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 # include <asm/realmode.h>
  28 #else
  29 # include <asm/x86_init.h>
  30 #endif
  31
  32 /*
  33  * Power off function, if any
  34  */
  35 void (*pm_power_off)(void);
  36 EXPORT_SYMBOL(pm_power_off);
  37
  38 static const struct desc_ptr no_idt = {};
  39 static int reboot_mode;
  40 enum reboot_type reboot_type = BOOT_ACPI;
  41 int reboot_force;
  42
  43 /* This variable is used privately to keep track of whether or not
  44  * reboot_type is still set to its default value (i.e., reboot= hasn't
  45  * been set on the command line).  This is needed so that we can
  46  * suppress DMI scanning for reboot quirks.  Without it, it's
  47  * impossible to override a faulty reboot quirk without recompiling.
  48  */
  49 static int reboot_default = 1;
  50
  51 #if defined(CONFIG_X86_32) && defined(CONFIG_SMP)
  52 static int reboot_cpu = -1;
  53 #endif
  54
  55 /* This is set if we need to go through the 'emergency' path.
  56  * When machine_emergency_restart() is called, we may be on
  57  * an inconsistent state and won't be able to do a clean cleanup
  58  */
  59 static int reboot_emergency;
  60
  61 /* This is set by the PCI code if either type 1 or type 2 PCI is detected */
  62 bool port_cf9_safe = false;
  63
  64 /* reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old] | p[ci]
  65    warm   Don't set the cold reboot flag
  66    cold   Set the cold reboot flag
  67    bios   Reboot by jumping through the BIOS (only for X86_32)
  68    smp    Reboot by executing reset on BSP or other CPU (only for X86_32)
  69    triple Force a triple fault (init)
  70    kbd    Use the keyboard controller. cold reset (default)
  71    acpi   Use the RESET_REG in the FADT
  72    efi    Use efi reset_system runtime service
  73    pci    Use the so-called "PCI reset register", CF9
  74    force  Avoid anything that could hang.
  75  */
  76 static int __init reboot_setup(char *str)
  77 {
  78         for (;;) {
  79                 /* Having anything passed on the command line via
  80                  * reboot= will cause us to disable DMI checking
  81                  * below.
  82                  */
  83                 reboot_default = 0;
  84
  85                 switch (*str) {
  86                 case 'w':
  87                         reboot_mode = 0x1234;
  88                         break;
  89
  90                 case 'c':
  91                         reboot_mode = 0;
  92                         break;
  93
  94 #ifdef CONFIG_X86_32
  95 #ifdef CONFIG_SMP
  96                 case 's':
  97                         if (isdigit(*(str+1))) {
  98                                 reboot_cpu = (int) (*(str+1) - '0');
  99                                 if (isdigit(*(str+2)))
 100                                         reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0');
 101                         }
 102                                 /* we will leave sorting out the final value
 103                                    when we are ready to reboot, since we might not
 104                                    have detected BSP APIC ID or smp_num_cpu */
 105                         break;
 106 #endif /* CONFIG_SMP */
 107
 108                 case 'b':
 109 #endif
 110                 case 'a':
 111                 case 'k':
 112                 case 't':
 113                 case 'e':
 114                 case 'p':
 115                         reboot_type = *str;
 116                         break;
 117
 118                 case 'f':
 119                         reboot_force = 1;
 120                         break;
 121                 }
 122
 123                 str = strchr(str, ',');
 124                 if (str)
 125                         str++;
 126                 else
 127                         break;
 128         }
 129         return 1;
 130 }
 131
 132 __setup("reboot=", reboot_setup);
 133
 134
 135 #ifdef CONFIG_X86_32
 136 /*
 137  * Reboot options and system auto-detection code provided by
 138  * Dell Inc. so their systems "just work". :-)
 139  */
 140
 141 /*
 142  * Some machines require the "reboot=b" or "reboot=k"  commandline options,
 143  * this quirk makes that automatic.
 144  */
 145 static int __init set_bios_reboot(const struct dmi_system_id *d)
 146 {
 147         if (reboot_type != BOOT_BIOS) {
 148                 reboot_type = BOOT_BIOS;
 149                 printk(KERN_INFO "%s series board detected. Selecting BIOS-method for reboots.\n", d->ident);
 150         }
 151         return 0;
 152 }
 153
 154 static int __init set_kbd_reboot(const struct dmi_system_id *d)
 155 {
 156         if (reboot_type != BOOT_KBD) {
 157                 reboot_type = BOOT_KBD;
 158                 printk(KERN_INFO "%s series board detected. Selecting KBD-method for reboot.\n", d->ident);
 159         }
 160         return 0;
 161 }
 162
 163 static struct dmi_system_id __initdata reboot_dmi_table[] = {
 164         {       /* Handle problems with rebooting on Dell E520's */
 165                 .callback = set_bios_reboot,
 166                 .ident = "Dell E520",
 167                 .matches = {
 168                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 169                         DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
 170                 },
 171         },
 172         {       /* Handle problems with rebooting on Dell 1300's */
 173                 .callback = set_bios_reboot,
 174                 .ident = "Dell PowerEdge 1300",
 175                 .matches = {
 176                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
 177                         DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
 178                 },
 179         },
 180         {       /* Handle problems with rebooting on Dell 300's */
 181                 .callback = set_bios_reboot,
 182                 .ident = "Dell PowerEdge 300",
 183                 .matches = {
 184                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
 185                         DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
 186                 },
 187         },
 188         {       /* Handle problems with rebooting on Dell Optiplex 745's SFF*/
 189                 .callback = set_bios_reboot,
 190                 .ident = "Dell OptiPlex 745",
 191                 .matches = {
 192                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 193                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
 194                 },
 195         },
 196         {       /* Handle problems with rebooting on Dell Optiplex 745's DFF*/
 197                 .callback = set_bios_reboot,
 198                 .ident = "Dell OptiPlex 745",
 199                 .matches = {
 200                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 201                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
 202                         DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
 203                 },
 204         },
 205         {       /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
 206                 .callback = set_bios_reboot,
 207                 .ident = "Dell OptiPlex 745",
 208                 .matches = {
 209                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 210                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
 211                         DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
 212                 },
 213         },
 214         {   /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
 215                 .callback = set_bios_reboot,
 216                 .ident = "Dell OptiPlex 330",
 217                 .matches = {
 218                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 219                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"),
 220                         DMI_MATCH(DMI_BOARD_NAME, "0KP561"),
 221                 },
 222         },
 223         {   /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
 224                 .callback = set_bios_reboot,
 225                 .ident = "Dell OptiPlex 360",
 226                 .matches = {
 227                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 228                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"),
 229                         DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
 230                 },
 231         },
 232         {       /* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G*/
 233                 .callback = set_bios_reboot,
 234                 .ident = "Dell OptiPlex 760",
 235                 .matches = {
 236                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 237                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"),
 238                         DMI_MATCH(DMI_BOARD_NAME, "0G919G"),
 239                 },
 240         },
 241         {       /* Handle problems with rebooting on Dell 2400's */
 242                 .callback = set_bios_reboot,
 243                 .ident = "Dell PowerEdge 2400",
 244                 .matches = {
 245                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
 246                         DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
 247                 },
 248         },
 249         {       /* Handle problems with rebooting on Dell T5400's */
 250                 .callback = set_bios_reboot,
 251                 .ident = "Dell Precision T5400",
 252                 .matches = {
 253                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 254                         DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"),
 255                 },
 256         },
 257         {       /* Handle problems with rebooting on Dell T7400's */
 258                 .callback = set_bios_reboot,
 259                 .ident = "Dell Precision T7400",
 260                 .matches = {
 261                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 262                         DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"),
 263                 },
 264         },
 265         {       /* Handle problems with rebooting on HP laptops */
 266                 .callback = set_bios_reboot,
 267                 .ident = "HP Compaq Laptop",
 268                 .matches = {
 269                         DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 270                         DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
 271                 },
 272         },
 273         {       /* Handle problems with rebooting on Dell XPS710 */
 274                 .callback = set_bios_reboot,
 275                 .ident = "Dell XPS710",
 276                 .matches = {
 277                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 278                         DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
 279                 },
 280         },
 281         {       /* Handle problems with rebooting on Dell DXP061 */
 282                 .callback = set_bios_reboot,
 283                 .ident = "Dell DXP061",
 284                 .matches = {
 285                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 286                         DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"),
 287                 },
 288         },
 289         {       /* Handle problems with rebooting on Sony VGN-Z540N */
 290                 .callback = set_bios_reboot,
 291                 .ident = "Sony VGN-Z540N",
 292                 .matches = {
 293                         DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 294                         DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
 295                 },
 296         },
 297         {       /* Handle problems with rebooting on CompuLab SBC-FITPC2 */
 298                 .callback = set_bios_reboot,
 299                 .ident = "CompuLab SBC-FITPC2",
 300                 .matches = {
 301                         DMI_MATCH(DMI_SYS_VENDOR, "CompuLab"),
 302                         DMI_MATCH(DMI_PRODUCT_NAME, "SBC-FITPC2"),
 303                 },
 304         },
 305         {       /* Handle problems with rebooting on ASUS P4S800 */
 306                 .callback = set_bios_reboot,
 307                 .ident = "ASUS P4S800",
 308                 .matches = {
 309                         DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
 310                         DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
 311                 },
 312         },
 313         { /* Handle reboot issue on Acer Aspire one */
 314                 .callback = set_kbd_reboot,
 315                 .ident = "Acer Aspire One A110",
 316                 .matches = {
 317                         DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
 318                         DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"),
 319                 },
 320         },
 321         { }
 322 };
 323
 324 static int __init reboot_init(void)
 325 {
 326         /* Only do the DMI check if reboot_type hasn't been overridden
 327          * on the command line
 328          */
 329         if (reboot_default) {
 330                 dmi_check_system(reboot_dmi_table);
 331         }
 332         return 0;
 333 }
 334 core_initcall(reboot_init);
 335
 336 void machine_real_restart(unsigned int type)
 337 {
 338         void (*restart_lowmem)(unsigned int) = (void (*)(unsigned int))
 339                 real_mode_header->machine_real_restart_asm;
 340
 341         local_irq_disable();
 342
 343         /* Write zero to CMOS register number 0x0f, which the BIOS POST
 344            routine will recognize as telling it to do a proper reboot.  (Well
 345            that's what this book in front of me says -- it may only apply to
 346            the Phoenix BIOS though, it's not clear).  At the same time,
 347            disable NMIs by setting the top bit in the CMOS address register,
 348            as we're about to do peculiar things to the CPU.  I'm not sure if
 349            `outb_p' is needed instead of just `outb'.  Use it to be on the
 350            safe side.  (Yes, CMOS_WRITE does outb_p's. -  Paul G.)
 351          */
 352         spin_lock(&rtc_lock);
 353         CMOS_WRITE(0x00, 0x8f);
 354         spin_unlock(&rtc_lock);
 355
 356         /*
 357          * Switch back to the initial page table.
 358          */
 359         load_cr3(initial_page_table);
 360
 361         /* Write 0x1234 to absolute memory location 0x472.  The BIOS reads
 362            this on booting to tell it to "Bypass memory test (also warm
 363            boot)".  This seems like a fairly standard thing that gets set by
 364            REBOOT.COM programs, and the previous reset routine did this
 365            too. */
 366         *((unsigned short *)0x472) = reboot_mode;
 367
 368         /* Jump to the identity-mapped low memory code */
 369         restart_lowmem(type);
 370 }
 371 #ifdef CONFIG_APM_MODULE
 372 EXPORT_SYMBOL(machine_real_restart);
 373 #endif
 374
 375 #endif /* CONFIG_X86_32 */
 376
 377 /*
 378  * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
 379  */
 380 static int __init set_pci_reboot(const struct dmi_system_id *d)
 381 {
 382         if (reboot_type != BOOT_CF9) {
 383                 reboot_type = BOOT_CF9;
 384                 printk(KERN_INFO "%s series board detected. "
 385                        "Selecting PCI-method for reboots.\n", d->ident);
 386         }
 387         return 0;
 388 }
 389
 390 static struct dmi_system_id __initdata pci_reboot_dmi_table[] = {
 391         {       /* Handle problems with rebooting on Apple MacBook5 */
 392                 .callback = set_pci_reboot,
 393                 .ident = "Apple MacBook5",
 394                 .matches = {
 395                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 396                         DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"),
 397                 },
 398         },
 399         {       /* Handle problems with rebooting on Apple MacBookPro5 */
 400                 .callback = set_pci_reboot,
 401                 .ident = "Apple MacBookPro5",
 402                 .matches = {
 403                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 404                         DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"),
 405                 },
 406         },
 407         {       /* Handle problems with rebooting on Apple Macmini3,1 */
 408                 .callback = set_pci_reboot,
 409                 .ident = "Apple Macmini3,1",
 410                 .matches = {
 411                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 412                         DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"),
 413                 },
 414         },
 415         {       /* Handle problems with rebooting on the iMac9,1. */
 416                 .callback = set_pci_reboot,
 417                 .ident = "Apple iMac9,1",
 418                 .matches = {
 419                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 420                         DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"),
 421                 },
 422         },
 423         {       /* Handle problems with rebooting on the Latitude E6320. */
 424                 .callback = set_pci_reboot,
 425                 .ident = "Dell Latitude E6320",
 426                 .matches = {
 427                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 428                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6320"),
 429                 },
 430         },
 431         {       /* Handle problems with rebooting on the Latitude E5420. */
 432                 .callback = set_pci_reboot,
 433                 .ident = "Dell Latitude E5420",
 434                 .matches = {
 435                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 436                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5420"),
 437                 },
 438         },
 439         {       /* Handle problems with rebooting on the Latitude E6420. */
 440                 .callback = set_pci_reboot,
 441                 .ident = "Dell Latitude E6420",
 442                 .matches = {
 443                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 444                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6420"),
 445                 },
 446         },
 447         {       /* Handle problems with rebooting on the OptiPlex 990. */
 448                 .callback = set_pci_reboot,
 449                 .ident = "Dell OptiPlex 990",
 450                 .matches = {
 451                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 452                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 990"),
 453                 },
 454         },
 455         { }
 456 };
 457
 458 static int __init pci_reboot_init(void)
 459 {
 460         /* Only do the DMI check if reboot_type hasn't been overridden
 461          * on the command line
 462          */
 463         if (reboot_default) {
 464                 dmi_check_system(pci_reboot_dmi_table);
 465         }
 466         return 0;
 467 }
 468 core_initcall(pci_reboot_init);
 469
 470 static inline void kb_wait(void)
 471 {
 472         int i;
 473
 474         for (i = 0; i < 0x10000; i++) {
 475                 if ((inb(0x64) & 0x02) == 0)
 476                         break;
 477                 udelay(2);
 478         }
 479 }
 480
 481 static void vmxoff_nmi(int cpu, struct pt_regs *regs)
 482 {
 483         cpu_emergency_vmxoff();
 484 }
 485
 486 /* Use NMIs as IPIs to tell all CPUs to disable virtualization
 487  */
 488 static void emergency_vmx_disable_all(void)
 489 {
 490         /* Just make sure we won't change CPUs while doing this */
 491         local_irq_disable();
 492
 493         /* We need to disable VMX on all CPUs before rebooting, otherwise
 494          * we risk hanging up the machine, because the CPU ignore INIT
 495          * signals when VMX is enabled.
 496          *
 497          * We can't take any locks and we may be on an inconsistent
 498          * state, so we use NMIs as IPIs to tell the other CPUs to disable
 499          * VMX and halt.
 500          *
 501          * For safety, we will avoid running the nmi_shootdown_cpus()
 502          * stuff unnecessarily, but we don't have a way to check
 503          * if other CPUs have VMX enabled. So we will call it only if the
 504          * CPU we are running on has VMX enabled.
 505          *
 506          * We will miss cases where VMX is not enabled on all CPUs. This
 507          * shouldn't do much harm because KVM always enable VMX on all
 508          * CPUs anyway. But we can miss it on the small window where KVM
 509          * is still enabling VMX.
 510          */
 511         if (cpu_has_vmx() && cpu_vmx_enabled()) {
 512                 /* Disable VMX on this CPU.
 513                  */
 514                 cpu_vmxoff();
 515
 516                 /* Halt and disable VMX on the other CPUs */
 517                 nmi_shootdown_cpus(vmxoff_nmi);
 518
 519         }
 520 }
 521
 522
 523 void __attribute__((weak)) mach_reboot_fixups(void)
 524 {
 525 }
 526
 527 /*
 528  * Windows compatible x86 hardware expects the following on reboot:
 529  *
 530  * 1) If the FADT has the ACPI reboot register flag set, try it
 531  * 2) If still alive, write to the keyboard controller
 532  * 3) If still alive, write to the ACPI reboot register again
 533  * 4) If still alive, write to the keyboard controller again
 534  *
 535  * If the machine is still alive at this stage, it gives up. We default to
 536  * following the same pattern, except that if we're still alive after (4) we'll
 537  * try to force a triple fault and then cycle between hitting the keyboard
 538  * controller and doing that
 539  */
 540 static void native_machine_emergency_restart(void)
 541 {
 542         int i;
 543         int attempt = 0;
 544         int orig_reboot_type = reboot_type;
 545
 546         if (reboot_emergency)
 547                 emergency_vmx_disable_all();
 548
 549         tboot_shutdown(TB_SHUTDOWN_REBOOT);
 550
 551         /* Tell the BIOS if we want cold or warm reboot */
 552         *((unsigned short *)__va(0x472)) = reboot_mode;
 553
 554         for (;;) {
 555                 /* Could also try the reset bit in the Hammer NB */
 556                 switch (reboot_type) {
 557                 case BOOT_KBD:
 558                         mach_reboot_fixups(); /* for board specific fixups */
 559
 560                         for (i = 0; i < 10; i++) {
 561                                 kb_wait();
 562                                 udelay(50);
 563                                 outb(0xfe, 0x64); /* pulse reset low */
 564                                 udelay(50);
 565                         }
 566                         if (attempt == 0 && orig_reboot_type == BOOT_ACPI) {
 567                                 attempt = 1;
 568                                 reboot_type = BOOT_ACPI;
 569                         } else {
 570                                 reboot_type = BOOT_TRIPLE;
 571                         }
 572                         break;
 573
 574                 case BOOT_TRIPLE:
 575                         load_idt(&no_idt);
 576                         __asm__ __volatile__("int3");
 577
 578                         reboot_type = BOOT_KBD;
 579                         break;
 580
 581 #ifdef CONFIG_X86_32
 582                 case BOOT_BIOS:
 583                         machine_real_restart(MRR_BIOS);
 584
 585                         reboot_type = BOOT_KBD;
 586                         break;
 587 #endif
 588
 589                 case BOOT_ACPI:
 590                         acpi_reboot();
 591                         reboot_type = BOOT_KBD;
 592                         break;
 593
 594                 case BOOT_EFI:
 595                         if (efi_enabled)
 596                                 efi.reset_system(reboot_mode ?
 597                                                  EFI_RESET_WARM :
 598                                                  EFI_RESET_COLD,
 599                                                  EFI_SUCCESS, 0, NULL);
 600                         reboot_type = BOOT_KBD;
 601                         break;
 602
 603                 case BOOT_CF9:
 604                         port_cf9_safe = true;
 605                         /* fall through */
 606
 607                 case BOOT_CF9_COND:
 608                         if (port_cf9_safe) {
 609                                 u8 cf9 = inb(0xcf9) & ~6;
 610                                 outb(cf9|2, 0xcf9); /* Request hard reset */
 611                                 udelay(50);
 612                                 outb(cf9|6, 0xcf9); /* Actually do the reset */
 613                                 udelay(50);
 614                         }
 615                         reboot_type = BOOT_KBD;
 616                         break;
 617                 }
 618         }
 619 }
 620
 621 void native_machine_shutdown(void)
 622 {
 623         /* Stop the cpus and apics */
 624 #ifdef CONFIG_SMP
 625
 626         /* The boot cpu is always logical cpu 0 */
 627         int reboot_cpu_id = 0;
 628
 629 #ifdef CONFIG_X86_32
 630         /* See if there has been given a command line override */
 631         if ((reboot_cpu != -1) && (reboot_cpu < nr_cpu_ids) &&
 632                 cpu_online(reboot_cpu))
 633                 reboot_cpu_id = reboot_cpu;
 634 #endif
 635
 636         /* Make certain the cpu I'm about to reboot on is online */
 637         if (!cpu_online(reboot_cpu_id))
 638                 reboot_cpu_id = smp_processor_id();
 639
 640         /* Make certain I only run on the appropriate processor */
 641         set_cpus_allowed_ptr(current, cpumask_of(reboot_cpu_id));
 642
 643         /* O.K Now that I'm on the appropriate processor,
 644          * stop all of the others.
 645          */
 646         stop_other_cpus();
 647 #endif
 648
 649         lapic_shutdown();
 650
 651 #ifdef CONFIG_X86_IO_APIC
 652         disable_IO_APIC();
 653 #endif
 654
 655 #ifdef CONFIG_HPET_TIMER
 656         hpet_disable();
 657 #endif
 658
 659 #ifdef CONFIG_X86_64
 660         x86_platform.iommu_shutdown();
 661 #endif
 662 }
 663
 664 static void __machine_emergency_restart(int emergency)
 665 {
 666         reboot_emergency = emergency;
 667         machine_ops.emergency_restart();
 668 }
 669
 670 static void native_machine_restart(char *__unused)
 671 {
 672         printk("machine restart\n");
 673
 674         if (!reboot_force)
 675                 machine_shutdown();
 676         __machine_emergency_restart(0);
 677 }
 678
 679 static void native_machine_halt(void)
 680 {
 681         /* stop other cpus and apics */
 682         machine_shutdown();
 683
 684         tboot_shutdown(TB_SHUTDOWN_HALT);
 685
 686         /* stop this cpu */
 687         stop_this_cpu(NULL);
 688 }
 689
 690 static void native_machine_power_off(void)
 691 {
 692         if (pm_power_off) {
 693                 if (!reboot_force)
 694                         machine_shutdown();
 695                 pm_power_off();
 696         }
 697         /* a fallback in case there is no PM info available */
 698         tboot_shutdown(TB_SHUTDOWN_HALT);
 699 }
 700
 701 struct machine_ops machine_ops = {
 702         .power_off = native_machine_power_off,
 703         .shutdown = native_machine_shutdown,
 704         .emergency_restart = native_machine_emergency_restart,
 705         .restart = native_machine_restart,
 706         .halt = native_machine_halt,
 707 #ifdef CONFIG_KEXEC
 708         .crash_shutdown = native_machine_crash_shutdown,
 709 #endif
 710 };
 711
 712 void machine_power_off(void)
 713 {
 714         machine_ops.power_off();
 715 }
 716
 717 void machine_shutdown(void)
 718 {
 719         machine_ops.shutdown();
 720 }
 721
 722 void machine_emergency_restart(void)
 723 {
 724         __machine_emergency_restart(1);
 725 }
 726
 727 void machine_restart(char *cmd)
 728 {
 729         machine_ops.restart(cmd);
 730 }
 731
 732 void machine_halt(void)
 733 {
 734         machine_ops.halt();
 735 }
 736
 737 #ifdef CONFIG_KEXEC
 738 void machine_crash_shutdown(struct pt_regs *regs)
 739 {
 740         machine_ops.crash_shutdown(regs);
 741 }
 742 #endif
 743
 744
 745 #if defined(CONFIG_SMP)
 746
 747 /* This keeps a track of which one is crashing cpu. */
 748 static int crashing_cpu;
 749 static nmi_shootdown_cb shootdown_callback;
 750
 751 static atomic_t waiting_for_crash_ipi;
 752
 753 static int crash_nmi_callback(unsigned int val, struct pt_regs *regs)
 754 {
 755         int cpu;
 756
 757         cpu = raw_smp_processor_id();
 758
 759         /* Don't do anything if this handler is invoked on crashing cpu.
 760          * Otherwise, system will completely hang. Crashing cpu can get
 761          * an NMI if system was initially booted with nmi_watchdog parameter.
 762          */
 763         if (cpu == crashing_cpu)
 764                 return NMI_HANDLED;
 765         local_irq_disable();
 766
 767         shootdown_callback(cpu, regs);
 768
 769         atomic_dec(&waiting_for_crash_ipi);
 770         /* Assume hlt works */
 771         halt();
 772         for (;;)
 773                 cpu_relax();
 774
 775         return NMI_HANDLED;
 776 }
 777
 778 static void smp_send_nmi_allbutself(void)
 779 {
 780         apic->send_IPI_allbutself(NMI_VECTOR);
 781 }
 782
 783 /* Halt all other CPUs, calling the specified function on each of them
 784  *
 785  * This function can be used to halt all other CPUs on crash
 786  * or emergency reboot time. The function passed as parameter
 787  * will be called inside a NMI handler on all CPUs.
 788  */
 789 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
 790 {
 791         unsigned long msecs;
 792         local_irq_disable();
 793
 794         /* Make a note of crashing cpu. Will be used in NMI callback.*/
 795         crashing_cpu = safe_smp_processor_id();
 796
 797         shootdown_callback = callback;
 798
 799         atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
 800         /* Would it be better to replace the trap vector here? */
 801         if (register_nmi_handler(NMI_LOCAL, crash_nmi_callback,
 802                                  NMI_FLAG_FIRST, "crash"))
 803                 return;         /* return what? */
 804         /* Ensure the new callback function is set before sending
 805          * out the NMI
 806          */
 807         wmb();
 808
 809         smp_send_nmi_allbutself();
 810
 811         msecs = 1000; /* Wait at most a second for the other cpus to stop */
 812         while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
 813                 mdelay(1);
 814                 msecs--;
 815         }
 816
 817         /* Leave the nmi callback set */
 818 }
 819 #else /* !CONFIG_SMP */
 820 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
 821 {
 822         /* No other CPUs to shoot down */
 823 }
 824 #endif