[PATCH 0/2] Revive Amiga Zorro ESP SCSI driver

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At long last, revive the driver for m68k Amiga Zorro boards based on
the Qlogic ESP SCSI chip, which were in-tree as separate drivers
(blz1230.c, blz2060.c, cyberstorm.c, cyberstormII.c, fastlane.c) until
the rewrite of the ESP core code after 2.6.x.

A previous rewrite of the Zorro ESP SCSI drivers did not cope with tagged
commands, and needed an ugly workaround to disable tagged queueing. After
much poking around with config2 and config3 registers to no avail, the   
driver was never submitted.

Inspired by Finn Thain's PDMA fixes to the Mac ESP driver, the same strategy
of using PIO transfer for the short extended messages used to transfer the
queue tag was used for the Zorro driver. Evidently, the DMA engine on the
Zorro boards cannot handle short transfers of a few bytes only, and use of
PIO for these is the only option. 

I have decided to ignore checkpatch warnings about long lines and the use
of volatile in this patch - the long lines are due to excessive length
macros for Zorro board IDs defined elsewhere in the kernel. I have decided
to keep   volatile qualifiers for DMA engine registers because I found gcc   
to miscompile the DMA setup routines (omitting multiple register stores)
otherwise.




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