1 // SPDX-License-Identifier: GPL-2.0 2 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 3 4 #include <linux/export.h> 5 #include <linux/reboot.h> 6 #include <linux/init.h> 7 #include <linux/pm.h> 8 #include <linux/efi.h> 9 #include <linux/dmi.h> 10 #include <linux/sched.h> 11 #include <linux/tboot.h> 12 #include <linux/delay.h> 13 #include <linux/objtool.h> 14 #include <linux/pgtable.h> 15 #include <acpi/reboot.h> 16 #include <asm/io.h> 17 #include <asm/apic.h> 18 #include <asm/io_apic.h> 19 #include <asm/desc.h> 20 #include <asm/hpet.h> 21 #include <asm/proto.h> 22 #include <asm/reboot_fixups.h> 23 #include <asm/reboot.h> 24 #include <asm/pci_x86.h> 25 #include <asm/virtext.h> 26 #include <asm/cpu.h> 27 #include <asm/nmi.h> 28 #include <asm/smp.h> 29 30 #include <linux/ctype.h> 31 #include <linux/mc146818rtc.h> 32 #include <asm/realmode.h> 33 #include <asm/x86_init.h> 34 #include <asm/efi.h> 35 36 /* 37 * Power off function, if any 38 */ 39 void (*pm_power_off)(void); 40 EXPORT_SYMBOL(pm_power_off); 41 42 /* 43 * This is set if we need to go through the 'emergency' path. 44 * When machine_emergency_restart() is called, we may be on 45 * an inconsistent state and won't be able to do a clean cleanup 46 */ 47 static int reboot_emergency; 48 49 /* This is set by the PCI code if either type 1 or type 2 PCI is detected */ 50 bool port_cf9_safe = false; 51 52 /* 53 * Reboot options and system auto-detection code provided by 54 * Dell Inc. so their systems "just work". :-) 55 */ 56 57 /* 58 * Some machines require the "reboot=a" commandline options 59 */ 60 static int __init set_acpi_reboot(const struct dmi_system_id *d) 61 { 62 if (reboot_type != BOOT_ACPI) { 63 reboot_type = BOOT_ACPI; 64 pr_info("%s series board detected. Selecting %s-method for reboots.\n", 65 d->ident, "ACPI"); 66 } 67 return 0; 68 } 69 70 /* 71 * Some machines require the "reboot=b" or "reboot=k" commandline options, 72 * this quirk makes that automatic. 73 */ 74 static int __init set_bios_reboot(const struct dmi_system_id *d) 75 { 76 if (reboot_type != BOOT_BIOS) { 77 reboot_type = BOOT_BIOS; 78 pr_info("%s series board detected. Selecting %s-method for reboots.\n", 79 d->ident, "BIOS"); 80 } 81 return 0; 82 } 83 84 /* 85 * Some machines don't handle the default ACPI reboot method and 86 * require the EFI reboot method: 87 */ 88 static int __init set_efi_reboot(const struct dmi_system_id *d) 89 { 90 if (reboot_type != BOOT_EFI && !efi_runtime_disabled()) { 91 reboot_type = BOOT_EFI; 92 pr_info("%s series board detected. Selecting EFI-method for reboot.\n", d->ident); 93 } 94 return 0; 95 } 96 97 void __noreturn machine_real_restart(unsigned int type) 98 { 99 local_irq_disable(); 100 101 /* 102 * Write zero to CMOS register number 0x0f, which the BIOS POST 103 * routine will recognize as telling it to do a proper reboot. (Well 104 * that's what this book in front of me says -- it may only apply to 105 * the Phoenix BIOS though, it's not clear). At the same time, 106 * disable NMIs by setting the top bit in the CMOS address register, 107 * as we're about to do peculiar things to the CPU. I'm not sure if 108 * `outb_p' is needed instead of just `outb'. Use it to be on the 109 * safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.) 110 */ 111 spin_lock(&rtc_lock); 112 CMOS_WRITE(0x00, 0x8f); 113 spin_unlock(&rtc_lock); 114 115 /* 116 * Switch to the trampoline page table. 117 */ 118 load_trampoline_pgtable(); 119 120 /* Jump to the identity-mapped low memory code */ 121 #ifdef CONFIG_X86_32 122 asm volatile("jmpl *%0" : : 123 "rm" (real_mode_header->machine_real_restart_asm), 124 "a" (type)); 125 #else 126 asm volatile("ljmpl *%0" : : 127 "m" (real_mode_header->machine_real_restart_asm), 128 "D" (type)); 129 #endif 130 unreachable(); 131 } 132 #ifdef CONFIG_APM_MODULE 133 EXPORT_SYMBOL(machine_real_restart); 134 #endif 135 STACK_FRAME_NON_STANDARD(machine_real_restart); 136 137 /* 138 * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot 139 */ 140 static int __init set_pci_reboot(const struct dmi_system_id *d) 141 { 142 if (reboot_type != BOOT_CF9_FORCE) { 143 reboot_type = BOOT_CF9_FORCE; 144 pr_info("%s series board detected. Selecting %s-method for reboots.\n", 145 d->ident, "PCI"); 146 } 147 return 0; 148 } 149 150 static int __init set_kbd_reboot(const struct dmi_system_id *d) 151 { 152 if (reboot_type != BOOT_KBD) { 153 reboot_type = BOOT_KBD; 154 pr_info("%s series board detected. Selecting %s-method for reboot.\n", 155 d->ident, "KBD"); 156 } 157 return 0; 158 } 159 160 /* 161 * This is a single dmi_table handling all reboot quirks. 162 */ 163 static const struct dmi_system_id reboot_dmi_table[] __initconst = { 164 165 /* Acer */ 166 { /* Handle reboot issue on Acer Aspire one */ 167 .callback = set_kbd_reboot, 168 .ident = "Acer Aspire One A110", 169 .matches = { 170 DMI_MATCH(DMI_SYS_VENDOR, "Acer"), 171 DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"), 172 }, 173 }, 174 { /* Handle reboot issue on Acer TravelMate X514-51T */ 175 .callback = set_efi_reboot, 176 .ident = "Acer TravelMate X514-51T", 177 .matches = { 178 DMI_MATCH(DMI_SYS_VENDOR, "Acer"), 179 DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate X514-51T"), 180 }, 181 }, 182 183 /* Apple */ 184 { /* Handle problems with rebooting on Apple MacBook5 */ 185 .callback = set_pci_reboot, 186 .ident = "Apple MacBook5", 187 .matches = { 188 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), 189 DMI_MATCH(DMI_PRODUCT_NAME, "MacBook5"), 190 }, 191 }, 192 { /* Handle problems with rebooting on Apple MacBook6,1 */ 193 .callback = set_pci_reboot, 194 .ident = "Apple MacBook6,1", 195 .matches = { 196 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), 197 DMI_MATCH(DMI_PRODUCT_NAME, "MacBook6,1"), 198 }, 199 }, 200 { /* Handle problems with rebooting on Apple MacBookPro5 */ 201 .callback = set_pci_reboot, 202 .ident = "Apple MacBookPro5", 203 .matches = { 204 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), 205 DMI_MATCH(DMI_PRODUCT_NAME, "MacBookPro5"), 206 }, 207 }, 208 { /* Handle problems with rebooting on Apple Macmini3,1 */ 209 .callback = set_pci_reboot, 210 .ident = "Apple Macmini3,1", 211 .matches = { 212 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), 213 DMI_MATCH(DMI_PRODUCT_NAME, "Macmini3,1"), 214 }, 215 }, 216 { /* Handle problems with rebooting on the iMac9,1. */ 217 .callback = set_pci_reboot, 218 .ident = "Apple iMac9,1", 219 .matches = { 220 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), 221 DMI_MATCH(DMI_PRODUCT_NAME, "iMac9,1"), 222 }, 223 }, 224 { /* Handle problems with rebooting on the iMac10,1. */ 225 .callback = set_pci_reboot, 226 .ident = "Apple iMac10,1", 227 .matches = { 228 DMI_MATCH(DMI_SYS_VENDOR, "Apple Inc."), 229 DMI_MATCH(DMI_PRODUCT_NAME, "iMac10,1"), 230 }, 231 }, 232 233 /* ASRock */ 234 { /* Handle problems with rebooting on ASRock Q1900DC-ITX */ 235 .callback = set_pci_reboot, 236 .ident = "ASRock Q1900DC-ITX", 237 .matches = { 238 DMI_MATCH(DMI_BOARD_VENDOR, "ASRock"), 239 DMI_MATCH(DMI_BOARD_NAME, "Q1900DC-ITX"), 240 }, 241 }, 242 243 /* ASUS */ 244 { /* Handle problems with rebooting on ASUS P4S800 */ 245 .callback = set_bios_reboot, 246 .ident = "ASUS P4S800", 247 .matches = { 248 DMI_MATCH(DMI_BOARD_VENDOR, "ASUSTeK Computer INC."), 249 DMI_MATCH(DMI_BOARD_NAME, "P4S800"), 250 }, 251 }, 252 { /* Handle problems with rebooting on ASUS EeeBook X205TA */ 253 .callback = set_acpi_reboot, 254 .ident = "ASUS EeeBook X205TA", 255 .matches = { 256 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 257 DMI_MATCH(DMI_PRODUCT_NAME, "X205TA"), 258 }, 259 }, 260 { /* Handle problems with rebooting on ASUS EeeBook X205TAW */ 261 .callback = set_acpi_reboot, 262 .ident = "ASUS EeeBook X205TAW", 263 .matches = { 264 DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."), 265 DMI_MATCH(DMI_PRODUCT_NAME, "X205TAW"), 266 }, 267 }, 268 269 /* Certec */ 270 { /* Handle problems with rebooting on Certec BPC600 */ 271 .callback = set_pci_reboot, 272 .ident = "Certec BPC600", 273 .matches = { 274 DMI_MATCH(DMI_SYS_VENDOR, "Certec"), 275 DMI_MATCH(DMI_PRODUCT_NAME, "BPC600"), 276 }, 277 }, 278 279 /* Dell */ 280 { /* Handle problems with rebooting on Dell DXP061 */ 281 .callback = set_bios_reboot, 282 .ident = "Dell DXP061", 283 .matches = { 284 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 285 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DXP061"), 286 }, 287 }, 288 { /* Handle problems with rebooting on Dell E520's */ 289 .callback = set_bios_reboot, 290 .ident = "Dell E520", 291 .matches = { 292 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 293 DMI_MATCH(DMI_PRODUCT_NAME, "Dell DM061"), 294 }, 295 }, 296 { /* Handle problems with rebooting on the Latitude E5410. */ 297 .callback = set_pci_reboot, 298 .ident = "Dell Latitude E5410", 299 .matches = { 300 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 301 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5410"), 302 }, 303 }, 304 { /* Handle problems with rebooting on the Latitude E5420. */ 305 .callback = set_pci_reboot, 306 .ident = "Dell Latitude E5420", 307 .matches = { 308 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 309 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E5420"), 310 }, 311 }, 312 { /* Handle problems with rebooting on the Latitude E6320. */ 313 .callback = set_pci_reboot, 314 .ident = "Dell Latitude E6320", 315 .matches = { 316 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 317 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6320"), 318 }, 319 }, 320 { /* Handle problems with rebooting on the Latitude E6420. */ 321 .callback = set_pci_reboot, 322 .ident = "Dell Latitude E6420", 323 .matches = { 324 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 325 DMI_MATCH(DMI_PRODUCT_NAME, "Latitude E6420"), 326 }, 327 }, 328 { /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */ 329 .callback = set_bios_reboot, 330 .ident = "Dell OptiPlex 330", 331 .matches = { 332 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 333 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 330"), 334 DMI_MATCH(DMI_BOARD_NAME, "0KP561"), 335 }, 336 }, 337 { /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */ 338 .callback = set_bios_reboot, 339 .ident = "Dell OptiPlex 360", 340 .matches = { 341 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 342 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 360"), 343 DMI_MATCH(DMI_BOARD_NAME, "0T656F"), 344 }, 345 }, 346 { /* Handle problems with rebooting on Dell Optiplex 745's SFF */ 347 .callback = set_bios_reboot, 348 .ident = "Dell OptiPlex 745", 349 .matches = { 350 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 351 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"), 352 }, 353 }, 354 { /* Handle problems with rebooting on Dell Optiplex 745's DFF */ 355 .callback = set_bios_reboot, 356 .ident = "Dell OptiPlex 745", 357 .matches = { 358 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 359 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"), 360 DMI_MATCH(DMI_BOARD_NAME, "0MM599"), 361 }, 362 }, 363 { /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */ 364 .callback = set_bios_reboot, 365 .ident = "Dell OptiPlex 745", 366 .matches = { 367 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 368 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"), 369 DMI_MATCH(DMI_BOARD_NAME, "0KW626"), 370 }, 371 }, 372 { /* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G */ 373 .callback = set_bios_reboot, 374 .ident = "Dell OptiPlex 760", 375 .matches = { 376 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 377 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 760"), 378 DMI_MATCH(DMI_BOARD_NAME, "0G919G"), 379 }, 380 }, 381 { /* Handle problems with rebooting on the OptiPlex 990. */ 382 .callback = set_pci_reboot, 383 .ident = "Dell OptiPlex 990 BIOS A0x", 384 .matches = { 385 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 386 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 990"), 387 DMI_MATCH(DMI_BIOS_VERSION, "A0"), 388 }, 389 }, 390 { /* Handle problems with rebooting on Dell 300's */ 391 .callback = set_bios_reboot, 392 .ident = "Dell PowerEdge 300", 393 .matches = { 394 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"), 395 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"), 396 }, 397 }, 398 { /* Handle problems with rebooting on Dell 1300's */ 399 .callback = set_bios_reboot, 400 .ident = "Dell PowerEdge 1300", 401 .matches = { 402 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"), 403 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 1300/"), 404 }, 405 }, 406 { /* Handle problems with rebooting on Dell 2400's */ 407 .callback = set_bios_reboot, 408 .ident = "Dell PowerEdge 2400", 409 .matches = { 410 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"), 411 DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 2400"), 412 }, 413 }, 414 { /* Handle problems with rebooting on the Dell PowerEdge C6100. */ 415 .callback = set_pci_reboot, 416 .ident = "Dell PowerEdge C6100", 417 .matches = { 418 DMI_MATCH(DMI_SYS_VENDOR, "Dell"), 419 DMI_MATCH(DMI_PRODUCT_NAME, "C6100"), 420 }, 421 }, 422 { /* Handle problems with rebooting on the Precision M6600. */ 423 .callback = set_pci_reboot, 424 .ident = "Dell Precision M6600", 425 .matches = { 426 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 427 DMI_MATCH(DMI_PRODUCT_NAME, "Precision M6600"), 428 }, 429 }, 430 { /* Handle problems with rebooting on Dell T5400's */ 431 .callback = set_bios_reboot, 432 .ident = "Dell Precision T5400", 433 .matches = { 434 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 435 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T5400"), 436 }, 437 }, 438 { /* Handle problems with rebooting on Dell T7400's */ 439 .callback = set_bios_reboot, 440 .ident = "Dell Precision T7400", 441 .matches = { 442 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 443 DMI_MATCH(DMI_PRODUCT_NAME, "Precision WorkStation T7400"), 444 }, 445 }, 446 { /* Handle problems with rebooting on Dell XPS710 */ 447 .callback = set_bios_reboot, 448 .ident = "Dell XPS710", 449 .matches = { 450 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 451 DMI_MATCH(DMI_PRODUCT_NAME, "Dell XPS710"), 452 }, 453 }, 454 { /* Handle problems with rebooting on Dell Optiplex 7450 AIO */ 455 .callback = set_acpi_reboot, 456 .ident = "Dell OptiPlex 7450 AIO", 457 .matches = { 458 DMI_MATCH(DMI_SYS_VENDOR, "Dell Inc."), 459 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 7450 AIO"), 460 }, 461 }, 462 463 /* Hewlett-Packard */ 464 { /* Handle problems with rebooting on HP laptops */ 465 .callback = set_bios_reboot, 466 .ident = "HP Compaq Laptop", 467 .matches = { 468 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"), 469 DMI_MATCH(DMI_PRODUCT_NAME, "HP Compaq"), 470 }, 471 }, 472 473 { /* PCIe Wifi card isn't detected after reboot otherwise */ 474 .callback = set_pci_reboot, 475 .ident = "Zotac ZBOX CI327 nano", 476 .matches = { 477 DMI_MATCH(DMI_SYS_VENDOR, "NA"), 478 DMI_MATCH(DMI_PRODUCT_NAME, "ZBOX-CI327NANO-GS-01"), 479 }, 480 }, 481 482 /* Sony */ 483 { /* Handle problems with rebooting on Sony VGN-Z540N */ 484 .callback = set_bios_reboot, 485 .ident = "Sony VGN-Z540N", 486 .matches = { 487 DMI_MATCH(DMI_SYS_VENDOR, "Sony Corporation"), 488 DMI_MATCH(DMI_PRODUCT_NAME, "VGN-Z540N"), 489 }, 490 }, 491 492 { } 493 }; 494 495 static int __init reboot_init(void) 496 { 497 int rv; 498 499 /* 500 * Only do the DMI check if reboot_type hasn't been overridden 501 * on the command line 502 */ 503 if (!reboot_default) 504 return 0; 505 506 /* 507 * The DMI quirks table takes precedence. If no quirks entry 508 * matches and the ACPI Hardware Reduced bit is set and EFI 509 * runtime services are enabled, force EFI reboot. 510 */ 511 rv = dmi_check_system(reboot_dmi_table); 512 513 if (!rv && efi_reboot_required() && !efi_runtime_disabled()) 514 reboot_type = BOOT_EFI; 515 516 return 0; 517 } 518 core_initcall(reboot_init); 519 520 static inline void kb_wait(void) 521 { 522 int i; 523 524 for (i = 0; i < 0x10000; i++) { 525 if ((inb(0x64) & 0x02) == 0) 526 break; 527 udelay(2); 528 } 529 } 530 531 static void vmxoff_nmi(int cpu, struct pt_regs *regs) 532 { 533 cpu_emergency_vmxoff(); 534 } 535 536 /* Use NMIs as IPIs to tell all CPUs to disable virtualization */ 537 static void emergency_vmx_disable_all(void) 538 { 539 /* Just make sure we won't change CPUs while doing this */ 540 local_irq_disable(); 541 542 /* 543 * Disable VMX on all CPUs before rebooting, otherwise we risk hanging 544 * the machine, because the CPU blocks INIT when it's in VMX root. 545 * 546 * We can't take any locks and we may be on an inconsistent state, so 547 * use NMIs as IPIs to tell the other CPUs to exit VMX root and halt. 548 * 549 * Do the NMI shootdown even if VMX if off on _this_ CPU, as that 550 * doesn't prevent a different CPU from being in VMX root operation. 551 */ 552 if (cpu_has_vmx()) { 553 /* Safely force _this_ CPU out of VMX root operation. */ 554 __cpu_emergency_vmxoff(); 555 556 /* Halt and exit VMX root operation on the other CPUs. */ 557 nmi_shootdown_cpus(vmxoff_nmi); 558 } 559 } 560 561 562 void __attribute__((weak)) mach_reboot_fixups(void) 563 { 564 } 565 566 /* 567 * To the best of our knowledge Windows compatible x86 hardware expects 568 * the following on reboot: 569 * 570 * 1) If the FADT has the ACPI reboot register flag set, try it 571 * 2) If still alive, write to the keyboard controller 572 * 3) If still alive, write to the ACPI reboot register again 573 * 4) If still alive, write to the keyboard controller again 574 * 5) If still alive, call the EFI runtime service to reboot 575 * 6) If no EFI runtime service, call the BIOS to do a reboot 576 * 577 * We default to following the same pattern. We also have 578 * two other reboot methods: 'triple fault' and 'PCI', which 579 * can be triggered via the reboot= kernel boot option or 580 * via quirks. 581 * 582 * This means that this function can never return, it can misbehave 583 * by not rebooting properly and hanging. 584 */ 585 static void native_machine_emergency_restart(void) 586 { 587 int i; 588 int attempt = 0; 589 int orig_reboot_type = reboot_type; 590 unsigned short mode; 591 592 if (reboot_emergency) 593 emergency_vmx_disable_all(); 594 595 tboot_shutdown(TB_SHUTDOWN_REBOOT); 596 597 /* Tell the BIOS if we want cold or warm reboot */ 598 mode = reboot_mode == REBOOT_WARM ? 0x1234 : 0; 599 *((unsigned short *)__va(0x472)) = mode; 600 601 /* 602 * If an EFI capsule has been registered with the firmware then 603 * override the reboot= parameter. 604 */ 605 if (efi_capsule_pending(NULL)) { 606 pr_info("EFI capsule is pending, forcing EFI reboot.\n"); 607 reboot_type = BOOT_EFI; 608 } 609 610 for (;;) { 611 /* Could also try the reset bit in the Hammer NB */ 612 switch (reboot_type) { 613 case BOOT_ACPI: 614 acpi_reboot(); 615 reboot_type = BOOT_KBD; 616 break; 617 618 case BOOT_KBD: 619 mach_reboot_fixups(); /* For board specific fixups */ 620 621 for (i = 0; i < 10; i++) { 622 kb_wait(); 623 udelay(50); 624 outb(0xfe, 0x64); /* Pulse reset low */ 625 udelay(50); 626 } 627 if (attempt == 0 && orig_reboot_type == BOOT_ACPI) { 628 attempt = 1; 629 reboot_type = BOOT_ACPI; 630 } else { 631 reboot_type = BOOT_EFI; 632 } 633 break; 634 635 case BOOT_EFI: 636 efi_reboot(reboot_mode, NULL); 637 reboot_type = BOOT_BIOS; 638 break; 639 640 case BOOT_BIOS: 641 machine_real_restart(MRR_BIOS); 642 643 /* We're probably dead after this, but... */ 644 reboot_type = BOOT_CF9_SAFE; 645 break; 646 647 case BOOT_CF9_FORCE: 648 port_cf9_safe = true; 649 fallthrough; 650 651 case BOOT_CF9_SAFE: 652 if (port_cf9_safe) { 653 u8 reboot_code = reboot_mode == REBOOT_WARM ? 0x06 : 0x0E; 654 u8 cf9 = inb(0xcf9) & ~reboot_code; 655 outb(cf9|2, 0xcf9); /* Request hard reset */ 656 udelay(50); 657 /* Actually do the reset */ 658 outb(cf9|reboot_code, 0xcf9); 659 udelay(50); 660 } 661 reboot_type = BOOT_TRIPLE; 662 break; 663 664 case BOOT_TRIPLE: 665 idt_invalidate(); 666 __asm__ __volatile__("int3"); 667 668 /* We're probably dead after this, but... */ 669 reboot_type = BOOT_KBD; 670 break; 671 } 672 } 673 } 674 675 void native_machine_shutdown(void) 676 { 677 /* Stop the cpus and apics */ 678 #ifdef CONFIG_X86_IO_APIC 679 /* 680 * Disabling IO APIC before local APIC is a workaround for 681 * erratum AVR31 in "Intel Atom Processor C2000 Product Family 682 * Specification Update". In this situation, interrupts that target 683 * a Logical Processor whose Local APIC is either in the process of 684 * being hardware disabled or software disabled are neither delivered 685 * nor discarded. When this erratum occurs, the processor may hang. 686 * 687 * Even without the erratum, it still makes sense to quiet IO APIC 688 * before disabling Local APIC. 689 */ 690 clear_IO_APIC(); 691 #endif 692 693 #ifdef CONFIG_SMP 694 /* 695 * Stop all of the others. Also disable the local irq to 696 * not receive the per-cpu timer interrupt which may trigger 697 * scheduler's load balance. 698 */ 699 local_irq_disable(); 700 stop_other_cpus(); 701 #endif 702 703 lapic_shutdown(); 704 restore_boot_irq_mode(); 705 706 #ifdef CONFIG_HPET_TIMER 707 hpet_disable(); 708 #endif 709 710 #ifdef CONFIG_X86_64 711 x86_platform.iommu_shutdown(); 712 #endif 713 } 714 715 static void __machine_emergency_restart(int emergency) 716 { 717 reboot_emergency = emergency; 718 machine_ops.emergency_restart(); 719 } 720 721 static void native_machine_restart(char *__unused) 722 { 723 pr_notice("machine restart\n"); 724 725 if (!reboot_force) 726 machine_shutdown(); 727 __machine_emergency_restart(0); 728 } 729 730 static void native_machine_halt(void) 731 { 732 /* Stop other cpus and apics */ 733 machine_shutdown(); 734 735 tboot_shutdown(TB_SHUTDOWN_HALT); 736 737 stop_this_cpu(NULL); 738 } 739 740 static void native_machine_power_off(void) 741 { 742 if (kernel_can_power_off()) { 743 if (!reboot_force) 744 machine_shutdown(); 745 do_kernel_power_off(); 746 } 747 /* A fallback in case there is no PM info available */ 748 tboot_shutdown(TB_SHUTDOWN_HALT); 749 } 750 751 struct machine_ops machine_ops __ro_after_init = { 752 .power_off = native_machine_power_off, 753 .shutdown = native_machine_shutdown, 754 .emergency_restart = native_machine_emergency_restart, 755 .restart = native_machine_restart, 756 .halt = native_machine_halt, 757 #ifdef CONFIG_KEXEC_CORE 758 .crash_shutdown = native_machine_crash_shutdown, 759 #endif 760 }; 761 762 void machine_power_off(void) 763 { 764 machine_ops.power_off(); 765 } 766 767 void machine_shutdown(void) 768 { 769 machine_ops.shutdown(); 770 } 771 772 void machine_emergency_restart(void) 773 { 774 __machine_emergency_restart(1); 775 } 776 777 void machine_restart(char *cmd) 778 { 779 machine_ops.restart(cmd); 780 } 781 782 void machine_halt(void) 783 { 784 machine_ops.halt(); 785 } 786 787 #ifdef CONFIG_KEXEC_CORE 788 void machine_crash_shutdown(struct pt_regs *regs) 789 { 790 machine_ops.crash_shutdown(regs); 791 } 792 #endif 793 794 795 /* This is the CPU performing the emergency shutdown work. */ 796 int crashing_cpu = -1; 797 798 #if defined(CONFIG_SMP) 799 800 static nmi_shootdown_cb shootdown_callback; 801 802 static atomic_t waiting_for_crash_ipi; 803 static int crash_ipi_issued; 804 805 static int crash_nmi_callback(unsigned int val, struct pt_regs *regs) 806 { 807 int cpu; 808 809 cpu = raw_smp_processor_id(); 810 811 /* 812 * Don't do anything if this handler is invoked on crashing cpu. 813 * Otherwise, system will completely hang. Crashing cpu can get 814 * an NMI if system was initially booted with nmi_watchdog parameter. 815 */ 816 if (cpu == crashing_cpu) 817 return NMI_HANDLED; 818 local_irq_disable(); 819 820 shootdown_callback(cpu, regs); 821 822 atomic_dec(&waiting_for_crash_ipi); 823 /* Assume hlt works */ 824 halt(); 825 for (;;) 826 cpu_relax(); 827 828 return NMI_HANDLED; 829 } 830 831 /* 832 * Halt all other CPUs, calling the specified function on each of them 833 * 834 * This function can be used to halt all other CPUs on crash 835 * or emergency reboot time. The function passed as parameter 836 * will be called inside a NMI handler on all CPUs. 837 */ 838 void nmi_shootdown_cpus(nmi_shootdown_cb callback) 839 { 840 unsigned long msecs; 841 local_irq_disable(); 842 843 /* Make a note of crashing cpu. Will be used in NMI callback. */ 844 crashing_cpu = safe_smp_processor_id(); 845 846 shootdown_callback = callback; 847 848 atomic_set(&waiting_for_crash_ipi, num_online_cpus() - 1); 849 /* Would it be better to replace the trap vector here? */ 850 if (register_nmi_handler(NMI_LOCAL, crash_nmi_callback, 851 NMI_FLAG_FIRST, "crash")) 852 return; /* Return what? */ 853 /* 854 * Ensure the new callback function is set before sending 855 * out the NMI 856 */ 857 wmb(); 858 859 apic_send_IPI_allbutself(NMI_VECTOR); 860 861 /* Kick CPUs looping in NMI context. */ 862 WRITE_ONCE(crash_ipi_issued, 1); 863 864 msecs = 1000; /* Wait at most a second for the other cpus to stop */ 865 while ((atomic_read(&waiting_for_crash_ipi) > 0) && msecs) { 866 mdelay(1); 867 msecs--; 868 } 869 870 /* Leave the nmi callback set */ 871 } 872 873 /* 874 * Check if the crash dumping IPI got issued and if so, call its callback 875 * directly. This function is used when we have already been in NMI handler. 876 * It doesn't return. 877 */ 878 void run_crash_ipi_callback(struct pt_regs *regs) 879 { 880 if (crash_ipi_issued) 881 crash_nmi_callback(0, regs); 882 } 883 884 /* Override the weak function in kernel/panic.c */ 885 void nmi_panic_self_stop(struct pt_regs *regs) 886 { 887 while (1) { 888 /* If no CPU is preparing crash dump, we simply loop here. */ 889 run_crash_ipi_callback(regs); 890 cpu_relax(); 891 } 892 } 893 894 #else /* !CONFIG_SMP */ 895 void nmi_shootdown_cpus(nmi_shootdown_cb callback) 896 { 897 /* No other CPUs to shoot down */ 898 } 899 900 void run_crash_ipi_callback(struct pt_regs *regs) 901 { 902 } 903 #endif 904