mac_scsi: Fix pseudo DMA implementation

Fix various issues: Comments about bus errors are incorrect. The
PDMA asm must return the size of the memory access that faulted so the
transfer count can be adjusted accordingly. A phase change may cause a
bus error but should not be treated as failure. A bus error does not
always imply a phase change and generally the transfer may continue.
Scatter/gather doesn't seem to work with PDMA due to overruns. This is
a pity because peak throughput seems to double with SG_ALL.
Tested on a Mac LC III and a PowerBook 520.

Signed-off-by: Finn Thain <[email protected]>
Reviewed-by: Hannes Reinecke <[email protected]>
Signed-off-by: Martin K. Petersen <[email protected]>

0 files changed, 0 insertions, 0 deletions