cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
Log | Files | Refs | README | LICENSE | sfeed.txt

reboot.c (1823B)

      1// SPDX-License-Identifier: GPL-2.0
      2/*
      3 * Copyright (C) 2014 Intel Corporation; author Matt Fleming
      4 * Copyright (c) 2014 Red Hat, Inc., Mark Salter <msalter@redhat.com>
      5 */
      6#include <linux/efi.h>
      7#include <linux/reboot.h>
      8
      9static void (*orig_pm_power_off)(void);
     10
     11int efi_reboot_quirk_mode = -1;
     12
     13void efi_reboot(enum reboot_mode reboot_mode, const char *__unused)
     14{
     15	const char *str[] = { "cold", "warm", "shutdown", "platform" };
     16	int efi_mode, cap_reset_mode;
     17
     18	if (!efi_rt_services_supported(EFI_RT_SUPPORTED_RESET_SYSTEM))
     19		return;
     20
     21	switch (reboot_mode) {
     22	case REBOOT_WARM:
     23	case REBOOT_SOFT:
     24		efi_mode = EFI_RESET_WARM;
     25		break;
     26	default:
     27		efi_mode = EFI_RESET_COLD;
     28		break;
     29	}
     30
     31	/*
     32	 * If a quirk forced an EFI reset mode, always use that.
     33	 */
     34	if (efi_reboot_quirk_mode != -1)
     35		efi_mode = efi_reboot_quirk_mode;
     36
     37	if (efi_capsule_pending(&cap_reset_mode)) {
     38		if (efi_mode != cap_reset_mode)
     39			printk(KERN_CRIT "efi: %s reset requested but pending "
     40			       "capsule update requires %s reset... Performing "
     41			       "%s reset.\n", str[efi_mode], str[cap_reset_mode],
     42			       str[cap_reset_mode]);
     43		efi_mode = cap_reset_mode;
     44	}
     45
     46	efi.reset_system(efi_mode, EFI_SUCCESS, 0, NULL);
     47}
     48
     49bool __weak efi_poweroff_required(void)
     50{
     51	return false;
     52}
     53
     54static void efi_power_off(void)
     55{
     56	efi.reset_system(EFI_RESET_SHUTDOWN, EFI_SUCCESS, 0, NULL);
     57	/*
     58	 * The above call should not return, if it does fall back to
     59	 * the original power off method (typically ACPI poweroff).
     60	 */
     61	if (orig_pm_power_off)
     62		orig_pm_power_off();
     63}
     64
     65static int __init efi_shutdown_init(void)
     66{
     67	if (!efi_rt_services_supported(EFI_RT_SUPPORTED_RESET_SYSTEM))
     68		return -ENODEV;
     69
     70	if (efi_poweroff_required()) {
     71		orig_pm_power_off = pm_power_off;
     72		pm_power_off = efi_power_off;
     73	}
     74
     75	return 0;
     76}
     77late_initcall(efi_shutdown_init);