mmc: core: clear flags before allowing to retune

It might be that something goes wrong during tuning so the MMC core will
immediately trigger a retune. In our case it was:

 - we sent a tuning block
 - there was an error so we need to send an abort cmd to the eMMC
 - the abort cmd had a CRC error
 - retune was set by the MMC core

This lead to a vicious circle causing a performance regression of 75%.
So, clear retuning flags before we enable retuning to start with a known
cleared state.

Reported-by Yoshihiro Shimoda <[email protected]>
Suggested-by: Adrian Hunter <[email protected]>
Signed-off-by: Wolfram Sang <[email protected]>
Acked-by: Adrian Hunter <[email protected]>
Reviewed-by: Yoshihiro Shimoda <[email protected]>
Tested-by: Yoshihiro Shimoda <[email protected]>
Fixes: bd11e8bd03ca ("mmc: core: Flag re-tuning is needed on CRC errors")
Cc: [email protected]
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Ulf Hansson <[email protected]>

0 files changed, 0 insertions, 0 deletions