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 /* This variable is used privately to keep track of whether or not
  43  * reboot_type is still set to its default value (i.e., reboot= hasn't
  44  * been set on the command line).  This is needed so that we can
  45  * suppress DMI scanning for reboot quirks.  Without it, it's
  46  * impossible to override a faulty reboot quirk without recompiling.
  47  */
  48 static int reboot_default = 1;
  49
  50 #if defined(CONFIG_X86_32) && defined(CONFIG_SMP)
  51 static int reboot_cpu = -1;
  52 #endif
  53
  54 /* This is set if we need to go through the 'emergency' path.
  55  * When machine_emergency_restart() is called, we may be on
  56  * an inconsistent state and won't be able to do a clean cleanup
  57  */
  58 static int reboot_emergency;
  59
  60 /* This is set by the PCI code if either type 1 or type 2 PCI is detected */
  61 bool port_cf9_safe = false;
  62
  63 /* reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old] | p[ci]
  64    warm   Don't set the cold reboot flag
  65    cold   Set the cold reboot flag
  66    bios   Reboot by jumping through the BIOS (only for X86_32)
  67    smp    Reboot by executing reset on BSP or other CPU (only for X86_32)
  68    triple Force a triple fault (init)
  69    kbd    Use the keyboard controller. cold reset (default)
  70    acpi   Use the RESET_REG in the FADT
  71    efi    Use efi reset_system runtime service
  72    pci    Use the so-called "PCI reset register", CF9
  73    force  Avoid anything that could hang.
  74  */
  75 static int __init reboot_setup(char *str)
  76 {
  77         for (;;) {
  78                 /* Having anything passed on the command line via
  79                  * reboot= will cause us to disable DMI checking
  80                  * below.
  81                  */
  82                 reboot_default = 0;
  83
  84                 switch (*str) {
  85                 case 'w':
  86                         reboot_mode = 0x1234;
  87                         break;
  88
  89                 case 'c':
  90                         reboot_mode = 0;
  91                         break;
  92
  93 #ifdef CONFIG_X86_32
  94 #ifdef CONFIG_SMP
  95                 case 's':
  96                         if (isdigit(*(str+1))) {
  97                                 reboot_cpu = (int) (*(str+1) - '0');
  98                                 if (isdigit(*(str+2)))
  99                                         reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0');
 100                         }
 101                                 /* we will leave sorting out the final value
 102                                    when we are ready to reboot, since we might not
 103                                    have detected BSP APIC ID or smp_num_cpu */
 104                         break;
 105 #endif /* CONFIG_SMP */
 106
 107                 case 'b':
 108 #endif
 109                 case 'a':
 110                 case 'k':
 111                 case 't':
 112                 case 'e':
 113                 case 'p':
 114                         reboot_type = *str;
 115                         break;
 116
 117                 case 'f':
 118                         reboot_force = 1;
 119                         break;
 120                 }
 121
 122                 str = strchr(str, ',');
 123                 if (str)
 124                         str++;
 125                 else
 126                         break;
 127         }
 128         return 1;
 129 }
 130
 131 __setup("reboot=", reboot_setup);
 132
 133
 134 #ifdef CONFIG_X86_32
 135 /*
 136  * Reboot options and system auto-detection code provided by
 137  * Dell Inc. so their systems "just work". :-)
 138  */
 139
 140 /*
 141  * Some machines require the "reboot=b" or "reboot=k"  commandline options,
 142  * this quirk makes that automatic.
 143  */
 144 static int __init set_bios_reboot(const struct dmi_system_id *d)
 145 {
 146         if (reboot_type != BOOT_BIOS) {
 147                 reboot_type = BOOT_BIOS;
 148                 printk(KERN_INFO "%s series board detected. Selecting BIOS-method for reboots.\n", d->ident);
 149         }
 150         return 0;
 151 }
 152
 153 static int __init set_kbd_reboot(const struct dmi_system_id *d)
 154 {
 155         if (reboot_type != BOOT_KBD) {
 156                 reboot_type = BOOT_KBD;
 157                 printk(KERN_INFO "%s series board detected. Selecting KBD-method for reboot.\n", d->ident);
 158         }
 159         return 0;
 160 }
 161
 162 static struct dmi_system_id __initdata reboot_dmi_table[] = {
 163         {       /* Handle problems with rebooting on Dell E520's */
 164                 .callback = set_bios_reboot,
 165                 .ident = "Dell E520",
 166                 .matches = {
 167                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 168                         DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
 169                 },
 170         },
 171         {       /* Handle problems with rebooting on Dell 1300's */
 172                 .callback = set_bios_reboot,
 173                 .ident = "Dell PowerEdge 1300",
 174                 .matches = {
 175                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
 176                         DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
 177                 },
 178         },
 179         {       /* Handle problems with rebooting on Dell 300's */
 180                 .callback = set_bios_reboot,
 181                 .ident = "Dell PowerEdge 300",
 182                 .matches = {
 183                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
 184                         DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
 185                 },
 186         },
 187         {       /* Handle problems with rebooting on Dell Optiplex 745's SFF*/
 188                 .callback = set_bios_reboot,
 189                 .ident = "Dell OptiPlex 745",
 190                 .matches = {
 191                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 192                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
 193                 },
 194         },
 195         {       /* Handle problems with rebooting on Dell Optiplex 745's DFF*/
 196                 .callback = set_bios_reboot,
 197                 .ident = "Dell OptiPlex 745",
 198                 .matches = {
 199                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 200                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
 201                         DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
 202                 },
 203         },
 204         {       /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
 205                 .callback = set_bios_reboot,
 206                 .ident = "Dell OptiPlex 745",
 207                 .matches = {
 208                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 209                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
 210                         DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
 211                 },
 212         },
 213         {   /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
 214                 .callback = set_bios_reboot,
 215                 .ident = "Dell OptiPlex 330",
 216                 .matches = {
 217                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 218                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"),
 219                         DMI_MATCH(DMI_BOARD_NAME, "0KP561"),
 220                 },
 221         },
 222         {   /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
 223                 .callback = set_bios_reboot,
 224                 .ident = "Dell OptiPlex 360",
 225                 .matches = {
 226                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 227                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"),
 228                         DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
 229                 },
 230         },
 231         {       /* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G*/
 232                 .callback = set_bios_reboot,
 233                 .ident = "Dell OptiPlex 760",
 234                 .matches = {
 235                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 236                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"),
 237                         DMI_MATCH(DMI_BOARD_NAME, "0G919G"),
 238                 },
 239         },
 240         {       /* Handle problems with rebooting on Dell 2400's */
 241                 .callback = set_bios_reboot,
 242                 .ident = "Dell PowerEdge 2400",
 243                 .matches = {
 244                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
 245                         DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
 246                 },
 247         },
 248         {       /* Handle problems with rebooting on Dell T5400's */
 249                 .callback = set_bios_reboot,
 250                 .ident = "Dell Precision T5400",
 251                 .matches = {
 252                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 253                         DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"),
 254                 },
 255         },
 256         {       /* Handle problems with rebooting on Dell T7400's */
 257                 .callback = set_bios_reboot,
 258                 .ident = "Dell Precision T7400",
 259                 .matches = {
 260                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 261                         DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"),
 262                 },
 263         },
 264         {       /* Handle problems with rebooting on HP laptops */
 265                 .callback = set_bios_reboot,
 266                 .ident = "HP Compaq Laptop",
 267                 .matches = {
 268                         DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 269                         DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
 270                 },
 271         },
 272         {       /* Handle problems with rebooting on Dell XPS710 */
 273                 .callback = set_bios_reboot,
 274                 .ident = "Dell XPS710",
 275                 .matches = {
 276                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 277                         DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
 278                 },
 279         },
 280         {       /* Handle problems with rebooting on Dell DXP061 */
 281                 .callback = set_bios_reboot,
 282                 .ident = "Dell DXP061",
 283                 .matches = {
 284                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 285                         DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"),
 286                 },
 287         },
 288         {       /* Handle problems with rebooting on Sony VGN-Z540N */
 289                 .callback = set_bios_reboot,
 290                 .ident = "Sony VGN-Z540N",
 291                 .matches = {
 292                         DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 293                         DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
 294                 },
 295         },
 296         {       /* Handle problems with rebooting on CompuLab SBC-FITPC2 */
 297                 .callback = set_bios_reboot,
 298                 .ident = "CompuLab SBC-FITPC2",
 299                 .matches = {
 300                         DMI_MATCH(DMI_SYS_VENDOR, "CompuLab"),
 301                         DMI_MATCH(DMI_PRODUCT_NAME, "SBC-FITPC2"),
 302                 },
 303         },
 304         {       /* Handle problems with rebooting on ASUS P4S800 */
 305                 .callback = set_bios_reboot,
 306                 .ident = "ASUS P4S800",
 307                 .matches = {
 308                         DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
 309                         DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
 310                 },
 311         },
 312         { /* Handle reboot issue on Acer Aspire one */
 313                 .callback = set_kbd_reboot,
 314                 .ident = "Acer Aspire One A110",
 315                 .matches = {
 316                         DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
 317                         DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"),
 318                 },
 319         },
 320         { }
 321 };
 322
 323 static int __init reboot_init(void)
 324 {
 325         /* Only do the DMI check if reboot_type hasn't been overridden
 326          * on the command line
 327          */
 328         if (reboot_default) {
 329                 dmi_check_system(reboot_dmi_table);
 330         }
 331         return 0;
 332 }
 333 core_initcall(reboot_init);
 334
 335 extern const unsigned char machine_real_restart_asm[];
 336 extern const u64 machine_real_restart_gdt[3];
 337
 338 void machine_real_restart(unsigned int type)
 339 {
 340         void *restart_va;
 341         unsigned long restart_pa;
 342         void (*restart_lowmem)(unsigned int);
 343         u64 *lowmem_gdt;
 344
 345         local_irq_disable();
 346
 347         /* Write zero to CMOS register number 0x0f, which the BIOS POST
 348            routine will recognize as telling it to do a proper reboot.  (Well
 349            that's what this book in front of me says -- it may only apply to
 350            the Phoenix BIOS though, it's not clear).  At the same time,
 351            disable NMIs by setting the top bit in the CMOS address register,
 352            as we're about to do peculiar things to the CPU.  I'm not sure if
 353            `outb_p' is needed instead of just `outb'.  Use it to be on the
 354            safe side.  (Yes, CMOS_WRITE does outb_p's. -  Paul G.)
 355          */
 356         spin_lock(&rtc_lock);
 357         CMOS_WRITE(0x00, 0x8f);
 358         spin_unlock(&rtc_lock);
 359
 360         /*
 361          * Switch back to the initial page table.
 362          */
 363         load_cr3(initial_page_table);
 364
 365         /* Write 0x1234 to absolute memory location 0x472.  The BIOS reads
 366            this on booting to tell it to "Bypass memory test (also warm
 367            boot)".  This seems like a fairly standard thing that gets set by
 368            REBOOT.COM programs, and the previous reset routine did this
 369            too. */
 370         *((unsigned short *)0x472) = reboot_mode;
 371
 372         /* Patch the GDT in the low memory trampoline */
 373         lowmem_gdt = TRAMPOLINE_SYM(machine_real_restart_gdt);
 374
 375         restart_va = TRAMPOLINE_SYM(machine_real_restart_asm);
 376         restart_pa = virt_to_phys(restart_va);
 377         restart_lowmem = (void (*)(unsigned int))restart_pa;
 378
 379         /* GDT[0]: GDT self-pointer */
 380         lowmem_gdt[0] =
 381                 (u64)(sizeof(machine_real_restart_gdt) - 1) +
 382                 ((u64)virt_to_phys(lowmem_gdt) << 16);
 383         /* GDT[1]: 64K real mode code segment */
 384         lowmem_gdt[1] =
 385                 GDT_ENTRY(0x009b, restart_pa, 0xffff);
 386
 387         /* Jump to the identity-mapped low memory code */
 388         restart_lowmem(type);
 389 }
 390 #ifdef CONFIG_APM_MODULE
 391 EXPORT_SYMBOL(machine_real_restart);
 392 #endif
 393
 394 #endif /* CONFIG_X86_32 */
 395
 396 /*
 397  * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
 398  */
 399 static int __init set_pci_reboot(const struct dmi_system_id *d)
 400 {
 401         if (reboot_type != BOOT_CF9) {
 402                 reboot_type = BOOT_CF9;
 403                 printk(KERN_INFO "%s series board detected. "
 404                        "Selecting PCI-method for reboots.\n", d->ident);
 405         }
 406         return 0;
 407 }
 408
 409 static struct dmi_system_id __initdata pci_reboot_dmi_table[] = {
 410         {       /* Handle problems with rebooting on Apple MacBook5 */
 411                 .callback = set_pci_reboot,
 412                 .ident = "Apple MacBook5",
 413                 .matches = {
 414                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 415                         DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"),
 416                 },
 417         },
 418         {       /* Handle problems with rebooting on Apple MacBookPro5 */
 419                 .callback = set_pci_reboot,
 420                 .ident = "Apple MacBookPro5",
 421                 .matches = {
 422                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 423                         DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"),
 424                 },
 425         },
 426         {       /* Handle problems with rebooting on Apple Macmini3,1 */
 427                 .callback = set_pci_reboot,
 428                 .ident = "Apple Macmini3,1",
 429                 .matches = {
 430                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 431                         DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"),
 432                 },
 433         },
 434         {       /* Handle problems with rebooting on the iMac9,1. */
 435                 .callback = set_pci_reboot,
 436                 .ident = "Apple iMac9,1",
 437                 .matches = {
 438                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 439                         DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"),
 440                 },
 441         },
 442         {       /* Handle problems with rebooting on the Latitude E6320. */
 443                 .callback = set_pci_reboot,
 444                 .ident = "Dell Latitude E6320",
 445                 .matches = {
 446                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 447                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6320"),
 448                 },
 449         },
 450         {       /* Handle problems with rebooting on the Latitude E5420. */
 451                 .callback = set_pci_reboot,
 452                 .ident = "Dell Latitude E5420",
 453                 .matches = {
 454                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 455                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5420"),
 456                 },
 457         },
 458         {       /* Handle problems with rebooting on the Latitude E6420. */
 459                 .callback = set_pci_reboot,
 460                 .ident = "Dell Latitude E6420",
 461                 .matches = {
 462                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 463                         DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6420"),
 464                 },
 465         },
 466         {       /* Handle problems with rebooting on the OptiPlex 990. */
 467                 .callback = set_pci_reboot,
 468                 .ident = "Dell OptiPlex 990",
 469                 .matches = {
 470                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 471                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 990"),
 472                 },
 473         },
 474         { }
 475 };
 476
 477 static int __init pci_reboot_init(void)
 478 {
 479         /* Only do the DMI check if reboot_type hasn't been overridden
 480          * on the command line
 481          */
 482         if (reboot_default) {
 483                 dmi_check_system(pci_reboot_dmi_table);
 484         }
 485         return 0;
 486 }
 487 core_initcall(pci_reboot_init);
 488
 489 static inline void kb_wait(void)
 490 {
 491         int i;
 492
 493         for (i = 0; i < 0x10000; i++) {
 494                 if ((inb(0x64) & 0x02) == 0)
 495                         break;
 496                 udelay(2);
 497         }
 498 }
 499
 500 static void vmxoff_nmi(int cpu, struct pt_regs *regs)
 501 {
 502         cpu_emergency_vmxoff();
 503 }
 504
 505 /* Use NMIs as IPIs to tell all CPUs to disable virtualization
 506  */
 507 static void emergency_vmx_disable_all(void)
 508 {
 509         /* Just make sure we won't change CPUs while doing this */
 510         local_irq_disable();
 511
 512         /* We need to disable VMX on all CPUs before rebooting, otherwise
 513          * we risk hanging up the machine, because the CPU ignore INIT
 514          * signals when VMX is enabled.
 515          *
 516          * We can't take any locks and we may be on an inconsistent
 517          * state, so we use NMIs as IPIs to tell the other CPUs to disable
 518          * VMX and halt.
 519          *
 520          * For safety, we will avoid running the nmi_shootdown_cpus()
 521          * stuff unnecessarily, but we don't have a way to check
 522          * if other CPUs have VMX enabled. So we will call it only if the
 523          * CPU we are running on has VMX enabled.
 524          *
 525          * We will miss cases where VMX is not enabled on all CPUs. This
 526          * shouldn't do much harm because KVM always enable VMX on all
 527          * CPUs anyway. But we can miss it on the small window where KVM
 528          * is still enabling VMX.
 529          */
 530         if (cpu_has_vmx() && cpu_vmx_enabled()) {
 531                 /* Disable VMX on this CPU.
 532                  */
 533                 cpu_vmxoff();
 534
 535                 /* Halt and disable VMX on the other CPUs */
 536                 nmi_shootdown_cpus(vmxoff_nmi);
 537
 538         }
 539 }
 540
 541
 542 void __attribute__((weak)) mach_reboot_fixups(void)
 543 {
 544 }
 545
 546 /*
 547  * Windows compatible x86 hardware expects the following on reboot:
 548  *
 549  * 1) If the FADT has the ACPI reboot register flag set, try it
 550  * 2) If still alive, write to the keyboard controller
 551  * 3) If still alive, write to the ACPI reboot register again
 552  * 4) If still alive, write to the keyboard controller again
 553  *
 554  * If the machine is still alive at this stage, it gives up. We default to
 555  * following the same pattern, except that if we're still alive after (4) we'll
 556  * try to force a triple fault and then cycle between hitting the keyboard
 557  * controller and doing that
 558  */
 559 static void native_machine_emergency_restart(void)
 560 {
 561         int i;
 562         int attempt = 0;
 563         int orig_reboot_type = reboot_type;
 564
 565         if (reboot_emergency)
 566                 emergency_vmx_disable_all();
 567
 568         tboot_shutdown(TB_SHUTDOWN_REBOOT);
 569
 570         /* Tell the BIOS if we want cold or warm reboot */
 571         *((unsigned short *)__va(0x472)) = reboot_mode;
 572
 573         for (;;) {
 574                 /* Could also try the reset bit in the Hammer NB */
 575                 switch (reboot_type) {
 576                 case BOOT_KBD:
 577                         mach_reboot_fixups(); /* for board specific fixups */
 578
 579                         for (i = 0; i < 10; i++) {
 580                                 kb_wait();
 581                                 udelay(50);
 582                                 outb(0xfe, 0x64); /* pulse reset low */
 583                                 udelay(50);
 584                         }
 585                         if (attempt == 0 && orig_reboot_type == BOOT_ACPI) {
 586                                 attempt = 1;
 587                                 reboot_type = BOOT_ACPI;
 588                         } else {
 589                                 reboot_type = BOOT_TRIPLE;
 590                         }
 591                         break;
 592
 593                 case BOOT_TRIPLE:
 594                         load_idt(&no_idt);
 595                         __asm__ __volatile__("int3");
 596
 597                         reboot_type = BOOT_KBD;
 598                         break;
 599
 600 #ifdef CONFIG_X86_32
 601                 case BOOT_BIOS:
 602                         machine_real_restart(MRR_BIOS);
 603
 604                         reboot_type = BOOT_KBD;
 605                         break;
 606 #endif
 607
 608                 case BOOT_ACPI:
 609                         acpi_reboot();
 610                         reboot_type = BOOT_KBD;
 611                         break;
 612
 613                 case BOOT_EFI:
 614                         if (efi_enabled)
 615                                 efi.reset_system(reboot_mode ?
 616                                                  EFI_RESET_WARM :
 617                                                  EFI_RESET_COLD,
 618                                                  EFI_SUCCESS, 0, NULL);
 619                         reboot_type = BOOT_KBD;
 620                         break;
 621
 622                 case BOOT_CF9:
 623                         port_cf9_safe = true;
 624                         /* fall through */
 625
 626                 case BOOT_CF9_COND:
 627                         if (port_cf9_safe) {
 628                                 u8 cf9 = inb(0xcf9) & ~6;
 629                                 outb(cf9|2, 0xcf9); /* Request hard reset */
 630                                 udelay(50);
 631                                 outb(cf9|6, 0xcf9); /* Actually do the reset */
 632                                 udelay(50);
 633                         }
 634                         reboot_type = BOOT_KBD;
 635                         break;
 636                 }
 637         }
 638 }
 639
 640 void native_machine_shutdown(void)
 641 {
 642         /* Stop the cpus and apics */
 643 #ifdef CONFIG_SMP
 644
 645         /* The boot cpu is always logical cpu 0 */
 646         int reboot_cpu_id = 0;
 647
 648 #ifdef CONFIG_X86_32
 649         /* See if there has been given a command line override */
 650         if ((reboot_cpu != -1) && (reboot_cpu < nr_cpu_ids) &&
 651                 cpu_online(reboot_cpu))
 652                 reboot_cpu_id = reboot_cpu;
 653 #endif
 654
 655         /* Make certain the cpu I'm about to reboot on is online */
 656         if (!cpu_online(reboot_cpu_id))
 657                 reboot_cpu_id = smp_processor_id();
 658
 659         /* Make certain I only run on the appropriate processor */
 660         set_cpus_allowed_ptr(current, cpumask_of(reboot_cpu_id));
 661
 662         /* O.K Now that I'm on the appropriate processor,
 663          * stop all of the others.
 664          */
 665         stop_other_cpus();
 666 #endif
 667
 668         lapic_shutdown();
 669
 670 #ifdef CONFIG_X86_IO_APIC
 671         disable_IO_APIC();
 672 #endif
 673
 674 #ifdef CONFIG_HPET_TIMER
 675         hpet_disable();
 676 #endif
 677
 678 #ifdef CONFIG_X86_64
 679         x86_platform.iommu_shutdown();
 680 #endif
 681 }
 682
 683 static void __machine_emergency_restart(int emergency)
 684 {
 685         reboot_emergency = emergency;
 686         machine_ops.emergency_restart();
 687 }
 688
 689 static void native_machine_restart(char *__unused)
 690 {
 691         printk("machine restart\n");
 692
 693         if (!reboot_force)
 694                 machine_shutdown();
 695         __machine_emergency_restart(0);
 696 }
 697
 698 static void native_machine_halt(void)
 699 {
 700         /* stop other cpus and apics */
 701         machine_shutdown();
 702
 703         tboot_shutdown(TB_SHUTDOWN_HALT);
 704
 705         /* stop this cpu */
 706         stop_this_cpu(NULL);
 707 }
 708
 709 static void native_machine_power_off(void)
 710 {
 711         if (pm_power_off) {
 712                 if (!reboot_force)
 713                         machine_shutdown();
 714                 pm_power_off();
 715         }
 716         /* a fallback in case there is no PM info available */
 717         tboot_shutdown(TB_SHUTDOWN_HALT);
 718 }
 719
 720 struct machine_ops machine_ops = {
 721         .power_off = native_machine_power_off,
 722         .shutdown = native_machine_shutdown,
 723         .emergency_restart = native_machine_emergency_restart,
 724         .restart = native_machine_restart,
 725         .halt = native_machine_halt,
 726 #ifdef CONFIG_KEXEC
 727         .crash_shutdown = native_machine_crash_shutdown,
 728 #endif
 729 };
 730
 731 void machine_power_off(void)
 732 {
 733         machine_ops.power_off();
 734 }
 735
 736 void machine_shutdown(void)
 737 {
 738         machine_ops.shutdown();
 739 }
 740
 741 void machine_emergency_restart(void)
 742 {
 743         __machine_emergency_restart(1);
 744 }
 745
 746 void machine_restart(char *cmd)
 747 {
 748         machine_ops.restart(cmd);
 749 }
 750
 751 void machine_halt(void)
 752 {
 753         machine_ops.halt();
 754 }
 755
 756 #ifdef CONFIG_KEXEC
 757 void machine_crash_shutdown(struct pt_regs *regs)
 758 {
 759         machine_ops.crash_shutdown(regs);
 760 }
 761 #endif
 762
 763
 764 #if defined(CONFIG_SMP)
 765
 766 /* This keeps a track of which one is crashing cpu. */
 767 static int crashing_cpu;
 768 static nmi_shootdown_cb shootdown_callback;
 769
 770 static atomic_t waiting_for_crash_ipi;
 771
 772 static int crash_nmi_callback(unsigned int val, struct pt_regs *regs)
 773 {
 774         int cpu;
 775
 776         cpu = raw_smp_processor_id();
 777
 778         /* Don't do anything if this handler is invoked on crashing cpu.
 779          * Otherwise, system will completely hang. Crashing cpu can get
 780          * an NMI if system was initially booted with nmi_watchdog parameter.
 781          */
 782         if (cpu == crashing_cpu)
 783                 return NMI_HANDLED;
 784         local_irq_disable();
 785
 786         shootdown_callback(cpu, regs);
 787
 788         atomic_dec(&waiting_for_crash_ipi);
 789         /* Assume hlt works */
 790         halt();
 791         for (;;)
 792                 cpu_relax();
 793
 794         return NMI_HANDLED;
 795 }
 796
 797 static void smp_send_nmi_allbutself(void)
 798 {
 799         apic->send_IPI_allbutself(NMI_VECTOR);
 800 }
 801
 802 /* Halt all other CPUs, calling the specified function on each of them
 803  *
 804  * This function can be used to halt all other CPUs on crash
 805  * or emergency reboot time. The function passed as parameter
 806  * will be called inside a NMI handler on all CPUs.
 807  */
 808 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
 809 {
 810         unsigned long msecs;
 811         local_irq_disable();
 812
 813         /* Make a note of crashing cpu. Will be used in NMI callback.*/
 814         crashing_cpu = safe_smp_processor_id();
 815
 816         shootdown_callback = callback;
 817
 818         atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
 819         /* Would it be better to replace the trap vector here? */
 820         if (register_nmi_handler(NMI_LOCAL, crash_nmi_callback,
 821                                  NMI_FLAG_FIRST, "crash"))
 822                 return;         /* return what? */
 823         /* Ensure the new callback function is set before sending
 824          * out the NMI
 825          */
 826         wmb();
 827
 828         smp_send_nmi_allbutself();
 829
 830         msecs = 1000; /* Wait at most a second for the other cpus to stop */
 831         while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
 832                 mdelay(1);
 833                 msecs--;
 834         }
 835
 836         /* Leave the nmi callback set */
 837 }
 838 #else /* !CONFIG_SMP */
 839 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
 840 {
 841         /* No other CPUs to shoot down */
 842 }
 843 #endif