Subject: agp(4) vs. integrated graphics
To: None <tech-kern@netbsd.org>
From: Matthias Scheler <tron@zhadum.de>
List: tech-kern
Date: 08/28/2003 13:13:10
	Hello,

when booting NetBSD-current on my i865PE chipset based motherboard I get
these messages:

	pchb0: Intel 82865 Host (rev. 0x02)
	pchb0: random number generator enabled
-->	agp0 at pchb0: can't find internal VGA device config space
	ppb0 at pci0 dev 1 function 0: Intel 82865 AGP (rev. 0x02)
	pci1 at ppb0 bus 1
	pci1: i/o space, memory space enabled
	vga0 at pci1 dev 0 function 0: ATI Technologies Radeon 8500/8500LE (rev. 0x00)

The marked line is caused by "agp_i810.c" trying to find the integrated
graphics of an i865G chipset which doesn't exist on my motherboard. The
reason for that behaviour is that the i865's hostbridge is listed in
"agp.c" in "agp_products" like this:

#if NAGP_I810 > 0
[...]
        { PCI_VENDOR_INTEL,     PCI_PRODUCT_INTEL_82865_HB,
          NULL,                 agp_i810_attach },
[...]

So the problem is that i865PE and i865G use the same hostbridge while only
the i865G has a builtin graphics. The same problem probably affects the
i840 because its hostbridge is also listed in the above array.

What would be the correct fix? Just silently fail the i810 driver
attachment in case of i840/i865 chipset when the integrated graphics
is not found? Or is the attachment broken and should be fixed?

	Kind regards

-- 
Matthias Scheler                                  http://scheler.de/~matthias/