Ideally, optimal queue depth will be provided by firmware.  The driver
defines will be used as a fallback mechanism in case the FW assisted QD is
not supported.  The driver defined values provide optimal queue depth for
most of the drives and the workloads, as is learned from the firmware
assisted QD results.

Link: https://lore.kernel.org/r/1579000882-20246-4-git-send-email-anand.lodnoor@broadcom.comSigned-off-by: Chandrakanth Patil <chandrakanth.patil@broadcom.com>
Signed-off-by: Anand Lodnoor <anand.lodnoor@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>