src/drivers/efi/option.c

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 #include <option.h>
   4 #include <smmstore.h>
   5
   6 #include <Uefi/UefiBaseType.h>
   7
   8 #include "efivars.h"
   9
  10 static const EFI_GUID EficorebootNvDataGuid = {
  11         0xceae4c1d, 0x335b, 0x4685, { 0xa4, 0xa0, 0xfc, 0x4a, 0x94, 0xee, 0xa0, 0x85 } };
  12
  13 unsigned int get_uint_option(const char *name, const unsigned int fallback)
  14 {
  15         struct region_device rdev;
  16         enum cb_err ret;
  17         uint32_t var;
  18         uint32_t size;
  19
  20         if (smmstore_lookup_region(&rdev))
  21                 return fallback;
  22
  23         var = 0;
  24         size = sizeof(var);
  25         ret = efi_fv_get_option(&rdev, &EficorebootNvDataGuid, name, &var, &size);
  26         if (ret != CB_SUCCESS)
  27                 return fallback;
  28
  29         return var;
  30 }
  31
  32 enum cb_err set_uint_option(const char *name, unsigned int value)
  33 {
  34         struct region_device rdev;
  35         uint32_t var = value;
  36
  37         if (smmstore_lookup_region(&rdev))
  38                 return CB_CMOS_OTABLE_DISABLED;
  39
  40         return efi_fv_set_option(&rdev, &EficorebootNvDataGuid, name, &var, sizeof(var));
  41 }