On Tue, 28 Oct 2008, David Ross wrote:
My understanding was that a lot of DMA on the TT030 is to ST-ram, but the
SCSI DMA specifically does use TT-ram. Doing some quick digging, I
found:
http://www.vanc.igs.net/~roughley/overview.htm#SCSI
Which says:
"The TT's SCSI direct-memory-access subsystem can send and receive
information equally well, both from ST RAM and faster TT RAM, meaning
that present and future software will be able to exploit SCSI peripherals
efficiently."
There's a great archive of TT030 hardware info that may be useful as
well:
http://dev-docs.atariforge.org/html/search.php?find=_4
There is a comment in sys/arch/atari/dev/atari5380.c:
/*
* LWP: DMA transfers to TT-ram causes data to be garbled
* without notice on some TT-mainboard revisions.
* If programs generate mysterious Segmentations faults,
* try enabling NO_TTRAM_DMA.
*/
So, NetBSD is not currently using SCSI DMA to TT-ram.
I wonder if there is a way to query the mainboard revision so
NetBSD could selectively disable the DMA to TT-ram. David,
did you see any notes on DMA to TT-ram issues on earlier TT030s
in your searches? Does anyone else know?
As far as the DEBUG kernel below goes... On first boot I got a panic
after the boot message telling me the filesystem is clean. "Mutex error:
mutex_vector_enter: locking against myself" Then it had a few lines of
debug spew and "panic: lock error"
Thats not a good sign :/
So I rebooted (still with the same kernel) and now it's busy chugging
away validating the filesystem. Not sure if it will make it past that or
not. I've got to head off to sleep now so I'll report back with more info
tomorrow.
Thanks
I've been fixated on 1.6.1 for the last few months but now that the
kernel bug is fixed I want to check out 4.0 again. David, if you can
clarify what some of the "manual fixups" are that you mention are, that
would be very helpful. The next roadblock I'm aware of is the inability
to get the more recent installers to drop a working bootstrap on the
drive (or even upgrade an install that already has one).
And I second your call for some heroic developer to work on fixing up the
installer. =)
Well, I think a good first step would be to get a PR opened with
full details :)
--
David/absolute -- www.NetBSD.org: No hype required --