Re: DMA past and present

Bernhard Kaindl (bartelt@computerhaus.at)
Sat, 15 Jun 1996 22:27:48 +0200 (MET DST)


On Sat, 15 Jun 1996, Steve VanDevender wrote:

> Quitting DOOM would
> get me a message like "DMA timed out -- IRQ/DRQ conflict?" But as far
> as I could tell, there was no IRQ conflict, and my GUS was the only
> device that used DMA.

As far as I know, linux-doom's soundserver uses 16bit DMA normally, and
I've also have such problems when trying to do 16bit WAV-playback with
my AHA-1542. I think there are some difficulties with two 16bit DMA
transfers at the same time, but I don't know the exact source of it.

Does someone know more?

Bernhard

>
> Recently I finally achieved the Holy Grail for my old but serviceable
> ISA-bus system -- a working BusLogic BT-545C to plug a Fujitsu 1G SCSI
> disk into. And it works -- almost. But it has symptoms that at least
> at one level seem analogous to the GUS problem -- it gets SCSI timeouts
> with messages like this:
>
> Jun 15 00:52:18 tzadkiel linux: scsi : aborting command due to timeout : pid 26423, scsi0, channel 0, id 0, lun 0 Read (6) 00 80 32 02 00
> Jun 15 00:52:23 tzadkiel linux: scsi0: Aborting CCB #26437 to Target 0
> Jun 15 00:52:23 tzadkiel linux: scsi : aborting command due to timeout : pid 26424, scsi0, channel 0, id 0, lun 0 Read (6) 06 20 22 08 00
> Jun 15 00:52:23 tzadkiel linux: scsi0: Aborting CCB #26438 to Target 0
> Jun 15 00:52:23 tzadkiel linux: SCSI host 0 abort (pid 26423) timed out - resetting
> Jun 15 00:52:23 tzadkiel linux: SCSI bus is being reset for host 0 channel 0.
> Jun 15 00:52:23 tzadkiel linux: scsi0: Sending Bus Device Reset CCB #26439 to Target 0
> Jun 15 00:52:23 tzadkiel linux: SCSI host 0 abort (pid 26424) timed out - resetting
> Jun 15 00:52:23 tzadkiel linux: SCSI bus is being reset for host 0 channel 0.
> Jun 15 00:52:23 tzadkiel linux: scsi0: Resetting BusLogic BT-54xC due to Target 0
> Jun 15 00:52:23 tzadkiel linux: scsi0: *** BusLogic BT-54xC Initialized Successfully ***
>

+-----------------------------------------------------------------------+
| Bernhard Kaindl, Tallak 95, 8103 Rein, Austria |
| Autor of kmenu, first kernel config tool for linux w/ automatic menus |
+-----------------------------------------------------------------------+