arch/i386/kernel/setup_32.c

   1 /*
   2  *  linux/arch/i386/kernel/setup.c
   3  *
   4  *  Copyright (C) 1995  Linus Torvalds
   5  *
   6  *  Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
   7  *
   8  *  Memory region support
   9  *      David Parsons <orc@pell.chi.il.us>, July-August 1999
  10  *
  11  *  Added E820 sanitization routine (removes overlapping memory regions);
  12  *  Brian Moyle <bmoyle@mvista.com>, February 2001
  13  *
  14  * Moved CPU detection code to cpu/${cpu}.c
  15  *    Patrick Mochel <mochel@osdl.org>, March 2002
  16  *
  17  *  Provisions for empty E820 memory regions (reported by certain BIOSes).
  18  *  Alex Achenbach <xela@slit.de>, December 2002.
  19  *
  20  */
  21
  22 /*
  23  * This file handles the architecture-dependent parts of initialization
  24  */
  25
  26 #include <linux/sched.h>
  27 #include <linux/mm.h>
  28 #include <linux/mmzone.h>
  29 #include <linux/screen_info.h>
  30 #include <linux/ioport.h>
  31 #include <linux/acpi.h>
  32 #include <linux/apm_bios.h>
  33 #include <linux/initrd.h>
  34 #include <linux/bootmem.h>
  35 #include <linux/seq_file.h>
  36 #include <linux/console.h>
  37 #include <linux/mca.h>
  38 #include <linux/root_dev.h>
  39 #include <linux/highmem.h>
  40 #include <linux/module.h>
  41 #include <linux/efi.h>
  42 #include <linux/init.h>
  43 #include <linux/edd.h>
  44 #include <linux/nodemask.h>
  45 #include <linux/kexec.h>
  46 #include <linux/crash_dump.h>
  47 #include <linux/dmi.h>
  48 #include <linux/pfn.h>
  49
  50 #include <video/edid.h>
  51
  52 #include <asm/apic.h>
  53 #include <asm/e820.h>
  54 #include <asm/mpspec.h>
  55 #include <asm/mmzone.h>
  56 #include <asm/setup.h>
  57 #include <asm/arch_hooks.h>
  58 #include <asm/sections.h>
  59 #include <asm/io_apic.h>
  60 #include <asm/ist.h>
  61 #include <asm/io.h>
  62 #include <asm/vmi.h>
  63 #include <setup_arch.h>
  64 #include <bios_ebda.h>
  65
  66 /* This value is set up by the early boot code to point to the value
  67    immediately after the boot time page tables.  It contains a *physical*
  68    address, and must not be in the .bss segment! */
  69 unsigned long init_pg_tables_end __initdata = ~0UL;
  70
  71 int disable_pse __devinitdata = 0;
  72
  73 /*
  74  * Machine setup..
  75  */
  76 extern struct resource code_resource;
  77 extern struct resource data_resource;
  78
  79 /* cpu data as detected by the assembly code in head.S */
  80 struct cpuinfo_x86 new_cpu_data __cpuinitdata = { 0, 0, 0, 0, -1, 1, 0, 0, -1 };
  81 /* common cpu data for all cpus */
  82 struct cpuinfo_x86 boot_cpu_data __read_mostly = { 0, 0, 0, 0, -1, 1, 0, 0, -1 };
  83 EXPORT_SYMBOL(boot_cpu_data);
  84
  85 unsigned long mmu_cr4_features;
  86
  87 /* for MCA, but anyone else can use it if they want */
  88 unsigned int machine_id;
  89 #ifdef CONFIG_MCA
  90 EXPORT_SYMBOL(machine_id);
  91 #endif
  92 unsigned int machine_submodel_id;
  93 unsigned int BIOS_revision;
  94 unsigned int mca_pentium_flag;
  95
  96 /* Boot loader ID as an integer, for the benefit of proc_dointvec */
  97 int bootloader_type;
  98
  99 /* user-defined highmem size */
 100 static unsigned int highmem_pages = -1;
 101
 102 /*
 103  * Setup options
 104  */
 105 struct screen_info screen_info;
 106 EXPORT_SYMBOL(screen_info);
 107 struct apm_info apm_info;
 108 EXPORT_SYMBOL(apm_info);
 109 struct edid_info edid_info;
 110 EXPORT_SYMBOL_GPL(edid_info);
 111 struct ist_info ist_info;
 112 #if defined(CONFIG_X86_SPEEDSTEP_SMI) || \
 113         defined(CONFIG_X86_SPEEDSTEP_SMI_MODULE)
 114 EXPORT_SYMBOL(ist_info);
 115 #endif
 116
 117 extern void early_cpu_init(void);
 118 extern int root_mountflags;
 119
 120 unsigned long saved_videomode;
 121
 122 #define RAMDISK_IMAGE_START_MASK        0x07FF
 123 #define RAMDISK_PROMPT_FLAG             0x8000
 124 #define RAMDISK_LOAD_FLAG               0x4000
 125
 126 static char __initdata command_line[COMMAND_LINE_SIZE];
 127
 128 struct boot_params __initdata boot_params;
 129
 130 #if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE)
 131 struct edd edd;
 132 #ifdef CONFIG_EDD_MODULE
 133 EXPORT_SYMBOL(edd);
 134 #endif
 135 /**
 136  * copy_edd() - Copy the BIOS EDD information
 137  *              from boot_params into a safe place.
 138  *
 139  */
 140 static inline void copy_edd(void)
 141 {
 142      memcpy(edd.mbr_signature, EDD_MBR_SIGNATURE, sizeof(edd.mbr_signature));
 143      memcpy(edd.edd_info, EDD_BUF, sizeof(edd.edd_info));
 144      edd.mbr_signature_nr = EDD_MBR_SIG_NR;
 145      edd.edd_info_nr = EDD_NR;
 146 }
 147 #else
 148 static inline void copy_edd(void)
 149 {
 150 }
 151 #endif
 152
 153 int __initdata user_defined_memmap = 0;
 154
 155 /*
 156  * "mem=nopentium" disables the 4MB page tables.
 157  * "mem=XXX[kKmM]" defines a memory region from HIGH_MEM
 158  * to <mem>, overriding the bios size.
 159  * "memmap=XXX[KkmM]@XXX[KkmM]" defines a memory region from
 160  * <start> to <start>+<mem>, overriding the bios size.
 161  *
 162  * HPA tells me bootloaders need to parse mem=, so no new
 163  * option should be mem=  [also see Documentation/i386/boot.txt]
 164  */
 165 static int __init parse_mem(char *arg)
 166 {
 167         if (!arg)
 168                 return -EINVAL;
 169
 170         if (strcmp(arg, "nopentium") == 0) {
 171                 clear_bit(X86_FEATURE_PSE, boot_cpu_data.x86_capability);
 172                 disable_pse = 1;
 173         } else {
 174                 /* If the user specifies memory size, we
 175                  * limit the BIOS-provided memory map to
 176                  * that size. exactmap can be used to specify
 177                  * the exact map. mem=number can be used to
 178                  * trim the existing memory map.
 179                  */
 180                 unsigned long long mem_size;
 181
 182                 mem_size = memparse(arg, &arg);
 183                 limit_regions(mem_size);
 184                 user_defined_memmap = 1;
 185         }
 186         return 0;
 187 }
 188 early_param("mem", parse_mem);
 189
 190 #ifdef CONFIG_PROC_VMCORE
 191 /* elfcorehdr= specifies the location of elf core header
 192  * stored by the crashed kernel.
 193  */
 194 static int __init parse_elfcorehdr(char *arg)
 195 {
 196         if (!arg)
 197                 return -EINVAL;
 198
 199         elfcorehdr_addr = memparse(arg, &arg);
 200         return 0;
 201 }
 202 early_param("elfcorehdr", parse_elfcorehdr);
 203 #endif /* CONFIG_PROC_VMCORE */
 204
 205 /*
 206  * highmem=size forces highmem to be exactly 'size' bytes.
 207  * This works even on boxes that have no highmem otherwise.
 208  * This also works to reduce highmem size on bigger boxes.
 209  */
 210 static int __init parse_highmem(char *arg)
 211 {
 212         if (!arg)
 213                 return -EINVAL;
 214
 215         highmem_pages = memparse(arg, &arg) >> PAGE_SHIFT;
 216         return 0;
 217 }
 218 early_param("highmem", parse_highmem);
 219
 220 /*
 221  * vmalloc=size forces the vmalloc area to be exactly 'size'
 222  * bytes. This can be used to increase (or decrease) the
 223  * vmalloc area - the default is 128m.
 224  */
 225 static int __init parse_vmalloc(char *arg)
 226 {
 227         if (!arg)
 228                 return -EINVAL;
 229
 230         __VMALLOC_RESERVE = memparse(arg, &arg);
 231         return 0;
 232 }
 233 early_param("vmalloc", parse_vmalloc);
 234
 235 /*
 236  * reservetop=size reserves a hole at the top of the kernel address space which
 237  * a hypervisor can load into later.  Needed for dynamically loaded hypervisors,
 238  * so relocating the fixmap can be done before paging initialization.
 239  */
 240 static int __init parse_reservetop(char *arg)
 241 {
 242         unsigned long address;
 243
 244         if (!arg)
 245                 return -EINVAL;
 246
 247         address = memparse(arg, &arg);
 248         reserve_top_address(address);
 249         return 0;
 250 }
 251 early_param("reservetop", parse_reservetop);
 252
 253 /*
 254  * Determine low and high memory ranges:
 255  */
 256 unsigned long __init find_max_low_pfn(void)
 257 {
 258         unsigned long max_low_pfn;
 259
 260         max_low_pfn = max_pfn;
 261         if (max_low_pfn > MAXMEM_PFN) {
 262                 if (highmem_pages == -1)
 263                         highmem_pages = max_pfn - MAXMEM_PFN;
 264                 if (highmem_pages + MAXMEM_PFN < max_pfn)
 265                         max_pfn = MAXMEM_PFN + highmem_pages;
 266                 if (highmem_pages + MAXMEM_PFN > max_pfn) {
 267                         printk("only %luMB highmem pages available, ignoring highmem size of %uMB.\n", pages_to_mb(max_pfn - MAXMEM_PFN), pages_to_mb(highmem_pages));
 268                         highmem_pages = 0;
 269                 }
 270                 max_low_pfn = MAXMEM_PFN;
 271 #ifndef CONFIG_HIGHMEM
 272                 /* Maximum memory usable is what is directly addressable */
 273                 printk(KERN_WARNING "Warning only %ldMB will be used.\n",
 274                                         MAXMEM>>20);
 275                 if (max_pfn > MAX_NONPAE_PFN)
 276                         printk(KERN_WARNING "Use a HIGHMEM64G enabled kernel.\n");
 277                 else
 278                         printk(KERN_WARNING "Use a HIGHMEM enabled kernel.\n");
 279                 max_pfn = MAXMEM_PFN;
 280 #else /* !CONFIG_HIGHMEM */
 281 #ifndef CONFIG_HIGHMEM64G
 282                 if (max_pfn > MAX_NONPAE_PFN) {
 283                         max_pfn = MAX_NONPAE_PFN;
 284                         printk(KERN_WARNING "Warning only 4GB will be used.\n");
 285                         printk(KERN_WARNING "Use a HIGHMEM64G enabled kernel.\n");
 286                 }
 287 #endif /* !CONFIG_HIGHMEM64G */
 288 #endif /* !CONFIG_HIGHMEM */
 289         } else {
 290                 if (highmem_pages == -1)
 291                         highmem_pages = 0;
 292 #ifdef CONFIG_HIGHMEM
 293                 if (highmem_pages >= max_pfn) {
 294                         printk(KERN_ERR "highmem size specified (%uMB) is bigger than pages available (%luMB)!.\n", pages_to_mb(highmem_pages), pages_to_mb(max_pfn));
 295                         highmem_pages = 0;
 296                 }
 297                 if (highmem_pages) {
 298                         if (max_low_pfn-highmem_pages < 64*1024*1024/PAGE_SIZE){
 299                                 printk(KERN_ERR "highmem size %uMB results in smaller than 64MB lowmem, ignoring it.\n", pages_to_mb(highmem_pages));
 300                                 highmem_pages = 0;
 301                         }
 302                         max_low_pfn -= highmem_pages;
 303                 }
 304 #else
 305                 if (highmem_pages)
 306                         printk(KERN_ERR "ignoring highmem size on non-highmem kernel!\n");
 307 #endif
 308         }
 309         return max_low_pfn;
 310 }
 311
 312 /*
 313  * workaround for Dell systems that neglect to reserve EBDA
 314  */
 315 static void __init reserve_ebda_region(void)
 316 {
 317         unsigned int addr;
 318         addr = get_bios_ebda();
 319         if (addr)
 320                 reserve_bootmem(addr, PAGE_SIZE);
 321 }
 322
 323 #ifndef CONFIG_NEED_MULTIPLE_NODES
 324 void __init setup_bootmem_allocator(void);
 325 static unsigned long __init setup_memory(void)
 326 {
 327         /*
 328          * partially used pages are not usable - thus
 329          * we are rounding upwards:
 330          */
 331         min_low_pfn = PFN_UP(init_pg_tables_end);
 332
 333         find_max_pfn();
 334
 335         max_low_pfn = find_max_low_pfn();
 336
 337 #ifdef CONFIG_HIGHMEM
 338         highstart_pfn = highend_pfn = max_pfn;
 339         if (max_pfn > max_low_pfn) {
 340                 highstart_pfn = max_low_pfn;
 341         }
 342         printk(KERN_NOTICE "%ldMB HIGHMEM available.\n",
 343                 pages_to_mb(highend_pfn - highstart_pfn));
 344         num_physpages = highend_pfn;
 345         high_memory = (void *) __va(highstart_pfn * PAGE_SIZE - 1) + 1;
 346 #else
 347         num_physpages = max_low_pfn;
 348         high_memory = (void *) __va(max_low_pfn * PAGE_SIZE - 1) + 1;
 349 #endif
 350 #ifdef CONFIG_FLATMEM
 351         max_mapnr = num_physpages;
 352 #endif
 353         printk(KERN_NOTICE "%ldMB LOWMEM available.\n",
 354                         pages_to_mb(max_low_pfn));
 355
 356         setup_bootmem_allocator();
 357
 358         return max_low_pfn;
 359 }
 360
 361 void __init zone_sizes_init(void)
 362 {
 363         unsigned long max_zone_pfns[MAX_NR_ZONES];
 364         memset(max_zone_pfns, 0, sizeof(max_zone_pfns));
 365         max_zone_pfns[ZONE_DMA] =
 366                 virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
 367         max_zone_pfns[ZONE_NORMAL] = max_low_pfn;
 368 #ifdef CONFIG_HIGHMEM
 369         max_zone_pfns[ZONE_HIGHMEM] = highend_pfn;
 370         add_active_range(0, 0, highend_pfn);
 371 #else
 372         add_active_range(0, 0, max_low_pfn);
 373 #endif
 374
 375         free_area_init_nodes(max_zone_pfns);
 376 }
 377 #else
 378 extern unsigned long __init setup_memory(void);
 379 extern void zone_sizes_init(void);
 380 #endif /* !CONFIG_NEED_MULTIPLE_NODES */
 381
 382 void __init setup_bootmem_allocator(void)
 383 {
 384         unsigned long bootmap_size;
 385         /*
 386          * Initialize the boot-time allocator (with low memory only):
 387          */
 388         bootmap_size = init_bootmem(min_low_pfn, max_low_pfn);
 389
 390         register_bootmem_low_pages(max_low_pfn);
 391
 392         /*
 393          * Reserve the bootmem bitmap itself as well. We do this in two
 394          * steps (first step was init_bootmem()) because this catches
 395          * the (very unlikely) case of us accidentally initializing the
 396          * bootmem allocator with an invalid RAM area.
 397          */
 398         reserve_bootmem(__pa_symbol(_text), (PFN_PHYS(min_low_pfn) +
 399                          bootmap_size + PAGE_SIZE-1) - __pa_symbol(_text));
 400
 401         /*
 402          * reserve physical page 0 - it's a special BIOS page on many boxes,
 403          * enabling clean reboots, SMP operation, laptop functions.
 404          */
 405         reserve_bootmem(0, PAGE_SIZE);
 406
 407         /* reserve EBDA region, it's a 4K region */
 408         reserve_ebda_region();
 409
 410     /* could be an AMD 768MPX chipset. Reserve a page  before VGA to prevent
 411        PCI prefetch into it (errata #56). Usually the page is reserved anyways,
 412        unless you have no PS/2 mouse plugged in. */
 413         if (boot_cpu_data.x86_vendor == X86_VENDOR_AMD &&
 414             boot_cpu_data.x86 == 6)
 415              reserve_bootmem(0xa0000 - 4096, 4096);
 416
 417 #ifdef CONFIG_SMP
 418         /*
 419          * But first pinch a few for the stack/trampoline stuff
 420          * FIXME: Don't need the extra page at 4K, but need to fix
 421          * trampoline before removing it. (see the GDT stuff)
 422          */
 423         reserve_bootmem(PAGE_SIZE, PAGE_SIZE);
 424 #endif
 425 #ifdef CONFIG_ACPI_SLEEP
 426         /*
 427          * Reserve low memory region for sleep support.
 428          */
 429         acpi_reserve_bootmem();
 430 #endif
 431 #ifdef CONFIG_X86_FIND_SMP_CONFIG
 432         /*
 433          * Find and reserve possible boot-time SMP configuration:
 434          */
 435         find_smp_config();
 436 #endif
 437         numa_kva_reserve();
 438 #ifdef CONFIG_BLK_DEV_INITRD
 439         if (LOADER_TYPE && INITRD_START) {
 440                 if (INITRD_START + INITRD_SIZE <= (max_low_pfn << PAGE_SHIFT)) {
 441                         reserve_bootmem(INITRD_START, INITRD_SIZE);
 442                         initrd_start = INITRD_START + PAGE_OFFSET;
 443                         initrd_end = initrd_start+INITRD_SIZE;
 444                 }
 445                 else {
 446                         printk(KERN_ERR "initrd extends beyond end of memory "
 447                             "(0x%08lx > 0x%08lx)\ndisabling initrd\n",
 448                             INITRD_START + INITRD_SIZE,
 449                             max_low_pfn << PAGE_SHIFT);
 450                         initrd_start = 0;
 451                 }
 452         }
 453 #endif
 454 #ifdef CONFIG_KEXEC
 455         if (crashk_res.start != crashk_res.end)
 456                 reserve_bootmem(crashk_res.start,
 457                         crashk_res.end - crashk_res.start + 1);
 458 #endif
 459 }
 460
 461 /*
 462  * The node 0 pgdat is initialized before all of these because
 463  * it's needed for bootmem.  node>0 pgdats have their virtual
 464  * space allocated before the pagetables are in place to access
 465  * them, so they can't be cleared then.
 466  *
 467  * This should all compile down to nothing when NUMA is off.
 468  */
 469 static void __init remapped_pgdat_init(void)
 470 {
 471         int nid;
 472
 473         for_each_online_node(nid) {
 474                 if (nid != 0)
 475                         memset(NODE_DATA(nid), 0, sizeof(struct pglist_data));
 476         }
 477 }
 478
 479 #ifdef CONFIG_MCA
 480 static void set_mca_bus(int x)
 481 {
 482         MCA_bus = x;
 483 }
 484 #else
 485 static void set_mca_bus(int x) { }
 486 #endif
 487
 488 /* Overridden in paravirt.c if CONFIG_PARAVIRT */
 489 char * __init __attribute__((weak)) memory_setup(void)
 490 {
 491         return machine_specific_memory_setup();
 492 }
 493
 494 /*
 495  * Determine if we were loaded by an EFI loader.  If so, then we have also been
 496  * passed the efi memmap, systab, etc., so we should use these data structures
 497  * for initialization.  Note, the efi init code path is determined by the
 498  * global efi_enabled. This allows the same kernel image to be used on existing
 499  * systems (with a traditional BIOS) as well as on EFI systems.
 500  */
 501 void __init setup_arch(char **cmdline_p)
 502 {
 503         unsigned long max_low_pfn;
 504
 505         memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data));
 506         pre_setup_arch_hook();
 507         early_cpu_init();
 508
 509         /*
 510          * FIXME: This isn't an official loader_type right
 511          * now but does currently work with elilo.
 512          * If we were configured as an EFI kernel, check to make
 513          * sure that we were loaded correctly from elilo and that
 514          * the system table is valid.  If not, then initialize normally.
 515          */
 516 #ifdef CONFIG_EFI
 517         if ((LOADER_TYPE == 0x50) && EFI_SYSTAB)
 518                 efi_enabled = 1;
 519 #endif
 520
 521         ROOT_DEV = old_decode_dev(ORIG_ROOT_DEV);
 522         screen_info = SCREEN_INFO;
 523         edid_info = EDID_INFO;
 524         apm_info.bios = APM_BIOS_INFO;
 525         ist_info = IST_INFO;
 526         saved_videomode = VIDEO_MODE;
 527         if( SYS_DESC_TABLE.length != 0 ) {
 528                 set_mca_bus(SYS_DESC_TABLE.table[3] & 0x2);
 529                 machine_id = SYS_DESC_TABLE.table[0];
 530                 machine_submodel_id = SYS_DESC_TABLE.table[1];
 531                 BIOS_revision = SYS_DESC_TABLE.table[2];
 532         }
 533         bootloader_type = LOADER_TYPE;
 534
 535 #ifdef CONFIG_BLK_DEV_RAM
 536         rd_image_start = RAMDISK_FLAGS & RAMDISK_IMAGE_START_MASK;
 537         rd_prompt = ((RAMDISK_FLAGS & RAMDISK_PROMPT_FLAG) != 0);
 538         rd_doload = ((RAMDISK_FLAGS & RAMDISK_LOAD_FLAG) != 0);
 539 #endif
 540         ARCH_SETUP
 541         if (efi_enabled)
 542                 efi_init();
 543         else {
 544                 printk(KERN_INFO "BIOS-provided physical RAM map:\n");
 545                 print_memory_map(memory_setup());
 546         }
 547
 548         copy_edd();
 549
 550         if (!MOUNT_ROOT_RDONLY)
 551                 root_mountflags &= ~MS_RDONLY;
 552         init_mm.start_code = (unsigned long) _text;
 553         init_mm.end_code = (unsigned long) _etext;
 554         init_mm.end_data = (unsigned long) _edata;
 555         init_mm.brk = init_pg_tables_end + PAGE_OFFSET;
 556
 557         code_resource.start = virt_to_phys(_text);
 558         code_resource.end = virt_to_phys(_etext)-1;
 559         data_resource.start = virt_to_phys(_etext);
 560         data_resource.end = virt_to_phys(_edata)-1;
 561
 562         parse_early_param();
 563
 564         if (user_defined_memmap) {
 565                 printk(KERN_INFO "user-defined physical RAM map:\n");
 566                 print_memory_map("user");
 567         }
 568
 569         strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
 570         *cmdline_p = command_line;
 571
 572         max_low_pfn = setup_memory();
 573
 574 #ifdef CONFIG_VMI
 575         /*
 576          * Must be after max_low_pfn is determined, and before kernel
 577          * pagetables are setup.
 578          */
 579         vmi_init();
 580 #endif
 581
 582         /*
 583          * NOTE: before this point _nobody_ is allowed to allocate
 584          * any memory using the bootmem allocator.  Although the
 585          * alloctor is now initialised only the first 8Mb of the kernel
 586          * virtual address space has been mapped.  All allocations before
 587          * paging_init() has completed must use the alloc_bootmem_low_pages()
 588          * variant (which allocates DMA'able memory) and care must be taken
 589          * not to exceed the 8Mb limit.
 590          */
 591
 592 #ifdef CONFIG_SMP
 593         smp_alloc_memory(); /* AP processor realmode stacks in low memory*/
 594 #endif
 595         paging_init();
 596         remapped_pgdat_init();
 597         sparse_init();
 598         zone_sizes_init();
 599
 600         /*
 601          * NOTE: at this point the bootmem allocator is fully available.
 602          */
 603
 604         paravirt_post_allocator_init();
 605
 606         dmi_scan_machine();
 607
 608 #ifdef CONFIG_X86_GENERICARCH
 609         generic_apic_probe();
 610 #endif
 611         if (efi_enabled)
 612                 efi_map_memmap();
 613
 614 #ifdef CONFIG_ACPI
 615         /*
 616          * Parse the ACPI tables for possible boot-time SMP configuration.
 617          */
 618         acpi_boot_table_init();
 619 #endif
 620
 621 #ifdef CONFIG_PCI
 622 #ifdef CONFIG_X86_IO_APIC
 623         check_acpi_pci();       /* Checks more than just ACPI actually */
 624 #endif
 625 #endif
 626
 627 #ifdef CONFIG_ACPI
 628         acpi_boot_init();
 629
 630 #if defined(CONFIG_SMP) && defined(CONFIG_X86_PC)
 631         if (def_to_bigsmp)
 632                 printk(KERN_WARNING "More than 8 CPUs detected and "
 633                         "CONFIG_X86_PC cannot handle it.\nUse "
 634                         "CONFIG_X86_GENERICARCH or CONFIG_X86_BIGSMP.\n");
 635 #endif
 636 #endif
 637 #ifdef CONFIG_X86_LOCAL_APIC
 638         if (smp_found_config)
 639                 get_smp_config();
 640 #endif
 641
 642         e820_register_memory();
 643         e820_mark_nosave_regions();
 644
 645 #ifdef CONFIG_VT
 646 #if defined(CONFIG_VGA_CONSOLE)
 647         if (!efi_enabled || (efi_mem_type(0xa0000) != EFI_CONVENTIONAL_MEMORY))
 648                 conswitchp = &vga_con;
 649 #elif defined(CONFIG_DUMMY_CONSOLE)
 650         conswitchp = &dummy_con;
 651 #endif
 652 #endif
 653 }