scsi: mpt3sas: Handle RDPQ DMA allocation in same 4G region

For INVADER_SERIES, each set of 8 reply queues (0 - 7, 8 - 15,..), and for
VENTURA_SERIES, each set of 16 reply queues (0 - 15, 16 - 31,..) need to be
within the same 4 GB boundary. Driver uses limitation of VENTURA_SERIES to
manage INVADER_SERIES as well. The driver is allocating the DMA able
memory for RDPQs accordingly.

1) At driver load, set DMA mask to 64 and allocate memory for RDPQs

2) Check if allocated resources for RDPQ are in the same 4GB range

3) If #2 is true, continue with 64 bit DMA and go to #6

4) If #2 is false, then free all the resources from #1

5) Set DMA mask to 32 and allocate RDPQs

6) Proceed with driver loading and other allocations

Link: https://lore.kernel.org/r/1587626596-1044-5-git-send-email-suganath-prabu.subramani@broadcom.com
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Suganath Prabu <suganath-prabu.subramani@broadcom.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This commit is contained in:
Suganath Prabu 2020-04-23 03:23:15 -04:00 • committed by Martin K. Petersen
commit 8012209eb2
2 changed files with 109 additions and 46 deletions