Re: Random hangs on 5.0 on R5000 Challenge S

["Stephen M. Rumble" <rumble%cs.stanford.edu@localhost>]

On Thu, Jul 09, 2009 at 01:57:27AM +0900, Izumi Tsutsui wrote:
> Last time I tried 5.0 on R5000 Indy, I saw some hangs.
> I have not tracked the problem, but R5000 O2 works fine
> so maybe there are some IP22/R5000 specific problems.
> (probably around wdsc SCSI?)

The only differences between 4.0 and 5.0 in wdsc are that the clock
is now correctly specified as 20MHz (was 10MHz), Burst DMA mode
is enabled, and Fast SCSI support was added.

Setting sc_clkfreq to 100 and sc_dmamode to SBIC_CTL_DMA in
sys/arch/sgimips/hpc/wdsc.c should essentially revert all of the above
and return to near NetBSD-4 behaviour.

There were also a fair number of Challenge-S related changes to
hpc/hpc.c, but it all used to work, at least.

Steve