| /* halt.c - command to halt the computer. */ |
| /* |
| * GRUB -- GRand Unified Bootloader |
| * Copyright (C) 2005,2007,2009 Free Software Foundation, Inc. |
| * |
| * GRUB is free software: you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation, either version 3 of the License, or |
| * (at your option) any later version. |
| * |
| * GRUB is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| * GNU General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with GRUB. If not, see <http://www.gnu.org/licenses/>. |
| */ |
| |
| #include <grub/dl.h> |
| #include <grub/misc.h> |
| #include <grub/extcmd.h> |
| #include <grub/i18n.h> |
| #include <grub/machine/int.h> |
| #include <grub/acpi.h> |
| |
| GRUB_MOD_LICENSE ("GPLv3+"); |
| |
| static const struct grub_arg_option options[] = |
| { |
| {"no-apm", 'n', 0, N_("Do not use APM to halt the computer."), 0, 0}, |
| {0, 0, 0, 0, 0, 0} |
| }; |
| |
| static inline void __attribute__ ((noreturn)) |
| stop (void) |
| { |
| while (1) |
| { |
| asm volatile ("hlt"); |
| } |
| } |
| /* |
| * Halt the system, using APM if possible. If NO_APM is true, don't use |
| * APM even if it is available. |
| */ |
| void __attribute__ ((noreturn)) |
| grub_halt (int no_apm) |
| { |
| struct grub_bios_int_registers regs; |
| |
| grub_acpi_halt (); |
| |
| if (no_apm) |
| stop (); |
| |
| /* detect APM */ |
| regs.eax = 0x5300; |
| regs.ebx = 0; |
| regs.flags = GRUB_CPU_INT_FLAGS_DEFAULT; |
| grub_bios_interrupt (0x15, ®s); |
| |
| if (regs.flags & GRUB_CPU_INT_FLAGS_CARRY) |
| stop (); |
| |
| /* disconnect APM first */ |
| regs.eax = 0x5304; |
| regs.ebx = 0; |
| regs.flags = GRUB_CPU_INT_FLAGS_DEFAULT; |
| grub_bios_interrupt (0x15, ®s); |
| |
| /* connect APM */ |
| regs.eax = 0x5301; |
| regs.ebx = 0; |
| regs.flags = GRUB_CPU_INT_FLAGS_DEFAULT; |
| grub_bios_interrupt (0x15, ®s); |
| if (regs.flags & GRUB_CPU_INT_FLAGS_CARRY) |
| stop (); |
| |
| /* set APM protocol level - 1.1 or bust. (this covers APM 1.2 also) */ |
| regs.eax = 0x530E; |
| regs.ebx = 0; |
| regs.ecx = 0x0101; |
| regs.flags = GRUB_CPU_INT_FLAGS_DEFAULT; |
| grub_bios_interrupt (0x15, ®s); |
| if (regs.flags & GRUB_CPU_INT_FLAGS_CARRY) |
| stop (); |
| |
| /* set the power state to off */ |
| regs.eax = 0x5307; |
| regs.ebx = 1; |
| regs.ecx = 3; |
| regs.flags = GRUB_CPU_INT_FLAGS_DEFAULT; |
| grub_bios_interrupt (0x15, ®s); |
| |
| /* shouldn't reach here */ |
| stop (); |
| } |
| |
| static grub_err_t __attribute__ ((noreturn)) |
| grub_cmd_halt (grub_extcmd_context_t ctxt, |
| int argc __attribute__ ((unused)), |
| char **args __attribute__ ((unused))) |
| |
| { |
| struct grub_arg_list *state = ctxt->state; |
| int no_apm = 0; |
| |
| if (state[0].set) |
| no_apm = 1; |
| grub_halt (no_apm); |
| } |
| |
| static grub_extcmd_t cmd; |
| |
| GRUB_MOD_INIT(halt) |
| { |
| cmd = grub_register_extcmd ("halt", grub_cmd_halt, 0, "[-n]", |
| N_("Halt the system, if possible using APM."), |
| options); |
| } |
| |
| GRUB_MOD_FINI(halt) |
| { |
| grub_unregister_extcmd (cmd); |
| } |