arch/x86/kernel/mpparse.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *      Intel Multiprocessor Specification 1.1 and 1.4
   4  *      compliant MP-table parsing routines.
   5  *
   6  *      (c) 1995 Alan Cox, Building #3 <alan@lxorguk.ukuu.org.uk>
   7  *      (c) 1998, 1999, 2000, 2009 Ingo Molnar <mingo@redhat.com>
   8  *      (c) 2008 Alexey Starikovskiy <astarikovskiy@suse.de>
   9  */
  10
  11 #include <linux/mm.h>
  12 #include <linux/init.h>
  13 #include <linux/delay.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/smp.h>
  20 #include <linux/pci.h>
  21
  22 #include <asm/irqdomain.h>
  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/api.h>
  30 #include <asm/setup.h>
  31 #include <asm/smp.h>
  32
  33 #include <asm/apic.h>
  34 /*
  35  * Checksum an MP configuration block.
  36  */
  37
  38 static int __init mpf_checksum(unsigned char *mp, int len)
  39 {
  40         int sum = 0;
  41
  42         while (len--)
  43                 sum += *mp++;
  44
  45         return sum & 0xFF;
  46 }
  47
  48 int __init default_mpc_apic_id(struct mpc_cpu *m)
  49 {
  50         return m->apicid;
  51 }
  52
  53 static void __init MP_processor_info(struct mpc_cpu *m)
  54 {
  55         int apicid;
  56         char *bootup_cpu = "";
  57
  58         if (!(m->cpuflag & CPU_ENABLED)) {
  59                 disabled_cpus++;
  60                 return;
  61         }
  62
  63         apicid = x86_init.mpparse.mpc_apic_id(m);
  64
  65         if (m->cpuflag & CPU_BOOTPROCESSOR) {
  66                 bootup_cpu = " (Bootup-CPU)";
  67                 boot_cpu_physical_apicid = m->apicid;
  68         }
  69
  70         pr_info("Processor #%d%s\n", m->apicid, bootup_cpu);
  71         generic_processor_info(apicid, m->apicver);
  72 }
  73
  74 #ifdef CONFIG_X86_IO_APIC
  75 void __init default_mpc_oem_bus_info(struct mpc_bus *m, char *str)
  76 {
  77         memcpy(str, m->bustype, 6);
  78         str[6] = 0;
  79         apic_printk(APIC_VERBOSE, "Bus #%d is %s\n", m->busid, str);
  80 }
  81
  82 static void __init MP_bus_info(struct mpc_bus *m)
  83 {
  84         char str[7];
  85
  86         x86_init.mpparse.mpc_oem_bus_info(m, str);
  87
  88 #if MAX_MP_BUSSES < 256
  89         if (m->busid >= MAX_MP_BUSSES) {
  90                 pr_warn("MP table busid value (%d) for bustype %s is too large, max. supported is %d\n",
  91                         m->busid, str, MAX_MP_BUSSES - 1);
  92                 return;
  93         }
  94 #endif
  95
  96         set_bit(m->busid, mp_bus_not_pci);
  97         if (strncmp(str, BUSTYPE_ISA, sizeof(BUSTYPE_ISA) - 1) == 0) {
  98 #ifdef CONFIG_EISA
  99                 mp_bus_id_to_type[m->busid] = MP_BUS_ISA;
 100 #endif
 101         } else if (strncmp(str, BUSTYPE_PCI, sizeof(BUSTYPE_PCI) - 1) == 0) {
 102                 if (x86_init.mpparse.mpc_oem_pci_bus)
 103                         x86_init.mpparse.mpc_oem_pci_bus(m);
 104
 105                 clear_bit(m->busid, mp_bus_not_pci);
 106 #ifdef CONFIG_EISA
 107                 mp_bus_id_to_type[m->busid] = MP_BUS_PCI;
 108         } else if (strncmp(str, BUSTYPE_EISA, sizeof(BUSTYPE_EISA) - 1) == 0) {
 109                 mp_bus_id_to_type[m->busid] = MP_BUS_EISA;
 110 #endif
 111         } else
 112                 pr_warn("Unknown bustype %s - ignoring\n", str);
 113 }
 114
 115 static void __init MP_ioapic_info(struct mpc_ioapic *m)
 116 {
 117         struct ioapic_domain_cfg cfg = {
 118                 .type = IOAPIC_DOMAIN_LEGACY,
 119                 .ops = &mp_ioapic_irqdomain_ops,
 120         };
 121
 122         if (m->flags & MPC_APIC_USABLE)
 123                 mp_register_ioapic(m->apicid, m->apicaddr, gsi_top, &cfg);
 124 }
 125
 126 static void __init print_mp_irq_info(struct mpc_intsrc *mp_irq)
 127 {
 128         apic_printk(APIC_VERBOSE,
 129                 "Int: type %d, pol %d, trig %d, bus %02x, IRQ %02x, APIC ID %x, APIC INT %02x\n",
 130                 mp_irq->irqtype, mp_irq->irqflag & 3,
 131                 (mp_irq->irqflag >> 2) & 3, mp_irq->srcbus,
 132                 mp_irq->srcbusirq, mp_irq->dstapic, mp_irq->dstirq);
 133 }
 134
 135 #else /* CONFIG_X86_IO_APIC */
 136 static inline void __init MP_bus_info(struct mpc_bus *m) {}
 137 static inline void __init MP_ioapic_info(struct mpc_ioapic *m) {}
 138 #endif /* CONFIG_X86_IO_APIC */
 139
 140 static void __init MP_lintsrc_info(struct mpc_lintsrc *m)
 141 {
 142         apic_printk(APIC_VERBOSE,
 143                 "Lint: type %d, pol %d, trig %d, bus %02x, IRQ %02x, APIC ID %x, APIC LINT %02x\n",
 144                 m->irqtype, m->irqflag & 3, (m->irqflag >> 2) & 3, m->srcbusid,
 145                 m->srcbusirq, m->destapic, m->destapiclint);
 146 }
 147
 148 /*
 149  * Read/parse the MPC
 150  */
 151 static int __init smp_check_mpc(struct mpc_table *mpc, char *oem, char *str)
 152 {
 153
 154         if (memcmp(mpc->signature, MPC_SIGNATURE, 4)) {
 155                 pr_err("MPTABLE: bad signature [%c%c%c%c]!\n",
 156                        mpc->signature[0], mpc->signature[1],
 157                        mpc->signature[2], mpc->signature[3]);
 158                 return 0;
 159         }
 160         if (mpf_checksum((unsigned char *)mpc, mpc->length)) {
 161                 pr_err("MPTABLE: checksum error!\n");
 162                 return 0;
 163         }
 164         if (mpc->spec != 0x01 && mpc->spec != 0x04) {
 165                 pr_err("MPTABLE: bad table version (%d)!!\n", mpc->spec);
 166                 return 0;
 167         }
 168         if (!mpc->lapic) {
 169                 pr_err("MPTABLE: null local APIC address!\n");
 170                 return 0;
 171         }
 172         memcpy(oem, mpc->oem, 8);
 173         oem[8] = 0;
 174         pr_info("MPTABLE: OEM ID: %s\n", oem);
 175
 176         memcpy(str, mpc->productid, 12);
 177         str[12] = 0;
 178
 179         pr_info("MPTABLE: Product ID: %s\n", str);
 180
 181         pr_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         pr_err("Your mptable is wrong, contact your HW vendor!\n");
 195         pr_cont("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         /* Initialize the lapic mapping */
 214         if (!acpi_lapic)
 215                 register_lapic_address(mpc->lapic);
 216
 217         if (early)
 218                 return 1;
 219
 220         if (mpc->oemptr)
 221                 x86_init.mpparse.smp_read_mpc_oem(mpc);
 222
 223         /*
 224          *      Now process the configuration blocks.
 225          */
 226         x86_init.mpparse.mpc_record(0);
 227
 228         while (count < mpc->length) {
 229                 switch (*mpt) {
 230                 case MP_PROCESSOR:
 231                         /* ACPI may have already provided this data */
 232                         if (!acpi_lapic)
 233                                 MP_processor_info((struct mpc_cpu *)mpt);
 234                         skip_entry(&mpt, &count, sizeof(struct mpc_cpu));
 235                         break;
 236                 case MP_BUS:
 237                         MP_bus_info((struct mpc_bus *)mpt);
 238                         skip_entry(&mpt, &count, sizeof(struct mpc_bus));
 239                         break;
 240                 case MP_IOAPIC:
 241                         MP_ioapic_info((struct mpc_ioapic *)mpt);
 242                         skip_entry(&mpt, &count, sizeof(struct mpc_ioapic));
 243                         break;
 244                 case MP_INTSRC:
 245                         mp_save_irq((struct mpc_intsrc *)mpt);
 246                         skip_entry(&mpt, &count, sizeof(struct mpc_intsrc));
 247                         break;
 248                 case MP_LINTSRC:
 249                         MP_lintsrc_info((struct mpc_lintsrc *)mpt);
 250                         skip_entry(&mpt, &count, sizeof(struct mpc_lintsrc));
 251                         break;
 252                 default:
 253                         /* wrong mptable */
 254                         smp_dump_mptable(mpc, mpt);
 255                         count = mpc->length;
 256                         break;
 257                 }
 258                 x86_init.mpparse.mpc_record(1);
 259         }
 260
 261         if (!num_processors)
 262                 pr_err("MPTABLE: no processors registered!\n");
 263         return num_processors;
 264 }
 265
 266 #ifdef CONFIG_X86_IO_APIC
 267
 268 static int __init ELCR_trigger(unsigned int irq)
 269 {
 270         unsigned int port;
 271
 272         port = 0x4d0 + (irq >> 3);
 273         return (inb(port) >> (irq & 7)) & 1;
 274 }
 275
 276 static void __init construct_default_ioirq_mptable(int mpc_default_type)
 277 {
 278         struct mpc_intsrc intsrc;
 279         int i;
 280         int ELCR_fallback = 0;
 281
 282         intsrc.type = MP_INTSRC;
 283         intsrc.irqflag = MP_IRQTRIG_DEFAULT | MP_IRQPOL_DEFAULT;
 284         intsrc.srcbus = 0;
 285         intsrc.dstapic = mpc_ioapic_id(0);
 286
 287         intsrc.irqtype = mp_INT;
 288
 289         /*
 290          *  If true, we have an ISA/PCI system with no IRQ entries
 291          *  in the MP table. To prevent the PCI interrupts from being set up
 292          *  incorrectly, we try to use the ELCR. The sanity check to see if
 293          *  there is good ELCR data is very simple - IRQ0, 1, 2 and 13 can
 294          *  never be level sensitive, so we simply see if the ELCR agrees.
 295          *  If it does, we assume it's valid.
 296          */
 297         if (mpc_default_type == 5) {
 298                 pr_info("ISA/PCI bus type with no IRQ information... falling back to ELCR\n");
 299
 300                 if (ELCR_trigger(0) || ELCR_trigger(1) || ELCR_trigger(2) ||
 301                     ELCR_trigger(13))
 302                         pr_err("ELCR contains invalid data... not using ELCR\n");
 303                 else {
 304                         pr_info("Using ELCR to identify PCI interrupts\n");
 305                         ELCR_fallback = 1;
 306                 }
 307         }
 308
 309         for (i = 0; i < 16; i++) {
 310                 switch (mpc_default_type) {
 311                 case 2:
 312                         if (i == 0 || i == 13)
 313                                 continue;       /* IRQ0 & IRQ13 not connected */
 314                         /* fall through */
 315                 default:
 316                         if (i == 2)
 317                                 continue;       /* IRQ2 is never connected */
 318                 }
 319
 320                 if (ELCR_fallback) {
 321                         /*
 322                          *  If the ELCR indicates a level-sensitive interrupt, we
 323                          *  copy that information over to the MP table in the
 324                          *  irqflag field (level sensitive, active high polarity).
 325                          */
 326                         if (ELCR_trigger(i)) {
 327                                 intsrc.irqflag = MP_IRQTRIG_LEVEL |
 328                                                  MP_IRQPOL_ACTIVE_HIGH;
 329                         } else {
 330                                 intsrc.irqflag = MP_IRQTRIG_DEFAULT |
 331                                                  MP_IRQPOL_DEFAULT;
 332                         }
 333                 }
 334
 335                 intsrc.srcbusirq = i;
 336                 intsrc.dstirq = i ? i : 2;      /* IRQ0 to INTIN2 */
 337                 mp_save_irq(&intsrc);
 338         }
 339
 340         intsrc.irqtype = mp_ExtINT;
 341         intsrc.srcbusirq = 0;
 342         intsrc.dstirq = 0;      /* 8259A to INTIN0 */
 343         mp_save_irq(&intsrc);
 344 }
 345
 346
 347 static void __init construct_ioapic_table(int mpc_default_type)
 348 {
 349         struct mpc_ioapic ioapic;
 350         struct mpc_bus bus;
 351
 352         bus.type = MP_BUS;
 353         bus.busid = 0;
 354         switch (mpc_default_type) {
 355         default:
 356                 pr_err("???\nUnknown standard configuration %d\n",
 357                        mpc_default_type);
 358                 /* fall through */
 359         case 1:
 360         case 5:
 361                 memcpy(bus.bustype, "ISA   ", 6);
 362                 break;
 363         case 2:
 364         case 6:
 365         case 3:
 366                 memcpy(bus.bustype, "EISA  ", 6);
 367                 break;
 368         }
 369         MP_bus_info(&bus);
 370         if (mpc_default_type > 4) {
 371                 bus.busid = 1;
 372                 memcpy(bus.bustype, "PCI   ", 6);
 373                 MP_bus_info(&bus);
 374         }
 375
 376         ioapic.type     = MP_IOAPIC;
 377         ioapic.apicid   = 2;
 378         ioapic.apicver  = mpc_default_type > 4 ? 0x10 : 0x01;
 379         ioapic.flags    = MPC_APIC_USABLE;
 380         ioapic.apicaddr = IO_APIC_DEFAULT_PHYS_BASE;
 381         MP_ioapic_info(&ioapic);
 382
 383         /*
 384          * We set up most of the low 16 IO-APIC pins according to MPS rules.
 385          */
 386         construct_default_ioirq_mptable(mpc_default_type);
 387 }
 388 #else
 389 static inline void __init construct_ioapic_table(int mpc_default_type) { }
 390 #endif
 391
 392 static inline void __init construct_default_ISA_mptable(int mpc_default_type)
 393 {
 394         struct mpc_cpu processor;
 395         struct mpc_lintsrc lintsrc;
 396         int linttypes[2] = { mp_ExtINT, mp_NMI };
 397         int i;
 398
 399         /*
 400          * local APIC has default address
 401          */
 402         mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
 403
 404         /*
 405          * 2 CPUs, numbered 0 & 1.
 406          */
 407         processor.type = MP_PROCESSOR;
 408         /* Either an integrated APIC or a discrete 82489DX. */
 409         processor.apicver = mpc_default_type > 4 ? 0x10 : 0x01;
 410         processor.cpuflag = CPU_ENABLED;
 411         processor.cpufeature = (boot_cpu_data.x86 << 8) |
 412             (boot_cpu_data.x86_model << 4) | boot_cpu_data.x86_stepping;
 413         processor.featureflag = boot_cpu_data.x86_capability[CPUID_1_EDX];
 414         processor.reserved[0] = 0;
 415         processor.reserved[1] = 0;
 416         for (i = 0; i < 2; i++) {
 417                 processor.apicid = i;
 418                 MP_processor_info(&processor);
 419         }
 420
 421         construct_ioapic_table(mpc_default_type);
 422
 423         lintsrc.type = MP_LINTSRC;
 424         lintsrc.irqflag = MP_IRQTRIG_DEFAULT | MP_IRQPOL_DEFAULT;
 425         lintsrc.srcbusid = 0;
 426         lintsrc.srcbusirq = 0;
 427         lintsrc.destapic = MP_APIC_ALL;
 428         for (i = 0; i < 2; i++) {
 429                 lintsrc.irqtype = linttypes[i];
 430                 lintsrc.destapiclint = i;
 431                 MP_lintsrc_info(&lintsrc);
 432         }
 433 }
 434
 435 static unsigned long mpf_base;
 436 static bool mpf_found;
 437
 438 static unsigned long __init get_mpc_size(unsigned long physptr)
 439 {
 440         struct mpc_table *mpc;
 441         unsigned long size;
 442
 443         mpc = early_memremap(physptr, PAGE_SIZE);
 444         size = mpc->length;
 445         early_memunmap(mpc, PAGE_SIZE);
 446         apic_printk(APIC_VERBOSE, "  mpc: %lx-%lx\n", physptr, physptr + size);
 447
 448         return size;
 449 }
 450
 451 static int __init check_physptr(struct mpf_intel *mpf, unsigned int early)
 452 {
 453         struct mpc_table *mpc;
 454         unsigned long size;
 455
 456         size = get_mpc_size(mpf->physptr);
 457         mpc = early_memremap(mpf->physptr, size);
 458
 459         /*
 460          * Read the physical hardware table.  Anything here will
 461          * override the defaults.
 462          */
 463         if (!smp_read_mpc(mpc, early)) {
 464 #ifdef CONFIG_X86_LOCAL_APIC
 465                 smp_found_config = 0;
 466 #endif
 467                 pr_err("BIOS bug, MP table errors detected!...\n");
 468                 pr_cont("... disabling SMP support. (tell your hw vendor)\n");
 469                 early_memunmap(mpc, size);
 470                 return -1;
 471         }
 472         early_memunmap(mpc, size);
 473
 474         if (early)
 475                 return -1;
 476
 477 #ifdef CONFIG_X86_IO_APIC
 478         /*
 479          * If there are no explicit MP IRQ entries, then we are
 480          * broken.  We set up most of the low 16 IO-APIC pins to
 481          * ISA defaults and hope it will work.
 482          */
 483         if (!mp_irq_entries) {
 484                 struct mpc_bus bus;
 485
 486                 pr_err("BIOS bug, no explicit IRQ entries, using default mptable. (tell your hw vendor)\n");
 487
 488                 bus.type = MP_BUS;
 489                 bus.busid = 0;
 490                 memcpy(bus.bustype, "ISA   ", 6);
 491                 MP_bus_info(&bus);
 492
 493                 construct_default_ioirq_mptable(0);
 494         }
 495 #endif
 496
 497         return 0;
 498 }
 499
 500 /*
 501  * Scan the memory blocks for an SMP configuration block.
 502  */
 503 void __init default_get_smp_config(unsigned int early)
 504 {
 505         struct mpf_intel *mpf;
 506
 507         if (!smp_found_config)
 508                 return;
 509
 510         if (!mpf_found)
 511                 return;
 512
 513         if (acpi_lapic && early)
 514                 return;
 515
 516         /*
 517          * MPS doesn't support hyperthreading, aka only have
 518          * thread 0 apic id in MPS table
 519          */
 520         if (acpi_lapic && acpi_ioapic)
 521                 return;
 522
 523         mpf = early_memremap(mpf_base, sizeof(*mpf));
 524         if (!mpf) {
 525                 pr_err("MPTABLE: error mapping MP table\n");
 526                 return;
 527         }
 528
 529         pr_info("Intel MultiProcessor Specification v1.%d\n",
 530                 mpf->specification);
 531 #if defined(CONFIG_X86_LOCAL_APIC) && defined(CONFIG_X86_32)
 532         if (mpf->feature2 & (1 << 7)) {
 533                 pr_info("    IMCR and PIC compatibility mode.\n");
 534                 pic_mode = 1;
 535         } else {
 536                 pr_info("    Virtual Wire compatibility mode.\n");
 537                 pic_mode = 0;
 538         }
 539 #endif
 540         /*
 541          * Now see if we need to read further.
 542          */
 543         if (mpf->feature1) {
 544                 if (early) {
 545                         /*
 546                          * local APIC has default address
 547                          */
 548                         mp_lapic_addr = APIC_DEFAULT_PHYS_BASE;
 549                         return;
 550                 }
 551
 552                 pr_info("Default MP configuration #%d\n", mpf->feature1);
 553                 construct_default_ISA_mptable(mpf->feature1);
 554
 555         } else if (mpf->physptr) {
 556                 if (check_physptr(mpf, early)) {
 557                         early_memunmap(mpf, sizeof(*mpf));
 558                         return;
 559                 }
 560         } else
 561                 BUG();
 562
 563         if (!early)
 564                 pr_info("Processors: %d\n", num_processors);
 565         /*
 566          * Only use the first configuration found.
 567          */
 568
 569         early_memunmap(mpf, sizeof(*mpf));
 570 }
 571
 572 static void __init smp_reserve_memory(struct mpf_intel *mpf)
 573 {
 574         memblock_reserve(mpf->physptr, get_mpc_size(mpf->physptr));
 575 }
 576
 577 static int __init smp_scan_config(unsigned long base, unsigned long length)
 578 {
 579         unsigned int *bp;
 580         struct mpf_intel *mpf;
 581         int ret = 0;
 582
 583         apic_printk(APIC_VERBOSE, "Scan for SMP in [mem %#010lx-%#010lx]\n",
 584                     base, base + length - 1);
 585         BUILD_BUG_ON(sizeof(*mpf) != 16);
 586
 587         while (length > 0) {
 588                 bp = early_memremap(base, length);
 589                 mpf = (struct mpf_intel *)bp;
 590                 if ((*bp == SMP_MAGIC_IDENT) &&
 591                     (mpf->length == 1) &&
 592                     !mpf_checksum((unsigned char *)bp, 16) &&
 593                     ((mpf->specification == 1)
 594                      || (mpf->specification == 4))) {
 595 #ifdef CONFIG_X86_LOCAL_APIC
 596                         smp_found_config = 1;
 597 #endif
 598                         mpf_base = base;
 599                         mpf_found = true;
 600
 601                         pr_info("found SMP MP-table at [mem %#010lx-%#010lx]\n",
 602                                 base, base + sizeof(*mpf) - 1);
 603
 604                         memblock_reserve(base, sizeof(*mpf));
 605                         if (mpf->physptr)
 606                                 smp_reserve_memory(mpf);
 607
 608                         ret = 1;
 609                 }
 610                 early_memunmap(bp, length);
 611
 612                 if (ret)
 613                         break;
 614
 615                 base += 16;
 616                 length -= 16;
 617         }
 618         return ret;
 619 }
 620
 621 void __init default_find_smp_config(void)
 622 {
 623         unsigned int address;
 624
 625         /*
 626          * FIXME: Linux assumes you have 640K of base ram..
 627          * this continues the error...
 628          *
 629          * 1) Scan the bottom 1K for a signature
 630          * 2) Scan the top 1K of base RAM
 631          * 3) Scan the 64K of bios
 632          */
 633         if (smp_scan_config(0x0, 0x400) ||
 634             smp_scan_config(639 * 0x400, 0x400) ||
 635             smp_scan_config(0xF0000, 0x10000))
 636                 return;
 637         /*
 638          * If it is an SMP machine we should know now, unless the
 639          * configuration is in an EISA bus machine with an
 640          * extended bios data area.
 641          *
 642          * there is a real-mode segmented pointer pointing to the
 643          * 4K EBDA area at 0x40E, calculate and scan it here.
 644          *
 645          * NOTE! There are Linux loaders that will corrupt the EBDA
 646          * area, and as such this kind of SMP config may be less
 647          * trustworthy, simply because the SMP table may have been
 648          * stomped on during early boot. These loaders are buggy and
 649          * should be fixed.
 650          *
 651          * MP1.4 SPEC states to only scan first 1K of 4K EBDA.
 652          */
 653
 654         address = get_bios_ebda();
 655         if (address)
 656                 smp_scan_config(address, 0x400);
 657 }
 658
 659 #ifdef CONFIG_X86_IO_APIC
 660 static u8 __initdata irq_used[MAX_IRQ_SOURCES];
 661
 662 static int  __init get_MP_intsrc_index(struct mpc_intsrc *m)
 663 {
 664         int i;
 665
 666         if (m->irqtype != mp_INT)
 667                 return 0;
 668
 669         if (m->irqflag != (MP_IRQTRIG_LEVEL | MP_IRQPOL_ACTIVE_LOW))
 670                 return 0;
 671
 672         /* not legacy */
 673
 674         for (i = 0; i < mp_irq_entries; i++) {
 675                 if (mp_irqs[i].irqtype != mp_INT)
 676                         continue;
 677
 678                 if (mp_irqs[i].irqflag != (MP_IRQTRIG_LEVEL |
 679                                            MP_IRQPOL_ACTIVE_LOW))
 680                         continue;
 681
 682                 if (mp_irqs[i].srcbus != m->srcbus)
 683                         continue;
 684                 if (mp_irqs[i].srcbusirq != m->srcbusirq)
 685                         continue;
 686                 if (irq_used[i]) {
 687                         /* already claimed */
 688                         return -2;
 689                 }
 690                 irq_used[i] = 1;
 691                 return i;
 692         }
 693
 694         /* not found */
 695         return -1;
 696 }
 697
 698 #define SPARE_SLOT_NUM 20
 699
 700 static struct mpc_intsrc __initdata *m_spare[SPARE_SLOT_NUM];
 701
 702 static void __init check_irq_src(struct mpc_intsrc *m, int *nr_m_spare)
 703 {
 704         int i;
 705
 706         apic_printk(APIC_VERBOSE, "OLD ");
 707         print_mp_irq_info(m);
 708
 709         i = get_MP_intsrc_index(m);
 710         if (i > 0) {
 711                 memcpy(m, &mp_irqs[i], sizeof(*m));
 712                 apic_printk(APIC_VERBOSE, "NEW ");
 713                 print_mp_irq_info(&mp_irqs[i]);
 714                 return;
 715         }
 716         if (!i) {
 717                 /* legacy, do nothing */
 718                 return;
 719         }
 720         if (*nr_m_spare < SPARE_SLOT_NUM) {
 721                 /*
 722                  * not found (-1), or duplicated (-2) are invalid entries,
 723                  * we need to use the slot later
 724                  */
 725                 m_spare[*nr_m_spare] = m;
 726                 *nr_m_spare += 1;
 727         }
 728 }
 729
 730 static int __init
 731 check_slot(unsigned long mpc_new_phys, unsigned long mpc_new_length, int count)
 732 {
 733         if (!mpc_new_phys || count <= mpc_new_length) {
 734                 WARN(1, "update_mptable: No spare slots (length: %x)\n", count);
 735                 return -1;
 736         }
 737
 738         return 0;
 739 }
 740 #else /* CONFIG_X86_IO_APIC */
 741 static
 742 inline void __init check_irq_src(struct mpc_intsrc *m, int *nr_m_spare) {}
 743 #endif /* CONFIG_X86_IO_APIC */
 744
 745 static int  __init replace_intsrc_all(struct mpc_table *mpc,
 746                                         unsigned long mpc_new_phys,
 747                                         unsigned long mpc_new_length)
 748 {
 749 #ifdef CONFIG_X86_IO_APIC
 750         int i;
 751 #endif
 752         int count = sizeof(*mpc);
 753         int nr_m_spare = 0;
 754         unsigned char *mpt = ((unsigned char *)mpc) + count;
 755
 756         pr_info("mpc_length %x\n", mpc->length);
 757         while (count < mpc->length) {
 758                 switch (*mpt) {
 759                 case MP_PROCESSOR:
 760                         skip_entry(&mpt, &count, sizeof(struct mpc_cpu));
 761                         break;
 762                 case MP_BUS:
 763                         skip_entry(&mpt, &count, sizeof(struct mpc_bus));
 764                         break;
 765                 case MP_IOAPIC:
 766                         skip_entry(&mpt, &count, sizeof(struct mpc_ioapic));
 767                         break;
 768                 case MP_INTSRC:
 769                         check_irq_src((struct mpc_intsrc *)mpt, &nr_m_spare);
 770                         skip_entry(&mpt, &count, sizeof(struct mpc_intsrc));
 771                         break;
 772                 case MP_LINTSRC:
 773                         skip_entry(&mpt, &count, sizeof(struct mpc_lintsrc));
 774                         break;
 775                 default:
 776                         /* wrong mptable */
 777                         smp_dump_mptable(mpc, mpt);
 778                         goto out;
 779                 }
 780         }
 781
 782 #ifdef CONFIG_X86_IO_APIC
 783         for (i = 0; i < mp_irq_entries; i++) {
 784                 if (irq_used[i])
 785                         continue;
 786
 787                 if (mp_irqs[i].irqtype != mp_INT)
 788                         continue;
 789
 790                 if (mp_irqs[i].irqflag != (MP_IRQTRIG_LEVEL |
 791                                            MP_IRQPOL_ACTIVE_LOW))
 792                         continue;
 793
 794                 if (nr_m_spare > 0) {
 795                         apic_printk(APIC_VERBOSE, "*NEW* found\n");
 796                         nr_m_spare--;
 797                         memcpy(m_spare[nr_m_spare], &mp_irqs[i], sizeof(mp_irqs[i]));
 798                         m_spare[nr_m_spare] = NULL;
 799                 } else {
 800                         struct mpc_intsrc *m = (struct mpc_intsrc *)mpt;
 801                         count += sizeof(struct mpc_intsrc);
 802                         if (check_slot(mpc_new_phys, mpc_new_length, count) < 0)
 803                                 goto out;
 804                         memcpy(m, &mp_irqs[i], sizeof(*m));
 805                         mpc->length = count;
 806                         mpt += sizeof(struct mpc_intsrc);
 807                 }
 808                 print_mp_irq_info(&mp_irqs[i]);
 809         }
 810 #endif
 811 out:
 812         /* update checksum */
 813         mpc->checksum = 0;
 814         mpc->checksum -= mpf_checksum((unsigned char *)mpc, mpc->length);
 815
 816         return 0;
 817 }
 818
 819 int enable_update_mptable;
 820
 821 static int __init update_mptable_setup(char *str)
 822 {
 823         enable_update_mptable = 1;
 824 #ifdef CONFIG_PCI
 825         pci_routeirq = 1;
 826 #endif
 827         return 0;
 828 }
 829 early_param("update_mptable", update_mptable_setup);
 830
 831 static unsigned long __initdata mpc_new_phys;
 832 static unsigned long mpc_new_length __initdata = 4096;
 833
 834 /* alloc_mptable or alloc_mptable=4k */
 835 static int __initdata alloc_mptable;
 836 static int __init parse_alloc_mptable_opt(char *p)
 837 {
 838         enable_update_mptable = 1;
 839 #ifdef CONFIG_PCI
 840         pci_routeirq = 1;
 841 #endif
 842         alloc_mptable = 1;
 843         if (!p)
 844                 return 0;
 845         mpc_new_length = memparse(p, &p);
 846         return 0;
 847 }
 848 early_param("alloc_mptable", parse_alloc_mptable_opt);
 849
 850 void __init e820__memblock_alloc_reserved_mpc_new(void)
 851 {
 852         if (enable_update_mptable && alloc_mptable)
 853                 mpc_new_phys = e820__memblock_alloc_reserved(mpc_new_length, 4);
 854 }
 855
 856 static int __init update_mp_table(void)
 857 {
 858         char str[16];
 859         char oem[10];
 860         struct mpf_intel *mpf;
 861         struct mpc_table *mpc, *mpc_new;
 862         unsigned long size;
 863
 864         if (!enable_update_mptable)
 865                 return 0;
 866
 867         if (!mpf_found)
 868                 return 0;
 869
 870         mpf = early_memremap(mpf_base, sizeof(*mpf));
 871         if (!mpf) {
 872                 pr_err("MPTABLE: mpf early_memremap() failed\n");
 873                 return 0;
 874         }
 875
 876         /*
 877          * Now see if we need to go further.
 878          */
 879         if (mpf->feature1)
 880                 goto do_unmap_mpf;
 881
 882         if (!mpf->physptr)
 883                 goto do_unmap_mpf;
 884
 885         size = get_mpc_size(mpf->physptr);
 886         mpc = early_memremap(mpf->physptr, size);
 887         if (!mpc) {
 888                 pr_err("MPTABLE: mpc early_memremap() failed\n");
 889                 goto do_unmap_mpf;
 890         }
 891
 892         if (!smp_check_mpc(mpc, oem, str))
 893                 goto do_unmap_mpc;
 894
 895         pr_info("mpf: %llx\n", (u64)mpf_base);
 896         pr_info("physptr: %x\n", mpf->physptr);
 897
 898         if (mpc_new_phys && mpc->length > mpc_new_length) {
 899                 mpc_new_phys = 0;
 900                 pr_info("mpc_new_length is %ld, please use alloc_mptable=8k\n",
 901                         mpc_new_length);
 902         }
 903
 904         if (!mpc_new_phys) {
 905                 unsigned char old, new;
 906                 /* check if we can change the position */
 907                 mpc->checksum = 0;
 908                 old = mpf_checksum((unsigned char *)mpc, mpc->length);
 909                 mpc->checksum = 0xff;
 910                 new = mpf_checksum((unsigned char *)mpc, mpc->length);
 911                 if (old == new) {
 912                         pr_info("mpc is readonly, please try alloc_mptable instead\n");
 913                         goto do_unmap_mpc;
 914                 }
 915                 pr_info("use in-position replacing\n");
 916         } else {
 917                 mpc_new = early_memremap(mpc_new_phys, mpc_new_length);
 918                 if (!mpc_new) {
 919                         pr_err("MPTABLE: new mpc early_memremap() failed\n");
 920                         goto do_unmap_mpc;
 921                 }
 922                 mpf->physptr = mpc_new_phys;
 923                 memcpy(mpc_new, mpc, mpc->length);
 924                 early_memunmap(mpc, size);
 925                 mpc = mpc_new;
 926                 size = mpc_new_length;
 927                 /* check if we can modify that */
 928                 if (mpc_new_phys - mpf->physptr) {
 929                         struct mpf_intel *mpf_new;
 930                         /* steal 16 bytes from [0, 1k) */
 931                         mpf_new = early_memremap(0x400 - 16, sizeof(*mpf_new));
 932                         if (!mpf_new) {
 933                                 pr_err("MPTABLE: new mpf early_memremap() failed\n");
 934                                 goto do_unmap_mpc;
 935                         }
 936                         pr_info("mpf new: %x\n", 0x400 - 16);
 937                         memcpy(mpf_new, mpf, 16);
 938                         early_memunmap(mpf, sizeof(*mpf));
 939                         mpf = mpf_new;
 940                         mpf->physptr = mpc_new_phys;
 941                 }
 942                 mpf->checksum = 0;
 943                 mpf->checksum -= mpf_checksum((unsigned char *)mpf, 16);
 944                 pr_info("physptr new: %x\n", mpf->physptr);
 945         }
 946
 947         /*
 948          * only replace the one with mp_INT and
 949          *       MP_IRQ_TRIGGER_LEVEL|MP_IRQ_POLARITY_LOW,
 950          * already in mp_irqs , stored by ... and mp_config_acpi_gsi,
 951          * may need pci=routeirq for all coverage
 952          */
 953         replace_intsrc_all(mpc, mpc_new_phys, mpc_new_length);
 954
 955 do_unmap_mpc:
 956         early_memunmap(mpc, size);
 957
 958 do_unmap_mpf:
 959         early_memunmap(mpf, sizeof(*mpf));
 960
 961         return 0;
 962 }
 963
 964 late_initcall(update_mp_table);