diff options
| -rw-r--r-- | arch/x86/kernel/reboot.c | 24 | ||||
| -rw-r--r-- | drivers/firmware/edd.c | 22 |
2 files changed, 34 insertions, 12 deletions
diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c index 08c44b08bf5b..0c016f727695 100644 --- a/arch/x86/kernel/reboot.c +++ b/arch/x86/kernel/reboot.c @@ -36,7 +36,7 @@ EXPORT_SYMBOL(pm_power_off); static const struct desc_ptr no_idt = {}; static int reboot_mode; -enum reboot_type reboot_type = BOOT_KBD; +enum reboot_type reboot_type = BOOT_ACPI; int reboot_force; #if defined(CONFIG_X86_32) && defined(CONFIG_SMP) @@ -478,9 +478,24 @@ void __attribute__((weak)) mach_reboot_fixups(void) { } +/* + * 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 + * + * 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 (4) we'll + * try to force a triple fault and then cycle between hitting the keyboard + * controller and doing that + */ static void native_machine_emergency_restart(void) { int i; + int attempt = 0; + int orig_reboot_type = reboot_type; if (reboot_emergency) emergency_vmx_disable_all(); @@ -502,6 +517,13 @@ static void native_machine_emergency_restart(void) outb(0xfe, 0x64); /* pulse reset low */ udelay(50); } + if (attempt == 0 && orig_reboot_type == BOOT_ACPI) { + attempt = 1; + reboot_type = BOOT_ACPI; + } else { + reboot_type = BOOT_TRIPLE; + } + break; case BOOT_TRIPLE: load_idt(&no_idt); diff --git a/drivers/firmware/edd.c b/drivers/firmware/edd.c index 96c25d93eed1..f1b7f659d3c9 100644 --- a/drivers/firmware/edd.c +++ b/drivers/firmware/edd.c @@ -531,8 +531,8 @@ static int edd_has_edd30(struct edd_device *edev) { struct edd_info *info; - int i, nonzero_path = 0; - char c; + int i; + u8 csum = 0; if (!edev) return 0; @@ -544,16 +544,16 @@ edd_has_edd30(struct edd_device *edev) return 0; } - for (i = 30; i <= 73; i++) { - c = *(((uint8_t *) info) + i + 4); - if (c) { - nonzero_path++; - break; - } - } - if (!nonzero_path) { + + /* We support only T13 spec */ + if (info->params.device_path_info_length != 44) + return 0; + + for (i = 30; i < info->params.device_path_info_length + 30; i++) + csum += *(((u8 *)&info->params) + i); + + if (csum) return 0; - } return 1; } |