Comment 2 for bug 1497472

the bug is resolved in official kernel, proper 5.0 emmc support is added see mmc.c:

/* eMMC v5 or later */
 if (card->ext_csd.rev >= 7) {
  memcpy(card->ext_csd.fwrev, &ext_csd[EXT_CSD_FIRMWARE_VERSION],
         MMC_FIRMWARE_LEN);
  card->ext_csd.ffu_capable =
   (ext_csd[EXT_CSD_SUPPORTED_MODE] & 0x1) &&
   !(ext_csd[EXT_CSD_FW_CONFIG] & 0x1);

  card->ext_csd.pre_eol_info = ext_csd[EXT_CSD_PRE_EOL_INFO];
  card->ext_csd.device_life_time_est_typ_a =
   ext_csd[EXT_CSD_DEVICE_LIFE_TIME_EST_TYP_A];
  card->ext_csd.device_life_time_est_typ_b =
   ext_csd[EXT_CSD_DEVICE_LIFE_TIME_EST_TYP_B];
 }

Please support flo again! :)