scsi: hisi_sas: workaround v2 hw SATA IO timeout issue
authorXiang Chen <chenxiang66@hisilicon.com>
Fri, 20 Jan 2017 12:45:18 +0000 (20:45 +0800)
committerMartin K. Petersen <martin.petersen@oracle.com>
Sat, 21 Jan 2017 00:10:42 +0000 (19:10 -0500)
commitf2f89c32a0f1512856ffb4569bfdf2f20e42fcab
treeec89c66f2af855d169b5c999644348dc85bfdbc8
parente2934ed183b94cff7626a517877ecc9bbe82cdc8
scsi: hisi_sas: workaround v2 hw SATA IO timeout issue

The v2 SAS controller needs more time to detect channel idle
and send setup link request than SATA disk does, so it is
difficult for the SAS controller to setup an STP link. Therefore
it may cause some IO timeouts.

We need to periodically configure the SAS controller so it
doesn't receive STP setup requests from SATA disks for a while,
so IO can be sent during this period.

Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
drivers/scsi/hisi_sas/hisi_sas_v2_hw.c