From 650513979a437c32d7a0a84f0ed952a55bbb5583 Mon Sep 17 00:00:00 2001 From: "H. Peter Anvin" Date: Sat, 16 Jun 2012 21:47:37 -0700 Subject: x86-64, reboot: Allow reboot=bios and reboot-cpu override on x86-64 With the revamped realmode trampoline code, it is trivial to extend support for reboot=bios to x86-64. Furthermore, while we are at it, remove the restriction that only we can only override the reboot CPU on 32 bits. Signed-off-by: H. Peter Anvin Link: http://lkml.kernel.org/n/tip-jopx7y6g6dbcx4tpal8q0jlr@git.kernel.org --- arch/x86/kernel/reboot.c | 52 ++++++++++++++++++++++-------------------------- 1 file changed, 24 insertions(+), 28 deletions(-) (limited to 'arch/x86/kernel/reboot.c') diff --git a/arch/x86/kernel/reboot.c b/arch/x86/kernel/reboot.c index 25b48edb847..6ddb9cd0ced 100644 --- a/arch/x86/kernel/reboot.c +++ b/arch/x86/kernel/reboot.c @@ -20,14 +20,12 @@ #include #include #include +#include -#ifdef CONFIG_X86_32 -# include -# include -# include -#else -# include -#endif +#include +#include +#include +#include /* * Power off function, if any @@ -49,7 +47,7 @@ int reboot_force; */ static int reboot_default = 1; -#if defined(CONFIG_X86_32) && defined(CONFIG_SMP) +#ifdef CONFIG_SMP static int reboot_cpu = -1; #endif @@ -67,8 +65,8 @@ 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) + * bios Reboot by jumping through the BIOS + * smp Reboot by executing reset on BSP or other CPU * triple Force a triple fault (init) * kbd Use the keyboard controller. cold reset (default) * acpi Use the RESET_REG in the FADT @@ -95,7 +93,6 @@ static int __init reboot_setup(char *str) reboot_mode = 0; break; -#ifdef CONFIG_X86_32 #ifdef CONFIG_SMP case 's': if (isdigit(*(str+1))) { @@ -112,7 +109,6 @@ static int __init reboot_setup(char *str) #endif /* CONFIG_SMP */ case 'b': -#endif case 'a': case 'k': case 't': @@ -138,7 +134,6 @@ static int __init reboot_setup(char *str) __setup("reboot=", reboot_setup); -#ifdef CONFIG_X86_32 /* * Reboot options and system auto-detection code provided by * Dell Inc. so their systems "just work". :-) @@ -157,11 +152,8 @@ static int __init set_bios_reboot(const struct dmi_system_id *d) return 0; } -void machine_real_restart(unsigned int type) +void __noreturn machine_real_restart(unsigned int type) { - void (*restart_lowmem)(unsigned int) = (void (*)(unsigned int)) - real_mode_header->machine_real_restart_asm; - local_irq_disable(); /* @@ -181,7 +173,11 @@ void machine_real_restart(unsigned int type) /* * Switch back to the initial page table. */ +#ifdef CONFIG_X86_32 load_cr3(initial_page_table); +#else + write_cr3(real_mode_header->trampoline_pgd); +#endif /* * Write 0x1234 to absolute memory location 0x472. The BIOS reads @@ -192,14 +188,21 @@ void machine_real_restart(unsigned int type) *((unsigned short *)0x472) = reboot_mode; /* Jump to the identity-mapped low memory code */ - restart_lowmem(type); +#ifdef CONFIG_X86_32 + asm volatile("jmpl *%0" : : + "rm" (real_mode_header->machine_real_restart_asm), + "a" (type)); +#else + asm volatile("ljmpl *%0" : : + "m" (real_mode_header->machine_real_restart_asm), + "D" (type)); +#endif + unreachable(); } #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 */ @@ -223,11 +226,9 @@ static int __init set_kbd_reboot(const struct dmi_system_id *d) } /* - * This is a single dmi_table handling all reboot quirks. Note that - * REBOOT_BIOS is only available for 32bit + * This is a single dmi_table handling all reboot quirks. */ 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", @@ -377,7 +378,6 @@ static struct dmi_system_id __initdata reboot_dmi_table[] = { DMI_MATCH(DMI_BOARD_NAME, "P4S800"), }, }, -#endif /* CONFIG_X86_32 */ { /* Handle reboot issue on Acer Aspire one */ .callback = set_kbd_reboot, @@ -576,13 +576,11 @@ static void native_machine_emergency_restart(void) reboot_type = BOOT_KBD; break; -#ifdef CONFIG_X86_32 case BOOT_BIOS: machine_real_restart(MRR_BIOS); reboot_type = BOOT_KBD; break; -#endif case BOOT_ACPI: acpi_reboot(); @@ -624,12 +622,10 @@ void native_machine_shutdown(void) /* The boot cpu is always logical cpu 0 */ int reboot_cpu_id = 0; -#ifdef CONFIG_X86_32 /* See if there has been given a command line override */ if ((reboot_cpu != -1) && (reboot_cpu < nr_cpu_ids) && cpu_online(reboot_cpu)) reboot_cpu_id = reboot_cpu; -#endif /* Make certain the cpu I'm about to reboot on is online */ if (!cpu_online(reboot_cpu_id)) -- cgit v1.2.3-18-g5258