In <200006230401.NAA31283@dec146.aist-nara.ac.jp>
nisimura@itc.aist-nara.ac.jp wrote:

> During stress test of tape drive access, my MAXINE paniced twice complaining
> "SCSI bus parity error".  Is it a hardware problem, or possible software
> driver implemention flaw?  The tape drive is TKZ15, rebadged EXB-85xx,
> and is running 2GB+ worth of data repeatedly.

I got the similar timeout report on tape access when I was developing
pcscp driver, which also uses MI ncr53c9x.
(It was not parity error, though.)

The problem on pcscp caused on handling of transfer pad operations.
When the situations occur, NCRDMA_SETUP() will be called
with *dmasize == 0. (See comments in ncr53c9x.c around line 2113)
I guess gl_dma_setup() in the glue code should handle this and
set the DMAC properly (or just return with no-op).

---
Izumi Tsutsui
tsutsui@ceres.dti.ne.jp