vaseboot/VasEBoot-core/commands/i386/wrmsr.c

84 lines
2.5 KiB
C

/* wrmsr.c - Write CPU model-specific registers. */
/*
* VAS_EBOOT -- GRand Unified Bootloader
* Copyright (C) 2019 Free Software Foundation, Inc.
* Based on gcc/gcc/config/i386/driver-i386.c
*
* VAS_EBOOT 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.
*
* VAS_EBOOT 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 VAS_EBOOT. If not, see <http://www.gnu.org/licenses/>.
*/
#include <VasEBoot/dl.h>
#include <VasEBoot/misc.h>
#include <VasEBoot/mm.h>
#include <VasEBoot/env.h>
#include <VasEBoot/command.h>
#include <VasEBoot/extcmd.h>
#include <VasEBoot/lockdown.h>
#include <VasEBoot/i18n.h>
#include <VasEBoot/i386/cpuid.h>
#include <VasEBoot/i386/msr.h>
VAS_EBOOT_MOD_LICENSE("GPLv3+");
static VasEBoot_command_t cmd_write;
static VasEBoot_err_t
VasEBoot_cmd_msr_write (VasEBoot_command_t cmd __attribute__ ((unused)), int argc, char **argv)
{
VasEBoot_err_t err;
VasEBoot_uint32_t addr;
VasEBoot_uint64_t value;
const char *ptr;
err = VasEBoot_cpu_is_msr_supported ();
if (err != VAS_EBOOT_ERR_NONE)
return VasEBoot_error (err, N_("WRMSR is unsupported"));
if (argc != 2)
return VasEBoot_error (VAS_EBOOT_ERR_BAD_ARGUMENT, N_("two arguments expected"));
VasEBoot_errno = VAS_EBOOT_ERR_NONE;
ptr = argv[0];
addr = VasEBoot_strtoul (ptr, &ptr, 0);
if (VasEBoot_errno != VAS_EBOOT_ERR_NONE)
return VasEBoot_errno;
if (*ptr != '\0')
return VasEBoot_error (VAS_EBOOT_ERR_BAD_ARGUMENT, N_("invalid argument"));
ptr = argv[1];
value = VasEBoot_strtoull (ptr, &ptr, 0);
if (VasEBoot_errno != VAS_EBOOT_ERR_NONE)
return VasEBoot_errno;
if (*ptr != '\0')
return VasEBoot_error (VAS_EBOOT_ERR_BAD_ARGUMENT, N_("invalid argument"));
VasEBoot_wrmsr (addr, value);
return VAS_EBOOT_ERR_NONE;
}
VAS_EBOOT_MOD_INIT(wrmsr)
{
cmd_write = VasEBoot_register_command_lockdown ("wrmsr", VasEBoot_cmd_msr_write, N_("ADDR VALUE"),
N_("Write a value to a CPU model specific register."));
}
VAS_EBOOT_MOD_FINI(wrmsr)
{
VasEBoot_unregister_command (cmd_write);
}