src/drivers/vpd/vpd_device_feature.c

   1 /* SPDX-License-Identifier: GPL-2.0-only */
   2
   3 #include <b64_decode.h>
   4 #include <console/console.h>
   5 #include <drivers/vpd/vpd.h>
   6 #include <stdlib.h>
   7
   8 #define VPD_KEY_FEATURE_DEVICE_INFO     "feature_device_info"
   9
  10 /*
  11  * Extracts the "feature_level" from the "feature_device_info" VPD key.
  12  * This key holds a base64-encoded protobuf where "feature_level" is the first entry.
  13  */
  14 uint8_t vpd_get_feature_level(void)
  15 {
  16         const uint8_t *device_info;
  17         int device_info_size, feature_level = 0;
  18         uint8_t *decoded_device_info;
  19         size_t decoded_size;
  20
  21         device_info = vpd_find(VPD_KEY_FEATURE_DEVICE_INFO, &device_info_size, VPD_RW);
  22         if (!device_info)
  23                 return feature_level;
  24
  25         decoded_size = B64_DECODED_SIZE(device_info_size);
  26         decoded_device_info = malloc(decoded_size);
  27         if (!decoded_device_info) {
  28                 printk(BIOS_ERR, "%s: failed allocating %zd bytes\n", __func__, decoded_size);
  29                 return feature_level;
  30         }
  31
  32         /* The index 1 of the decoded data is the "feature level" value */
  33         if (b64_decode(device_info, device_info_size, decoded_device_info))
  34                 feature_level = decoded_device_info[1];
  35
  36         free(decoded_device_info);
  37         return feature_level;
  38 }