Re: [Openvortex-dev] VIA fix?

[Ryan Underwood]

Hi,

On Mon, Aug 11, 2003 at 03:53:48AM -0500, Seg wrote:
> > This fix works by adjusting the bit called ?Extend PCI#2 Internal Master
> > for Efficient Handling of Dummy Requests? for the register ?PCI #2
> > Master Control? of the AGP controller in VIA north-bridges.  This should
> > be enabled for the best Vortex 2 compatibility on VIA motherboards.  The
> > default setting in the chip itself if Disabled, and the BIOS must set
> > this to 1, as per VIA?s recommendations.  Unfortunately, some
> > manufacturers don?t and hence you have to set in the follwing way.
> > 
> > <snip generic WCPREDIT instructions>
> > 
> > Type this in: Bus 0, Device 1, Function 0.  And, for Register put in 42
> > and in Data add 10 to the current value.
> > 
> > The link is here but it can also be dug up from the google cache:
> > http://myweb.tiscali.co.uk/chris.day/vortexfix00.html
> > 
> > setpci should also do that, just `setpci -d '12eb:*' 42.B` to get the
> > value, and `setpci -d '12eb:*' 42.B new_value` to set the value,
> > where new_value is the value that was read + 10.
> 
> Okay, I just tried messing with this. I don't understand this +10 stuff.
> On my system it defaults to 0x80, I tried setting it +10, 0x8a in hex,
> still hangs immediately. So I try counting down from FF, and at 0xfe it
> still hangs. It seems the higher the value, the longer it lasts. At 0xfe
> it will manage to play for maybe 15 seconds, then hang.

Well, what he means by "adding 10" is "set bit 5 of the register high".
To do that starting with 0x80, it would become 0x90.  This register
is a configuration register, so simply putting a higher value in it
would not have the same effect as the PCI latency register.

-- 
Ryan Underwood, <nemesis at icequake.net>, icq=10317253