arch/x86/kernel/setup.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/efi.h>
  83 #include <asm/sections.h>
  84 #include <asm/dmi.h>
  85 #include <asm/io_apic.h>
  86 #include <asm/ist.h>
  87 #include <asm/vmi.h>
  88 #include <setup_arch.h>
  89 #include <asm/bios_ebda.h>
  90 #include <asm/cacheflush.h>
  91 #include <asm/processor.h>
  92 #include <asm/bugs.h>
  93
  94 #include <asm/system.h>
  95 #include <asm/vsyscall.h>
  96 #include <asm/smp.h>
  97 #include <asm/desc.h>
  98 #include <asm/dma.h>
  99 #include <asm/gart.h>
 100 #include <asm/mmu_context.h>
 101 #include <asm/proto.h>
 102
 103 #include <mach_apic.h>
 104 #ifdef CONFIG_PARAVIRT
 105 #include <asm/paravirt.h>
 106 #else
 107 #define ARCH_SETUP
 108 #endif
 109
 110 #include <asm/percpu.h>
 111 #include <asm/sections.h>
 112 #include <asm/topology.h>
 113 #include <asm/apicdef.h>
 114 #ifdef CONFIG_X86_64
 115 #include <asm/numa_64.h>
 116 #endif
 117 #ifdef CONFIG_X86_32
 118 #include <asm/highmem.h>
 119 #endif
 120
 121 /* This value is set up by the early boot code to point to the value
 122    immediately after the boot time page tables.  It contains a *physical*
 123    address, and must not be in the .bss segment! */
 124 unsigned long init_pg_tables_start __initdata = ~0UL;
 125 unsigned long init_pg_tables_end __initdata = ~0UL;
 126
 127 /*
 128  * Machine setup..
 129  */
 130 static struct resource data_resource = {
 131         .name   = "Kernel data",
 132         .start  = 0,
 133         .end    = 0,
 134         .flags  = IORESOURCE_BUSY | IORESOURCE_MEM
 135 };
 136
 137 static struct resource code_resource = {
 138         .name   = "Kernel code",
 139         .start  = 0,
 140         .end    = 0,
 141         .flags  = IORESOURCE_BUSY | IORESOURCE_MEM
 142 };
 143
 144 static struct resource bss_resource = {
 145         .name   = "Kernel bss",
 146         .start  = 0,
 147         .end    = 0,
 148         .flags  = IORESOURCE_BUSY | IORESOURCE_MEM
 149 };
 150
 151
 152 #ifdef CONFIG_X86_32
 153 static struct resource video_ram_resource = {
 154         .name   = "Video RAM area",
 155         .start  = 0xa0000,
 156         .end    = 0xbffff,
 157         .flags  = IORESOURCE_BUSY | IORESOURCE_MEM
 158 };
 159
 160 /* cpu data as detected by the assembly code in head.S */
 161 struct cpuinfo_x86 new_cpu_data __cpuinitdata = {0, 0, 0, 0, -1, 1, 0, 0, -1};
 162 /* common cpu data for all cpus */
 163 struct cpuinfo_x86 boot_cpu_data __read_mostly = {0, 0, 0, 0, -1, 1, 0, 0, -1};
 164 EXPORT_SYMBOL(boot_cpu_data);
 165 static void set_mca_bus(int x)
 166 {
 167 #ifdef CONFIG_MCA
 168         MCA_bus = x;
 169 #endif
 170 }
 171
 172 unsigned int def_to_bigsmp;
 173
 174 /* for MCA, but anyone else can use it if they want */
 175 unsigned int machine_id;
 176 unsigned int machine_submodel_id;
 177 unsigned int BIOS_revision;
 178
 179 struct apm_info apm_info;
 180 EXPORT_SYMBOL(apm_info);
 181
 182 #if defined(CONFIG_X86_SPEEDSTEP_SMI) || \
 183         defined(CONFIG_X86_SPEEDSTEP_SMI_MODULE)
 184 struct ist_info ist_info;
 185 EXPORT_SYMBOL(ist_info);
 186 #else
 187 struct ist_info ist_info;
 188 #endif
 189
 190 #else
 191 struct cpuinfo_x86 boot_cpu_data __read_mostly;
 192 EXPORT_SYMBOL(boot_cpu_data);
 193 #endif
 194
 195
 196 #if !defined(CONFIG_X86_PAE) || defined(CONFIG_X86_64)
 197 unsigned long mmu_cr4_features;
 198 #else
 199 unsigned long mmu_cr4_features = X86_CR4_PAE;
 200 #endif
 201
 202 /* Boot loader ID as an integer, for the benefit of proc_dointvec */
 203 int bootloader_type;
 204
 205 /*
 206  * Early DMI memory
 207  */
 208 int dmi_alloc_index;
 209 char dmi_alloc_data[DMI_MAX_DATA];
 210
 211 /*
 212  * Setup options
 213  */
 214 struct screen_info screen_info;
 215 EXPORT_SYMBOL(screen_info);
 216 struct edid_info edid_info;
 217 EXPORT_SYMBOL_GPL(edid_info);
 218
 219 extern int root_mountflags;
 220
 221 unsigned long saved_video_mode;
 222
 223 #define RAMDISK_IMAGE_START_MASK        0x07FF
 224 #define RAMDISK_PROMPT_FLAG             0x8000
 225 #define RAMDISK_LOAD_FLAG               0x4000
 226
 227 static char __initdata command_line[COMMAND_LINE_SIZE];
 228
 229 #if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE)
 230 struct edd edd;
 231 #ifdef CONFIG_EDD_MODULE
 232 EXPORT_SYMBOL(edd);
 233 #endif
 234 /**
 235  * copy_edd() - Copy the BIOS EDD information
 236  *              from boot_params into a safe place.
 237  *
 238  */
 239 static inline void copy_edd(void)
 240 {
 241      memcpy(edd.mbr_signature, boot_params.edd_mbr_sig_buffer,
 242             sizeof(edd.mbr_signature));
 243      memcpy(edd.edd_info, boot_params.eddbuf, sizeof(edd.edd_info));
 244      edd.mbr_signature_nr = boot_params.edd_mbr_sig_buf_entries;
 245      edd.edd_info_nr = boot_params.eddbuf_entries;
 246 }
 247 #else
 248 static inline void copy_edd(void)
 249 {
 250 }
 251 #endif
 252
 253 #ifdef CONFIG_BLK_DEV_INITRD
 254
 255 #ifdef CONFIG_X86_32
 256
 257 #define MAX_MAP_CHUNK   (NR_FIX_BTMAPS << PAGE_SHIFT)
 258 static void __init relocate_initrd(void)
 259 {
 260
 261         u64 ramdisk_image = boot_params.hdr.ramdisk_image;
 262         u64 ramdisk_size  = boot_params.hdr.ramdisk_size;
 263         u64 end_of_lowmem = max_low_pfn << PAGE_SHIFT;
 264         u64 ramdisk_here;
 265         unsigned long slop, clen, mapaddr;
 266         char *p, *q;
 267
 268         /* We need to move the initrd down into lowmem */
 269         ramdisk_here = find_e820_area(0, end_of_lowmem, ramdisk_size,
 270                                          PAGE_SIZE);
 271
 272         if (ramdisk_here == -1ULL)
 273                 panic("Cannot find place for new RAMDISK of size %lld\n",
 274                          ramdisk_size);
 275
 276         /* Note: this includes all the lowmem currently occupied by
 277            the initrd, we rely on that fact to keep the data intact. */
 278         reserve_early(ramdisk_here, ramdisk_here + ramdisk_size,
 279                          "NEW RAMDISK");
 280         initrd_start = ramdisk_here + PAGE_OFFSET;
 281         initrd_end   = initrd_start + ramdisk_size;
 282         printk(KERN_INFO "Allocated new RAMDISK: %08llx - %08llx\n",
 283                          ramdisk_here, ramdisk_here + ramdisk_size);
 284
 285         q = (char *)initrd_start;
 286
 287         /* Copy any lowmem portion of the initrd */
 288         if (ramdisk_image < end_of_lowmem) {
 289                 clen = end_of_lowmem - ramdisk_image;
 290                 p = (char *)__va(ramdisk_image);
 291                 memcpy(q, p, clen);
 292                 q += clen;
 293                 ramdisk_image += clen;
 294                 ramdisk_size  -= clen;
 295         }
 296
 297         /* Copy the highmem portion of the initrd */
 298         while (ramdisk_size) {
 299                 slop = ramdisk_image & ~PAGE_MASK;
 300                 clen = ramdisk_size;
 301                 if (clen > MAX_MAP_CHUNK-slop)
 302                         clen = MAX_MAP_CHUNK-slop;
 303                 mapaddr = ramdisk_image & PAGE_MASK;
 304                 p = early_ioremap(mapaddr, clen+slop);
 305                 memcpy(q, p+slop, clen);
 306                 early_iounmap(p, clen+slop);
 307                 q += clen;
 308                 ramdisk_image += clen;
 309                 ramdisk_size  -= clen;
 310         }
 311         /* high pages is not converted by early_res_to_bootmem */
 312         ramdisk_image = boot_params.hdr.ramdisk_image;
 313         ramdisk_size  = boot_params.hdr.ramdisk_size;
 314         printk(KERN_INFO "Move RAMDISK from %016llx - %016llx to"
 315                 " %08llx - %08llx\n",
 316                 ramdisk_image, ramdisk_image + ramdisk_size - 1,
 317                 ramdisk_here, ramdisk_here + ramdisk_size - 1);
 318 }
 319 #endif
 320
 321 static void __init reserve_initrd(void)
 322 {
 323         u64 ramdisk_image = boot_params.hdr.ramdisk_image;
 324         u64 ramdisk_size  = boot_params.hdr.ramdisk_size;
 325         u64 ramdisk_end   = ramdisk_image + ramdisk_size;
 326         u64 end_of_lowmem = max_low_pfn << PAGE_SHIFT;
 327
 328         if (!boot_params.hdr.type_of_loader ||
 329             !ramdisk_image || !ramdisk_size)
 330                 return;         /* No initrd provided by bootloader */
 331
 332         initrd_start = 0;
 333
 334         if (ramdisk_size >= (end_of_lowmem>>1)) {
 335                 free_early(ramdisk_image, ramdisk_end);
 336                 printk(KERN_ERR "initrd too large to handle, "
 337                        "disabling initrd\n");
 338                 return;
 339         }
 340
 341         printk(KERN_INFO "RAMDISK: %08llx - %08llx\n", ramdisk_image,
 342                         ramdisk_end);
 343
 344
 345         if (ramdisk_end <= end_of_lowmem) {
 346                 /* All in lowmem, easy case */
 347                 /*
 348                  * don't need to reserve again, already reserved early
 349                  * in i386_start_kernel
 350                  */
 351                 initrd_start = ramdisk_image + PAGE_OFFSET;
 352                 initrd_end = initrd_start + ramdisk_size;
 353                 return;
 354         }
 355
 356 #ifdef CONFIG_X86_32
 357         relocate_initrd();
 358 #else
 359         printk(KERN_ERR "initrd extends beyond end of memory "
 360                "(0x%08llx > 0x%08llx)\ndisabling initrd\n",
 361                ramdisk_end, end_of_lowmem);
 362         initrd_start = 0;
 363 #endif
 364         free_early(ramdisk_image, ramdisk_end);
 365 }
 366 #else
 367 static void __init reserve_initrd(void)
 368 {
 369 }
 370 #endif /* CONFIG_BLK_DEV_INITRD */
 371
 372 /*
 373  * Determine if we were loaded by an EFI loader.  If so, then we have also been
 374  * passed the efi memmap, systab, etc., so we should use these data structures
 375  * for initialization.  Note, the efi init code path is determined by the
 376  * global efi_enabled. This allows the same kernel image to be used on existing
 377  * systems (with a traditional BIOS) as well as on EFI systems.
 378  */
 379 /*
 380  * setup_arch - architecture-specific boot-time initializations
 381  *
 382  * Note: On x86_64, fixmaps are ready for use even before this is called.
 383  */
 384
 385 void __init setup_arch(char **cmdline_p)
 386 {
 387 #ifdef CONFIG_X86_32
 388         memcpy(&boot_cpu_data, &new_cpu_data, sizeof(new_cpu_data));
 389         pre_setup_arch_hook();
 390         early_cpu_init();
 391         early_ioremap_init();
 392         reserve_setup_data();
 393 #else
 394         printk(KERN_INFO "Command line: %s\n", boot_command_line);
 395 #endif
 396
 397         ROOT_DEV = old_decode_dev(boot_params.hdr.root_dev);
 398         screen_info = boot_params.screen_info;
 399         edid_info = boot_params.edid_info;
 400 #ifdef CONFIG_X86_32
 401         apm_info.bios = boot_params.apm_bios_info;
 402         ist_info = boot_params.ist_info;
 403         if (boot_params.sys_desc_table.length != 0) {
 404                 set_mca_bus(boot_params.sys_desc_table.table[3] & 0x2);
 405                 machine_id = boot_params.sys_desc_table.table[0];
 406                 machine_submodel_id = boot_params.sys_desc_table.table[1];
 407                 BIOS_revision = boot_params.sys_desc_table.table[2];
 408         }
 409 #endif
 410         saved_video_mode = boot_params.hdr.vid_mode;
 411         bootloader_type = boot_params.hdr.type_of_loader;
 412
 413 #ifdef CONFIG_BLK_DEV_RAM
 414         rd_image_start = boot_params.hdr.ram_size & RAMDISK_IMAGE_START_MASK;
 415         rd_prompt = ((boot_params.hdr.ram_size & RAMDISK_PROMPT_FLAG) != 0);
 416         rd_doload = ((boot_params.hdr.ram_size & RAMDISK_LOAD_FLAG) != 0);
 417 #endif
 418 #ifdef CONFIG_EFI
 419         if (!strncmp((char *)&boot_params.efi_info.efi_loader_signature,
 420 #ifdef CONFIG_X86_32
 421                      "EL32",
 422 #else
 423                      "EL64",
 424 #endif
 425          4)) {
 426                 efi_enabled = 1;
 427                 efi_reserve_early();
 428         }
 429 #endif
 430
 431         ARCH_SETUP
 432
 433         setup_memory_map();
 434         copy_edd();
 435
 436         if (!boot_params.hdr.root_flags)
 437                 root_mountflags &= ~MS_RDONLY;
 438         init_mm.start_code = (unsigned long) _text;
 439         init_mm.end_code = (unsigned long) _etext;
 440         init_mm.end_data = (unsigned long) _edata;
 441 #ifdef CONFIG_X86_32
 442         init_mm.brk = init_pg_tables_end + PAGE_OFFSET;
 443 #else
 444         init_mm.brk = (unsigned long) &_end;
 445 #endif
 446
 447         code_resource.start = virt_to_phys(_text);
 448         code_resource.end = virt_to_phys(_etext)-1;
 449         data_resource.start = virt_to_phys(_etext);
 450         data_resource.end = virt_to_phys(_edata)-1;
 451         bss_resource.start = virt_to_phys(&__bss_start);
 452         bss_resource.end = virt_to_phys(&__bss_stop)-1;
 453
 454 #ifdef CONFIG_X86_64
 455         early_cpu_init();
 456 #endif
 457         strlcpy(command_line, boot_command_line, COMMAND_LINE_SIZE);
 458         *cmdline_p = command_line;
 459
 460         parse_setup_data();
 461
 462         parse_early_param();
 463
 464         if (acpi_mps_check()) {
 465 #ifdef CONFIG_X86_LOCAL_APIC
 466 #ifdef CONFIG_X86_32
 467                 enable_local_apic = -1;
 468 #else
 469                 disable_apic = 1;
 470 #endif
 471 #endif
 472                 clear_cpu_cap(&boot_cpu_data, X86_FEATURE_APIC);
 473         }
 474
 475         finish_e820_parsing();
 476
 477 #ifdef CONFIG_X86_32
 478         probe_roms();
 479 #else
 480 # ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
 481         if (init_ohci1394_dma_early)
 482                 init_ohci1394_dma_on_all_controllers();
 483 # endif
 484 #endif
 485
 486         /* after parse_early_param, so could debug it */
 487         insert_resource(&iomem_resource, &code_resource);
 488         insert_resource(&iomem_resource, &data_resource);
 489         insert_resource(&iomem_resource, &bss_resource);
 490
 491         if (efi_enabled)
 492                 efi_init();
 493
 494 #ifdef CONFIG_X86_32
 495         if (ppro_with_ram_bug()) {
 496                 e820_update_range(0x70000000ULL, 0x40000ULL, E820_RAM,
 497                                   E820_RESERVED);
 498                 sanitize_e820_map(e820.map, ARRAY_SIZE(e820.map), &e820.nr_map);
 499                 printk(KERN_INFO "fixed physical RAM map:\n");
 500                 e820_print_map("bad_ppro");
 501         }
 502 #else
 503         early_gart_iommu_check();
 504 #endif
 505
 506         e820_register_active_regions(0, 0, -1UL);
 507         /*
 508          * partially used pages are not usable - thus
 509          * we are rounding upwards:
 510          */
 511         max_pfn = e820_end_of_ram();
 512
 513         /* preallocate 4k for mptable mpc */
 514         early_reserve_e820_mpc_new();
 515         /* update e820 for memory not covered by WB MTRRs */
 516         mtrr_bp_init();
 517         if (mtrr_trim_uncached_memory(max_pfn)) {
 518                 remove_all_active_ranges();
 519                 e820_register_active_regions(0, 0, -1UL);
 520                 max_pfn = e820_end_of_ram();
 521         }
 522
 523 #ifdef CONFIG_X86_32
 524         /* max_low_pfn get updated here */
 525         find_low_pfn_range();
 526 #else
 527         num_physpages = max_pfn;
 528
 529         check_efer();
 530
 531         /* How many end-of-memory variables you have, grandma! */
 532         /* need this before calling reserve_initrd */
 533         max_low_pfn = max_pfn;
 534         high_memory = (void *)__va(max_pfn * PAGE_SIZE - 1) + 1;
 535 #endif
 536
 537         /* max_pfn_mapped is updated here */
 538         max_pfn_mapped = init_memory_mapping(0, (max_low_pfn << PAGE_SHIFT));
 539
 540         reserve_initrd();
 541
 542 #ifdef CONFIG_X86_64
 543         vsmp_init();
 544 #endif
 545
 546         dmi_scan_machine();
 547
 548         io_delay_init();
 549
 550         /*
 551          * Parse the ACPI tables for possible boot-time SMP configuration.
 552          */
 553         acpi_boot_table_init();
 554
 555 #ifdef CONFIG_X86_64
 556         /* Remove active ranges so rediscovery with NUMA-awareness happens */
 557         remove_all_active_ranges();
 558 #endif
 559
 560 #ifdef CONFIG_ACPI_NUMA
 561         /*
 562          * Parse SRAT to discover nodes.
 563          */
 564         acpi_numa_init();
 565 #endif
 566
 567         initmem_init(0, max_pfn);
 568
 569 #ifdef CONFIG_X86_64
 570         dma32_reserve_bootmem();
 571 #endif
 572
 573 #ifdef CONFIG_ACPI_SLEEP
 574         /*
 575          * Reserve low memory region for sleep support.
 576          */
 577         acpi_reserve_bootmem();
 578 #endif
 579 #if defined(CONFIG_X86_FIND_SMP_CONFIG) && defined(CONFIG_X86_32) || \
 580     defined(CONFIG_X86_MPPARSE) && defined(CONFIG_X86_64)
 581         /*
 582          * Find and reserve possible boot-time SMP configuration:
 583          */
 584         find_smp_config();
 585 #endif
 586         reserve_crashkernel();
 587
 588         reserve_ibft_region();
 589
 590 #ifdef CONFIG_KVM_CLOCK
 591         kvmclock_init();
 592 #endif
 593
 594 #if defined(CONFIG_VMI) && defined(CONFIG_X86_32)
 595         /*
 596          * Must be after max_low_pfn is determined, and before kernel
 597          * pagetables are setup.
 598          */
 599         vmi_init();
 600 #endif
 601
 602         paging_init();
 603
 604 #ifdef CONFIG_X86_64
 605         map_vsyscall();
 606 #endif
 607
 608         /*
 609          * NOTE: On x86-32, only from this point on, fixmaps are ready for use.
 610          */
 611
 612 #if defined(CONFIG_PROVIDE_OHCI1394_DMA_INIT) && defined(CONFIG_X86_32)
 613         if (init_ohci1394_dma_early)
 614                 init_ohci1394_dma_on_all_controllers();
 615 #endif
 616
 617 #ifdef CONFIG_X86_GENERICARCH
 618         generic_apic_probe();
 619 #endif
 620
 621         early_quirks();
 622
 623         /*
 624          * Read APIC and some other early information from ACPI tables.
 625          */
 626         acpi_boot_init();
 627
 628 #ifdef CONFIG_X86_64
 629         init_cpu_to_node();
 630 #endif
 631
 632 #if defined(CONFIG_X86_MPPARSE) || defined(CONFIG_X86_VISWS)
 633         /*
 634          * get boot-time SMP configuration:
 635          */
 636         if (smp_found_config)
 637                 get_smp_config();
 638 #endif
 639
 640 #ifdef CONFIG_X86_64
 641         init_apic_mappings();
 642         ioapic_init_mappings();
 643 #else
 644 # if defined(CONFIG_SMP) && defined(CONFIG_X86_PC)
 645         if (def_to_bigsmp)
 646                 printk(KERN_WARNING "More than 8 CPUs detected and "
 647                         "CONFIG_X86_PC cannot handle it.\nUse "
 648                         "CONFIG_X86_GENERICARCH or CONFIG_X86_BIGSMP.\n");
 649 # endif
 650 #endif
 651         kvm_guest_init();
 652
 653         e820_reserve_resources();
 654         e820_mark_nosave_regions(max_low_pfn);
 655
 656 #ifdef CONFIG_X86_32
 657         request_resource(&iomem_resource, &video_ram_resource);
 658 #endif
 659         reserve_standard_io_resources();
 660
 661         e820_setup_gap();
 662
 663 #ifdef CONFIG_VT
 664 #if defined(CONFIG_VGA_CONSOLE)
 665         if (!efi_enabled || (efi_mem_type(0xa0000) != EFI_CONVENTIONAL_MEMORY))
 666                 conswitchp = &vga_con;
 667 #elif defined(CONFIG_DUMMY_CONSOLE)
 668         conswitchp = &dummy_con;
 669 #endif
 670 #endif
 671 }
 672