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Diffstat (limited to '')
-rw-r--r-- | grub-core/commands/i386/pc/halt.c | 126 |
1 files changed, 126 insertions, 0 deletions
diff --git a/grub-core/commands/i386/pc/halt.c b/grub-core/commands/i386/pc/halt.c new file mode 100644 index 0000000..1e7c2c9 --- /dev/null +++ b/grub-core/commands/i386/pc/halt.c @@ -0,0 +1,126 @@ +/* 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); +} |