Subject: ..about SCSI disconnect..
To: David Jones <dej@eecg.toronto.edu>
From: Jukka Marin <jmarin@muikku.jmp.fi>
List: amiga
Date: 03/28/1995 08:52:05
> > Does -current?  If so, this is certainly good enough reason to
> > upgrade.
> 
> Nope.
> 
> The problem is DMA: when a device disconnects, can you accurately determine
> how much DMA was done, flush the DMA and FIFO, then restart it?
> 
> What if the device disconnects on a non-longword boundary?
> 
> Anybody got DMAC docs?

Is this an A3000 only problem?  Ie. has disconnect/reselect been implemented
in other NetBSD kernels (say, the one for Sparcs)?

Has anyone tried to disassemble the AmigaOS scsi.device - it handles
everything beautifully.

(Now that I'm whining again, does -current have dynamic disk buffers?  I
believe they would improve disk IO speed remarkably.  Currently, an SS1 is
7 times as fast in real-world disk IO as A3000/NetBSD.  Sigh.)

  -jm