Re: ide.2.4.1-p3.01112001.patch

[Jamie Lokier]

> > Note that "hdparm -X34 -d1" enables old DMA, not UDMA.  (The board was
> > advertised as UDMA capable but it isn't AFAIK).

Fwiw, -X34 does not fix the lockups for everyone else.

Vojtech Pavlik wrote:
> Is the board still available for some testing?

The board is not in the same country as me (Wales vs. France), but I
visit it every few months so there is some chance of me testing it on
that timescale.  AFAIK there are no computer experts in the area to
enable remote access ;-)

> It should be able to do UDMA33.

It does not look hopeful.  Let us look at an old email:

From: Jamie Lokier <[e-mail]>
To: Michel Aubry <[e-mail]>
Subject: Re: mozilla+XFree86+Linux-2.1.x  => HARD LOCKUP (addition)

On Wed, Dec 09, 1998 at 04:30:34PM +0100, Michel Aubry wrote:
> Is this to say that your bios has no "select UDMA" or so capability???
> Is your motherboard an old one? (that was not udma compliant).

It has "Bus Master DMA" option, but no "UDMA" option.  It's an FIC
PC-2011, manufactured about August 1997.  I always assumed the hardware
did UDMA (that's one reason I bought it).

>       you should edit via82c586.c , uncomment or add a 
> "#define DISPLAY_VIA_TIMINGS"
>       and recompile your kernel...

Will do, at my next recompile.  Would that be with the patch you sent me?

> You ought to know that linux kernel via patch requires your bios to be
> udma compliant. If not, all you can do safely is run it dma only!

Is this strictly true?  You've obviously got all the chipset docs, and I
doubt anything on the motherboard interferes with IDE timings/state
machines.

> > [root@tantalophile linux]# hdparm -I /dev/hda

>       this one is not running udma!

I know, I did hdparm -X34 explicitly to avoid lockups.

> > [root@tantalophile linux]# hdparm -i /dev/hda
> 
>       this one is running udma!

And with these settings unchanged, the system locks up from time to
time.

-- Jamie