drivers/firmware/efi/reboot.c

   1 /*
   2  * Copyright (C) 2014 Intel Corporation; author Matt Fleming
   3  * Copyright (c) 2014 Red Hat, Inc., Mark Salter <msalter@redhat.com>
   4  */
   5 #include <linux/efi.h>
   6 #include <linux/reboot.h>
   7
   8 int efi_reboot_quirk_mode = -1;
   9
  10 void efi_reboot(enum reboot_mode reboot_mode, const char *__unused)
  11 {
  12         const char *str[] = { "cold", "warm", "shutdown", "platform" };
  13         int efi_mode, cap_reset_mode;
  14
  15         if (!efi_enabled(EFI_RUNTIME_SERVICES))
  16                 return;
  17
  18         switch (reboot_mode) {
  19         case REBOOT_WARM:
  20         case REBOOT_SOFT:
  21                 efi_mode = EFI_RESET_WARM;
  22                 break;
  23         default:
  24                 efi_mode = EFI_RESET_COLD;
  25                 break;
  26         }
  27
  28         /*
  29          * If a quirk forced an EFI reset mode, always use that.
  30          */
  31         if (efi_reboot_quirk_mode != -1)
  32                 efi_mode = efi_reboot_quirk_mode;
  33
  34         if (efi_capsule_pending(&cap_reset_mode)) {
  35                 if (efi_mode != cap_reset_mode)
  36                         printk(KERN_CRIT "efi: %s reset requested but pending "
  37                                "capsule update requires %s reset... Performing "
  38                                "%s reset.\n", str[efi_mode], str[cap_reset_mode],
  39                                str[cap_reset_mode]);
  40                 efi_mode = cap_reset_mode;
  41         }
  42
  43         efi.reset_system(efi_mode, EFI_SUCCESS, 0, NULL);
  44 }
  45
  46 bool __weak efi_poweroff_required(void)
  47 {
  48         return false;
  49 }
  50
  51 static void efi_power_off(void)
  52 {
  53         efi.reset_system(EFI_RESET_SHUTDOWN, EFI_SUCCESS, 0, NULL);
  54 }
  55
  56 static int __init efi_shutdown_init(void)
  57 {
  58         if (!efi_enabled(EFI_RUNTIME_SERVICES))
  59                 return -ENODEV;
  60
  61         if (efi_poweroff_required())
  62                 pm_power_off = efi_power_off;
  63
  64         return 0;
  65 }
  66 late_initcall(efi_shutdown_init);