Subject: Re: pciide performance on alpha
To: Andreas Johansson <firstname.lastname@example.org>
From: Manuel Bouyer <email@example.com>
Date: 08/13/1999 11:14:49
On Thu, Aug 12, 1999 at 10:57:07PM +0200, Andreas Johansson wrote:
> Yep, it seems to work as good as I had hoped - I think this disk is also
> maxed out with modest cpu usage:
> ajo@ymer /home/ajo #time dd if=/dev/rwd0c of=/dev/null bs=64k count=8192
> 8192+0 records in
> 8192+0 records out
> 536870912 bytes transferred in 34 secs (15790320 bytes/sec)
> 0.033u 1.550s 0:34.44 4.5% 0+0k 0+0io 0pf+0w
Nice drive !
> > Do you have the BIOS ROM on your board ? If so try to remove it.
> > Maybe the alpha firmare tries to run it (with i386 emulation, as it is done
> > for VGA) and it gets this really wrong.
> It seems that the pci registers had been changed in software while I was
> trying to get things to work - I coldbooted the machine, and the channels
> were enabled without me having to force-enable them.
Ok, that is consistent with the infos I have - at power-on the board is
> Now only the problem with bad I/O addresses remain. This is what I get
> (and change) in my SX at boot time. I have to take back that about
> overlapping addresses, I was masking too much (different masks for
> mem/io). It seems the firmware simply thinks that IO addresses above
> 0x10000 are ok (which they probably are in the alpha), but NetBSD wraps IO
> addresses higher than 0xffff. If I don't change the IO addresses, I get a
> machine check as quick as the driver is accessing the registers.
If adresses above 0xffff are ok on the alpha (Jason, is this true ? You know
alpha hardware better than me :) then NetBSD certainly does the rigth thing
(otherwise a lot of other drivers would fail as well).
My guess is that the promise chip, which was specifically designed for
PCs, doesn't support it.
Manuel Bouyer, LIP6, Universite Paris VI. Manuel.Bouyer@lip6.fr