scsi: ufs: core: Poll HCS.UCRDY before issuing a UIC command
authorKiwoong Kim <kwmad.kim@samsung.com>
Mon, 4 Sep 2023 01:30:45 +0000 (10:30 +0900)
committerMartin K. Petersen <martin.petersen@oracle.com>
Tue, 5 Sep 2023 10:10:24 +0000 (06:10 -0400)
commitd32533d30e2119b0c0aa17596734f1f842f750df
treee5009c3e8dde3944537d16af4f493e74273392f5
parent2d3f59cf868b4a2dd678a96cd49bdd91411bd59f
scsi: ufs: core: Poll HCS.UCRDY before issuing a UIC command

With auto hibern8 enabled, UIC could be busy processing a hibern8 operation
and the HCI would reports UIC not ready for a short while through
HCS.UCRDY. The UFS driver doesn't currently handle this situation. The
UFSHCI spec specifies UCRDY like this: whether the host controller is ready
to process UIC COMMAND

The 'ready' could be seen as many different meanings. If the meaning
includes not processing any request from HCI, processing a hibern8
operation can be 'not ready'. In this situation, the driver needs to wait
until the operations is completed.

Signed-off-by: Kiwoong Kim <kwmad.kim@samsung.com>
Link: https://lore.kernel.org/r/550484ffb66300bdcec63d3e304dfd55cb432f1f.1693790060.git.kwmad.kim@samsung.com
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Reviewed-by: Chanwoo Lee <cw9316.lee@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
drivers/ufs/core/ufshcd.c