mmc: core: changes frequency to hs_max_dtr when selecting hs400es

Per JESD84-B51 P49, Host need to change frequency to <=52MHz
after setting HS_TIMING to 0x1, and host may changes frequency
to <= 200MHz after setting HS_TIMING to 0x3. That means the card
expects the clock rate to increase from the current used f_init
(which is less than 400KHz, but still being less than 52MHz) to
52MHz, otherwise we find some eMMC devices significantly report
failure when sending status.
Reported-by: NXiao Yao <xiaoyao@rock-chips.com>
Signed-off-by: NShawn Lin <shawn.lin@rock-chips.com>
Reviewed-by: NDouglas Anderson <dianders@chromium.org>
Signed-off-by: NUlf Hansson <ulf.hansson@linaro.org>

drivers/mmc/core/mmc.c

@@ -1282,6 +1282,8 @@ static int mmc_select_hs400es(struct mmc_card *card)
 	if (err)
 		goto out_err;
 
+	mmc_set_clock(host, card->ext_csd.hs_max_dtr);
+
 	err = mmc_switch_status(card);
 	if (err)
 		goto out_err;