According to the eMMC specification, in Backwards Compatibility
with legacy MMC card mode, the frequency of the SD clock must be
0-26 MHZ; in high speed SDR mode, it must be 0-52MHZ. So we should
switch to high speed SDR mode if the clock frequency is higher than
26MHZ.
Signed-off-by: Yinzhe Wu <Yinzhe.Wu@sony.com>
Reviewed-by: Yuezhang Mo <Yuezhang.Mo@sony.com>
Reviewed-by: Jacky Cao <Jacky.Cao@sony.com>
Tested-by: Yinzhe Wu <Yinzhe.Wu@sony.com>