);
 833         return 0;
 834 }
 835 early_param("alloc_mptable", parse_alloc_mptable_opt);
 836
 837 void __init early_reserve_e820_mpc_new(void)
 838 {
 839         if (enable_update_mptable && alloc_mptable) {
 840                 u64 startt = 0;
 841                 mpc_new_phys = early_reserve_e820(startt, mpc_new_length, 4);
 842         }
 843 }
 844
 845 static int __init update_mp_table(void)
 846 {
 847         char str[16];
 848         char oem[10];
 849         struct mpf_intel *mpf;
 850         struct mpc_table *mpc, *mpc_new;
 851
 852         if (!enable_update_mptable)
 853                 return 0;
 854
 855         mpf = mpf_found;
 856         if (!mpf)
 857                 return 0;
 858
 859         /*
 860          * Now see if we need to go further.
 861          */
 862         if (mpf->feature1 != 0)
 863                 return 0;
 864
 865         if (!mpf->physptr)
 866                 return 0;
 867
 868         mpc = phys_to_virt(mpf->physptr);
 869
 870         if (!smp_check_mpc(mpc, oem, str))
 871                 return 0;
 872
 873         printk(KERN_INFO "mpf: %llx\n", (u64)virt_to_phys(mpf));
 874         printk(KERN_INFO "physptr: %x\n", mpf->physptr);
 875
 876         if (mpc_new_phys && mpc->length > mpc_new_length) {
 877                 mpc_new_phys = 0;
 878                 printk(KERN_INFO "mpc_new_length is %ld, please use alloc_mptable=8k\n",
 879                          mpc_new_length);
 880         }
 881
 882         if (!mpc_new_phys) {
 883                 unsigned char old, new;
 884                 /* check if we can change the position */
 885                 mpc->checksum = 0;
 886                 old = mpf_checksum((unsigned char *)mpc, mpc->length);
 887                 mpc->checksum = 0xff;
 888                 new = mpf_checksum((unsigned char *)mpc, mpc->length);
 889                 if (old == new) {
 890                         printk(KERN_INFO "mpc is readonly, please try alloc_mptable instead\n");
 891                         return 0;
 892                 }
 893                 printk(KERN_INFO "use in-position replacing\n");
 894         } else {
 895                 mpf->physptr = mpc_new_phys;
 896                 mpc_new = phys_to_virt(mpc_new_phys);
 897                 memcpy(mpc_new, mpc, mpc->length);
 898                 mpc = mpc_new;
 899                 /* check if we can modify that */
 900                 if (mpc_new_phys - mpf->physptr) {
 901                         struct mpf_intel *mpf_new;
 902                         /* steal 16 bytes from [0, 1k) */
 903                         printk(KERN_INFO "mpf new: %x\n", 0x400 - 16);
 904                         mpf_new = phys_to_virt(0x400 - 16);
 905                         memcpy(mpf_new, mpf, 16);
 906                         mpf = mpf_new;
 907                         mpf->physptr = mpc_new_phys;
 908                 }
 909                 mpf->checksum = 0;
 910                 mpf->checksum -= mpf_checksum((unsigned char *)mpf, 16);
 911                 printk(KERN_INFO "physptr new: %x\n", mpf->physptr);
 912         }
 913
 914         /*
 915          * only replace the one with mp_INT and
 916          *       MP_IRQ_TRIGGER_LEVEL|MP_IRQ_POLARITY_LOW,
 917          * already in mp_irqs , stored by ... and mp_config_acpi_gsi,
 918          * may need pci=routeirq for all coverage
 919          */
 920         replace_intsrc_all(mpc, mpc_new_phys, mpc_new_length);
 921
 922         return 0;
 923 }
 924
 925 late_initcall(update_mp_table);