--- zzzz-none-000/linux-4.4.60/drivers/mmc/core/mmc.c	2017-04-08 07:53:53.000000000 +0000
+++ wasp-540e-714/linux-4.4.60/drivers/mmc/core/mmc.c	2019-07-03 09:21:34.000000000 +0000
@@ -1131,6 +1131,15 @@
 	mmc_set_timing(host, MMC_TIMING_MMC_HS400);
 	mmc_set_bus_speed(card);
 
+	if ((host->caps2 & MMC_CAP2_HS400_POST_TUNING) &&
+			host->ops->execute_tuning) {
+		err = host->ops->execute_tuning(host,
+				MMC_SEND_TUNING_BLOCK_HS200);
+		if (err)
+			pr_warn("%s: post tuning execution failed\n",
+					mmc_hostname(host));
+	}
+
 	if (!send_status) {
 		err = mmc_switch_status(card);
 		if (err)