diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c
index 68f5f4ba57e9..e2e1dd40fb11 100644
--- a/drivers/mmc/core/core.c
+++ b/drivers/mmc/core/core.c
@@ -1753,7 +1753,7 @@ void mmc_init_erase(struct mmc_card *card)
 		card->erase_shift = ffs(card->ssr.au) - 1;
 	} else if (card->ext_csd.hc_erase_size) {
 		card->pref_erase = card->ext_csd.hc_erase_size;
-	} else {
+	} else if (card->erase_size) {
 		sz = (card->csd.capacity << (card->csd.read_blkbits - 9)) >> 11;
 		if (sz < 128)
 			card->pref_erase = 512 * 1024 / 512;
@@ -1770,7 +1770,8 @@ void mmc_init_erase(struct mmc_card *card)
 			if (sz)
 				card->pref_erase += card->erase_size - sz;
 		}
-	}
+	} else
+		card->pref_erase = 0;
 }
 
 static unsigned int mmc_mmc_erase_timeout(struct mmc_card *card,