git.oblomov.eu Git - linux-2.6/blob - arch/i386/kernel/acpi/boot.c

   1 /*
   2  *  boot.c - Architecture-Specific Low-Level ACPI Boot Support
   3  *
   4  *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
   5  *  Copyright (C) 2001 Jun Nakajima <jun.nakajima@intel.com>
   6  *
   7  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   8  *
   9  *  This program is free software; you can redistribute it and/or modify
  10  *  it under the terms of the GNU General Public License as published by
  11  *  the Free Software Foundation; either version 2 of the License, or
  12  *  (at your option) any later version.
  13  *
  14  *  This program is distributed in the hope that it will be useful,
  15  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  *  GNU General Public License for more details.
  18  *
  19  *  You should have received a copy of the GNU General Public License
  20  *  along with this program; if not, write to the Free Software
  21  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  22  *
  23  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  24  */
  25
  26 #include <linux/init.h>
  27 #include <linux/acpi.h>
  28 #include <linux/efi.h>
  29 #include <linux/cpumask.h>
  30 #include <linux/module.h>
  31 #include <linux/dmi.h>
  32 #include <linux/irq.h>
  33 #include <linux/bootmem.h>
  34 #include <linux/ioport.h>
  35
  36 #include <asm/pgtable.h>
  37 #include <asm/io_apic.h>
  38 #include <asm/apic.h>
  39 #include <asm/io.h>
  40 #include <asm/mpspec.h>
  41
  42 static int __initdata acpi_force = 0;
  43
  44 #ifdef  CONFIG_ACPI
  45 int acpi_disabled = 0;
  46 #else
  47 int acpi_disabled = 1;
  48 #endif
  49 EXPORT_SYMBOL(acpi_disabled);
  50
  51 #ifdef  CONFIG_X86_64
  52
  53 #include <asm/proto.h>
  54
  55 static inline int acpi_madt_oem_check(char *oem_id, char *oem_table_id) { return 0; }
  56
  57
  58 #else                           /* X86 */
  59
  60 #ifdef  CONFIG_X86_LOCAL_APIC
  61 #include <mach_apic.h>
  62 #include <mach_mpparse.h>
  63 #endif                          /* CONFIG_X86_LOCAL_APIC */
  64
  65 #endif                          /* X86 */
  66
  67 #define BAD_MADT_ENTRY(entry, end) (                                        \
  68                 (!entry) || (unsigned long)entry + sizeof(*entry) > end ||  \
  69                 ((acpi_table_entry_header *)entry)->length < sizeof(*entry))
  70
  71 #define PREFIX                  "ACPI: "
  72
  73 int acpi_noirq __initdata;      /* skip ACPI IRQ initialization */
  74 int acpi_pci_disabled __initdata;       /* skip ACPI PCI scan and IRQ initialization */
  75 int acpi_ht __initdata = 1;     /* enable HT */
  76
  77 int acpi_lapic;
  78 int acpi_ioapic;
  79 int acpi_strict;
  80 EXPORT_SYMBOL(acpi_strict);
  81
  82 acpi_interrupt_flags acpi_sci_flags __initdata;
  83 int acpi_sci_override_gsi __initdata;
  84 int acpi_skip_timer_override __initdata;
  85
  86 #ifdef CONFIG_X86_LOCAL_APIC
  87 static u64 acpi_lapic_addr __initdata = APIC_DEFAULT_PHYS_BASE;
  88 #endif
  89
  90 #ifndef __HAVE_ARCH_CMPXCHG
  91 #warning ACPI uses CMPXCHG, i486 and later hardware
  92 #endif
  93
  94 #define MAX_MADT_ENTRIES        256
  95 u8 x86_acpiid_to_apicid[MAX_MADT_ENTRIES] =
  96     {[0 ... MAX_MADT_ENTRIES - 1] = 0xff };
  97 EXPORT_SYMBOL(x86_acpiid_to_apicid);
  98
  99 /* --------------------------------------------------------------------------
 100                               Boot-time Configuration
 101    -------------------------------------------------------------------------- */
 102
 103 /*
 104  * The default interrupt routing model is PIC (8259).  This gets
 105  * overriden if IOAPICs are enumerated (below).
 106  */
 107 enum acpi_irq_model_id acpi_irq_model = ACPI_IRQ_MODEL_PIC;
 108
 109 #ifdef  CONFIG_X86_64
 110
 111 /* rely on all ACPI tables being in the direct mapping */
 112 char *__acpi_map_table(unsigned long phys_addr, unsigned long size)
 113 {
 114         if (!phys_addr || !size)
 115                 return NULL;
 116
 117         if (phys_addr+size <= (end_pfn_map << PAGE_SHIFT) + PAGE_SIZE)
 118                 return __va(phys_addr);
 119
 120         return NULL;
 121 }
 122
 123 #else
 124
 125 /*
 126  * Temporarily use the virtual area starting from FIX_IO_APIC_BASE_END,
 127  * to map the target physical address. The problem is that set_fixmap()
 128  * provides a single page, and it is possible that the page is not
 129  * sufficient.
 130  * By using this area, we can map up to MAX_IO_APICS pages temporarily,
 131  * i.e. until the next __va_range() call.
 132  *
 133  * Important Safety Note:  The fixed I/O APIC page numbers are *subtracted*
 134  * from the fixed base.  That's why we start at FIX_IO_APIC_BASE_END and
 135  * count idx down while incrementing the phys address.
 136  */
 137 char *__acpi_map_table(unsigned long phys, unsigned long size)
 138 {
 139         unsigned long base, offset, mapped_size;
 140         int idx;
 141
 142         if (phys + size < 8 * 1024 * 1024)
 143                 return __va(phys);
 144
 145         offset = phys & (PAGE_SIZE - 1);
 146         mapped_size = PAGE_SIZE - offset;
 147         set_fixmap(FIX_ACPI_END, phys);
 148         base = fix_to_virt(FIX_ACPI_END);
 149
 150         /*
 151          * Most cases can be covered by the below.
 152          */
 153         idx = FIX_ACPI_END;
 154         while (mapped_size < size) {
 155                 if (--idx < FIX_ACPI_BEGIN)
 156                         return NULL;    /* cannot handle this */
 157                 phys += PAGE_SIZE;
 158                 set_fixmap(idx, phys);
 159                 mapped_size += PAGE_SIZE;
 160         }
 161
 162         return ((unsigned char *)base + offset);
 163 }
 164 #endif
 165
 166 #ifdef CONFIG_PCI_MMCONFIG
 167 /* The physical address of the MMCONFIG aperture.  Set from ACPI tables. */
 168 struct acpi_table_mcfg_config *pci_mmcfg_config;
 169 int pci_mmcfg_config_num;
 170
 171 int __init acpi_parse_mcfg(unsigned long phys_addr, unsigned long size)
 172 {
 173         struct acpi_table_mcfg *mcfg;
 174         unsigned long i;
 175         int config_size;
 176
 177         if (!phys_addr || !size)
 178                 return -EINVAL;
 179
 180         mcfg = (struct acpi_table_mcfg *)__acpi_map_table(phys_addr, size);
 181         if (!mcfg) {
 182                 printk(KERN_WARNING PREFIX "Unable to map MCFG\n");
 183                 return -ENODEV;
 184         }
 185
 186         /* how many config structures do we have */
 187         pci_mmcfg_config_num = 0;
 188         i = size - sizeof(struct acpi_table_mcfg);
 189         while (i >= sizeof(struct acpi_table_mcfg_config)) {
 190                 ++pci_mmcfg_config_num;
 191                 i -= sizeof(struct acpi_table_mcfg_config);
 192         };
 193         if (pci_mmcfg_config_num == 0) {
 194                 printk(KERN_ERR PREFIX "MMCONFIG has no entries\n");
 195                 return -ENODEV;
 196         }
 197
 198         config_size = pci_mmcfg_config_num * sizeof(*pci_mmcfg_config);
 199         pci_mmcfg_config = kmalloc(config_size, GFP_KERNEL);
 200         if (!pci_mmcfg_config) {
 201                 printk(KERN_WARNING PREFIX
 202                        "No memory for MCFG config tables\n");
 203                 return -ENOMEM;
 204         }
 205
 206         memcpy(pci_mmcfg_config, &mcfg->config, config_size);
 207         for (i = 0; i < pci_mmcfg_config_num; ++i) {
 208                 if (mcfg->config[i].base_reserved) {
 209                         printk(KERN_ERR PREFIX
 210                                "MMCONFIG not in low 4GB of memory\n");
 211                         kfree(pci_mmcfg_config);
 212                         pci_mmcfg_config_num = 0;
 213                         return -ENODEV;
 214                 }
 215         }
 216
 217         return 0;
 218 }
 219 #endif                          /* CONFIG_PCI_MMCONFIG */
 220
 221 #ifdef CONFIG_X86_LOCAL_APIC
 222 static int __init acpi_parse_madt(unsigned long phys_addr, unsigned long size)
 223 {
 224         struct acpi_table_madt *madt = NULL;
 225
 226         if (!phys_addr || !size || !cpu_has_apic)
 227                 return -EINVAL;
 228
 229         madt = (struct acpi_table_madt *)__acpi_map_table(phys_addr, size);
 230         if (!madt) {
 231                 printk(KERN_WARNING PREFIX "Unable to map MADT\n");
 232                 return -ENODEV;
 233         }
 234
 235         if (madt->lapic_address) {
 236                 acpi_lapic_addr = (u64) madt->lapic_address;
 237
 238                 printk(KERN_DEBUG PREFIX "Local APIC address 0x%08x\n",
 239                        madt->lapic_address);
 240         }
 241
 242         acpi_madt_oem_check(madt->header.oem_id, madt->header.oem_table_id);
 243
 244         return 0;
 245 }
 246
 247 static int __init
 248 acpi_parse_lapic(acpi_table_entry_header * header, const unsigned long end)
 249 {
 250         struct acpi_table_lapic *processor = NULL;
 251
 252         processor = (struct acpi_table_lapic *)header;
 253
 254         if (BAD_MADT_ENTRY(processor, end))
 255                 return -EINVAL;
 256
 257         acpi_table_print_madt_entry(header);
 258
 259         /* Record local apic id only when enabled */
 260         if (processor->flags.enabled)
 261                 x86_acpiid_to_apicid[processor->acpi_id] = processor->id;
 262
 263         /*
 264          * We need to register disabled CPU as well to permit
 265          * counting disabled CPUs. This allows us to size
 266          * cpus_possible_map more accurately, to permit
 267          * to not preallocating memory for all NR_CPUS
 268          * when we use CPU hotplug.
 269          */
 270         mp_register_lapic(processor->id,        /* APIC ID */
 271                           processor->flags.enabled);    /* Enabled? */
 272
 273         return 0;
 274 }
 275
 276 static int __init
 277 acpi_parse_lapic_addr_ovr(acpi_table_entry_header * header,
 278                           const unsigned long end)
 279 {
 280         struct acpi_table_lapic_addr_ovr *lapic_addr_ovr = NULL;
 281
 282         lapic_addr_ovr = (struct acpi_table_lapic_addr_ovr *)header;
 283
 284         if (BAD_MADT_ENTRY(lapic_addr_ovr, end))
 285                 return -EINVAL;
 286
 287         acpi_lapic_addr = lapic_addr_ovr->address;
 288
 289         return 0;
 290 }
 291
 292 static int __init
 293 acpi_parse_lapic_nmi(acpi_table_entry_header * header, const unsigned long end)
 294 {
 295         struct acpi_table_lapic_nmi *lapic_nmi = NULL;
 296
 297         lapic_nmi = (struct acpi_table_lapic_nmi *)header;
 298
 299         if (BAD_MADT_ENTRY(lapic_nmi, end))
 300                 return -EINVAL;
 301
 302         acpi_table_print_madt_entry(header);
 303
 304         if (lapic_nmi->lint != 1)
 305                 printk(KERN_WARNING PREFIX "NMI not connected to LINT 1!\n");
 306
 307         return 0;
 308 }
 309
 310 #endif                          /*CONFIG_X86_LOCAL_APIC */
 311
 312 #ifdef CONFIG_X86_IO_APIC
 313
 314 static int __init
 315 acpi_parse_ioapic(acpi_table_entry_header * header, const unsigned long end)
 316 {
 317         struct acpi_table_ioapic *ioapic = NULL;
 318
 319         ioapic = (struct acpi_table_ioapic *)header;
 320
 321         if (BAD_MADT_ENTRY(ioapic, end))
 322                 return -EINVAL;
 323
 324         acpi_table_print_madt_entry(header);
 325
 326         mp_register_ioapic(ioapic->id,
 327                            ioapic->address, ioapic->global_irq_base);
 328
 329         return 0;
 330 }
 331
 332 /*
 333  * Parse Interrupt Source Override for the ACPI SCI
 334  */
 335 static void acpi_sci_ioapic_setup(u32 bus_irq, u32 gsi, u16 polarity, u16 trigger)
 336 {
 337         if (trigger == 0)       /* compatible SCI trigger is level */
 338                 trigger = 3;
 339
 340         if (polarity == 0)      /* compatible SCI polarity is low */
 341                 polarity = 3;
 342
 343         /* Command-line over-ride via acpi_sci= */
 344         if (acpi_sci_flags.trigger)
 345                 trigger = acpi_sci_flags.trigger;
 346
 347         if (acpi_sci_flags.polarity)
 348                 polarity = acpi_sci_flags.polarity;
 349
 350         /*
 351          * mp_config_acpi_legacy_irqs() already setup IRQs < 16
 352          * If GSI is < 16, this will update its flags,
 353          * else it will create a new mp_irqs[] entry.
 354          */
 355         mp_override_legacy_irq(bus_irq, polarity, trigger, gsi);
 356
 357         /*
 358          * stash over-ride to indicate we've been here
 359          * and for later update of acpi_fadt
 360          */
 361         acpi_sci_override_gsi = bus_irq;
 362         return;
 363 }
 364
 365 static int __init
 366 acpi_parse_int_src_ovr(acpi_table_entry_header * header,
 367                        const unsigned long end)
 368 {
 369         struct acpi_table_int_src_ovr *intsrc = NULL;
 370
 371         intsrc = (struct acpi_table_int_src_ovr *)header;
 372
 373         if (BAD_MADT_ENTRY(intsrc, end))
 374                 return -EINVAL;
 375
 376         acpi_table_print_madt_entry(header);
 377
 378         if (intsrc->bus_irq == acpi_fadt.sci_int) {
 379                 acpi_sci_ioapic_setup(intsrc->bus_irq, intsrc->global_irq,
 380                                       intsrc->flags.polarity,
 381                                       intsrc->flags.trigger);
 382                 return 0;
 383         }
 384
 385         if (acpi_skip_timer_override &&
 386             intsrc->bus_irq == 0 && intsrc->global_irq == 2) {
 387                 printk(PREFIX "BIOS IRQ0 pin2 override ignored.\n");
 388                 return 0;
 389         }
 390
 391         mp_override_legacy_irq(intsrc->bus_irq,
 392                                intsrc->flags.polarity,
 393                                intsrc->flags.trigger, intsrc->global_irq);
 394
 395         return 0;
 396 }
 397
 398 static int __init
 399 acpi_parse_nmi_src(acpi_table_entry_header * header, const unsigned long end)
 400 {
 401         struct acpi_table_nmi_src *nmi_src = NULL;
 402
 403         nmi_src = (struct acpi_table_nmi_src *)header;
 404
 405         if (BAD_MADT_ENTRY(nmi_src, end))
 406                 return -EINVAL;
 407
 408         acpi_table_print_madt_entry(header);
 409
 410         /* TBD: Support nimsrc entries? */
 411
 412         return 0;
 413 }
 414
 415 #endif                          /* CONFIG_X86_IO_APIC */
 416
 417 /*
 418  * acpi_pic_sci_set_trigger()
 419  *
 420  * use ELCR to set PIC-mode trigger type for SCI
 421  *
 422  * If a PIC-mode SCI is not recognized or gives spurious IRQ7's
 423  * it may require Edge Trigger -- use "acpi_sci=edge"
 424  *
 425  * Port 0x4d0-4d1 are ECLR1 and ECLR2, the Edge/Level Control Registers
 426  * for the 8259 PIC.  bit[n] = 1 means irq[n] is Level, otherwise Edge.
 427  * ECLR1 is IRQ's 0-7 (IRQ 0, 1, 2 must be 0)
 428  * ECLR2 is IRQ's 8-15 (IRQ 8, 13 must be 0)
 429  */
 430
 431 void __init acpi_pic_sci_set_trigger(unsigned int irq, u16 trigger)
 432 {
 433         unsigned int mask = 1 << irq;
 434         unsigned int old, new;
 435
 436         /* Real old ELCR mask */
 437         old = inb(0x4d0) | (inb(0x4d1) << 8);
 438
 439         /*
 440          * If we use ACPI to set PCI irq's, then we should clear ELCR
 441          * since we will set it correctly as we enable the PCI irq
 442          * routing.
 443          */
 444         new = acpi_noirq ? old : 0;
 445
 446         /*
 447          * Update SCI information in the ELCR, it isn't in the PCI
 448          * routing tables..
 449          */
 450         switch (trigger) {
 451         case 1:         /* Edge - clear */
 452                 new &= ~mask;
 453                 break;
 454         case 3:         /* Level - set */
 455                 new |= mask;
 456                 break;
 457         }
 458
 459         if (old == new)
 460                 return;
 461
 462         printk(PREFIX "setting ELCR to %04x (from %04x)\n", new, old);
 463         outb(new, 0x4d0);
 464         outb(new >> 8, 0x4d1);
 465 }
 466
 467 int acpi_gsi_to_irq(u32 gsi, unsigned int *irq)
 468 {
 469         *irq = gsi;
 470         return 0;
 471 }
 472
 473 /*
 474  * success: return IRQ number (>=0)
 475  * failure: return < 0
 476  */
 477 int acpi_register_gsi(u32 gsi, int triggering, int polarity)
 478 {
 479         unsigned int irq;
 480         unsigned int plat_gsi = gsi;
 481
 482 #ifdef CONFIG_PCI
 483         /*
 484          * Make sure all (legacy) PCI IRQs are set as level-triggered.
 485          */
 486         if (acpi_irq_model == ACPI_IRQ_MODEL_PIC) {
 487                 extern void eisa_set_level_irq(unsigned int irq);
 488
 489                 if (triggering == ACPI_LEVEL_SENSITIVE)
 490                         eisa_set_level_irq(gsi);
 491         }
 492 #endif
 493
 494 #ifdef CONFIG_X86_IO_APIC
 495         if (acpi_irq_model == ACPI_IRQ_MODEL_IOAPIC) {
 496                 plat_gsi = mp_register_gsi(gsi, triggering, polarity);
 497         }
 498 #endif
 499         acpi_gsi_to_irq(plat_gsi, &irq);
 500         return irq;
 501 }
 502
 503 EXPORT_SYMBOL(acpi_register_gsi);
 504
 505 /*
 506  *  ACPI based hotplug support for CPU
 507  */
 508 #ifdef CONFIG_ACPI_HOTPLUG_CPU
 509 int acpi_map_lsapic(acpi_handle handle, int *pcpu)
 510 {
 511         struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
 512         union acpi_object *obj;
 513         struct acpi_table_lapic *lapic;
 514         cpumask_t tmp_map, new_map;
 515         u8 physid;
 516         int cpu;
 517
 518         if (ACPI_FAILURE(acpi_evaluate_object(handle, "_MAT", NULL, &buffer)))
 519                 return -EINVAL;
 520
 521         if (!buffer.length || !buffer.pointer)
 522                 return -EINVAL;
 523
 524         obj = buffer.pointer;
 525         if (obj->type != ACPI_TYPE_BUFFER ||
 526             obj->buffer.length < sizeof(*lapic)) {
 527                 kfree(buffer.pointer);
 528                 return -EINVAL;
 529         }
 530
 531         lapic = (struct acpi_table_lapic *)obj->buffer.pointer;
 532
 533         if ((lapic->header.type != ACPI_MADT_LAPIC) ||
 534             (!lapic->flags.enabled)) {
 535                 kfree(buffer.pointer);
 536                 return -EINVAL;
 537         }
 538
 539         physid = lapic->id;
 540
 541         kfree(buffer.pointer);
 542         buffer.length = ACPI_ALLOCATE_BUFFER;
 543         buffer.pointer = NULL;
 544
 545         tmp_map = cpu_present_map;
 546         mp_register_lapic(physid, lapic->flags.enabled);
 547
 548         /*
 549          * If mp_register_lapic successfully generates a new logical cpu
 550          * number, then the following will get us exactly what was mapped
 551          */
 552         cpus_andnot(new_map, cpu_present_map, tmp_map);
 553         if (cpus_empty(new_map)) {
 554                 printk ("Unable to map lapic to logical cpu number\n");
 555                 return -EINVAL;
 556         }
 557
 558         cpu = first_cpu(new_map);
 559
 560         *pcpu = cpu;
 561         return 0;
 562 }
 563
 564 EXPORT_SYMBOL(acpi_map_lsapic);
 565
 566 int acpi_unmap_lsapic(int cpu)
 567 {
 568         int i;
 569
 570         for_each_possible_cpu(i) {
 571                 if (x86_acpiid_to_apicid[i] == x86_cpu_to_apicid[cpu]) {
 572                         x86_acpiid_to_apicid[i] = -1;
 573                         break;
 574                 }
 575         }
 576         x86_cpu_to_apicid[cpu] = -1;
 577         cpu_clear(cpu, cpu_present_map);
 578         num_processors--;
 579
 580         return (0);
 581 }
 582
 583 EXPORT_SYMBOL(acpi_unmap_lsapic);
 584 #endif                          /* CONFIG_ACPI_HOTPLUG_CPU */
 585
 586 int acpi_register_ioapic(acpi_handle handle, u64 phys_addr, u32 gsi_base)
 587 {
 588         /* TBD */
 589         return -EINVAL;
 590 }
 591
 592 EXPORT_SYMBOL(acpi_register_ioapic);
 593
 594 int acpi_unregister_ioapic(acpi_handle handle, u32 gsi_base)
 595 {
 596         /* TBD */
 597         return -EINVAL;
 598 }
 599
 600 EXPORT_SYMBOL(acpi_unregister_ioapic);
 601
 602 static unsigned long __init
 603 acpi_scan_rsdp(unsigned long start, unsigned long length)
 604 {
 605         unsigned long offset = 0;
 606         unsigned long sig_len = sizeof("RSD PTR ") - 1;
 607
 608         /*
 609          * Scan all 16-byte boundaries of the physical memory region for the
 610          * RSDP signature.
 611          */
 612         for (offset = 0; offset < length; offset += 16) {
 613                 if (strncmp((char *)(phys_to_virt(start) + offset), "RSD PTR ", sig_len))
 614                         continue;
 615                 return (start + offset);
 616         }
 617
 618         return 0;
 619 }
 620
 621 static int __init acpi_parse_sbf(unsigned long phys_addr, unsigned long size)
 622 {
 623         struct acpi_table_sbf *sb;
 624
 625         if (!phys_addr || !size)
 626                 return -EINVAL;
 627
 628         sb = (struct acpi_table_sbf *)__acpi_map_table(phys_addr, size);
 629         if (!sb) {
 630                 printk(KERN_WARNING PREFIX "Unable to map SBF\n");
 631                 return -ENODEV;
 632         }
 633
 634         sbf_port = sb->sbf_cmos;        /* Save CMOS port */
 635
 636         return 0;
 637 }
 638
 639 #ifdef CONFIG_HPET_TIMER
 640
 641 static int __init acpi_parse_hpet(unsigned long phys, unsigned long size)
 642 {
 643         struct acpi_table_hpet *hpet_tbl;
 644         struct resource *hpet_res;
 645         resource_size_t res_start;
 646
 647         if (!phys || !size)
 648                 return -EINVAL;
 649
 650         hpet_tbl = (struct acpi_table_hpet *)__acpi_map_table(phys, size);
 651         if (!hpet_tbl) {
 652                 printk(KERN_WARNING PREFIX "Unable to map HPET\n");
 653                 return -ENODEV;
 654         }
 655
 656         if (hpet_tbl->addr.space_id != ACPI_SPACE_MEM) {
 657                 printk(KERN_WARNING PREFIX "HPET timers must be located in "
 658                        "memory.\n");
 659                 return -1;
 660         }
 661
 662 #define HPET_RESOURCE_NAME_SIZE 9
 663         hpet_res = alloc_bootmem(sizeof(*hpet_res) + HPET_RESOURCE_NAME_SIZE);
 664         if (hpet_res) {
 665                 memset(hpet_res, 0, sizeof(*hpet_res));
 666                 hpet_res->name = (void *)&hpet_res[1];
 667                 hpet_res->flags = IORESOURCE_MEM | IORESOURCE_BUSY;
 668                 snprintf((char *)hpet_res->name, HPET_RESOURCE_NAME_SIZE,
 669                          "HPET %u", hpet_tbl->number);
 670                 hpet_res->end = (1 * 1024) - 1;
 671         }
 672
 673 #ifdef  CONFIG_X86_64
 674         vxtime.hpet_address = hpet_tbl->addr.addrl |
 675             ((long)hpet_tbl->addr.addrh << 32);
 676
 677         printk(KERN_INFO PREFIX "HPET id: %#x base: %#lx\n",
 678                hpet_tbl->id, vxtime.hpet_address);
 679
 680         res_start = vxtime.hpet_address;
 681 #else                           /* X86 */
 682         {
 683                 extern unsigned long hpet_address;
 684
 685                 hpet_address = hpet_tbl->addr.addrl;
 686                 printk(KERN_INFO PREFIX "HPET id: %#x base: %#lx\n",
 687                        hpet_tbl->id, hpet_address);
 688
 689                 res_start = hpet_address;
 690         }
 691 #endif                          /* X86 */
 692
 693         if (hpet_res) {
 694                 hpet_res->start = res_start;
 695                 hpet_res->end += res_start;
 696                 insert_resource(&iomem_resource, hpet_res);
 697         }
 698
 699         return 0;
 700 }
 701 #else
 702 #define acpi_parse_hpet NULL
 703 #endif
 704
 705 #ifdef CONFIG_X86_PM_TIMER
 706 extern u32 pmtmr_ioport;
 707 #endif
 708
 709 static int __init acpi_parse_fadt(unsigned long phys, unsigned long size)
 710 {
 711         struct fadt_descriptor *fadt = NULL;
 712
 713         fadt = (struct fadt_descriptor *)__acpi_map_table(phys, size);
 714         if (!fadt) {
 715                 printk(KERN_WARNING PREFIX "Unable to map FADT\n");
 716                 return 0;
 717         }
 718         /* initialize sci_int early for INT_SRC_OVR MADT parsing */
 719         acpi_fadt.sci_int = fadt->sci_int;
 720
 721         /* initialize rev and apic_phys_dest_mode for x86_64 genapic */
 722         acpi_fadt.revision = fadt->revision;
 723         acpi_fadt.force_apic_physical_destination_mode =
 724             fadt->force_apic_physical_destination_mode;
 725
 726 #ifdef CONFIG_X86_PM_TIMER
 727         /* detect the location of the ACPI PM Timer */
 728         if (fadt->revision >= FADT2_REVISION_ID) {
 729                 /* FADT rev. 2 */
 730                 if (fadt->xpm_tmr_blk.address_space_id !=
 731                     ACPI_ADR_SPACE_SYSTEM_IO)
 732                         return 0;
 733
 734                 pmtmr_ioport = fadt->xpm_tmr_blk.address;
 735                 /*
 736                  * "X" fields are optional extensions to the original V1.0
 737                  * fields, so we must selectively expand V1.0 fields if the
 738                  * corresponding X field is zero.
 739                  */
 740                 if (!pmtmr_ioport)
 741                         pmtmr_ioport = fadt->V1_pm_tmr_blk;
 742         } else {
 743                 /* FADT rev. 1 */
 744                 pmtmr_ioport = fadt->V1_pm_tmr_blk;
 745         }
 746         if (pmtmr_ioport)
 747                 printk(KERN_INFO PREFIX "PM-Timer IO Port: %#x\n",
 748                        pmtmr_ioport);
 749 #endif
 750         return 0;
 751 }
 752
 753 unsigned long __init acpi_find_rsdp(void)
 754 {
 755         unsigned long rsdp_phys = 0;
 756
 757         if (efi_enabled) {
 758                 if (efi.acpi20 != EFI_INVALID_TABLE_ADDR)
 759                         return efi.acpi20;
 760                 else if (efi.acpi != EFI_INVALID_TABLE_ADDR)
 761                         return efi.acpi;
 762         }
 763         /*
 764          * Scan memory looking for the RSDP signature. First search EBDA (low
 765          * memory) paragraphs and then search upper memory (E0000-FFFFF).
 766          */
 767         rsdp_phys = acpi_scan_rsdp(0, 0x400);
 768         if (!rsdp_phys)
 769                 rsdp_phys = acpi_scan_rsdp(0xE0000, 0x20000);
 770
 771         return rsdp_phys;
 772 }
 773
 774 #ifdef  CONFIG_X86_LOCAL_APIC
 775 /*
 776  * Parse LAPIC entries in MADT
 777  * returns 0 on success, < 0 on error
 778  */
 779 static int __init acpi_parse_madt_lapic_entries(void)
 780 {
 781         int count;
 782
 783         if (!cpu_has_apic)
 784                 return -ENODEV;
 785
 786         /*
 787          * Note that the LAPIC address is obtained from the MADT (32-bit value)
 788          * and (optionally) overriden by a LAPIC_ADDR_OVR entry (64-bit value).
 789          */
 790
 791         count =
 792             acpi_table_parse_madt(ACPI_MADT_LAPIC_ADDR_OVR,
 793                                   acpi_parse_lapic_addr_ovr, 0);
 794         if (count < 0) {
 795                 printk(KERN_ERR PREFIX
 796                        "Error parsing LAPIC address override entry\n");
 797                 return count;
 798         }
 799
 800         mp_register_lapic_address(acpi_lapic_addr);
 801
 802         count = acpi_table_parse_madt(ACPI_MADT_LAPIC, acpi_parse_lapic,
 803                                       MAX_APICS);
 804         if (!count) {
 805                 printk(KERN_ERR PREFIX "No LAPIC entries present\n");
 806                 /* TBD: Cleanup to allow fallback to MPS */
 807                 return -ENODEV;
 808         } else if (count < 0) {
 809                 printk(KERN_ERR PREFIX "Error parsing LAPIC entry\n");
 810                 /* TBD: Cleanup to allow fallback to MPS */
 811                 return count;
 812         }
 813
 814         count =
 815             acpi_table_parse_madt(ACPI_MADT_LAPIC_NMI, acpi_parse_lapic_nmi, 0);
 816         if (count < 0) {
 817                 printk(KERN_ERR PREFIX "Error parsing LAPIC NMI entry\n");
 818                 /* TBD: Cleanup to allow fallback to MPS */
 819                 return count;
 820         }
 821         return 0;
 822 }
 823 #endif                          /* CONFIG_X86_LOCAL_APIC */
 824
 825 #ifdef  CONFIG_X86_IO_APIC
 826 /*
 827  * Parse IOAPIC related entries in MADT
 828  * returns 0 on success, < 0 on error
 829  */
 830 static int __init acpi_parse_madt_ioapic_entries(void)
 831 {
 832         int count;
 833
 834         /*
 835          * ACPI interpreter is required to complete interrupt setup,
 836          * so if it is off, don't enumerate the io-apics with ACPI.
 837          * If MPS is present, it will handle them,
 838          * otherwise the system will stay in PIC mode
 839          */
 840         if (acpi_disabled || acpi_noirq) {
 841                 return -ENODEV;
 842         }
 843
 844         if (!cpu_has_apic)
 845                 return -ENODEV;
 846
 847         /*
 848          * if "noapic" boot option, don't look for IO-APICs
 849          */
 850         if (skip_ioapic_setup) {
 851                 printk(KERN_INFO PREFIX "Skipping IOAPIC probe "
 852                        "due to 'noapic' option.\n");
 853                 return -ENODEV;
 854         }
 855
 856         count =
 857             acpi_table_parse_madt(ACPI_MADT_IOAPIC, acpi_parse_ioapic,
 858                                   MAX_IO_APICS);
 859         if (!count) {
 860                 printk(KERN_ERR PREFIX "No IOAPIC entries present\n");
 861                 return -ENODEV;
 862         } else if (count < 0) {
 863                 printk(KERN_ERR PREFIX "Error parsing IOAPIC entry\n");
 864                 return count;
 865         }
 866
 867         count =
 868             acpi_table_parse_madt(ACPI_MADT_INT_SRC_OVR, acpi_parse_int_src_ovr,
 869                                   NR_IRQ_VECTORS);
 870         if (count < 0) {
 871                 printk(KERN_ERR PREFIX
 872                        "Error parsing interrupt source overrides entry\n");
 873                 /* TBD: Cleanup to allow fallback to MPS */
 874                 return count;
 875         }
 876
 877         /*
 878          * If BIOS did not supply an INT_SRC_OVR for the SCI
 879          * pretend we got one so we can set the SCI flags.
 880          */
 881         if (!acpi_sci_override_gsi)
 882                 acpi_sci_ioapic_setup(acpi_fadt.sci_int, acpi_fadt.sci_int, 0, 0);
 883
 884         /* Fill in identity legacy mapings where no override */
 885         mp_config_acpi_legacy_irqs();
 886
 887         count =
 888             acpi_table_parse_madt(ACPI_MADT_NMI_SRC, acpi_parse_nmi_src,
 889                                   NR_IRQ_VECTORS);
 890         if (count < 0) {
 891                 printk(KERN_ERR PREFIX "Error parsing NMI SRC entry\n");
 892                 /* TBD: Cleanup to allow fallback to MPS */
 893                 return count;
 894         }
 895
 896         return 0;
 897 }
 898 #else
 899 static inline int acpi_parse_madt_ioapic_entries(void)
 900 {
 901         return -1;
 902 }
 903 #endif  /* !CONFIG_X86_IO_APIC */
 904
 905 static void __init acpi_process_madt(void)
 906 {
 907 #ifdef CONFIG_X86_LOCAL_APIC
 908         int count, error;
 909
 910         count = acpi_table_parse(ACPI_APIC, acpi_parse_madt);
 911         if (count >= 1) {
 912
 913                 /*
 914                  * Parse MADT LAPIC entries
 915                  */
 916                 error = acpi_parse_madt_lapic_entries();
 917                 if (!error) {
 918                         acpi_lapic = 1;
 919
 920 #ifdef CONFIG_X86_GENERICARCH
 921                         generic_bigsmp_probe();
 922 #endif
 923                         /*
 924                          * Parse MADT IO-APIC entries
 925                          */
 926                         error = acpi_parse_madt_ioapic_entries();
 927                         if (!error) {
 928                                 acpi_irq_model = ACPI_IRQ_MODEL_IOAPIC;
 929                                 acpi_irq_balance_set(NULL);
 930                                 acpi_ioapic = 1;
 931
 932                                 smp_found_config = 1;
 933                                 clustered_apic_check();
 934                         }
 935                 }
 936                 if (error == -EINVAL) {
 937                         /*
 938                          * Dell Precision Workstation 410, 610 come here.
 939                          */
 940                         printk(KERN_ERR PREFIX
 941                                "Invalid BIOS MADT, disabling ACPI\n");
 942                         disable_acpi();
 943                 }
 944         }
 945 #endif
 946         return;
 947 }
 948
 949 #ifdef __i386__
 950
 951 static int __init disable_acpi_irq(struct dmi_system_id *d)
 952 {
 953         if (!acpi_force) {
 954                 printk(KERN_NOTICE "%s detected: force use of acpi=noirq\n",
 955                        d->ident);
 956                 acpi_noirq_set();
 957         }
 958         return 0;
 959 }
 960
 961 static int __init disable_acpi_pci(struct dmi_system_id *d)
 962 {
 963         if (!acpi_force) {
 964                 printk(KERN_NOTICE "%s detected: force use of pci=noacpi\n",
 965                        d->ident);
 966                 acpi_disable_pci();
 967         }
 968         return 0;
 969 }
 970
 971 static int __init dmi_disable_acpi(struct dmi_system_id *d)
 972 {
 973         if (!acpi_force) {
 974                 printk(KERN_NOTICE "%s detected: acpi off\n", d->ident);
 975                 disable_acpi();
 976         } else {
 977                 printk(KERN_NOTICE
 978                        "Warning: DMI blacklist says broken, but acpi forced\n");
 979         }
 980         return 0;
 981 }
 982
 983 /*
 984  * Limit ACPI to CPU enumeration for HT
 985  */
 986 static int __init force_acpi_ht(struct dmi_system_id *d)
 987 {
 988         if (!acpi_force) {
 989                 printk(KERN_NOTICE "%s detected: force use of acpi=ht\n",
 990                        d->ident);
 991                 disable_acpi();
 992                 acpi_ht = 1;
 993         } else {
 994                 printk(KERN_NOTICE
 995                        "Warning: acpi=force overrules DMI blacklist: acpi=ht\n");
 996         }
 997         return 0;
 998 }
 999
1000 /*
1001  * If your system is blacklisted here, but you find that acpi=force
1002  * works for you, please contact acpi-devel@sourceforge.net
1003  */
1004 static struct dmi_system_id __initdata acpi_dmi_table[] = {
1005         /*
1006          * Boxes that need ACPI disabled
1007          */
1008         {
1009          .callback = dmi_disable_acpi,
1010          .ident = "IBM Thinkpad",
1011          .matches = {
1012                      DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),
1013                      DMI_MATCH(DMI_BOARD_NAME, "2629H1G"),
1014                      },
1015          },
1016
1017         /*
1018          * Boxes that need acpi=ht
1019          */
1020         {
1021          .callback = force_acpi_ht,
1022          .ident = "FSC Primergy T850",
1023          .matches = {
1024                      DMI_MATCH(DMI_SYS_VENDOR, "FUJITSU SIEMENS"),
1025                      DMI_MATCH(DMI_PRODUCT_NAME, "PRIMERGY T850"),
1026                      },
1027          },
1028         {
1029          .callback = force_acpi_ht,
1030          .ident = "DELL GX240",
1031          .matches = {
1032                      DMI_MATCH(DMI_BOARD_VENDOR, "Dell Computer Corporation"),
1033                      DMI_MATCH(DMI_BOARD_NAME, "OptiPlex GX240"),
1034                      },
1035          },
1036         {
1037          .callback = force_acpi_ht,
1038          .ident = "HP VISUALIZE NT Workstation",
1039          .matches = {
1040                      DMI_MATCH(DMI_BOARD_VENDOR, "Hewlett-Packard"),
1041                      DMI_MATCH(DMI_PRODUCT_NAME, "HP VISUALIZE NT Workstation"),
1042                      },
1043          },
1044         {
1045          .callback = force_acpi_ht,
1046          .ident = "Compaq Workstation W8000",
1047          .matches = {
1048                      DMI_MATCH(DMI_SYS_VENDOR, "Compaq"),
1049                      DMI_MATCH(DMI_PRODUCT_NAME, "Workstation W8000"),
1050                      },
1051          },
1052         {
1053          .callback = force_acpi_ht,
1054          .ident = "ASUS P4B266",
1055          .matches = {
1056                      DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1057                      DMI_MATCH(DMI_BOARD_NAME, "P4B266"),
1058                      },
1059          },
1060         {
1061          .callback = force_acpi_ht,
1062          .ident = "ASUS P2B-DS",
1063          .matches = {
1064                      DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1065                      DMI_MATCH(DMI_BOARD_NAME, "P2B-DS"),
1066                      },
1067          },
1068         {
1069          .callback = force_acpi_ht,
1070          .ident = "ASUS CUR-DLS",
1071          .matches = {
1072                      DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1073                      DMI_MATCH(DMI_BOARD_NAME, "CUR-DLS"),
1074                      },
1075          },
1076         {
1077          .callback = force_acpi_ht,
1078          .ident = "ABIT i440BX-W83977",
1079          .matches = {
1080                      DMI_MATCH(DMI_BOARD_VENDOR, "ABIT <http://www.abit.com>"),
1081                      DMI_MATCH(DMI_BOARD_NAME, "i440BX-W83977 (BP6)"),
1082                      },
1083          },
1084         {
1085          .callback = force_acpi_ht,
1086          .ident = "IBM Bladecenter",
1087          .matches = {
1088                      DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),
1089                      DMI_MATCH(DMI_BOARD_NAME, "IBM eServer BladeCenter HS20"),
1090                      },
1091          },
1092         {
1093          .callback = force_acpi_ht,
1094          .ident = "IBM eServer xSeries 360",
1095          .matches = {
1096                      DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),
1097                      DMI_MATCH(DMI_BOARD_NAME, "eServer xSeries 360"),
1098                      },
1099          },
1100         {
1101          .callback = force_acpi_ht,
1102          .ident = "IBM eserver xSeries 330",
1103          .matches = {
1104                      DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),
1105                      DMI_MATCH(DMI_BOARD_NAME, "eserver xSeries 330"),
1106                      },
1107          },
1108         {
1109          .callback = force_acpi_ht,
1110          .ident = "IBM eserver xSeries 440",
1111          .matches = {
1112                      DMI_MATCH(DMI_BOARD_VENDOR, "IBM"),
1113                      DMI_MATCH(DMI_PRODUCT_NAME, "eserver xSeries 440"),
1114                      },
1115          },
1116
1117         /*
1118          * Boxes that need ACPI PCI IRQ routing disabled
1119          */
1120         {
1121          .callback = disable_acpi_irq,
1122          .ident = "ASUS A7V",
1123          .matches = {
1124                      DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC"),
1125                      DMI_MATCH(DMI_BOARD_NAME, "<A7V>"),
1126                      /* newer BIOS, Revision 1011, does work */
1127                      DMI_MATCH(DMI_BIOS_VERSION,
1128                                "ASUS A7V ACPI BIOS Revision 1007"),
1129                      },
1130          },
1131
1132         /*
1133          * Boxes that need ACPI PCI IRQ routing and PCI scan disabled
1134          */
1135         {                       /* _BBN 0 bug */
1136          .callback = disable_acpi_pci,
1137          .ident = "ASUS PR-DLS",
1138          .matches = {
1139                      DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
1140                      DMI_MATCH(DMI_BOARD_NAME, "PR-DLS"),
1141                      DMI_MATCH(DMI_BIOS_VERSION,
1142                                "ASUS PR-DLS ACPI BIOS Revision 1010"),
1143                      DMI_MATCH(DMI_BIOS_DATE, "03/21/2003")
1144                      },
1145          },
1146         {
1147          .callback = disable_acpi_pci,
1148          .ident = "Acer TravelMate 36x Laptop",
1149          .matches = {
1150                      DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
1151                      DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate 360"),
1152                      },
1153          },
1154         {}
1155 };
1156
1157 #endif                          /* __i386__ */
1158
1159 /*
1160  * acpi_boot_table_init() and acpi_boot_init()
1161  *  called from setup_arch(), always.
1162  *      1. checksums all tables
1163  *      2. enumerates lapics
1164  *      3. enumerates io-apics
1165  *
1166  * acpi_table_init() is separate to allow reading SRAT without
1167  * other side effects.
1168  *
1169  * side effects of acpi_boot_init:
1170  *      acpi_lapic = 1 if LAPIC found
1171  *      acpi_ioapic = 1 if IOAPIC found
1172  *      if (acpi_lapic && acpi_ioapic) smp_found_config = 1;
1173  *      if acpi_blacklisted() acpi_disabled = 1;
1174  *      acpi_irq_model=...
1175  *      ...
1176  *
1177  * return value: (currently ignored)
1178  *      0: success
1179  *      !0: failure
1180  */
1181
1182 int __init acpi_boot_table_init(void)
1183 {
1184         int error;
1185
1186 #ifdef __i386__
1187         dmi_check_system(acpi_dmi_table);
1188 #endif
1189
1190         /*
1191          * If acpi_disabled, bail out
1192          * One exception: acpi=ht continues far enough to enumerate LAPICs
1193          */
1194         if (acpi_disabled && !acpi_ht)
1195                 return 1;
1196
1197         /*
1198          * Initialize the ACPI boot-time table parser.
1199          */
1200         error = acpi_table_init();
1201         if (error) {
1202                 disable_acpi();
1203                 return error;
1204         }
1205
1206         acpi_table_parse(ACPI_BOOT, acpi_parse_sbf);
1207
1208         /*
1209          * blacklist may disable ACPI entirely
1210          */
1211         error = acpi_blacklisted();
1212         if (error) {
1213                 if (acpi_force) {
1214                         printk(KERN_WARNING PREFIX "acpi=force override\n");
1215                 } else {
1216                         printk(KERN_WARNING PREFIX "Disabling ACPI support\n");
1217                         disable_acpi();
1218                         return error;
1219                 }
1220         }
1221
1222         return 0;
1223 }
1224
1225 int __init acpi_boot_init(void)
1226 {
1227         /*
1228          * If acpi_disabled, bail out
1229          * One exception: acpi=ht continues far enough to enumerate LAPICs
1230          */
1231         if (acpi_disabled && !acpi_ht)
1232                 return 1;
1233
1234         acpi_table_parse(ACPI_BOOT, acpi_parse_sbf);
1235
1236         /*
1237          * set sci_int and PM timer address
1238          */
1239         acpi_table_parse(ACPI_FADT, acpi_parse_fadt);
1240
1241         /*
1242          * Process the Multiple APIC Description Table (MADT), if present
1243          */
1244         acpi_process_madt();
1245
1246         acpi_table_parse(ACPI_HPET, acpi_parse_hpet);
1247
1248         return 0;
1249 }
1250
1251 static int __init parse_acpi(char *arg)
1252 {
1253         if (!arg)
1254                 return -EINVAL;
1255
1256         /* "acpi=off" disables both ACPI table parsing and interpreter */
1257         if (strcmp(arg, "off") == 0) {
1258                 disable_acpi();
1259         }
1260         /* acpi=force to over-ride black-list */
1261         else if (strcmp(arg, "force") == 0) {
1262                 acpi_force = 1;
1263                 acpi_ht = 1;
1264                 acpi_disabled = 0;
1265         }
1266         /* acpi=strict disables out-of-spec workarounds */
1267         else if (strcmp(arg, "strict") == 0) {
1268                 acpi_strict = 1;
1269         }
1270         /* Limit ACPI just to boot-time to enable HT */
1271         else if (strcmp(arg, "ht") == 0) {
1272                 if (!acpi_force)
1273                         disable_acpi();
1274                 acpi_ht = 1;
1275         }
1276         /* "acpi=noirq" disables ACPI interrupt routing */
1277         else if (strcmp(arg, "noirq") == 0) {
1278                 acpi_noirq_set();
1279         } else {
1280                 /* Core will printk when we return error. */
1281                 return -EINVAL;
1282         }
1283         return 0;
1284 }
1285 early_param("acpi", parse_acpi);
1286
1287 /* FIXME: Using pci= for an ACPI parameter is a travesty. */
1288 static int __init parse_pci(char *arg)
1289 {
1290         if (arg && strcmp(arg, "noacpi") == 0)
1291                 acpi_disable_pci();
1292         return 0;
1293 }
1294 early_param("pci", parse_pci);
1295
1296 #ifdef CONFIG_X86_IO_APIC
1297 static int __init parse_acpi_skip_timer_override(char *arg)
1298 {
1299         acpi_skip_timer_override = 1;
1300         return 0;
1301 }
1302 early_param("acpi_skip_timer_override", parse_acpi_skip_timer_override);
1303 #endif /* CONFIG_X86_IO_APIC */
1304
1305 static int __init setup_acpi_sci(char *s)
1306 {
1307         if (!s)
1308                 return -EINVAL;
1309         if (!strcmp(s, "edge"))
1310                 acpi_sci_flags.trigger = 1;
1311         else if (!strcmp(s, "level"))
1312                 acpi_sci_flags.trigger = 3;
1313         else if (!strcmp(s, "high"))
1314                 acpi_sci_flags.polarity = 1;
1315         else if (!strcmp(s, "low"))
1316                 acpi_sci_flags.polarity = 3;
1317         else
1318                 return -EINVAL;
1319         return 0;
1320 }
1321 early_param("acpi_sci", setup_acpi_sci);