diff options
| -rw-r--r-- | arch/x86/kernel/reboot.c | 72 | ||||
| -rw-r--r-- | include/linux/reboot.h | 14 |
2 files changed, 44 insertions, 42 deletions
diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c index 654b46574b91..3399d3a99730 100644 --- a/arch/x86/kernel/reboot.c +++ b/arch/x86/kernel/reboot.c @@ -114,8 +114,8 @@ EXPORT_SYMBOL(machine_real_restart); */ static int __init set_pci_reboot(const struct dmi_system_id *d) { - if (reboot_type != BOOT_CF9) { - reboot_type = BOOT_CF9; + if (reboot_type != BOOT_CF9_FORCE) { + reboot_type = BOOT_CF9_FORCE; pr_info("%s series board detected. Selecting %s-method for reboots.\n", d->ident, "PCI"); } @@ -458,20 +458,23 @@ void __attribute__((weak)) mach_reboot_fixups(void) } /* - * Windows compatible x86 hardware expects the following on reboot: + * To the best of our knowledge Windows compatible x86 hardware expects + * the following on reboot: * * 1) If the FADT has the ACPI reboot register flag set, try it * 2) If still alive, write to the keyboard controller * 3) If still alive, write to the ACPI reboot register again * 4) If still alive, write to the keyboard controller again * 5) If still alive, call the EFI runtime service to reboot - * 6) If still alive, write to the PCI IO port 0xCF9 to reboot - * 7) If still alive, inform BIOS to do a proper reboot + * 6) If no EFI runtime service, call the BIOS to do a reboot * - * If the machine is still alive at this stage, it gives up. We default to - * following the same pattern, except that if we're still alive after (7) we'll - * try to force a triple fault and then cycle between hitting the keyboard - * controller and doing that + * We default to following the same pattern. We also have + * two other reboot methods: 'triple fault' and 'PCI', which + * can be triggered via the reboot= kernel boot option or + * via quirks. + * + * This means that this function can never return, it can misbehave + * by not rebooting properly and hanging. */ static void native_machine_emergency_restart(void) { @@ -492,6 +495,11 @@ static void native_machine_emergency_restart(void) for (;;) { /* Could also try the reset bit in the Hammer NB */ switch (reboot_type) { + case BOOT_ACPI: + acpi_reboot(); + reboot_type = BOOT_KBD; + break; + case BOOT_KBD: mach_reboot_fixups(); /* For board specific fixups */ @@ -509,43 +517,29 @@ static void native_machine_emergency_restart(void) } break; - case BOOT_TRIPLE: - load_idt(&no_idt); - __asm__ __volatile__("int3"); - - /* We're probably dead after this, but... */ - reboot_type = BOOT_KBD; - break; - - case BOOT_BIOS: - machine_real_restart(MRR_BIOS); - - /* We're probably dead after this, but... */ - reboot_type = BOOT_TRIPLE; - break; - - case BOOT_ACPI: - acpi_reboot(); - reboot_type = BOOT_KBD; - break; - case BOOT_EFI: if (efi_enabled(EFI_RUNTIME_SERVICES)) efi.reset_system(reboot_mode == REBOOT_WARM ? EFI_RESET_WARM : EFI_RESET_COLD, EFI_SUCCESS, 0, NULL); - reboot_type = BOOT_CF9_COND; + reboot_type = BOOT_BIOS; + break; + + case BOOT_BIOS: + machine_real_restart(MRR_BIOS); + + /* We're probably dead after this, but... */ + reboot_type = BOOT_CF9_SAFE; break; - case BOOT_CF9: + case BOOT_CF9_FORCE: port_cf9_safe = true; /* Fall through */ - case BOOT_CF9_COND: + case BOOT_CF9_SAFE: if (port_cf9_safe) { - u8 reboot_code = reboot_mode == REBOOT_WARM ? - 0x06 : 0x0E; + u8 reboot_code = reboot_mode == REBOOT_WARM ? 0x06 : 0x0E; u8 cf9 = inb(0xcf9) & ~reboot_code; outb(cf9|2, 0xcf9); /* Request hard reset */ udelay(50); @@ -553,7 +547,15 @@ static void native_machine_emergency_restart(void) outb(cf9|reboot_code, 0xcf9); udelay(50); } - reboot_type = BOOT_BIOS; + reboot_type = BOOT_TRIPLE; + break; + + case BOOT_TRIPLE: + load_idt(&no_idt); + __asm__ __volatile__("int3"); + + /* We're probably dead after this, but... */ + reboot_type = BOOT_KBD; break; } } diff --git a/include/linux/reboot.h b/include/linux/reboot.h index 9e7db9e73cc1..48bf152761c7 100644 --- a/include/linux/reboot.h +++ b/include/linux/reboot.h @@ -20,13 +20,13 @@ enum reboot_mode { extern enum reboot_mode reboot_mode; enum reboot_type { - BOOT_TRIPLE = 't', - BOOT_KBD = 'k', - BOOT_BIOS = 'b', - BOOT_ACPI = 'a', - BOOT_EFI = 'e', - BOOT_CF9 = 'p', - BOOT_CF9_COND = 'q', + BOOT_TRIPLE = 't', + BOOT_KBD = 'k', + BOOT_BIOS = 'b', + BOOT_ACPI = 'a', + BOOT_EFI = 'e', + BOOT_CF9_FORCE = 'p', + BOOT_CF9_SAFE = 'q', }; extern enum reboot_type reboot_type; |