Re: [PATCH 0/3] hisi_sas: device id/IPTT collision workaround

[Martin K. Petersen]

>>>>> "John" == John Garry <john.garry@xxxxxxxxxx> writes:

John> This patchset introduces a workaround to a hw quirk in the
John> HiSilicon SAS controller v2 hw.

John> The quirk is as follows: When a SATA and SAS frame arrives at the
John> host at the same time the frames may be swapped under this
John> condition: SATA device id bit [10:0] == SAS frame IPTT bit [10:0]
John> The workaround is to ensure these 2 values never match. The
John> workaround algorithm is as follows: - SATA device id bit0 always 0
John> - SATA IPTT has no restriction - SAS IPTT bit0 always 1 - SAS
John> device id has no restriction

John> The major restriction of this workaround is the SAS IPTT range is
John> halved, but this should be ok as testing has shown that even using
John> half the IPTT range does not affect performance.

Applied to 4.7/scsi-queue.

Thanks!

-- 
Martin K. Petersen	Oracle Linux Engineering