At least i.MX53 has errata ENGcm12360:

Occurs when a pending command which issues busy is completed.
For a command with R1b response, the proper software sequence
is to poll the DLA for R1b commands to determine busy
state completion. The DLA polling is not working properly for
the ESDHC module. This is relevant for all eSDHC ports (eSDHC1-4 ports)

DLA bit in PRSSTAT register cannot be
polled to wait for busy state completion.

Updated block guide to reflect that DLA is not applicable to detect
busy state, instead, should poll bit 24 in PRSSTAT register (DLSL[0] bit)
to check that wait busy state is over.

Signed-off-by: Markus Niebel <Markus.Niebel@tqs.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>