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 detected BSP APIC 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 Dell T7400's */
 232                 .callback = set_bios_reboot,
 233                 .ident = "Dell Precision T7400",
 234                 .matches = {
 235                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 236                         DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"),
 237                 },
 238         },
 239         {       /* Handle problems with rebooting on HP laptops */
 240                 .callback = set_bios_reboot,
 241                 .ident = "HP Compaq Laptop",
 242                 .matches = {
 243                         DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 244                         DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"),
 245                 },
 246         },
 247         {       /* Handle problems with rebooting on Dell XPS710 */
 248                 .callback = set_bios_reboot,
 249                 .ident = "Dell XPS710",
 250                 .matches = {
 251                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 252                         DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"),
 253                 },
 254         },
 255         {       /* Handle problems with rebooting on Dell DXP061 */
 256                 .callback = set_bios_reboot,
 257                 .ident = "Dell DXP061",
 258                 .matches = {
 259                         DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."),
 260                         DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"),
 261                 },
 262         },
 263         {       /* Handle problems with rebooting on Sony VGN-Z540N */
 264                 .callback = set_bios_reboot,
 265                 .ident = "Sony VGN-Z540N",
 266                 .matches = {
 267                         DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"),
 268                         DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"),
 269                 },
 270         },
 271         {       /* Handle problems with rebooting on CompuLab SBC-FITPC2 */
 272                 .callback = set_bios_reboot,
 273                 .ident = "CompuLab SBC-FITPC2",
 274                 .matches = {
 275                         DMI_MATCH(DMI_SYS_VENDOR, "CompuLab"),
 276                         DMI_MATCH(DMI_PRODUCT_NAME, "SBC-FITPC2"),
 277                 },
 278         },
 279         {       /* Handle problems with rebooting on ASUS P4S800 */
 280                 .callback = set_bios_reboot,
 281                 .ident = "ASUS P4S800",
 282                 .matches = {
 283                         DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."),
 284                         DMI_MATCH(DMI_BOARD_NAME, "P4S800"),
 285                 },
 286         },
 287         { }
 288 };
 289
 290 static int __init reboot_init(void)
 291 {
 292         dmi_check_system(reboot_dmi_table);
 293         return 0;
 294 }
 295 core_initcall(reboot_init);
 296
 297 /* The following code and data reboots the machine by switching to real
 298    mode and jumping to the BIOS reset entry point, as if the CPU has
 299    really been reset.  The previous version asked the keyboard
 300    controller to pulse the CPU reset line, which is more thorough, but
 301    doesn't work with at least one type of 486 motherboard.  It is easy
 302    to stop this code working; hence the copious comments. */
 303 static const unsigned long long
 304 real_mode_gdt_entries [3] =
 305 {
 306         0x0000000000000000ULL,  /* Null descriptor */
 307         0x00009b000000ffffULL,  /* 16-bit real-mode 64k code at 0x00000000 */
 308         0x000093000100ffffULL   /* 16-bit real-mode 64k data at 0x00000100 */
 309 };
 310
 311 static const struct desc_ptr
 312 real_mode_gdt = { sizeof (real_mode_gdt_entries) - 1, (long)real_mode_gdt_entries },
 313 real_mode_idt = { 0x3ff, 0 };
 314
 315 /* This is 16-bit protected mode code to disable paging and the cache,
 316    switch to real mode and jump to the BIOS reset code.
 317
 318    The instruction that switches to real mode by writing to CR0 must be
 319    followed immediately by a far jump instruction, which set CS to a
 320    valid value for real mode, and flushes the prefetch queue to avoid
 321    running instructions that have already been decoded in protected
 322    mode.
 323
 324    Clears all the flags except ET, especially PG (paging), PE
 325    (protected-mode enable) and TS (task switch for coprocessor state
 326    save).  Flushes the TLB after paging has been disabled.  Sets CD and
 327    NW, to disable the cache on a 486, and invalidates the cache.  This
 328    is more like the state of a 486 after reset.  I don't know if
 329    something else should be done for other chips.
 330
 331    More could be done here to set up the registers as if a CPU reset had
 332    occurred; hopefully real BIOSs don't assume much. */
 333 static const unsigned char real_mode_switch [] =
 334 {
 335         0x66, 0x0f, 0x20, 0xc0,                 /*    movl  %cr0,%eax        */
 336         0x66, 0x83, 0xe0, 0x11,                 /*    andl  $0x00000011,%eax */
 337         0x66, 0x0d, 0x00, 0x00, 0x00, 0x60,     /*    orl   $0x60000000,%eax */
 338         0x66, 0x0f, 0x22, 0xc0,                 /*    movl  %eax,%cr0        */
 339         0x66, 0x0f, 0x22, 0xd8,                 /*    movl  %eax,%cr3        */
 340         0x66, 0x0f, 0x20, 0xc3,                 /*    movl  %cr0,%ebx        */
 341         0x66, 0x81, 0xe3, 0x00, 0x00, 0x00, 0x60,       /*    andl  $0x60000000,%ebx */
 342         0x74, 0x02,                             /*    jz    f                */
 343         0x0f, 0x09,                             /*    wbinvd                 */
 344         0x24, 0x10,                             /* f: andb  $0x10,al         */
 345         0x66, 0x0f, 0x22, 0xc0                  /*    movl  %eax,%cr0        */
 346 };
 347 static const unsigned char jump_to_bios [] =
 348 {
 349         0xea, 0x00, 0x00, 0xff, 0xff            /*    ljmp  $0xffff,$0x0000  */
 350 };
 351
 352 /*
 353  * Switch to real mode and then execute the code
 354  * specified by the code and length parameters.
 355  * We assume that length will aways be less that 100!
 356  */
 357 void machine_real_restart(const unsigned char *code, int length)
 358 {
 359         local_irq_disable();
 360
 361         /* Write zero to CMOS register number 0x0f, which the BIOS POST
 362            routine will recognize as telling it to do a proper reboot.  (Well
 363            that's what this book in front of me says -- it may only apply to
 364            the Phoenix BIOS though, it's not clear).  At the same time,
 365            disable NMIs by setting the top bit in the CMOS address register,
 366            as we're about to do peculiar things to the CPU.  I'm not sure if
 367            `outb_p' is needed instead of just `outb'.  Use it to be on the
 368            safe side.  (Yes, CMOS_WRITE does outb_p's. -  Paul G.)
 369          */
 370         spin_lock(&rtc_lock);
 371         CMOS_WRITE(0x00, 0x8f);
 372         spin_unlock(&rtc_lock);
 373
 374         /*
 375          * Switch back to the initial page table.
 376          */
 377         load_cr3(initial_page_table);
 378
 379         /* Write 0x1234 to absolute memory location 0x472.  The BIOS reads
 380            this on booting to tell it to "Bypass memory test (also warm
 381            boot)".  This seems like a fairly standard thing that gets set by
 382            REBOOT.COM programs, and the previous reset routine did this
 383            too. */
 384         *((unsigned short *)0x472) = reboot_mode;
 385
 386         /* For the switch to real mode, copy some code to low memory.  It has
 387            to be in the first 64k because it is running in 16-bit mode, and it
 388            has to have the same physical and virtual address, because it turns
 389            off paging.  Copy it near the end of the first page, out of the way
 390            of BIOS variables. */
 391         memcpy((void *)(0x1000 - sizeof(real_mode_switch) - 100),
 392                 real_mode_switch, sizeof (real_mode_switch));
 393         memcpy((void *)(0x1000 - 100), code, length);
 394
 395         /* Set up the IDT for real mode. */
 396         load_idt(&real_mode_idt);
 397
 398         /* Set up a GDT from which we can load segment descriptors for real
 399            mode.  The GDT is not used in real mode; it is just needed here to
 400            prepare the descriptors. */
 401         load_gdt(&real_mode_gdt);
 402
 403         /* Load the data segment registers, and thus the descriptors ready for
 404            real mode.  The base address of each segment is 0x100, 16 times the
 405            selector value being loaded here.  This is so that the segment
 406            registers don't have to be reloaded after switching to real mode:
 407            the values are consistent for real mode operation already. */
 408         __asm__ __volatile__ ("movl $0x0010,%%eax\n"
 409                                 "\tmovl %%eax,%%ds\n"
 410                                 "\tmovl %%eax,%%es\n"
 411                                 "\tmovl %%eax,%%fs\n"
 412                                 "\tmovl %%eax,%%gs\n"
 413                                 "\tmovl %%eax,%%ss" : : : "eax");
 414
 415         /* Jump to the 16-bit code that we copied earlier.  It disables paging
 416            and the cache, switches to real mode, and jumps to the BIOS reset
 417            entry point. */
 418         __asm__ __volatile__ ("ljmp $0x0008,%0"
 419                                 :
 420                                 : "i" ((void *)(0x1000 - sizeof (real_mode_switch) - 100)));
 421 }
 422 #ifdef CONFIG_APM_MODULE
 423 EXPORT_SYMBOL(machine_real_restart);
 424 #endif
 425
 426 #endif /* CONFIG_X86_32 */
 427
 428 /*
 429  * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot
 430  */
 431 static int __init set_pci_reboot(const struct dmi_system_id *d)
 432 {
 433         if (reboot_type != BOOT_CF9) {
 434                 reboot_type = BOOT_CF9;
 435                 printk(KERN_INFO "%s series board detected. "
 436                        "Selecting PCI-method for reboots.\n", d->ident);
 437         }
 438         return 0;
 439 }
 440
 441 static struct dmi_system_id __initdata pci_reboot_dmi_table[] = {
 442         {       /* Handle problems with rebooting on Apple MacBook5 */
 443                 .callback = set_pci_reboot,
 444                 .ident = "Apple MacBook5",
 445                 .matches = {
 446                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 447                         DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"),
 448                 },
 449         },
 450         {       /* Handle problems with rebooting on Apple MacBookPro5 */
 451                 .callback = set_pci_reboot,
 452                 .ident = "Apple MacBookPro5",
 453                 .matches = {
 454                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 455                         DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"),
 456                 },
 457         },
 458         {       /* Handle problems with rebooting on Apple Macmini3,1 */
 459                 .callback = set_pci_reboot,
 460                 .ident = "Apple Macmini3,1",
 461                 .matches = {
 462                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 463                         DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"),
 464                 },
 465         },
 466         {       /* Handle problems with rebooting on the iMac9,1. */
 467                 .callback = set_pci_reboot,
 468                 .ident = "Apple iMac9,1",
 469                 .matches = {
 470                         DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."),
 471                         DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"),
 472                 },
 473         },
 474         { }
 475 };
 476
 477 static int __init pci_reboot_init(void)
 478 {
 479         dmi_check_system(pci_reboot_dmi_table);
 480         return 0;
 481 }
 482 core_initcall(pci_reboot_init);
 483
 484 static inline void kb_wait(void)
 485 {
 486         int i;
 487
 488         for (i = 0; i < 0x10000; i++) {
 489                 if ((inb(0x64) & 0x02) == 0)
 490                         break;
 491                 udelay(2);
 492         }
 493 }
 494
 495 static void vmxoff_nmi(int cpu, struct die_args *args)
 496 {
 497         cpu_emergency_vmxoff();
 498 }
 499
 500 /* Use NMIs as IPIs to tell all CPUs to disable virtualization
 501  */
 502 static void emergency_vmx_disable_all(void)
 503 {
 504         /* Just make sure we won't change CPUs while doing this */
 505         local_irq_disable();
 506
 507         /* We need to disable VMX on all CPUs before rebooting, otherwise
 508          * we risk hanging up the machine, because the CPU ignore INIT
 509          * signals when VMX is enabled.
 510          *
 511          * We can't take any locks and we may be on an inconsistent
 512          * state, so we use NMIs as IPIs to tell the other CPUs to disable
 513          * VMX and halt.
 514          *
 515          * For safety, we will avoid running the nmi_shootdown_cpus()
 516          * stuff unnecessarily, but we don't have a way to check
 517          * if other CPUs have VMX enabled. So we will call it only if the
 518          * CPU we are running on has VMX enabled.
 519          *
 520          * We will miss cases where VMX is not enabled on all CPUs. This
 521          * shouldn't do much harm because KVM always enable VMX on all
 522          * CPUs anyway. But we can miss it on the small window where KVM
 523          * is still enabling VMX.
 524          */
 525         if (cpu_has_vmx() && cpu_vmx_enabled()) {
 526                 /* Disable VMX on this CPU.
 527                  */
 528                 cpu_vmxoff();
 529
 530                 /* Halt and disable VMX on the other CPUs */
 531                 nmi_shootdown_cpus(vmxoff_nmi);
 532
 533         }
 534 }
 535
 536
 537 void __attribute__((weak)) mach_reboot_fixups(void)
 538 {
 539 }
 540
 541 static void native_machine_emergency_restart(void)
 542 {
 543         int i;
 544
 545         if (reboot_emergency)
 546                 emergency_vmx_disable_all();
 547
 548         tboot_shutdown(TB_SHUTDOWN_REBOOT);
 549
 550         /* Tell the BIOS if we want cold or warm reboot */
 551         *((unsigned short *)__va(0x472)) = reboot_mode;
 552
 553         for (;;) {
 554                 /* Could also try the reset bit in the Hammer NB */
 555                 switch (reboot_type) {
 556                 case BOOT_KBD:
 557                         mach_reboot_fixups(); /* for board specific fixups */
 558
 559                         for (i = 0; i < 10; i++) {
 560                                 kb_wait();
 561                                 udelay(50);
 562                                 outb(0xfe, 0x64); /* pulse reset low */
 563                                 udelay(50);
 564                         }
 565
 566                 case BOOT_TRIPLE:
 567                         load_idt(&no_idt);
 568                         __asm__ __volatile__("int3");
 569
 570                         reboot_type = BOOT_KBD;
 571                         break;
 572
 573 #ifdef CONFIG_X86_32
 574                 case BOOT_BIOS:
 575                         machine_real_restart(jump_to_bios, sizeof(jump_to_bios));
 576
 577                         reboot_type = BOOT_KBD;
 578                         break;
 579 #endif
 580
 581                 case BOOT_ACPI:
 582                         acpi_reboot();
 583                         reboot_type = BOOT_KBD;
 584                         break;
 585
 586                 case BOOT_EFI:
 587                         if (efi_enabled)
 588                                 efi.reset_system(reboot_mode ?
 589                                                  EFI_RESET_WARM :
 590                                                  EFI_RESET_COLD,
 591                                                  EFI_SUCCESS, 0, NULL);
 592                         reboot_type = BOOT_KBD;
 593                         break;
 594
 595                 case BOOT_CF9:
 596                         port_cf9_safe = true;
 597                         /* fall through */
 598
 599                 case BOOT_CF9_COND:
 600                         if (port_cf9_safe) {
 601                                 u8 cf9 = inb(0xcf9) & ~6;
 602                                 outb(cf9|2, 0xcf9); /* Request hard reset */
 603                                 udelay(50);
 604                                 outb(cf9|6, 0xcf9); /* Actually do the reset */
 605                                 udelay(50);
 606                         }
 607                         reboot_type = BOOT_KBD;
 608                         break;
 609                 }
 610         }
 611 }
 612
 613 void native_machine_shutdown(void)
 614 {
 615         /* Stop the cpus and apics */
 616 #ifdef CONFIG_SMP
 617
 618         /* The boot cpu is always logical cpu 0 */
 619         int reboot_cpu_id = 0;
 620
 621 #ifdef CONFIG_X86_32
 622         /* See if there has been given a command line override */
 623         if ((reboot_cpu != -1) && (reboot_cpu < nr_cpu_ids) &&
 624                 cpu_online(reboot_cpu))
 625                 reboot_cpu_id = reboot_cpu;
 626 #endif
 627
 628         /* Make certain the cpu I'm about to reboot on is online */
 629         if (!cpu_online(reboot_cpu_id))
 630                 reboot_cpu_id = smp_processor_id();
 631
 632         /* Make certain I only run on the appropriate processor */
 633         set_cpus_allowed_ptr(current, cpumask_of(reboot_cpu_id));
 634
 635         /* O.K Now that I'm on the appropriate processor,
 636          * stop all of the others.
 637          */
 638         stop_other_cpus();
 639 #endif
 640
 641         lapic_shutdown();
 642
 643 #ifdef CONFIG_X86_IO_APIC
 644         disable_IO_APIC();
 645 #endif
 646
 647 #ifdef CONFIG_HPET_TIMER
 648         hpet_disable();
 649 #endif
 650
 651 #ifdef CONFIG_X86_64
 652         x86_platform.iommu_shutdown();
 653 #endif
 654 }
 655
 656 static void __machine_emergency_restart(int emergency)
 657 {
 658         reboot_emergency = emergency;
 659         machine_ops.emergency_restart();
 660 }
 661
 662 static void native_machine_restart(char *__unused)
 663 {
 664         printk("machine restart\n");
 665
 666         if (!reboot_force)
 667                 machine_shutdown();
 668         __machine_emergency_restart(0);
 669 }
 670
 671 static void native_machine_halt(void)
 672 {
 673         /* stop other cpus and apics */
 674         machine_shutdown();
 675
 676         tboot_shutdown(TB_SHUTDOWN_HALT);
 677
 678         /* stop this cpu */
 679         stop_this_cpu(NULL);
 680 }
 681
 682 static void native_machine_power_off(void)
 683 {
 684         if (pm_power_off) {
 685                 if (!reboot_force)
 686                         machine_shutdown();
 687                 pm_power_off();
 688         }
 689         /* a fallback in case there is no PM info available */
 690         tboot_shutdown(TB_SHUTDOWN_HALT);
 691 }
 692
 693 struct machine_ops machine_ops = {
 694         .power_off = native_machine_power_off,
 695         .shutdown = native_machine_shutdown,
 696         .emergency_restart = native_machine_emergency_restart,
 697         .restart = native_machine_restart,
 698         .halt = native_machine_halt,
 699 #ifdef CONFIG_KEXEC
 700         .crash_shutdown = native_machine_crash_shutdown,
 701 #endif
 702 };
 703
 704 void machine_power_off(void)
 705 {
 706         machine_ops.power_off();
 707 }
 708
 709 void machine_shutdown(void)
 710 {
 711         machine_ops.shutdown();
 712 }
 713
 714 void machine_emergency_restart(void)
 715 {
 716         __machine_emergency_restart(1);
 717 }
 718
 719 void machine_restart(char *cmd)
 720 {
 721         machine_ops.restart(cmd);
 722 }
 723
 724 void machine_halt(void)
 725 {
 726         machine_ops.halt();
 727 }
 728
 729 #ifdef CONFIG_KEXEC
 730 void machine_crash_shutdown(struct pt_regs *regs)
 731 {
 732         machine_ops.crash_shutdown(regs);
 733 }
 734 #endif
 735
 736
 737 #if defined(CONFIG_SMP)
 738
 739 /* This keeps a track of which one is crashing cpu. */
 740 static int crashing_cpu;
 741 static nmi_shootdown_cb shootdown_callback;
 742
 743 static atomic_t waiting_for_crash_ipi;
 744
 745 static int crash_nmi_callback(struct notifier_block *self,
 746                         unsigned long val, void *data)
 747 {
 748         int cpu;
 749
 750         if (val != DIE_NMI_IPI)
 751                 return NOTIFY_OK;
 752
 753         cpu = raw_smp_processor_id();
 754
 755         /* Don't do anything if this handler is invoked on crashing cpu.
 756          * Otherwise, system will completely hang. Crashing cpu can get
 757          * an NMI if system was initially booted with nmi_watchdog parameter.
 758          */
 759         if (cpu == crashing_cpu)
 760                 return NOTIFY_STOP;
 761         local_irq_disable();
 762
 763         shootdown_callback(cpu, (struct die_args *)data);
 764
 765         atomic_dec(&waiting_for_crash_ipi);
 766         /* Assume hlt works */
 767         halt();
 768         for (;;)
 769                 cpu_relax();
 770
 771         return 1;
 772 }
 773
 774 static void smp_send_nmi_allbutself(void)
 775 {
 776         apic->send_IPI_allbutself(NMI_VECTOR);
 777 }
 778
 779 static struct notifier_block crash_nmi_nb = {
 780         .notifier_call = crash_nmi_callback,
 781 };
 782
 783 /* Halt all other CPUs, calling the specified function on each of them
 784  *
 785  * This function can be used to halt all other CPUs on crash
 786  * or emergency reboot time. The function passed as parameter
 787  * will be called inside a NMI handler on all CPUs.
 788  */
 789 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
 790 {
 791         unsigned long msecs;
 792         local_irq_disable();
 793
 794         /* Make a note of crashing cpu. Will be used in NMI callback.*/
 795         crashing_cpu = safe_smp_processor_id();
 796
 797         shootdown_callback = callback;
 798
 799         atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1);
 800         /* Would it be better to replace the trap vector here? */
 801         if (register_die_notifier(&crash_nmi_nb))
 802                 return;         /* return what? */
 803         /* Ensure the new callback function is set before sending
 804          * out the NMI
 805          */
 806         wmb();
 807
 808         smp_send_nmi_allbutself();
 809
 810         msecs = 1000; /* Wait at most a second for the other cpus to stop */
 811         while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) {
 812                 mdelay(1);
 813                 msecs--;
 814         }
 815
 816         /* Leave the nmi callback set */
 817 }
 818 #else /* !CONFIG_SMP */
 819 void nmi_shootdown_cpus(nmi_shootdown_cb callback)
 820 {
 821         /* No other CPUs to shoot down */
 822 }
 823 #endif