arch/x86/kernel/setup_32.c

   1 /*
   2  *  Copyright (C) 1995  Linus Torvalds
   3  *
   4  *  Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
   5  *
   6  *  Memory region support
   7  *      David Parsons <orc@pell.chi.il.us>, July-August 1999
   8  *
   9  *  Added E820 sanitization routine (removes overlapping memory regions);
  10  *  Brian Moyle <bmoyle@mvista.com>, February 2001
  11  *
  12  * Moved CPU detection code to cpu/${cpu}.c
  13  *    Patrick Mochel <mochel@osdl.org>, March 2002
  14  *
  15  *  Provisions for empty E820 memory regions (reported by certain BIOSes).
  16  *  Alex Achenbach <xela@slit.de>, December 2002.
  17  *
  18  */
  19
  20 /*
  21  * This file handles the architecture-dependent parts of initialization
  22  */
  23
  24 #include <linux/sched.h>
  25 #include <linux/mm.h>
  26 #include <linux/mmzone.h>
  27 #include <linux/screen_info.h>
  28 #include <linux/ioport.h>
  29 #include <linux/acpi.h>
  30 #include <linux/apm_bios.h>
  31 #include <linux/initrd.h>
  32 #include <linux/bootmem.h>
  33 #include <linux/seq_file.h>
  34 #include <linux/console.h>
  35 #include <linux/mca.h>
  36 #include <linux/root_dev.h>
  37 #include <linux/highmem.h>
  38 #include <linux/module.h>
  39 #include <linux/efi.h>
  40 #include <linux/init.h>
  41 #include <linux/edd.h>
  42 #include <linux/iscsi_ibft.h>
  43 #include <linux/nodemask.h>
  44 #include <linux/kexec.h>
  45 #include <linux/dmi.h>
  46 #include <linux/pfn.h>
  47 #include <linux/pci.h>
  48 #include <asm/pci-direct.h>
  49 #include <linux/init_ohci1394_dma.h>
  50 #include <linux/kvm_para.h>
  51
  52 #include <linux/errno.h>
  53 #include <linux/kernel.h>
  54 #include <linux/stddef.h>
  55 #include <linux/unistd.h>
  56 #include <linux/ptrace.h>
  57 #include <linux/slab.h>
  58 #include <linux/user.h>
  59 #include <linux/delay.h>
  60 #include <linux/highmem.h>
  61
  62 #include <linux/kallsyms.h>
  63 #include <linux/edd.h>
  64 #include <linux/iscsi_ibft.h>
  65 #include <linux/kexec.h>
  66 #include <linux/cpufreq.h>
  67 #include <linux/dma-mapping.h>
  68 #include <linux/ctype.h>
  69 #include <linux/uaccess.h>
  70
  71 #include <linux/percpu.h>
  72 #include <linux/crash_dump.h>
  73
  74 #include <video/edid.h>
  75
  76 #include <asm/mtrr.h>
  77 #include <asm/apic.h>
  78 #include <asm/e820.h>
  79 #include <asm/mpspec.h>
  80 #include <asm/setup.h>
  81 #include <asm/arch_hooks.h>
  82 #include <asm/sections.h>
  83 #include <asm/dmi.h>
  84 #include <asm/io_apic.h>
  85 #include <asm/ist.h>
  86 #include <asm/vmi.h>
  87 #include <setup_arch.h>
  88 #include <asm/bios_ebda.h>
  89 #include <asm/cacheflush.h>
  90 #include <asm/processor.h>
  91 #include <asm/bugs.h>
  92
  93 #include <asm/system.h>
  94 #include <asm/vsyscall.h>
  95 #include <asm/smp.h>
  96 #include <asm/desc.h>
  97 #include <asm/dma.h>
  98 #include <asm/gart.h>
  99 #include <asm/mmu_context.h>
 100 #include <asm/proto.h>
 101
 102 #include <mach_apic.h>
 103 #ifdef CONFIG_PARAVIRT
 104 #include <asm/paravirt.h>
 105 #else
 106 #define ARCH_SETUP
 107 #endif
 108
 109 #include <asm/percpu.h>
 110 #include <asm/sections.h>
 111 #include <asm/topology.h>
 112 #include <asm/apicdef.h>
 113 #ifdef CONFIG_X86_32
 114 #include <asm/highmem.h>
 115 #endif
 116
 117 /* This value is set up by the early boot code to point to the value
 118    immediately after the boot time page tables.  It contains a *physical*
 119    address, and must not be in the .bss segment! */
 120 unsigned long init_pg_tables_start __initdata = ~0UL;
 121 unsigned long init_pg_tables_end __initdata = ~0UL;
 122
 123 /*
 124  * Machine setup..
 125  */
 126 static struct resource data_resource = {
 127         .name   = "Kernel data",
 128         .start  = 0,
 129         .end    = 0,
 130         .flags  = IORESOURCE_BUSY | IORESOURCE_MEM
 131 };
 132
 133 static struct resource code_resource = {
 134         .name   = "Kernel code",
 135         .start  = 0,
 136         .end    = 0,
 137         .flags  = IORESOURCE_BUSY | IORESOURCE_MEM
 138 };
 139
 140 static struct resource bss_resource = {
 141         .name   = "Kernel bss",
 142         .start  = 0,
 143         .end    = 0,
 144         .flags  = IORESOURCE_BUSY | IORESOURCE_MEM
 145 };
 146
 147
 148 #ifdef CONFIG_X86_32
 149 static struct resource video_ram_resource = {
 150         .name   = "Video RAM area",
 151         .start  = 0xa0000,
 152         .end    = 0xbffff,
 153         .flags  = IORESOURCE_BUSY | IORESOURCE_MEM
 154 };
 155
 156 /* cpu data as detected by the assembly code in head.S */
 157 struct cpuinfo_x86 new_cpu_data __cpuinitdata = {0, 0, 0, 0, -1, 1, 0, 0, -1};
 158 /* common cpu data for all cpus */
 159 struct cpuinfo_x86 boot_cpu_data __read_mostly = {0, 0, 0, 0, -1, 1, 0, 0, -1};
 160 EXPORT_SYMBOL(boot_cpu_data);
 161 static void set_mca_bus(int x)
 162 {
 163 #ifdef CONFIG_MCA
 164         MCA_bus = x;
 165 #endif
 166 }
 167
 168 unsigned int def_to_bigsmp;
 169
 170 /* for MCA, but anyone else can use it if they want */
 171 unsigned int machine_id;
 172 unsigned int machine_submodel_id;
 173 unsigned int BIOS_revision;
 174
 175 struct apm_info apm_info;
 176 EXPORT_SYMBOL(apm_info);
 177
 178 #if defined(CONFIG_X86_SPEEDSTEP_SMI) || \
 179         defined(CONFIG_X86_SPEEDSTEP_SMI_MODULE)
 180 struct ist_info ist_info;
 181 EXPORT_SYMBOL(ist_info);
 182 #else
 183 struct ist_info ist_info;
 184 #endif
 185
 186 #else
 187 struct cpuinfo_x86 boot_cpu_data __read_mostly;
 188 EXPORT_SYMBOL(boot_cpu_data);
 189 #endif
 190
 191
 192 #if !defined(CONFIG_X86_PAE) || defined(CONFIG_X86_64)
 193 unsigned long mmu_cr4_features;
 194 #else
 195 unsigned long mmu_cr4_features = X86_CR4_PAE;
 196 #endif
 197
 198 /* Boot loader ID as an integer, for the benefit of proc_dointvec */
 199 int bootloader_type;
 200
 201 /*
 202  * Early DMI memory
 203  */
 204 int dmi_alloc_index;
 205 char dmi_alloc_data[DMI_MAX_DATA];
 206
 207 /*
 208  * Setup options
 209  */
 210 struct screen_info screen_info;
 211 EXPORT_SYMBOL(screen_info);
 212 struct edid_info edid_info;
 213 EXPORT_SYMBOL_GPL(edid_info);
 214
 215 extern int root_mountflags;
 216
 217 unsigned long saved_video_mode;
 218
 219 #define RAMDISK_IMAGE_START_MASK        0x07FF
 220 #define RAMDISK_PROMPT_FLAG             0x8000
 221 #define RAMDISK_LOAD_FLAG               0x4000
 222
 223 static char __initdata command_line[COMMAND_LINE_SIZE];
 224
 225 #if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE)
 226 struct edd edd;
 227 #ifdef CONFIG_EDD_MODULE
 228 EXPORT_SYMBOL(edd);
 229 #endif
 230 /**
 231  * copy_edd() - Copy the BIOS EDD information
 232  *              from boot_params into a safe place.
 233  *
 234  */
 235 static inline void copy_edd(void)
 236 {
 237      memcpy(edd.mbr_signature, boot_params.edd_mbr_sig_buffer,
 238             sizeof(edd.mbr_signature));
 239      memcpy(edd.edd_info, boot_params.eddbuf, sizeof(edd.edd_info));
 240      edd.mbr_signature_nr = boot_params.edd_mbr_sig_buf_entries;
 241      edd.edd_info_nr = boot_params.eddbuf_entries;
 242 }
 243 #else
 244 static inline void copy_edd(void)
 245 {
 246 }
 247 #endif
 248
 249 #ifdef CONFIG_BLK_DEV_INITRD
 250
 251 #ifdef CONFIG_X86_32
 252
 253 #define MAX_MAP_CHUNK   (NR_FIX_BTMAPS << PAGE_SHIFT)
 254 static void __init relocate_initrd(void)
 255 {
 256
 257         u64 ramdisk_image = boot_params.hdr.ramdisk_image;
 258         u64 ramdisk_size  = boot_params.hdr.ramdisk_size;
 259         u64 end_of_lowmem = max_low_pfn << PAGE_SHIFT;
 260         u64 ramdisk_here;
 261         unsigned long slop, clen, mapaddr;
 262         char *p, *q;
 263
 264         /* We need to move the initrd down into lowmem */
 265         ramdisk_here = find_e820_area(0, end_of_lowmem, ramdisk_size,
 266                                          PAGE_SIZE);
 267
 268         if (ramdisk_here == -1ULL)
 269                 panic("Cannot find place for new RAMDISK of size %lld\n",
 270                          ramdisk_size);
 271
 272         /* Note: this includes all the lowmem currently occupied by
 273            the initrd, we rely on that fact to keep the data intact. */
 274         reserve_early(ramdisk_here, ramdisk_here + ramdisk_size,
 275                          "NEW RAMDISK");
 276         initrd_start = ramdisk_here + PAGE_OFFSET;
 277         initrd_end   = initrd_start + ramdisk_size;
 278         printk(KERN_INFO "Allocated new RAMDISK: %08llx - %08llx\n",
 279                          ramdisk_here, ramdisk_here + ramdisk_size);
 280
 281         q = (char *)initrd_start;
 282
 283         /* Copy any lowmem portion of the initrd */
 284         if (ramdisk_image < end_of_lowmem) {
 285                 clen = end_of_lowmem - ramdisk_image;
 286                 p = (char *)__va(ramdisk_image);
 287                 memcpy(q, p, clen);
 288                 q += clen;
 289                 ramdisk_image += clen;
 290                 ramdisk_size  -= clen;
 291         }
 292
 293         /* Copy the highmem portion of the initrd */
 294         while (ramdisk_size) {
 295                 slop = ramdisk_image & ~PAGE_MASK;
 296                 clen = ramdisk_size;
 297                 if (clen > MAX_MAP_CHUNK-slop)
 298                         clen = MAX_MAP_CHUNK-slop;
 299                 mapaddr = ramdisk_image & PAGE_MASK;
 300                 p = early_ioremap(mapaddr, clen+slop);
 301                 memcpy(q, p+slop, clen);
 302                 early_iounmap(p, clen+slop);
 303                 q += clen;
 304                 ramdisk_image += clen;
 305                 ramdisk_size  -= clen;
 306         }
 307         /* high pages is not converted by early_res_to_bootmem */
 308         ramdisk_image = boot_params.hdr.ramdisk_image;
 309         ramdisk_size  = boot_params.hdr.ramdisk_size;
 310         printk(KERN_INFO "Move RAMDISK from %016llx - %016llx to"
 311                 " %08llx - %08llx\n",
 312                 ramdisk_image, ramdisk_image + ramdisk_size - 1,
 313                 ramdisk_here, ramdisk_here + ramdisk_size - 1);
 314 }
 315 #endif
 316
 317 static void __init reserve_initrd(void)
 318 {
 319         u64 ramdisk_image = boot_params.hdr.ramdisk_image;
 320         u64 ramdisk_size  = boot_params.hdr.ramdisk_size;
 321         u64 ramdisk_end   = ramdisk_image + ramdisk_size;
 322         u64 end_of_lowmem = max_low_pfn << PAGE_SHIFT;
 323
 324         if (!boot_params.hdr.type_of_loader ||
 325             !ramdisk_image || !ramdisk_size)
 326                 return;         /* No initrd provided by bootloader */
 327
 328         initrd_start = 0;
 329
 330         if (ramdisk_size >= (end_of_lowmem>>1)) {
 331                 free_early(ramdisk_image, ramdisk_end);
 332                 printk(KERN_ERR "initrd too large to handle, "
 333                        "disabling initrd\n");
 334                 return;
 335         }
 336
 337         printk(KERN_INFO "RAMDISK: %08llx - %08llx\n", ramdisk_image,
 338                         ramdisk_end);
 339
 340
 341         if (ramdisk_end <= end_of_lowmem) {
 342                 /* All in lowmem, easy case */
 343                 /*
 344                  * don't need to reserve again, already reserved early
 345                  * in i386_start_kernel
 346                  */
 347                 initrd_start = ramdisk_image + PAGE_OFFSET;
 348                 initrd_end = initrd_start + ramdisk_size;
 349                 return;
 350         }
 351
 352 #ifdef CONFIG_X86_32
 353         relocate_initrd();
 354 #else
 355         printk(KERN_ERR "initrd extends beyond end of memory "
 356                "(0x%08llx > 0x%08llx)\ndisabling initrd\n",
 357                ramdisk_end, end_of_lowmem);
 358         initrd_start = 0;
 359 #endif
 360         free_early(ramdisk_image, ramdisk_end);
 361 }
 362 #else
 363 static void __init reserve_initrd(void)
 364 {
 365 }
 366 #endif /* CONFIG_BLK_DEV_INITRD */
 367
 368 /*
 369  * Determine if we were loaded by an EFI loader.  If so, then we have also been
 370  * passed the efi memmap, systab, etc., so we should use these data structures
 371  * for initialization.  Note, the efi init code path is determined by the
 372  * global efi_enabled. This allows the same kernel image to be used on existing
 373  * systems (with a traditional BIOS) as well as on EFI systems.
 374  */
 375 /*
 376  * setup_arch - architecture-specific boot-time initializations
 377  *
 378  * Note: On x86_64, fixmaps are ready for use even before this is called.
 379  */
 380
 381 void __init setup_arch(char **cmdline_p)
 382 {
 383 #ifdef CONFIG_X86_32
 384         memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data));
 385         pre_setup_arch_hook();
 386         early_cpu_init();
 387         early_ioremap_init();
 388         reserve_setup_data();
 389 #else
 390         printk(KERN_INFO "Command line: %s\n", boot_command_line);
 391 #endif
 392
 393         ROOT_DEV = old_decode_dev(boot_params.hdr.root_dev);
 394         screen_info = boot_params.screen_info;
 395         edid_info = boot_params.edid_info;
 396 #ifdef CONFIG_X86_32
 397         apm_info.bios = boot_params.apm_bios_info;
 398         ist_info = boot_params.ist_info;
 399         if (boot_params.sys_desc_table.length != 0) {
 400                 set_mca_bus(boot_params.sys_desc_table.table[3] & 0x2);
 401                 machine_id = boot_params.sys_desc_table.table[0];
 402                 machine_submodel_id = boot_params.sys_desc_table.table[1];
 403                 BIOS_revision = boot_params.sys_desc_table.table[2];
 404         }
 405 #endif
 406         saved_video_mode = boot_params.hdr.vid_mode;
 407         bootloader_type = boot_params.hdr.type_of_loader;
 408
 409 #ifdef CONFIG_BLK_DEV_RAM
 410         rd_image_start = boot_params.hdr.ram_size & RAMDISK_IMAGE_START_MASK;
 411         rd_prompt = ((boot_params.hdr.ram_size & RAMDISK_PROMPT_FLAG) != 0);
 412         rd_doload = ((boot_params.hdr.ram_size & RAMDISK_LOAD_FLAG) != 0);
 413 #endif
 414 #ifdef CONFIG_EFI
 415         if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
 416 #ifdef CONFIG_X86_32
 417                      "EL32",
 418 #else
 419                      "EL64",
 420 #endif
 421          4)) {
 422                 efi_enabled = 1;
 423                 efi_reserve_early();
 424         }
 425 #endif
 426
 427         ARCH_SETUP
 428
 429         setup_memory_map();
 430         copy_edd();
 431
 432         if (!boot_params.hdr.root_flags)
 433                 root_mountflags &= ~MS_RDONLY;
 434         init_mm.start_code = (unsigned long) _text;
 435         init_mm.end_code = (unsigned long) _etext;
 436         init_mm.end_data = (unsigned long) _edata;
 437 #ifdef CONFIG_X86_32
 438         init_mm.brk = init_pg_tables_end + PAGE_OFFSET;
 439 #else
 440         init_mm.brk = (unsigned long) &_end;
 441 #endif
 442
 443         code_resource.start = virt_to_phys(_text);
 444         code_resource.end = virt_to_phys(_etext)-1;
 445         data_resource.start = virt_to_phys(_etext);
 446         data_resource.end = virt_to_phys(_edata)-1;
 447         bss_resource.start = virt_to_phys(&__bss_start);
 448         bss_resource.end = virt_to_phys(&__bss_stop)-1;
 449
 450 #ifdef CONFIG_X86_64
 451         early_cpu_init();
 452 #endif
 453         strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
 454         *cmdline_p = command_line;
 455
 456         parse_setup_data();
 457
 458         parse_early_param();
 459
 460         if (acpi_mps_check()) {
 461 #ifdef CONFIG_X86_LOCAL_APIC
 462 #ifdef CONFIG_X86_32
 463                 enable_local_apic = -1;
 464 #else
 465                 disable_apic = 1;
 466 #endif
 467 #endif
 468                 clear_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
 469         }
 470
 471         finish_e820_parsing();
 472
 473 #ifdef CONFIG_X86_32
 474         probe_roms();
 475 #else
 476 # ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
 477         if (init_ohci1394_dma_early)
 478                 init_ohci1394_dma_on_all_controllers();
 479 # endif
 480 #endif
 481
 482         /* after parse_early_param, so could debug it */
 483         insert_resource(&iomem_resource, &code_resource);
 484         insert_resource(&iomem_resource, &data_resource);
 485         insert_resource(&iomem_resource, &bss_resource);
 486
 487         if (efi_enabled)
 488                 efi_init();
 489
 490 #ifdef CONFIG_X86_32
 491         if (ppro_with_ram_bug()) {
 492                 e820_update_range(0x70000000ULL, 0x40000ULL, E820_RAM,
 493                                   E820_RESERVED);
 494                 sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
 495                 printk(KERN_INFO "fixed physical RAM map:\n");
 496                 e820_print_map("bad_ppro");
 497         }
 498 #else
 499         early_gart_iommu_check();
 500 #endif
 501
 502         e820_register_active_regions(0, 0, -1UL);
 503         /*
 504          * partially used pages are not usable - thus
 505          * we are rounding upwards:
 506          */
 507         max_pfn = e820_end_of_ram();
 508
 509         /* preallocate 4k for mptable mpc */
 510         early_reserve_e820_mpc_new();
 511         /* update e820 for memory not covered by WB MTRRs */
 512         mtrr_bp_init();
 513         if (mtrr_trim_uncached_memory(max_pfn)) {
 514                 remove_all_active_ranges();
 515                 e820_register_active_regions(0, 0, -1UL);
 516                 max_pfn = e820_end_of_ram();
 517         }
 518
 519 #ifdef CONFIG_X86_32
 520         /* max_low_pfn get updated here */
 521         find_low_pfn_range();
 522 #else
 523         num_physpages = max_pfn;
 524
 525         check_efer();
 526
 527         /* How many end-of-memory variables you have, grandma! */
 528         /* need this before calling reserve_initrd */
 529         max_low_pfn = max_pfn;
 530         high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
 531 #endif
 532
 533         /* max_pfn_mapped is updated here */
 534 #ifdef CONFIG_X86_64
 535         max_pfn_mapped =
 536 #endif
 537         max_pfn_mapped = init_memory_mapping(0, (max_low_pfn << PAGE_SHIFT));
 538
 539         reserve_initrd();
 540
 541 #ifdef CONFIG_X86_64
 542         vsmp_init();
 543 #endif
 544
 545         dmi_scan_machine();
 546
 547         io_delay_init();
 548
 549         /*
 550          * Parse the ACPI tables for possible boot-time SMP configuration.
 551          */
 552         acpi_boot_table_init();
 553
 554 #ifdef CONFIG_X86_64
 555         /* Remove active ranges so rediscovery with NUMA-awareness happens */
 556         remove_all_active_ranges();
 557 #endif
 558
 559 #ifdef CONFIG_ACPI_NUMA
 560         /*
 561          * Parse SRAT to discover nodes.
 562          */
 563         acpi_numa_init();
 564 #endif
 565
 566         initmem_init(0, max_pfn);
 567
 568 #ifdef CONFIG_X86_64
 569         dma32_reserve_bootmem();
 570 #endif
 571
 572 #ifdef CONFIG_ACPI_SLEEP
 573         /*
 574          * Reserve low memory region for sleep support.
 575          */
 576         acpi_reserve_bootmem();
 577 #endif
 578 #if defined(CONFIG_X86_FIND_SMP_CONFIG) && defined(CONFIG_X86_32) || \
 579     defined(CONFIG_X86_MPPARSE) && defined(CONFIG_X86_64)
 580         /*
 581          * Find and reserve possible boot-time SMP configuration:
 582          */
 583         find_smp_config();
 584 #endif
 585         reserve_crashkernel();
 586
 587         reserve_ibft_region();
 588
 589 #ifdef CONFIG_KVM_CLOCK
 590         kvmclock_init();
 591 #endif
 592
 593 #if defined(CONFIG_VMI) && defined(CONFIG_X86_32)
 594         /*
 595          * Must be after max_low_pfn is determined, and before kernel
 596          * pagetables are setup.
 597          */
 598         vmi_init();
 599 #endif
 600
 601         paging_init();
 602
 603 #ifdef CONFIG_X86_64
 604         map_vsyscall();
 605 #endif
 606
 607         /*
 608          * NOTE: On x86-32, only from this point on, fixmaps are ready for use.
 609          */
 610
 611 #if defined(CONFIG_PROVIDE_OHCI1394_DMA_INIT) && defined(CONFIG_X86_32)
 612         if (init_ohci1394_dma_early)
 613                 init_ohci1394_dma_on_all_controllers();
 614 #endif
 615
 616 #ifdef CONFIG_X86_GENERICARCH
 617         generic_apic_probe();
 618 #endif
 619
 620         early_quirks();
 621
 622         /*
 623          * Read APIC and some other early information from ACPI tables.
 624          */
 625         acpi_boot_init();
 626
 627 #ifdef CONFIG_X86_64
 628         init_cpu_to_node();
 629 #endif
 630
 631 #if defined(CONFIG_X86_MPPARSE) || defined(CONFIG_X86_VISWS)
 632         /*
 633          * get boot-time SMP configuration:
 634          */
 635         if (smp_found_config)
 636                 get_smp_config();
 637 #endif
 638
 639 #ifdef CONFIG_X86_64
 640         init_apic_mappings();
 641         ioapic_init_mappings();
 642 #else
 643 # if defined(CONFIG_SMP) && defined(CONFIG_X86_PC)
 644         if (def_to_bigsmp)
 645                 printk(KERN_WARNING "More than 8 CPUs detected and "
 646                         "CONFIG_X86_PC cannot handle it.\nUse "
 647                         "CONFIG_X86_GENERICARCH or CONFIG_X86_BIGSMP.\n");
 648 # endif
 649 #endif
 650         kvm_guest_init();
 651
 652         e820_reserve_resources();
 653         e820_mark_nosave_regions(max_low_pfn);
 654
 655 #ifdef CONFIG_X86_32
 656         request_resource(&iomem_resource, &video_ram_resource);
 657 #endif
 658         reserve_standard_io_resources();
 659
 660         e820_setup_gap();
 661
 662 #ifdef CONFIG_VT
 663 #if defined(CONFIG_VGA_CONSOLE)
 664         if (!efi_enabled || (efi_mem_type(0xa0000) != EFI_CONVENTIONAL_MEMORY))
 665                 conswitchp = &vga_con;
 666 #elif defined(CONFIG_DUMMY_CONSOLE)
 667         conswitchp = &dummy_con;
 668 #endif
 669 #endif
 670 }
 671