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 <acpi/reboot.h>
  10 #include <asm/io.h>
  11 #include <asm/apic.h>
  12 #include <asm/desc.h>
  13 #include <asm/hpet.h>
  14 #include <asm/pgtable.h>
  15 #include <asm/proto.h>
  16 #include <asm/reboot_fixups.h>
  17 #include <asm/reboot.h>
  18 #include <asm/pci_x86.h>
  19 #include <asm/virtext.h>
  20 #include <asm/cpu.h>
  21
  22 #ifdef CONFIG_X86_32
  23 # include <linux/ctype.h>
  24 # include <linux/mc146818rtc.h>
  25 #else
  26 # include <asm/x86_init.h>
  27 #endif
  28
  29 /*
  30  * Power off function, if any
  31  */
  32 void (*pm_power_off)(void);
  33 EXPORT_SYMBOL(pm_power_off);
  34
  35 static const struct desc_ptr no_idt = {};
  36 static int reboot_mode;
  37 enum reboot_type reboot_type = BOOT_KBD;
  38 int reboot_force;
  39
  40 #if defined(CONFIG_X86_32) && defined(CONFIG_SMP)
  41 static int reboot_cpu = -1;
  42 #endif
  43
  44 /* This is set if we need to go through the 'emergency' path.
  45  * When machine_emergency_restart() is called, we may be on
  46  * an inconsistent state and won't be able to do a clean cleanup
  47  */
  48 static int reboot_emergency;
  49
  50 /* This is set by the PCI code if either type 1 or type 2 PCI is detected */
  51 bool port_cf9_safe = false;
  52
  53 /* reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old] | p[ci]
  54    warm   Don't set the cold reboot flag
  55    cold   Set the cold reboot flag
  56    bios   Reboot by jumping through the BIOS (only for X86_32)
  57    smp    Reboot by executing reset on BSP or other CPU (only for X86_32)
  58    triple Force a triple fault (init)
  59    kbd    Use the keyboard controller. cold reset (default)
  60    acpi   Use the RESET_REG in the FADT
  61    efi    Use efi reset_system runtime service
  62    pci    Use the so-called "PCI reset register", CF9
  63    force  Avoid anything that could hang.
  64  */
  65 static int __init reboot_setup(char *str)
  66 {
  67         for (;;) {
  68                 switch (*str) {
  69                 case 'w':
  70                         reboot_mode = 0x1234;
  71                         break;
  72
  73                 case 'c':
  74                         reboot_mode = 0;
  75                         break;
  76
  77 #ifdef CONFIG_X86_32
  78 #ifdef CONFIG_SMP
  79                 case 's':
  80                         if (isdigit(*(str+1))) {
  81                                 reboot_cpu = (int) (*(str+1) - '0');
  82                                 if (isdigit(*(str+2)))
  83                                         reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0');
  84                         }
  85                                 /* we will leave sorting out the final value
  86                                    when we are ready to reboot, since we might not
  87                                    have set up boot_cpu_id or smp_num_cpu */
  88                         break;
  89 #endif /* CONFIG_SMP */
  90
  91                 case 'b':
  92 #endif
  93                 case 'a':
  94                 case 'k':
  95                 case 't':
  96                 case 'e':
  97                 case 'p':
  98                         reboot_type = *str;
  99                         break;
 100
 101                 case 'f':
 102                         reboot_force = 1;
 103                         break;
 104                 }
 105
 106                 str = strchr(str, ',');
 107                 if (str)
 108                         str++;
 109                 else
 110                         break;
 111         }
 112         return 1;
 113 }
 114
 115 __setup("reboot=", reboot_setup);
 116
 117
 118 #ifdef CONFIG_X86_32
 119 /*
 120  * Reboot options and system auto-detection code provided by
 121  * Dell Inc. so their systems "just work". :-)
 122  */
 123
 124 /*
 125  * Some machines require the "reboot=b"  commandline option,
 126  * this quirk makes that automatic.
 127  */
 128 static int __init set_bios_reboot(const struct dmi_system_id *d)
 129 {
 130         if (reboot_type != BOOT_BIOS) {
 131                 reboot_type = BOOT_BIOS;
 132                 printk(KERN_INFO "%s series board detected. Selecting BIOS-method for reboots.\n", d->ident);
 133         }
 134         return 0;
 135 }
 136
 137 static struct dmi_system_id __initdata reboot_dmi_table[] = {
 138         {       /* Handle problems with rebooting on Dell E520's */
 139                 .callback = set_bios_reboot,
 140                 .ident = "Dell E520",
 141                 .matches = {
 142                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 143                         DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"),
 144                 },
 145         },
 146         {       /* Handle problems with rebooting on Dell 1300's */
 147                 .callback = set_bios_reboot,
 148                 .ident = "Dell PowerEdge 1300",
 149                 .matches = {
 150                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
 151                         DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"),
 152                 },
 153         },
 154         {       /* Handle problems with rebooting on Dell 300's */
 155                 .callback = set_bios_reboot,
 156                 .ident = "Dell PowerEdge 300",
 157                 .matches = {
 158                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
 159                         DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"),
 160                 },
 161         },
 162         {       /* Handle problems with rebooting on Dell Optiplex 745's SFF*/
 163                 .callback = set_bios_reboot,
 164                 .ident = "Dell OptiPlex 745",
 165                 .matches = {
 166                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 167                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
 168                 },
 169         },
 170         {       /* Handle problems with rebooting on Dell Optiplex 745's DFF*/
 171                 .callback = set_bios_reboot,
 172                 .ident = "Dell OptiPlex 745",
 173                 .matches = {
 174                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 175                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
 176                         DMI_MATCH(DMI_BOARD_NAME, "0MM599"),
 177                 },
 178         },
 179         {       /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */
 180                 .callback = set_bios_reboot,
 181                 .ident = "Dell OptiPlex 745",
 182                 .matches = {
 183                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 184                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"),
 185                         DMI_MATCH(DMI_BOARD_NAME, "0KW626"),
 186                 },
 187         },
 188         {   /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */
 189                 .callback = set_bios_reboot,
 190                 .ident = "Dell OptiPlex 330",
 191                 .matches = {
 192                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 193                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"),
 194                         DMI_MATCH(DMI_BOARD_NAME, "0KP561"),
 195                 },
 196         },
 197         {   /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */
 198                 .callback = set_bios_reboot,
 199                 .ident = "Dell OptiPlex 360",
 200                 .matches = {
 201                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 202                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"),
 203                         DMI_MATCH(DMI_BOARD_NAME, "0T656F"),
 204                 },
 205         },
 206         {       /* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G*/
 207                 .callback = set_bios_reboot,
 208                 .ident = "Dell OptiPlex 760",
 209                 .matches = {
 210                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 211                         DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"),
 212                         DMI_MATCH(DMI_BOARD_NAME, "0G919G"),
 213                 },
 214         },
 215         {       /* Handle problems with rebooting on Dell 2400's */
 216                 .callback = set_bios_reboot,
 217                 .ident = "Dell PowerEdge 2400",
 218                 .matches = {
 219                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
 220                         DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"),
 221                 },
 222         },
 223         {       /* Handle problems with rebooting on Dell T5400's */
 224                 .callback = set_bios_reboot,
 225                 .ident = "Dell Precision T5400",
 226                 .matches = {
 227                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 228                         DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"),
 229                 },
 230         },
 231         {       /* Handle problems with rebooting on HP laptops */
 232                 .callback = set_bios_reboot,
 233                 .ident = "HP Compaq Laptop",
 234                 .matches = {
 235                         DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 236                         DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
 237                 },
 238         },
 239         {       /* Handle problems with rebooting on Dell XPS710 */
 240                 .callback = set_bios_reboot,
 241                 .ident = "Dell XPS710",
 242                 .matches = {
 243                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 244                         DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
 245                 },
 246         },
 247         {       /* Handle problems with rebooting on Dell DXP061 */
 248                 .callback = set_bios_reboot,
 249                 .ident = "Dell DXP061",
 250                 .matches = {
 251                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 252                         DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"),
 253                 },
 254         },
 255         {       /* Handle problems with rebooting on Sony VGN-Z540N */
 256                 .callback = set_bios_reboot,
 257                 .ident = "Sony VGN-Z540N",
 258                 .matches = {
 259                         DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 260                         DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
 261                 },
 262         },
 263         {       /* Handle problems with rebooting on CompuLab SBC-FITPC2 */
 264                 .callback = set_bios_reboot,
 265                 .ident = "CompuLab SBC-FITPC2",
 266                 .matches = {
 267                         DMI_MATCH(DMI_SYS_VENDOR, "CompuLab"),
 268                         DMI_MATCH(DMI_PRODUCT_NAME, "SBC-FITPC2"),
 269                 },
 270         },
 271         {       /* Handle problems with rebooting on ASUS P4S800 */
 272                 .callback = set_bios_reboot,
 273                 .ident = "ASUS P4S800",
 274                 .matches = {
 275                         DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
 276                         DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
 277                 },
 278         },
 279         { }
 280 };
 281
 282 static int __init reboot_init(void)
 283 {
 284         dmi_check_system(reboot_dmi_table);
 285         return 0;
 286 }
 287 core_initcall(reboot_init);
 288
 289 /* The following code and data reboots the machine by switching to real
 290    mode and jumping to the BIOS reset entry point, as if the CPU has
 291    really been reset.  The previous version asked the keyboard
 292    controller to pulse the CPU reset line, which is more thorough, but
 293    doesn't work with at least one type of 486 motherboard.  It is easy
 294    to stop this code working; hence the copious comments. */
 295 static const unsigned long long
 296 real_mode_gdt_entries [3] =
 297 {
 298         0x0000000000000000ULL,  /* Null descriptor */
 299         0x00009b000000ffffULL,  /* 16-bit real-mode 64k code at 0x00000000 */
 300         0x000093000100ffffULL   /* 16-bit real-mode 64k data at 0x00000100 */
 301 };
 302
 303 static const struct desc_ptr
 304 real_mode_gdt = { sizeof (real_mode_gdt_entries) - 1, (long)real_mode_gdt_entries },
 305 real_mode_idt = { 0x3ff, 0 };
 306
 307 /* This is 16-bit protected mode code to disable paging and the cache,
 308    switch to real mode and jump to the BIOS reset code.
 309
 310    The instruction that switches to real mode by writing to CR0 must be
 311    followed immediately by a far jump instruction, which set CS to a
 312    valid value for real mode, and flushes the prefetch queue to avoid
 313    running instructions that have already been decoded in protected
 314    mode.
 315
 316    Clears all the flags except ET, especially PG (paging), PE
 317    (protected-mode enable) and TS (task switch for coprocessor state
 318    save).  Flushes the TLB after paging has been disabled.  Sets CD and
 319    NW, to disable the cache on a 486, and invalidates the cache.  This
 320    is more like the state of a 486 after reset.  I don't know if
 321    something else should be done for other chips.
 322
 323    More could be done here to set up the registers as if a CPU reset had
 324    occurred; hopefully real BIOSs don't assume much. */
 325 static const unsigned char real_mode_switch [] =
 326 {
 327         0x66, 0x0f, 0x20, 0xc0,                 /*    movl  %cr0,%eax        */
 328         0x66, 0x83, 0xe0, 0x11,                 /*    andl  $0x00000011,%eax */
 329         0x66, 0x0d, 0x00, 0x00, 0x00, 0x60,     /*    orl   $0x60000000,%eax */
 330         0x66, 0x0f, 0x22, 0xc0,                 /*    movl  %eax,%cr0        */
 331         0x66, 0x0f, 0x22, 0xd8,                 /*    movl  %eax,%cr3        */
 332         0x66, 0x0f, 0x20, 0xc3,                 /*    movl  %cr0,%ebx        */
 333         0x66, 0x81, 0xe3, 0x00, 0x00, 0x00, 0x60,       /*    andl  $0x60000000,%ebx */
 334         0x74, 0x02,                             /*    jz    f                */
 335         0x0f, 0x09,                             /*    wbinvd                 */
 336         0x24, 0x10,                             /* f: andb  $0x10,al         */
 337         0x66, 0x0f, 0x22, 0xc0                  /*    movl  %eax,%cr0        */
 338 };
 339 static const unsigned char jump_to_bios [] =
 340 {
 341         0xea, 0x00, 0x00, 0xff, 0xff            /*    ljmp  $0xffff,$0x0000  */
 342 };
 343
 344 /*
 345  * Switch to real mode and then execute the code
 346  * specified by the code and length parameters.
 347  * We assume that length will aways be less that 100!
 348  */
 349 void machine_real_restart(const unsigned char *code, int length)
 350 {
 351         local_irq_disable();
 352
 353         /* Write zero to CMOS register number 0x0f, which the BIOS POST
 354            routine will recognize as telling it to do a proper reboot.  (Well
 355            that's what this book in front of me says -- it may only apply to
 356            the Phoenix BIOS though, it's not clear).  At the same time,
 357            disable NMIs by setting the top bit in the CMOS address register,
 358            as we're about to do peculiar things to the CPU.  I'm not sure if
 359            `outb_p' is needed instead of just `outb'.  Use it to be on the
 360            safe side.  (Yes, CMOS_WRITE does outb_p's. -  Paul G.)
 361          */
 362         spin_lock(&rtc_lock);
 363         CMOS_WRITE(0x00, 0x8f);
 364         spin_unlock(&rtc_lock);
 365
 366         /* Remap the kernel at virtual address zero, as well as offset zero
 367            from the kernel segment.  This assumes the kernel segment starts at
 368            virtual address PAGE_OFFSET. */
 369         memcpy(swapper_pg_dir, swapper_pg_dir + KERNEL_PGD_BOUNDARY,
 370                 sizeof(swapper_pg_dir [0]) * KERNEL_PGD_PTRS);
 371
 372         /*
 373          * Use `swapper_pg_dir' as our page directory.
 374          */
 375         load_cr3(swapper_pg_dir);
 376
 377         /* Write 0x1234 to absolute memory location 0x472.  The BIOS reads
 378            this on booting to tell it to "Bypass memory test (also warm
 379            boot)".  This seems like a fairly standard thing that gets set by
 380            REBOOT.COM programs, and the previous reset routine did this
 381            too. */
 382         *((unsigned short *)0x472) = reboot_mode;
 383
 384         /* For the switch to real mode, copy some code to low memory.  It has
 385            to be in the first 64k because it is running in 16-bit mode, and it
 386            has to have the same physical and virtual address, because it turns
 387            off paging.  Copy it near the end of the first page, out of the way
 388            of BIOS variables. */
 389         memcpy((void *)(0x1000 - sizeof(real_mode_switch) - 100),
 390                 real_mode_switch, sizeof (real_mode_switch));
 391         memcpy((void *)(0x1000 - 100), code, length);
 392
 393         /* Set up the IDT for real mode. */
 394         load_idt(&real_mode_idt);
 395
 396         /* Set up a GDT from which we can load segment descriptors for real
 397            mode.  The GDT is not used in real mode; it is just needed here to
 398            prepare the descriptors. */
 399         load_gdt(&real_mode_gdt);
 400
 401         /* Load the data segment registers, and thus the descriptors ready for
 402            real mode.  The base address of each segment is 0x100, 16 times the
 403            selector value being loaded here.  This is so that the segment
 404            registers don't have to be reloaded after switching to real mode:
 405            the values are consistent for real mode operation already. */
 406         __asm__ __volatile__ ("movl $0x0010,%%eax\n"
 407                                 "\tmovl %%eax,%%ds\n"
 408                                 "\tmovl %%eax,%%es\n"
 409                                 "\tmovl %%eax,%%fs\n"
 410                                 "\tmovl %%eax,%%gs\n"
 411                                 "\tmovl %%eax,%%ss" : : : "eax");
 412
 413         /* Jump to the 16-bit code that we copied earlier.  It disables paging
 414            and the cache, switches to real mode, and jumps to the BIOS reset
 415            entry point. */
 416         __asm__ __volatile__ ("ljmp $0x0008,%0"
 417                                 :
 418                                 : "i" ((void *)(0x1000 - sizeof (real_mode_switch) - 100)));
 419 }
 420 #ifdef CONFIG_APM_MODULE
 421 EXPORT_SYMBOL(machine_real_restart);
 422 #endif
 423
 424 #endif /* CONFIG_X86_32 */
 425
 426 /*
 427  * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
 428  */
 429 static int __init set_pci_reboot(const struct dmi_system_id *d)
 430 {
 431         if (reboot_type != BOOT_CF9) {
 432                 reboot_type = BOOT_CF9;
 433                 printk(KERN_INFO "%s series board detected. "
 434                        "Selecting PCI-method for reboots.\n", d->ident);
 435         }
 436         return 0;
 437 }
 438
 439 static struct dmi_system_id __initdata pci_reboot_dmi_table[] = {
 440         {       /* Handle problems with rebooting on Apple MacBook5 */
 441                 .callback = set_pci_reboot,
 442                 .ident = "Apple MacBook5",
 443                 .matches = {
 444                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 445                         DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"),
 446                 },
 447         },
 448         {       /* Handle problems with rebooting on Apple MacBookPro5 */
 449                 .callback = set_pci_reboot,
 450                 .ident = "Apple MacBookPro5",
 451                 .matches = {
 452                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 453                         DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"),
 454                 },
 455         },
 456         {       /* Handle problems with rebooting on Apple Macmini3,1 */
 457                 .callback = set_pci_reboot,
 458                 .ident = "Apple Macmini3,1",
 459                 .matches = {
 460                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 461                         DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"),
 462                 },
 463         },
 464         { }
 465 };
 466
 467 static int __init pci_reboot_init(void)
 468 {
 469         dmi_check_system(pci_reboot_dmi_table);
 470         return 0;
 471 }
 472 core_initcall(pci_reboot_init);
 473
 474 static inline void kb_wait(void)
 475 {
 476         int i;
 477
 478         for (i = 0; i < 0x10000; i++) {
 479                 if ((inb(0x64) & 0x02) == 0)
 480                         break;
 481                 udelay(2);
 482         }
 483 }
 484
 485 static void vmxoff_nmi(int cpu, struct die_args *args)
 486 {
 487         cpu_emergency_vmxoff();
 488 }
 489
 490 /* Use NMIs as IPIs to tell all CPUs to disable virtualization
 491  */
 492 static void emergency_vmx_disable_all(void)
 493 {
 494         /* Just make sure we won't change CPUs while doing this */
 495         local_irq_disable();
 496
 497         /* We need to disable VMX on all CPUs before rebooting, otherwise
 498          * we risk hanging up the machine, because the CPU ignore INIT
 499          * signals when VMX is enabled.
 500          *
 501          * We can't take any locks and we may be on an inconsistent
 502          * state, so we use NMIs as IPIs to tell the other CPUs to disable
 503          * VMX and halt.
 504          *
 505          * For safety, we will avoid running the nmi_shootdown_cpus()
 506          * stuff unnecessarily, but we don't have a way to check
 507          * if other CPUs have VMX enabled. So we will call it only if the
 508          * CPU we are running on has VMX enabled.
 509          *
 510          * We will miss cases where VMX is not enabled on all CPUs. This
 511          * shouldn't do much harm because KVM always enable VMX on all
 512          * CPUs anyway. But we can miss it on the small window where KVM
 513          * is still enabling VMX.
 514          */
 515         if (cpu_has_vmx() && cpu_vmx_enabled()) {
 516                 /* Disable VMX on this CPU.
 517                  */
 518                 cpu_vmxoff();
 519
 520                 /* Halt and disable VMX on the other CPUs */
 521                 nmi_shootdown_cpus(vmxoff_nmi);
 522
 523         }
 524 }
 525
 526
 527 void __attribute__((weak)) mach_reboot_fixups(void)
 528 {
 529 }
 530
 531 static void native_machine_emergency_restart(void)
 532 {
 533         int i;
 534
 535         if (reboot_emergency)
 536                 emergency_vmx_disable_all();
 537
 538         tboot_shutdown(TB_SHUTDOWN_REBOOT);
 539
 540         /* Tell the BIOS if we want cold or warm reboot */
 541         *((unsigned short *)__va(0x472)) = reboot_mode;
 542
 543         for (;;) {
 544                 /* Could also try the reset bit in the Hammer NB */
 545                 switch (reboot_type) {
 546                 case BOOT_KBD:
 547                         mach_reboot_fixups(); /* for board specific fixups */
 548
 549                         for (i = 0; i < 10; i++) {
 550                                 kb_wait();
 551                                 udelay(50);
 552                                 outb(0xfe, 0x64); /* pulse reset low */
 553                                 udelay(50);
 554                         }
 555
 556                 case BOOT_TRIPLE:
 557                         load_idt(&no_idt);
 558                         __asm__ __volatile__("int3");
 559
 560                         reboot_type = BOOT_KBD;
 561                         break;
 562
 563 #ifdef CONFIG_X86_32
 564                 case BOOT_BIOS:
 565                         machine_real_restart(jump_to_bios, sizeof(jump_to_bios));
 566
 567                         reboot_type = BOOT_KBD;
 568                         break;
 569 #endif
 570
 571                 case BOOT_ACPI:
 572                         acpi_reboot();
 573                         reboot_type = BOOT_KBD;
 574                         break;
 575
 576                 case BOOT_EFI:
 577                         if (efi_enabled)
 578                                 efi.reset_system(reboot_mode ?
 579                                                  EFI_RESET_WARM :
 580                                                  EFI_RESET_COLD,
 581                                                  EFI_SUCCESS, 0, NULL);
 582                         reboot_type = BOOT_KBD;
 583                         break;
 584
 585                 case BOOT_CF9:
 586                         port_cf9_safe = true;
 587                         /* fall through */
 588
 589                 case BOOT_CF9_COND:
 590                         if (port_cf9_safe) {
 591                                 u8 cf9 = inb(0xcf9) & ~6;
 592                                 outb(cf9|2, 0xcf9); /* Request hard reset */
 593                                 udelay(50);
 594                                 outb(cf9|6, 0xcf9); /* Actually do the reset */
 595                                 udelay(50);
 596                         }
 597                         reboot_type = BOOT_KBD;
 598                         break;
 599                 }
 600         }
 601 }
 602
 603 void native_machine_shutdown(void)
 604 {
 605         /* Stop the cpus and apics */
 606 #ifdef CONFIG_SMP
 607
 608         /* The boot cpu is always logical cpu 0 */
 609         int reboot_cpu_id = 0;
 610
 611 #ifdef CONFIG_X86_32
 612         /* See if there has been given a command line override */
 613         if ((reboot_cpu != -1) && (reboot_cpu < nr_cpu_ids) &&
 614                 cpu_online(reboot_cpu))
 615                 reboot_cpu_id = reboot_cpu;
 616 #endif
 617
 618         /* Make certain the cpu I'm about to reboot on is online */
 619         if (!cpu_online(reboot_cpu_id))
 620                 reboot_cpu_id = smp_processor_id();
 621
 622         /* Make certain I only run on the appropriate processor */
 623         set_cpus_allowed_ptr(current, cpumask_of(reboot_cpu_id));
 624
 625         /* O.K Now that I'm on the appropriate processor,
 626          * stop all of the others.
 627          */
 628         smp_send_stop();
 629 #endif
 630
 631         lapic_shutdown();
 632
 633 #ifdef CONFIG_X86_IO_APIC
 634         disable_IO_APIC();
 635 #endif
 636
 637 #ifdef CONFIG_HPET_TIMER
 638         hpet_disable();
 639 #endif
 640
 641 #ifdef CONFIG_X86_64
 642         x86_platform.iommu_shutdown();
 643 #endif
 644 }
 645
 646 static void __machine_emergency_restart(int emergency)
 647 {
 648         reboot_emergency = emergency;
 649         machine_ops.emergency_restart();
 650 }
 651
 652 static void native_machine_restart(char *__unused)
 653 {
 654         printk("machine restart\n");
 655
 656         if (!reboot_force)
 657                 machine_shutdown();
 658         __machine_emergency_restart(0);
 659 }
 660
 661 static void native_machine_halt(void)
 662 {
 663         /* stop other cpus and apics */
 664         machine_shutdown();
 665
 666         tboot_shutdown(TB_SHUTDOWN_HALT);
 667
 668         /* stop this cpu */
 669         stop_this_cpu(NULL);
 670 }
 671
 672 static void native_machine_power_off(void)
 673 {
 674         if (pm_power_off) {
 675                 if (!reboot_force)
 676                         machine_shutdown();
 677                 pm_power_off();
 678         }
 679         /* a fallback in case there is no PM info available */
 680         tboot_shutdown(TB_SHUTDOWN_HALT);
 681 }
 682
 683 struct machine_ops machine_ops = {
 684         .power_off = native_machine_power_off,
 685         .shutdown = native_machine_shutdown,
 686         .emergency_restart = native_machine_emergency_restart,
 687         .restart = native_machine_restart,
 688         .halt = native_machine_halt,
 689 #ifdef CONFIG_KEXEC
 690         .crash_shutdown = native_machine_crash_shutdown,
 691 #endif
 692 };
 693
 694 void machine_power_off(void)
 695 {
 696         machine_ops.power_off();
 697 }
 698
 699 void machine_shutdown(void)
 700 {
 701         machine_ops.shutdown();
 702 }
 703
 704 void machine_emergency_restart(void)
 705 {
 706         __machine_emergency_restart(1);
 707 }
 708
 709 void machine_restart(char *cmd)
 710 {
 711         machine_ops.restart(cmd);
 712 }
 713
 714 void machine_halt(void)
 715 {
 716         machine_ops.halt();
 717 }
 718
 719 #ifdef CONFIG_KEXEC
 720 void machine_crash_shutdown(struct pt_regs *regs)
 721 {
 722         machine_ops.crash_shutdown(regs);
 723 }
 724 #endif
 725
 726
 727 #if defined(CONFIG_SMP)
 728
 729 /* This keeps a track of which one is crashing cpu. */
 730 static int crashing_cpu;
 731 static nmi_shootdown_cb shootdown_callback;
 732
 733 static atomic_t waiting_for_crash_ipi;
 734
 735 static int crash_nmi_callback(struct notifier_block *self,
 736                         unsigned long val, void *data)
 737 {
 738         int cpu;
 739
 740         if (val != DIE_NMI_IPI)
 741                 return NOTIFY_OK;
 742
 743         cpu = raw_smp_processor_id();
 744
 745         /* Don't do anything if this handler is invoked on crashing cpu.
 746          * Otherwise, system will completely hang. Crashing cpu can get
 747          * an NMI if system was initially booted with nmi_watchdog parameter.
 748          */
 749         if (cpu == crashing_cpu)
 750                 return NOTIFY_STOP;
 751         local_irq_disable();
 752
 753         shootdown_callback(cpu, (struct die_args *)data);
 754
 755         atomic_dec(&waiting_for_crash_ipi);
 756         /* Assume hlt works */
 757         halt();
 758         for (;;)
 759                 cpu_relax();
 760
 761         return 1;
 762 }
 763
 764 static void smp_send_nmi_allbutself(void)
 765 {
 766         apic->send_IPI_allbutself(NMI_VECTOR);
 767 }
 768
 769 static struct notifier_block crash_nmi_nb = {
 770         .notifier_call = crash_nmi_callback,
 771 };
 772
 773 /* Halt all other CPUs, calling the specified function on each of them
 774  *
 775  * This function can be used to halt all other CPUs on crash
 776  * or emergency reboot time. The function passed as parameter
 777  * will be called inside a NMI handler on all CPUs.
 778  */
 779 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
 780 {
 781         unsigned long msecs;
 782         local_irq_disable();
 783
 784         /* Make a note of crashing cpu. Will be used in NMI callback.*/
 785         crashing_cpu = safe_smp_processor_id();
 786
 787         shootdown_callback = callback;
 788
 789         atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
 790         /* Would it be better to replace the trap vector here? */
 791         if (register_die_notifier(&crash_nmi_nb))
 792                 return;         /* return what? */
 793         /* Ensure the new callback function is set before sending
 794          * out the NMI
 795          */
 796         wmb();
 797
 798         smp_send_nmi_allbutself();
 799
 800         msecs = 1000; /* Wait at most a second for the other cpus to stop */
 801         while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
 802                 mdelay(1);
 803                 msecs--;
 804         }
 805
 806         /* Leave the nmi callback set */
 807 }
 808 #else /* !CONFIG_SMP */
 809 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
 810 {
 811         /* No other CPUs to shoot down */
 812 }
 813 #endif