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/iommu.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         {       /* Handle problems with rebooting on the iMac9,1. */
 465                 .callback = set_pci_reboot,
 466                 .ident = "Apple iMac9,1",
 467                 .matches = {
 468                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 469                         DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"),
 470                 },
 471         },
 472         { }
 473 };
 474
 475 static int __init pci_reboot_init(void)
 476 {
 477         dmi_check_system(pci_reboot_dmi_table);
 478         return 0;
 479 }
 480 core_initcall(pci_reboot_init);
 481
 482 static inline void kb_wait(void)
 483 {
 484         int i;
 485
 486         for (i = 0; i < 0x10000; i++) {
 487                 if ((inb(0x64) & 0x02) == 0)
 488                         break;
 489                 udelay(2);
 490         }
 491 }
 492
 493 static void vmxoff_nmi(int cpu, struct die_args *args)
 494 {
 495         cpu_emergency_vmxoff();
 496 }
 497
 498 /* Use NMIs as IPIs to tell all CPUs to disable virtualization
 499  */
 500 static void emergency_vmx_disable_all(void)
 501 {
 502         /* Just make sure we won't change CPUs while doing this */
 503         local_irq_disable();
 504
 505         /* We need to disable VMX on all CPUs before rebooting, otherwise
 506          * we risk hanging up the machine, because the CPU ignore INIT
 507          * signals when VMX is enabled.
 508          *
 509          * We can't take any locks and we may be on an inconsistent
 510          * state, so we use NMIs as IPIs to tell the other CPUs to disable
 511          * VMX and halt.
 512          *
 513          * For safety, we will avoid running the nmi_shootdown_cpus()
 514          * stuff unnecessarily, but we don't have a way to check
 515          * if other CPUs have VMX enabled. So we will call it only if the
 516          * CPU we are running on has VMX enabled.
 517          *
 518          * We will miss cases where VMX is not enabled on all CPUs. This
 519          * shouldn't do much harm because KVM always enable VMX on all
 520          * CPUs anyway. But we can miss it on the small window where KVM
 521          * is still enabling VMX.
 522          */
 523         if (cpu_has_vmx() && cpu_vmx_enabled()) {
 524                 /* Disable VMX on this CPU.
 525                  */
 526                 cpu_vmxoff();
 527
 528                 /* Halt and disable VMX on the other CPUs */
 529                 nmi_shootdown_cpus(vmxoff_nmi);
 530
 531         }
 532 }
 533
 534
 535 void __attribute__((weak)) mach_reboot_fixups(void)
 536 {
 537 }
 538
 539 static void native_machine_emergency_restart(void)
 540 {
 541         int i;
 542
 543         if (reboot_emergency)
 544                 emergency_vmx_disable_all();
 545
 546         tboot_shutdown(TB_SHUTDOWN_REBOOT);
 547
 548         /* Tell the BIOS if we want cold or warm reboot */
 549         *((unsigned short *)__va(0x472)) = reboot_mode;
 550
 551         for (;;) {
 552                 /* Could also try the reset bit in the Hammer NB */
 553                 switch (reboot_type) {
 554                 case BOOT_KBD:
 555                         mach_reboot_fixups(); /* for board specific fixups */
 556
 557                         for (i = 0; i < 10; i++) {
 558                                 kb_wait();
 559                                 udelay(50);
 560                                 outb(0xfe, 0x64); /* pulse reset low */
 561                                 udelay(50);
 562                         }
 563
 564                 case BOOT_TRIPLE:
 565                         load_idt(&no_idt);
 566                         __asm__ __volatile__("int3");
 567
 568                         reboot_type = BOOT_KBD;
 569                         break;
 570
 571 #ifdef CONFIG_X86_32
 572                 case BOOT_BIOS:
 573                         machine_real_restart(jump_to_bios, sizeof(jump_to_bios));
 574
 575                         reboot_type = BOOT_KBD;
 576                         break;
 577 #endif
 578
 579                 case BOOT_ACPI:
 580                         acpi_reboot();
 581                         reboot_type = BOOT_KBD;
 582                         break;
 583
 584                 case BOOT_EFI:
 585                         if (efi_enabled)
 586                                 efi.reset_system(reboot_mode ?
 587                                                  EFI_RESET_WARM :
 588                                                  EFI_RESET_COLD,
 589                                                  EFI_SUCCESS, 0, NULL);
 590                         reboot_type = BOOT_KBD;
 591                         break;
 592
 593                 case BOOT_CF9:
 594                         port_cf9_safe = true;
 595                         /* fall through */
 596
 597                 case BOOT_CF9_COND:
 598                         if (port_cf9_safe) {
 599                                 u8 cf9 = inb(0xcf9) & ~6;
 600                                 outb(cf9|2, 0xcf9); /* Request hard reset */
 601                                 udelay(50);
 602                                 outb(cf9|6, 0xcf9); /* Actually do the reset */
 603                                 udelay(50);
 604                         }
 605                         reboot_type = BOOT_KBD;
 606                         break;
 607                 }
 608         }
 609 }
 610
 611 void native_machine_shutdown(void)
 612 {
 613         /* Stop the cpus and apics */
 614 #ifdef CONFIG_SMP
 615
 616         /* The boot cpu is always logical cpu 0 */
 617         int reboot_cpu_id = 0;
 618
 619 #ifdef CONFIG_X86_32
 620         /* See if there has been given a command line override */
 621         if ((reboot_cpu != -1) && (reboot_cpu < nr_cpu_ids) &&
 622                 cpu_online(reboot_cpu))
 623                 reboot_cpu_id = reboot_cpu;
 624 #endif
 625
 626         /* Make certain the cpu I'm about to reboot on is online */
 627         if (!cpu_online(reboot_cpu_id))
 628                 reboot_cpu_id = smp_processor_id();
 629
 630         /* Make certain I only run on the appropriate processor */
 631         set_cpus_allowed_ptr(current, cpumask_of(reboot_cpu_id));
 632
 633         /* O.K Now that I'm on the appropriate processor,
 634          * stop all of the others.
 635          */
 636         stop_other_cpus();
 637 #endif
 638
 639         lapic_shutdown();
 640
 641 #ifdef CONFIG_X86_IO_APIC
 642         disable_IO_APIC();
 643 #endif
 644
 645 #ifdef CONFIG_HPET_TIMER
 646         hpet_disable();
 647 #endif
 648
 649 #ifdef CONFIG_X86_64
 650         pci_iommu_shutdown();
 651 #endif
 652 }
 653
 654 static void __machine_emergency_restart(int emergency)
 655 {
 656         reboot_emergency = emergency;
 657         machine_ops.emergency_restart();
 658 }
 659
 660 static void native_machine_restart(char *__unused)
 661 {
 662         printk("machine restart\n");
 663
 664         if (!reboot_force)
 665                 machine_shutdown();
 666         __machine_emergency_restart(0);
 667 }
 668
 669 static void native_machine_halt(void)
 670 {
 671         /* stop other cpus and apics */
 672         machine_shutdown();
 673
 674         tboot_shutdown(TB_SHUTDOWN_HALT);
 675
 676         /* stop this cpu */
 677         stop_this_cpu(NULL);
 678 }
 679
 680 static void native_machine_power_off(void)
 681 {
 682         if (pm_power_off) {
 683                 if (!reboot_force)
 684                         machine_shutdown();
 685                 pm_power_off();
 686         }
 687         /* a fallback in case there is no PM info available */
 688         tboot_shutdown(TB_SHUTDOWN_HALT);
 689 }
 690
 691 struct machine_ops machine_ops = {
 692         .power_off = native_machine_power_off,
 693         .shutdown = native_machine_shutdown,
 694         .emergency_restart = native_machine_emergency_restart,
 695         .restart = native_machine_restart,
 696         .halt = native_machine_halt,
 697 #ifdef CONFIG_KEXEC
 698         .crash_shutdown = native_machine_crash_shutdown,
 699 #endif
 700 };
 701
 702 void machine_power_off(void)
 703 {
 704         machine_ops.power_off();
 705 }
 706
 707 void machine_shutdown(void)
 708 {
 709         machine_ops.shutdown();
 710 }
 711
 712 void machine_emergency_restart(void)
 713 {
 714         __machine_emergency_restart(1);
 715 }
 716
 717 void machine_restart(char *cmd)
 718 {
 719         machine_ops.restart(cmd);
 720 }
 721
 722 void machine_halt(void)
 723 {
 724         machine_ops.halt();
 725 }
 726
 727 #ifdef CONFIG_KEXEC
 728 void machine_crash_shutdown(struct pt_regs *regs)
 729 {
 730         machine_ops.crash_shutdown(regs);
 731 }
 732 #endif
 733
 734
 735 #if defined(CONFIG_SMP)
 736
 737 /* This keeps a track of which one is crashing cpu. */
 738 static int crashing_cpu;
 739 static nmi_shootdown_cb shootdown_callback;
 740
 741 static atomic_t waiting_for_crash_ipi;
 742
 743 static int crash_nmi_callback(struct notifier_block *self,
 744                         unsigned long val, void *data)
 745 {
 746         int cpu;
 747
 748         if (val != DIE_NMI_IPI)
 749                 return NOTIFY_OK;
 750
 751         cpu = raw_smp_processor_id();
 752
 753         /* Don't do anything if this handler is invoked on crashing cpu.
 754          * Otherwise, system will completely hang. Crashing cpu can get
 755          * an NMI if system was initially booted with nmi_watchdog parameter.
 756          */
 757         if (cpu == crashing_cpu)
 758                 return NOTIFY_STOP;
 759         local_irq_disable();
 760
 761         shootdown_callback(cpu, (struct die_args *)data);
 762
 763         atomic_dec(&waiting_for_crash_ipi);
 764         /* Assume hlt works */
 765         halt();
 766         for (;;)
 767                 cpu_relax();
 768
 769         return 1;
 770 }
 771
 772 static void smp_send_nmi_allbutself(void)
 773 {
 774         apic->send_IPI_allbutself(NMI_VECTOR);
 775 }
 776
 777 static struct notifier_block crash_nmi_nb = {
 778         .notifier_call = crash_nmi_callback,
 779 };
 780
 781 /* Halt all other CPUs, calling the specified function on each of them
 782  *
 783  * This function can be used to halt all other CPUs on crash
 784  * or emergency reboot time. The function passed as parameter
 785  * will be called inside a NMI handler on all CPUs.
 786  */
 787 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
 788 {
 789         unsigned long msecs;
 790         local_irq_disable();
 791
 792         /* Make a note of crashing cpu. Will be used in NMI callback.*/
 793         crashing_cpu = safe_smp_processor_id();
 794
 795         shootdown_callback = callback;
 796
 797         atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
 798         /* Would it be better to replace the trap vector here? */
 799         if (register_die_notifier(&crash_nmi_nb))
 800                 return;         /* return what? */
 801         /* Ensure the new callback function is set before sending
 802          * out the NMI
 803          */
 804         wmb();
 805
 806         smp_send_nmi_allbutself();
 807
 808         msecs = 1000; /* Wait at most a second for the other cpus to stop */
 809         while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
 810                 mdelay(1);
 811                 msecs--;
 812         }
 813
 814         /* Leave the nmi callback set */
 815 }
 816 #else /* !CONFIG_SMP */
 817 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
 818 {
 819         /* No other CPUs to shoot down */
 820 }
 821 #endif