mtrr setup?

[David A. Bandel]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On Thu, 9 Jan 2003 11:56:35 -0500
begin  Douglas J Hunley <doug at linux-sxs.org> spewed forth:

> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
> 
> David A. Bandel spewed electrons into the ether that resembled:
> > > reg00: base=0x00000000 ( 0MB), size=2048MB; write-back, count=1
> >
> > you have 2Gb of memory?
> 
> yep :)
> 
> > reg00: base=0x00000000 (   0MB), size= 256MB: write-back, count=1
> > reg01: base=0xe4000000 (3648MB), size=  64MB: write-combining, count=1
> > reg02: base=0xdc000000 (3520MB), size=   4MB: write-combining, count=1
> >
> > IIRC, you can only have one write-back entry, the rest will be
> > write-combining.  Do you have other entries?  Those others are the
> > ones
> 
> what I pasted is the only entry

Then that is definitely non-optimal.  But your X driver for your video
card should be setting these parameters.  The reg01 entry above is my PCI
host bridge (entry from /proc/iomem):
e4000000-e47fffff : PCI device 1106:3112 (VIA Technologies, Inc.)

and from /proc/pci:
  Bus  0, device   0, function  0:
    Host bridge: PCI device 1106:3112 (VIA Technologies, Inc.) (rev 0).
      Master Capable.  Latency=8.  
      Prefetchable 32 bit memory at 0xe4000000 [0xe47fffff].

Not sure what the dc000000 entry is, but since my video card (onboard) is
4Mb, that should be it.  But these are all set up by drivers that know how
to use mtrr.  The docs suggest that that's what supposed to happen, so I
haven't exactly worried about it before since it "looks" right.

If you don't have an entry that seems to match your video card's memory,
it's almost certainly not optimized.  What version of X are you running? 
Perhaps you need to upgrade?  Or maybe a quick note to the driver's author
is in line?

Ciao,

David A. Bandel
- -- 
Focus on the dream, not the competition.
		-- Nemesis Racing Team motto
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.1 (GNU/Linux)

iD8DBQE+HuBR3uVcotqGMQcRAuyeAKCWd6DGXO2MCDEse/Ft6PYz+io0NwCfZpaL
AhnA06kuBFbM/TRrzhwPOPA=
=adby
-----END PGP SIGNATURE-----