arch/x86/kernel/reboot.c

   1 #include <linux/module.h>
   2 #include <linux/reboot.h>
   3 #include <linux/init.h>
   4 #include <linux/pm.h>
   5 #include <linux/efi.h>
   6 #include <linux/dmi.h>
   7 #include <linux/sched.h>
   8 #include <linux/tboot.h>
   9 #include <linux/delay.h>
  10 #include <acpi/reboot.h>
  11 #include <asm/io.h>
  12 #include <asm/apic.h>
  13 #include <asm/desc.h>
  14 #include <asm/hpet.h>
  15 #include <asm/pgtable.h>
  16 #include <asm/proto.h>
  17 #include <asm/reboot_fixups.h>
  18 #include <asm/reboot.h>
  19 #include <asm/pci_x86.h>
  20 #include <asm/virtext.h>
  21 #include <asm/cpu.h>
  22 #include <asm/nmi.h>
  23
  24 #ifdef CONFIG_X86_32
  25 # include <linux/ctype.h>
  26 # include <linux/mc146818rtc.h>
  27 #else
  28 # include <asm/x86_init.h>
  29 #endif
  30
  31 /*
  32  * Power off function, if any
  33  */
  34 void (*pm_power_off)(void);
  35 EXPORT_SYMBOL(pm_power_off);
  36
  37 static const struct desc_ptr no_idt = {};
  38 static int reboot_mode;
  39 enum reboot_type reboot_type = BOOT_ACPI;
  40 int reboot_force;
  41
  42 #if defined(CONFIG_X86_32) && defined(CONFIG_SMP)
  43 static int reboot_cpu = -1;
  44 #endif
  45
  46 /* This is set if we need to go through the 'emergency' path.
  47  * When machine_emergency_restart() is called, we may be on
  48  * an inconsistent state and won't be able to do a clean cleanup
  49  */
  50 static int reboot_emergency;
  51
  52 /* This is set by the PCI code if either type 1 or type 2 PCI is detected */
  53 bool port_cf9_safe = false;
  54
  55 /* reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old] | p[ci]
  56    warm   Don't set the cold reboot flag
  57    cold   Set the cold reboot flag
  58    bios   Reboot by jumping through the BIOS (only for X86_32)
  59    smp    Reboot by executing reset on BSP or other CPU (only for X86_32)
  60    triple Force a triple fault (init)
  61    kbd    Use the keyboard controller. cold reset (default)
  62    acpi   Use the RESET_REG in the FADT
  63    efi    Use efi reset_system runtime service
  64    pci    Use the so-called "PCI reset register", CF9
  65    force  Avoid anything that could hang.
  66  */
  67 static int __init reboot_setup(char *str)
  68 {
  69         for (;;) {
  70                 switch (*str) {
  71                 case 'w':
  72                         reboot_mode = 0x1234;
  73                         break;
  74
  75                 case 'c':
  76                         reboot_mode = 0;
  77                         break;
  78
  79 #ifdef CONFIG_X86_32
  80 #ifdef CONFIG_SMP
  81                 case 's':
  82                         if (isdigit(*(str+1))) {
  83                                 reboot_cpu = (int) (*(str+1) - '0');
  84                                 if (isdigit(*(str+2)))
  85                                         reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0');
  86                         }
  87                                 /* we will leave sorting out the final value
  88                                    when we are ready to reboot, since we might not
  89                                    have detected BSP APIC ID or smp_num_cpu */
  90                         break;
  91 #endif /* CONFIG_SMP */
  92
  93                 case 'b':
  94 #endif
  95                 case 'a':
  96                 case 'k':
  97                 case 't':
  98                 case 'e':
  99                 case 'p':
 100                         reboot_type = *str;
 101                         break;
 102
 103                 case 'f':
 104                         reboot_force = 1;
 105                         break;
 106                 }
 107
 108                 str = strchr(str, ',');
 109                 if (str)
 110                         str++;
 111                 else
 112                         break;
 113         }
 114         return 1;
 115 }
 116
 117 __setup("reboot=", reboot_setup);
 118
 119
 120 #ifdef CONFIG_X86_32
 121 /*
 122  * Reboot options and system auto-detection code provided by
 123  * Dell Inc. so their systems "just work". :-)
 124  */
 125
 126 /*
 127  * Some machines require the "reboot=b"  commandline option,
 128  * this quirk makes that automatic.
 129  */
 130 static int __init set_bios_reboot(const struct dmi_system_id *d)
 131 {
 132         if (reboot_type != BOOT_BIOS) {
 133                 reboot_type = BOOT_BIOS;
 134                 printk(KERN_INFO "%s series board detected. Selecting BIOS-method for reboots.\n", d->ident);
 135         }
 136         return 0;
 137 }
 138
 139 static struct dmi_system_id __initdata reboot_dmi_table[] = {
 140         {       /* Handle problems with rebooting on Dell E520's */
 141                 .callback = set_bios_reboot,
 142                 .ident = "Dell E520",
 143                 .matches = {
 144                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 145                         DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
 146                 },
 147         },
 148         {       /* Handle problems with rebooting on Dell 1300's */
 149                 .callback = set_bios_reboot,
 150                 .ident = "Dell PowerEdge 1300",
 151                 .matches = {
 152                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
 153                         DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
 154                 },
 155         },
 156         {       /* Handle problems with rebooting on Dell 300's */
 157                 .callback = set_bios_reboot,
 158                 .ident = "Dell PowerEdge 300",
 159                 .matches = {
 160                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
 161                         DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
 162                 },
 163         },
 164         {       /* Handle problems with rebooting on Dell Optiplex 745's SFF*/
 165                 .callback = set_bios_reboot,
 166                 .ident = "Dell OptiPlex 745",
 167                 .matches = {
 168                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 169                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
 170                 },
 171         },
 172         {       /* Handle problems with rebooting on Dell Optiplex 745's DFF*/
 173                 .callback = set_bios_reboot,
 174                 .ident = "Dell OptiPlex 745",
 175                 .matches = {
 176                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 177                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
 178                         DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
 179                 },
 180         },
 181         {       /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
 182                 .callback = set_bios_reboot,
 183                 .ident = "Dell OptiPlex 745",
 184                 .matches = {
 185                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 186                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
 187                         DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
 188                 },
 189         },
 190         {   /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
 191                 .callback = set_bios_reboot,
 192                 .ident = "Dell OptiPlex 330",
 193                 .matches = {
 194                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 195                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"),
 196                         DMI_MATCH(DMI_BOARD_NAME, "0KP561"),
 197                 },
 198         },
 199         {   /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
 200                 .callback = set_bios_reboot,
 201                 .ident = "Dell OptiPlex 360",
 202                 .matches = {
 203                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 204                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"),
 205                         DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
 206                 },
 207         },
 208         {       /* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G*/
 209                 .callback = set_bios_reboot,
 210                 .ident = "Dell OptiPlex 760",
 211                 .matches = {
 212                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 213                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"),
 214                         DMI_MATCH(DMI_BOARD_NAME, "0G919G"),
 215                 },
 216         },
 217         {       /* Handle problems with rebooting on Dell 2400's */
 218                 .callback = set_bios_reboot,
 219                 .ident = "Dell PowerEdge 2400",
 220                 .matches = {
 221                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
 222                         DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
 223                 },
 224         },
 225         {       /* Handle problems with rebooting on Dell T5400's */
 226                 .callback = set_bios_reboot,
 227                 .ident = "Dell Precision T5400",
 228                 .matches = {
 229                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 230                         DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"),
 231                 },
 232         },
 233         {       /* Handle problems with rebooting on Dell T7400's */
 234                 .callback = set_bios_reboot,
 235                 .ident = "Dell Precision T7400",
 236                 .matches = {
 237                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 238                         DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"),
 239                 },
 240         },
 241         {       /* Handle problems with rebooting on HP laptops */
 242                 .callback = set_bios_reboot,
 243                 .ident = "HP Compaq Laptop",
 244                 .matches = {
 245                         DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 246                         DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
 247                 },
 248         },
 249         {       /* Handle problems with rebooting on Dell XPS710 */
 250                 .callback = set_bios_reboot,
 251                 .ident = "Dell XPS710",
 252                 .matches = {
 253                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 254                         DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
 255                 },
 256         },
 257         {       /* Handle problems with rebooting on Dell DXP061 */
 258                 .callback = set_bios_reboot,
 259                 .ident = "Dell DXP061",
 260                 .matches = {
 261                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 262                         DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"),
 263                 },
 264         },
 265         {       /* Handle problems with rebooting on Sony VGN-Z540N */
 266                 .callback = set_bios_reboot,
 267                 .ident = "Sony VGN-Z540N",
 268                 .matches = {
 269                         DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 270                         DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
 271                 },
 272         },
 273         {       /* Handle problems with rebooting on CompuLab SBC-FITPC2 */
 274                 .callback = set_bios_reboot,
 275                 .ident = "CompuLab SBC-FITPC2",
 276                 .matches = {
 277                         DMI_MATCH(DMI_SYS_VENDOR, "CompuLab"),
 278                         DMI_MATCH(DMI_PRODUCT_NAME, "SBC-FITPC2"),
 279                 },
 280         },
 281         {       /* Handle problems with rebooting on ASUS P4S800 */
 282                 .callback = set_bios_reboot,
 283                 .ident = "ASUS P4S800",
 284                 .matches = {
 285                         DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
 286                         DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
 287                 },
 288         },
 289         {       /* Handle problems with rebooting on VersaLogic Menlow boards */
 290                 .callback = set_bios_reboot,
 291                 .ident = "VersaLogic Menlow based board",
 292                 .matches = {
 293                         DMI_MATCH(DMI_BOARD_VENDOR, "VersaLogic Corporation"),
 294                         DMI_MATCH(DMI_BOARD_NAME, "VersaLogic Menlow board"),
 295                 },
 296         },
 297         { /* Handle reboot issue on Acer Aspire one */
 298                 .callback = set_bios_reboot,
 299                 .ident = "Acer Aspire One A110",
 300                 .matches = {
 301                         DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
 302                         DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"),
 303                 },
 304         },
 305         { }
 306 };
 307
 308 static int __init reboot_init(void)
 309 {
 310         dmi_check_system(reboot_dmi_table);
 311         return 0;
 312 }
 313 core_initcall(reboot_init);
 314
 315 extern const unsigned char machine_real_restart_asm[];
 316 extern const u64 machine_real_restart_gdt[3];
 317
 318 void machine_real_restart(unsigned int type)
 319 {
 320         void *restart_va;
 321         unsigned long restart_pa;
 322         void (*restart_lowmem)(unsigned int);
 323         u64 *lowmem_gdt;
 324
 325         local_irq_disable();
 326
 327         /* Write zero to CMOS register number 0x0f, which the BIOS POST
 328            routine will recognize as telling it to do a proper reboot.  (Well
 329            that's what this book in front of me says -- it may only apply to
 330            the Phoenix BIOS though, it's not clear).  At the same time,
 331            disable NMIs by setting the top bit in the CMOS address register,
 332            as we're about to do peculiar things to the CPU.  I'm not sure if
 333            `outb_p' is needed instead of just `outb'.  Use it to be on the
 334            safe side.  (Yes, CMOS_WRITE does outb_p's. -  Paul G.)
 335          */
 336         spin_lock(&rtc_lock);
 337         CMOS_WRITE(0x00, 0x8f);
 338         spin_unlock(&rtc_lock);
 339
 340         /*
 341          * Switch back to the initial page table.
 342          */
 343         load_cr3(initial_page_table);
 344
 345         /* Write 0x1234 to absolute memory location 0x472.  The BIOS reads
 346            this on booting to tell it to "Bypass memory test (also warm
 347            boot)".  This seems like a fairly standard thing that gets set by
 348            REBOOT.COM programs, and the previous reset routine did this
 349            too. */
 350         *((unsigned short *)0x472) = reboot_mode;
 351
 352         /* Patch the GDT in the low memory trampoline */
 353         lowmem_gdt = TRAMPOLINE_SYM(machine_real_restart_gdt);
 354
 355         restart_va = TRAMPOLINE_SYM(machine_real_restart_asm);
 356         restart_pa = virt_to_phys(restart_va);
 357         restart_lowmem = (void (*)(unsigned int))restart_pa;
 358
 359         /* GDT[0]: GDT self-pointer */
 360         lowmem_gdt[0] =
 361                 (u64)(sizeof(machine_real_restart_gdt) - 1) +
 362                 ((u64)virt_to_phys(lowmem_gdt) << 16);
 363         /* GDT[1]: 64K real mode code segment */
 364         lowmem_gdt[1] =
 365                 GDT_ENTRY(0x009b, restart_pa, 0xffff);
 366
 367         /* Jump to the identity-mapped low memory code */
 368         restart_lowmem(type);
 369 }
 370 #ifdef CONFIG_APM_MODULE
 371 EXPORT_SYMBOL(machine_real_restart);
 372 #endif
 373
 374 #endif /* CONFIG_X86_32 */
 375
 376 /*
 377  * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
 378  */
 379 static int __init set_pci_reboot(const struct dmi_system_id *d)
 380 {
 381         if (reboot_type != BOOT_CF9) {
 382                 reboot_type = BOOT_CF9;
 383                 printk(KERN_INFO "%s series board detected. "
 384                        "Selecting PCI-method for reboots.\n", d->ident);
 385         }
 386         return 0;
 387 }
 388
 389 static struct dmi_system_id __initdata pci_reboot_dmi_table[] = {
 390         {       /* Handle problems with rebooting on Apple MacBook5 */
 391                 .callback = set_pci_reboot,
 392                 .ident = "Apple MacBook5",
 393                 .matches = {
 394                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 395                         DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"),
 396                 },
 397         },
 398         {       /* Handle problems with rebooting on Apple MacBookPro5 */
 399                 .callback = set_pci_reboot,
 400                 .ident = "Apple MacBookPro5",
 401                 .matches = {
 402                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 403                         DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"),
 404                 },
 405         },
 406         {       /* Handle problems with rebooting on Apple Macmini3,1 */
 407                 .callback = set_pci_reboot,
 408                 .ident = "Apple Macmini3,1",
 409                 .matches = {
 410                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 411                         DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"),
 412                 },
 413         },
 414         {       /* Handle problems with rebooting on the iMac9,1. */
 415                 .callback = set_pci_reboot,
 416                 .ident = "Apple iMac9,1",
 417                 .matches = {
 418                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 419                         DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"),
 420                 },
 421         },
 422         {       /* Handle problems with rebooting on the Latitude E6320. */
 423                 .callback = set_pci_reboot,
 424                 .ident = "Dell Latitude E6320",
 425                 .matches = {
 426                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 427                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6320"),
 428                 },
 429         },
 430         {       /* Handle problems with rebooting on the Latitude E5420. */
 431                 .callback = set_pci_reboot,
 432                 .ident = "Dell Latitude E5420",
 433                 .matches = {
 434                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 435                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5420"),
 436                 },
 437         },
 438         {       /* Handle problems with rebooting on the Latitude E6420. */
 439                 .callback = set_pci_reboot,
 440                 .ident = "Dell Latitude E6420",
 441                 .matches = {
 442                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 443                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6420"),
 444                 },
 445         },
 446         { }
 447 };
 448
 449 static int __init pci_reboot_init(void)
 450 {
 451         dmi_check_system(pci_reboot_dmi_table);
 452         return 0;
 453 }
 454 core_initcall(pci_reboot_init);
 455
 456 static inline void kb_wait(void)
 457 {
 458         int i;
 459
 460         for (i = 0; i < 0x10000; i++) {
 461                 if ((inb(0x64) & 0x02) == 0)
 462                         break;
 463                 udelay(2);
 464         }
 465 }
 466
 467 static void vmxoff_nmi(int cpu, struct die_args *args)
 468 {
 469         cpu_emergency_vmxoff();
 470 }
 471
 472 /* Use NMIs as IPIs to tell all CPUs to disable virtualization
 473  */
 474 static void emergency_vmx_disable_all(void)
 475 {
 476         /* Just make sure we won't change CPUs while doing this */
 477         local_irq_disable();
 478
 479         /* We need to disable VMX on all CPUs before rebooting, otherwise
 480          * we risk hanging up the machine, because the CPU ignore INIT
 481          * signals when VMX is enabled.
 482          *
 483          * We can't take any locks and we may be on an inconsistent
 484          * state, so we use NMIs as IPIs to tell the other CPUs to disable
 485          * VMX and halt.
 486          *
 487          * For safety, we will avoid running the nmi_shootdown_cpus()
 488          * stuff unnecessarily, but we don't have a way to check
 489          * if other CPUs have VMX enabled. So we will call it only if the
 490          * CPU we are running on has VMX enabled.
 491          *
 492          * We will miss cases where VMX is not enabled on all CPUs. This
 493          * shouldn't do much harm because KVM always enable VMX on all
 494          * CPUs anyway. But we can miss it on the small window where KVM
 495          * is still enabling VMX.
 496          */
 497         if (cpu_has_vmx() && cpu_vmx_enabled()) {
 498                 /* Disable VMX on this CPU.
 499                  */
 500                 cpu_vmxoff();
 501
 502                 /* Halt and disable VMX on the other CPUs */
 503                 nmi_shootdown_cpus(vmxoff_nmi);
 504
 505         }
 506 }
 507
 508
 509 void __attribute__((weak)) mach_reboot_fixups(void)
 510 {
 511 }
 512
 513 /*
 514  * Windows compatible x86 hardware expects the following on reboot:
 515  *
 516  * 1) If the FADT has the ACPI reboot register flag set, try it
 517  * 2) If still alive, write to the keyboard controller
 518  * 3) If still alive, write to the ACPI reboot register again
 519  * 4) If still alive, write to the keyboard controller again
 520  *
 521  * If the machine is still alive at this stage, it gives up. We default to
 522  * following the same pattern, except that if we're still alive after (4) we'll
 523  * try to force a triple fault and then cycle between hitting the keyboard
 524  * controller and doing that
 525  */
 526 static void native_machine_emergency_restart(void)
 527 {
 528         int i;
 529         int attempt = 0;
 530         int orig_reboot_type = reboot_type;
 531
 532         if (reboot_emergency)
 533                 emergency_vmx_disable_all();
 534
 535         tboot_shutdown(TB_SHUTDOWN_REBOOT);
 536
 537         /* Tell the BIOS if we want cold or warm reboot */
 538         *((unsigned short *)__va(0x472)) = reboot_mode;
 539
 540         for (;;) {
 541                 /* Could also try the reset bit in the Hammer NB */
 542                 switch (reboot_type) {
 543                 case BOOT_KBD:
 544                         mach_reboot_fixups(); /* for board specific fixups */
 545
 546                         for (i = 0; i < 10; i++) {
 547                                 kb_wait();
 548                                 udelay(50);
 549                                 outb(0xfe, 0x64); /* pulse reset low */
 550                                 udelay(50);
 551                         }
 552                         if (attempt == 0 && orig_reboot_type == BOOT_ACPI) {
 553                                 attempt = 1;
 554                                 reboot_type = BOOT_ACPI;
 555                         } else {
 556                                 reboot_type = BOOT_TRIPLE;
 557                         }
 558                         break;
 559
 560                 case BOOT_TRIPLE:
 561                         load_idt(&no_idt);
 562                         __asm__ __volatile__("int3");
 563
 564                         reboot_type = BOOT_KBD;
 565                         break;
 566
 567 #ifdef CONFIG_X86_32
 568                 case BOOT_BIOS:
 569                         machine_real_restart(MRR_BIOS);
 570
 571                         reboot_type = BOOT_KBD;
 572                         break;
 573 #endif
 574
 575                 case BOOT_ACPI:
 576                         acpi_reboot();
 577                         reboot_type = BOOT_KBD;
 578                         break;
 579
 580                 case BOOT_EFI:
 581                         if (efi_enabled)
 582                                 efi.reset_system(reboot_mode ?
 583                                                  EFI_RESET_WARM :
 584                                                  EFI_RESET_COLD,
 585                                                  EFI_SUCCESS, 0, NULL);
 586                         reboot_type = BOOT_KBD;
 587                         break;
 588
 589                 case BOOT_CF9:
 590                         port_cf9_safe = true;
 591                         /* fall through */
 592
 593                 case BOOT_CF9_COND:
 594                         if (port_cf9_safe) {
 595                                 u8 cf9 = inb(0xcf9) & ~6;
 596                                 outb(cf9|2, 0xcf9); /* Request hard reset */
 597                                 udelay(50);
 598                                 outb(cf9|6, 0xcf9); /* Actually do the reset */
 599                                 udelay(50);
 600                         }
 601                         reboot_type = BOOT_KBD;
 602                         break;
 603                 }
 604         }
 605 }
 606
 607 void native_machine_shutdown(void)
 608 {
 609         /* Stop the cpus and apics */
 610 #ifdef CONFIG_SMP
 611
 612         /* The boot cpu is always logical cpu 0 */
 613         int reboot_cpu_id = 0;
 614
 615 #ifdef CONFIG_X86_32
 616         /* See if there has been given a command line override */
 617         if ((reboot_cpu != -1) && (reboot_cpu < nr_cpu_ids) &&
 618                 cpu_online(reboot_cpu))
 619                 reboot_cpu_id = reboot_cpu;
 620 #endif
 621
 622         /* Make certain the cpu I'm about to reboot on is online */
 623         if (!cpu_online(reboot_cpu_id))
 624                 reboot_cpu_id = smp_processor_id();
 625
 626         /* Make certain I only run on the appropriate processor */
 627         set_cpus_allowed_ptr(current, cpumask_of(reboot_cpu_id));
 628
 629         /* O.K Now that I'm on the appropriate processor,
 630          * stop all of the others.
 631          */
 632         stop_other_cpus();
 633 #endif
 634
 635         lapic_shutdown();
 636
 637 #ifdef CONFIG_X86_IO_APIC
 638         disable_IO_APIC();
 639 #endif
 640
 641 #ifdef CONFIG_HPET_TIMER
 642         hpet_disable();
 643 #endif
 644
 645 #ifdef CONFIG_X86_64
 646         x86_platform.iommu_shutdown();
 647 #endif
 648 }
 649
 650 static void __machine_emergency_restart(int emergency)
 651 {
 652         reboot_emergency = emergency;
 653         machine_ops.emergency_restart();
 654 }
 655
 656 static void native_machine_restart(char *__unused)
 657 {
 658         printk("machine restart\n");
 659
 660         if (!reboot_force)
 661                 machine_shutdown();
 662         __machine_emergency_restart(0);
 663 }
 664
 665 static void native_machine_halt(void)
 666 {
 667         /* stop other cpus and apics */
 668         machine_shutdown();
 669
 670         tboot_shutdown(TB_SHUTDOWN_HALT);
 671
 672         /* stop this cpu */
 673         stop_this_cpu(NULL);
 674 }
 675
 676 static void native_machine_power_off(void)
 677 {
 678         if (pm_power_off) {
 679                 if (!reboot_force)
 680                         machine_shutdown();
 681                 pm_power_off();
 682         }
 683         /* a fallback in case there is no PM info available */
 684         tboot_shutdown(TB_SHUTDOWN_HALT);
 685 }
 686
 687 struct machine_ops machine_ops = {
 688         .power_off = native_machine_power_off,
 689         .shutdown = native_machine_shutdown,
 690         .emergency_restart = native_machine_emergency_restart,
 691         .restart = native_machine_restart,
 692         .halt = native_machine_halt,
 693 #ifdef CONFIG_KEXEC
 694         .crash_shutdown = native_machine_crash_shutdown,
 695 #endif
 696 };
 697
 698 void machine_power_off(void)
 699 {
 700         machine_ops.power_off();
 701 }
 702
 703 void machine_shutdown(void)
 704 {
 705         machine_ops.shutdown();
 706 }
 707
 708 void machine_emergency_restart(void)
 709 {
 710         __machine_emergency_restart(1);
 711 }
 712
 713 void machine_restart(char *cmd)
 714 {
 715         machine_ops.restart(cmd);
 716 }
 717
 718 void machine_halt(void)
 719 {
 720         machine_ops.halt();
 721 }
 722
 723 #ifdef CONFIG_KEXEC
 724 void machine_crash_shutdown(struct pt_regs *regs)
 725 {
 726         machine_ops.crash_shutdown(regs);
 727 }
 728 #endif
 729
 730
 731 #if defined(CONFIG_SMP)
 732
 733 /* This keeps a track of which one is crashing cpu. */
 734 static int crashing_cpu;
 735 static nmi_shootdown_cb shootdown_callback;
 736
 737 static atomic_t waiting_for_crash_ipi;
 738
 739 static int crash_nmi_callback(struct notifier_block *self,
 740                         unsigned long val, void *data)
 741 {
 742         int cpu;
 743
 744         if (val != DIE_NMI)
 745                 return NOTIFY_OK;
 746
 747         cpu = raw_smp_processor_id();
 748
 749         /* Don't do anything if this handler is invoked on crashing cpu.
 750          * Otherwise, system will completely hang. Crashing cpu can get
 751          * an NMI if system was initially booted with nmi_watchdog parameter.
 752          */
 753         if (cpu == crashing_cpu)
 754                 return NOTIFY_STOP;
 755         local_irq_disable();
 756
 757         shootdown_callback(cpu, (struct die_args *)data);
 758
 759         atomic_dec(&waiting_for_crash_ipi);
 760         /* Assume hlt works */
 761         halt();
 762         for (;;)
 763                 cpu_relax();
 764
 765         return 1;
 766 }
 767
 768 static void smp_send_nmi_allbutself(void)
 769 {
 770         apic->send_IPI_allbutself(NMI_VECTOR);
 771 }
 772
 773 static struct notifier_block crash_nmi_nb = {
 774         .notifier_call = crash_nmi_callback,
 775         /* we want to be the first one called */
 776         .priority = NMI_LOCAL_HIGH_PRIOR+1,
 777 };
 778
 779 /* Halt all other CPUs, calling the specified function on each of them
 780  *
 781  * This function can be used to halt all other CPUs on crash
 782  * or emergency reboot time. The function passed as parameter
 783  * will be called inside a NMI handler on all CPUs.
 784  */
 785 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
 786 {
 787         unsigned long msecs;
 788         local_irq_disable();
 789
 790         /* Make a note of crashing cpu. Will be used in NMI callback.*/
 791         crashing_cpu = safe_smp_processor_id();
 792
 793         shootdown_callback = callback;
 794
 795         atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
 796         /* Would it be better to replace the trap vector here? */
 797         if (register_die_notifier(&crash_nmi_nb))
 798                 return;         /* return what? */
 799         /* Ensure the new callback function is set before sending
 800          * out the NMI
 801          */
 802         wmb();
 803
 804         smp_send_nmi_allbutself();
 805
 806         msecs = 1000; /* Wait at most a second for the other cpus to stop */
 807         while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
 808                 mdelay(1);
 809                 msecs--;
 810         }
 811
 812         /* Leave the nmi callback set */
 813 }
 814 #else /* !CONFIG_SMP */
 815 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
 816 {
 817         /* No other CPUs to shoot down */
 818 }
 819 #endif