diff options
Diffstat (limited to 'arch/x86/kernel/reboot.c')
| -rw-r--r-- | arch/x86/kernel/reboot.c | 262 |
1 files changed, 123 insertions, 139 deletions
diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c index d840e69a853c..25b48edb847c 100644 --- a/arch/x86/kernel/reboot.c +++ b/arch/x86/kernel/reboot.c @@ -24,6 +24,7 @@ #ifdef CONFIG_X86_32 # include <linux/ctype.h> # include <linux/mc146818rtc.h> +# include <asm/realmode.h> #else # include <asm/x86_init.h> #endif @@ -39,7 +40,8 @@ static int reboot_mode; enum reboot_type reboot_type = BOOT_ACPI; int reboot_force; -/* This variable is used privately to keep track of whether or not +/* + * This variable is used privately to keep track of whether or not * reboot_type is still set to its default value (i.e., reboot= hasn't * been set on the command line). This is needed so that we can * suppress DMI scanning for reboot quirks. Without it, it's @@ -51,7 +53,8 @@ static int reboot_default = 1; static int reboot_cpu = -1; #endif -/* This is set if we need to go through the 'emergency' path. +/* + * This is set if we need to go through the 'emergency' path. * When machine_emergency_restart() is called, we may be on * an inconsistent state and won't be able to do a clean cleanup */ @@ -60,22 +63,24 @@ static int reboot_emergency; /* This is set by the PCI code if either type 1 or type 2 PCI is detected */ bool port_cf9_safe = false; -/* reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old] | p[ci] - warm Don't set the cold reboot flag - cold Set the cold reboot flag - bios Reboot by jumping through the BIOS (only for X86_32) - smp Reboot by executing reset on BSP or other CPU (only for X86_32) - triple Force a triple fault (init) - kbd Use the keyboard controller. cold reset (default) - acpi Use the RESET_REG in the FADT - efi Use efi reset_system runtime service - pci Use the so-called "PCI reset register", CF9 - force Avoid anything that could hang. +/* + * reboot=b[ios] | s[mp] | t[riple] | k[bd] | e[fi] [, [w]arm | [c]old] | p[ci] + * warm Don't set the cold reboot flag + * cold Set the cold reboot flag + * bios Reboot by jumping through the BIOS (only for X86_32) + * smp Reboot by executing reset on BSP or other CPU (only for X86_32) + * triple Force a triple fault (init) + * kbd Use the keyboard controller. cold reset (default) + * acpi Use the RESET_REG in the FADT + * efi Use efi reset_system runtime service + * pci Use the so-called "PCI reset register", CF9 + * force Avoid anything that could hang. */ static int __init reboot_setup(char *str) { for (;;) { - /* Having anything passed on the command line via + /* + * Having anything passed on the command line via * reboot= will cause us to disable DMI checking * below. */ @@ -98,9 +103,11 @@ static int __init reboot_setup(char *str) if (isdigit(*(str+2))) reboot_cpu = reboot_cpu*10 + (int)(*(str+2) - '0'); } - /* we will leave sorting out the final value - when we are ready to reboot, since we might not - have detected BSP APIC ID or smp_num_cpu */ + /* + * We will leave sorting out the final value + * when we are ready to reboot, since we might not + * have detected BSP APIC ID or smp_num_cpu + */ break; #endif /* CONFIG_SMP */ @@ -150,6 +157,62 @@ static int __init set_bios_reboot(const struct dmi_system_id *d) return 0; } +void machine_real_restart(unsigned int type) +{ + void (*restart_lowmem)(unsigned int) = (void (*)(unsigned int)) + real_mode_header->machine_real_restart_asm; + + local_irq_disable(); + + /* + * Write zero to CMOS register number 0x0f, which the BIOS POST + * routine will recognize as telling it to do a proper reboot. (Well + * that's what this book in front of me says -- it may only apply to + * the Phoenix BIOS though, it's not clear). At the same time, + * disable NMIs by setting the top bit in the CMOS address register, + * as we're about to do peculiar things to the CPU. I'm not sure if + * `outb_p' is needed instead of just `outb'. Use it to be on the + * safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.) + */ + spin_lock(&rtc_lock); + CMOS_WRITE(0x00, 0x8f); + spin_unlock(&rtc_lock); + + /* + * Switch back to the initial page table. + */ + load_cr3(initial_page_table); + + /* + * Write 0x1234 to absolute memory location 0x472. The BIOS reads + * this on booting to tell it to "Bypass memory test (also warm + * boot)". This seems like a fairly standard thing that gets set by + * REBOOT.COM programs, and the previous reset routine did this + * too. */ + *((unsigned short *)0x472) = reboot_mode; + + /* Jump to the identity-mapped low memory code */ + restart_lowmem(type); +} +#ifdef CONFIG_APM_MODULE +EXPORT_SYMBOL(machine_real_restart); +#endif + +#endif /* CONFIG_X86_32 */ + +/* + * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot + */ +static int __init set_pci_reboot(const struct dmi_system_id *d) +{ + if (reboot_type != BOOT_CF9) { + reboot_type = BOOT_CF9; + printk(KERN_INFO "%s series board detected. " + "Selecting PCI-method for reboots.\n", d->ident); + } + return 0; +} + static int __init set_kbd_reboot(const struct dmi_system_id *d) { if (reboot_type != BOOT_KBD) { @@ -159,7 +222,12 @@ static int __init set_kbd_reboot(const struct dmi_system_id *d) return 0; } +/* + * This is a single dmi_table handling all reboot quirks. Note that + * REBOOT_BIOS is only available for 32bit + */ static struct dmi_system_id __initdata reboot_dmi_table[] = { +#ifdef CONFIG_X86_32 { /* Handle problems with rebooting on Dell E520's */ .callback = set_bios_reboot, .ident = "Dell E520", @@ -184,7 +252,7 @@ static struct dmi_system_id __initdata reboot_dmi_table[] = { DMI_MATCH(DMI_PRODUCT_NAME, "PowerEdge 300/"), }, }, - { /* Handle problems with rebooting on Dell Optiplex 745's SFF*/ + { /* Handle problems with rebooting on Dell Optiplex 745's SFF */ .callback = set_bios_reboot, .ident = "Dell OptiPlex 745", .matches = { @@ -192,7 +260,7 @@ static struct dmi_system_id __initdata reboot_dmi_table[] = { DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex 745"), }, }, - { /* Handle problems with rebooting on Dell Optiplex 745's DFF*/ + { /* Handle problems with rebooting on Dell Optiplex 745's DFF */ .callback = set_bios_reboot, .ident = "Dell OptiPlex 745", .matches = { @@ -201,7 +269,7 @@ static struct dmi_system_id __initdata reboot_dmi_table[] = { DMI_MATCH(DMI_BOARD_NAME, "0MM599"), }, }, - { /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */ + { /* Handle problems with rebooting on Dell Optiplex 745 with 0KW626 */ .callback = set_bios_reboot, .ident = "Dell OptiPlex 745", .matches = { @@ -210,7 +278,7 @@ static struct dmi_system_id __initdata reboot_dmi_table[] = { DMI_MATCH(DMI_BOARD_NAME, "0KW626"), }, }, - { /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */ + { /* Handle problems with rebooting on Dell Optiplex 330 with 0KP561 */ .callback = set_bios_reboot, .ident = "Dell OptiPlex 330", .matches = { @@ -219,7 +287,7 @@ static struct dmi_system_id __initdata reboot_dmi_table[] = { DMI_MATCH(DMI_BOARD_NAME, "0KP561"), }, }, - { /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */ + { /* Handle problems with rebooting on Dell Optiplex 360 with 0T656F */ .callback = set_bios_reboot, .ident = "Dell OptiPlex 360", .matches = { @@ -228,7 +296,7 @@ static struct dmi_system_id __initdata reboot_dmi_table[] = { DMI_MATCH(DMI_BOARD_NAME, "0T656F"), }, }, - { /* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G*/ + { /* Handle problems with rebooting on Dell OptiPlex 760 with 0G919G */ .callback = set_bios_reboot, .ident = "Dell OptiPlex 760", .matches = { @@ -301,7 +369,7 @@ static struct dmi_system_id __initdata reboot_dmi_table[] = { DMI_MATCH(DMI_PRODUCT_NAME, "SBC-FITPC2"), }, }, - { /* Handle problems with rebooting on ASUS P4S800 */ + { /* Handle problems with rebooting on ASUS P4S800 */ .callback = set_bios_reboot, .ident = "ASUS P4S800", .matches = { @@ -309,7 +377,9 @@ static struct dmi_system_id __initdata reboot_dmi_table[] = { DMI_MATCH(DMI_BOARD_NAME, "P4S800"), }, }, - { /* Handle reboot issue on Acer Aspire one */ +#endif /* CONFIG_X86_32 */ + + { /* Handle reboot issue on Acer Aspire one */ .callback = set_kbd_reboot, .ident = "Acer Aspire One A110", .matches = { @@ -317,96 +387,6 @@ static struct dmi_system_id __initdata reboot_dmi_table[] = { DMI_MATCH(DMI_PRODUCT_NAME, "AOA110"), }, }, - { } -}; - -static int __init reboot_init(void) -{ - /* Only do the DMI check if reboot_type hasn't been overridden - * on the command line - */ - if (reboot_default) { - dmi_check_system(reboot_dmi_table); - } - return 0; -} -core_initcall(reboot_init); - -extern const unsigned char machine_real_restart_asm[]; -extern const u64 machine_real_restart_gdt[3]; - -void machine_real_restart(unsigned int type) -{ - void *restart_va; - unsigned long restart_pa; - void (*restart_lowmem)(unsigned int); - u64 *lowmem_gdt; - - local_irq_disable(); - - /* Write zero to CMOS register number 0x0f, which the BIOS POST - routine will recognize as telling it to do a proper reboot. (Well - that's what this book in front of me says -- it may only apply to - the Phoenix BIOS though, it's not clear). At the same time, - disable NMIs by setting the top bit in the CMOS address register, - as we're about to do peculiar things to the CPU. I'm not sure if - `outb_p' is needed instead of just `outb'. Use it to be on the - safe side. (Yes, CMOS_WRITE does outb_p's. - Paul G.) - */ - spin_lock(&rtc_lock); - CMOS_WRITE(0x00, 0x8f); - spin_unlock(&rtc_lock); - - /* - * Switch back to the initial page table. - */ - load_cr3(initial_page_table); - - /* Write 0x1234 to absolute memory location 0x472. The BIOS reads - this on booting to tell it to "Bypass memory test (also warm - boot)". This seems like a fairly standard thing that gets set by - REBOOT.COM programs, and the previous reset routine did this - too. */ - *((unsigned short *)0x472) = reboot_mode; - - /* Patch the GDT in the low memory trampoline */ - lowmem_gdt = TRAMPOLINE_SYM(machine_real_restart_gdt); - - restart_va = TRAMPOLINE_SYM(machine_real_restart_asm); - restart_pa = virt_to_phys(restart_va); - restart_lowmem = (void (*)(unsigned int))restart_pa; - - /* GDT[0]: GDT self-pointer */ - lowmem_gdt[0] = - (u64)(sizeof(machine_real_restart_gdt) - 1) + - ((u64)virt_to_phys(lowmem_gdt) << 16); - /* GDT[1]: 64K real mode code segment */ - lowmem_gdt[1] = - GDT_ENTRY(0x009b, restart_pa, 0xffff); - - /* Jump to the identity-mapped low memory code */ - restart_lowmem(type); -} -#ifdef CONFIG_APM_MODULE -EXPORT_SYMBOL(machine_real_restart); -#endif - -#endif /* CONFIG_X86_32 */ - -/* - * Some Apple MacBook and MacBookPro's needs reboot=p to be able to reboot - */ -static int __init set_pci_reboot(const struct dmi_system_id *d) -{ - if (reboot_type != BOOT_CF9) { - reboot_type = BOOT_CF9; - printk(KERN_INFO "%s series board detected. " - "Selecting PCI-method for reboots.\n", d->ident); - } - return 0; -} - -static struct dmi_system_id __initdata pci_reboot_dmi_table[] = { { /* Handle problems with rebooting on Apple MacBook5 */ .callback = set_pci_reboot, .ident = "Apple MacBook5", @@ -474,17 +454,17 @@ static struct dmi_system_id __initdata pci_reboot_dmi_table[] = { { } }; -static int __init pci_reboot_init(void) +static int __init reboot_init(void) { - /* Only do the DMI check if reboot_type hasn't been overridden + /* + * Only do the DMI check if reboot_type hasn't been overridden * on the command line */ - if (reboot_default) { - dmi_check_system(pci_reboot_dmi_table); - } + if (reboot_default) + dmi_check_system(reboot_dmi_table); return 0; } -core_initcall(pci_reboot_init); +core_initcall(reboot_init); static inline void kb_wait(void) { @@ -502,14 +482,14 @@ static void vmxoff_nmi(int cpu, struct pt_regs *regs) cpu_emergency_vmxoff(); } -/* Use NMIs as IPIs to tell all CPUs to disable virtualization - */ +/* Use NMIs as IPIs to tell all CPUs to disable virtualization */ static void emergency_vmx_disable_all(void) { /* Just make sure we won't change CPUs while doing this */ local_irq_disable(); - /* We need to disable VMX on all CPUs before rebooting, otherwise + /* + * We need to disable VMX on all CPUs before rebooting, otherwise * we risk hanging up the machine, because the CPU ignore INIT * signals when VMX is enabled. * @@ -528,8 +508,7 @@ static void emergency_vmx_disable_all(void) * is still enabling VMX. */ if (cpu_has_vmx() && cpu_vmx_enabled()) { - /* Disable VMX on this CPU. - */ + /* Disable VMX on this CPU. */ cpu_vmxoff(); /* Halt and disable VMX on the other CPUs */ @@ -574,12 +553,12 @@ static void native_machine_emergency_restart(void) /* Could also try the reset bit in the Hammer NB */ switch (reboot_type) { case BOOT_KBD: - mach_reboot_fixups(); /* for board specific fixups */ + mach_reboot_fixups(); /* For board specific fixups */ for (i = 0; i < 10; i++) { kb_wait(); udelay(50); - outb(0xfe, 0x64); /* pulse reset low */ + outb(0xfe, 0x64); /* Pulse reset low */ udelay(50); } if (attempt == 0 && orig_reboot_type == BOOT_ACPI) { @@ -621,7 +600,7 @@ static void native_machine_emergency_restart(void) case BOOT_CF9: port_cf9_safe = true; - /* fall through */ + /* Fall through */ case BOOT_CF9_COND: if (port_cf9_safe) { @@ -659,9 +638,12 @@ void native_machine_shutdown(void) /* Make certain I only run on the appropriate processor */ set_cpus_allowed_ptr(current, cpumask_of(reboot_cpu_id)); - /* O.K Now that I'm on the appropriate processor, - * stop all of the others. + /* + * O.K Now that I'm on the appropriate processor, stop all of the + * others. Also disable the local irq to not receive the per-cpu + * timer interrupt which may trigger scheduler's load balance. */ + local_irq_disable(); stop_other_cpus(); #endif @@ -697,12 +679,11 @@ static void native_machine_restart(char *__unused) static void native_machine_halt(void) { - /* stop other cpus and apics */ + /* Stop other cpus and apics */ machine_shutdown(); tboot_shutdown(TB_SHUTDOWN_HALT); - /* stop this cpu */ stop_this_cpu(NULL); } @@ -713,7 +694,7 @@ static void native_machine_power_off(void) machine_shutdown(); pm_power_off(); } - /* a fallback in case there is no PM info available */ + /* A fallback in case there is no PM info available */ tboot_shutdown(TB_SHUTDOWN_HALT); } @@ -775,7 +756,8 @@ static int crash_nmi_callback(unsigned int val, struct pt_regs *regs) cpu = raw_smp_processor_id(); - /* Don't do anything if this handler is invoked on crashing cpu. + /* + * Don't do anything if this handler is invoked on crashing cpu. * Otherwise, system will completely hang. Crashing cpu can get * an NMI if system was initially booted with nmi_watchdog parameter. */ @@ -799,7 +781,8 @@ static void smp_send_nmi_allbutself(void) apic->send_IPI_allbutself(NMI_VECTOR); } -/* Halt all other CPUs, calling the specified function on each of them +/* + * Halt all other CPUs, calling the specified function on each of them * * This function can be used to halt all other CPUs on crash * or emergency reboot time. The function passed as parameter @@ -810,7 +793,7 @@ void nmi_shootdown_cpus(nmi_shootdown_cb callback) unsigned long msecs; local_irq_disable(); - /* Make a note of crashing cpu. Will be used in NMI callback.*/ + /* Make a note of crashing cpu. Will be used in NMI callback. */ crashing_cpu = safe_smp_processor_id(); shootdown_callback = callback; @@ -819,8 +802,9 @@ void nmi_shootdown_cpus(nmi_shootdown_cb callback) /* Would it be better to replace the trap vector here? */ if (register_nmi_handler(NMI_LOCAL, crash_nmi_callback, NMI_FLAG_FIRST, "crash")) - return; /* return what? */ - /* Ensure the new callback function is set before sending + return; /* Return what? */ + /* + * Ensure the new callback function is set before sending * out the NMI */ wmb(); |