Re: Kernels w/o DRM{,2} also missing support for "agpgart".

[christos%astron.com@localhost (Christos Zoulas)]

In article <Pine.NEB.4.64.1411042246300.424%david.technoskunk.fur@localhost>,
John D. Baker <jdbaker%mylinuxisp.com@localhost> wrote:
>In the past, my custom kernels for my i82810e-based machines have disabled
>all drm{,2} support since none has ever been built for these chips
>anyway.  The intel driver for Xorg worked in spite of this (except for
>stippled regions being rendered as solid black, but that's a compiler
>issue).
>
>I was recently able to boot an up-to-date -current kernel on one of
>these systems and was dismayed to discover that the X server now complained
>about lack of "agpgart" support.  A GENERIC kernel (in which drm2/kms
>is now default) allowed the X server to operate as normal.  The
>i82810e-based machines retain the VGA text-mode console.
>
>My custom kernel merely includes "GENERIC" and disables unwanted
>drivers/subsystems with the "no foo at bar" facility--the relevant
>items being the "i915drmkms" and "intelfb" drivers.
>
>Now, I must have "i915drmkms" included included to get "agpgart" support
>(the legacy "i915drm" driver is not sufficient) where before no drm
>driver was needed.

There is a problem with the agp config rules. This will perhaps fix it
for you:

Index: files.pci
===================================================================
RCS file: /cvsroot/src/sys/arch/x86/pci/files.pci,v
retrieving revision 1.18
diff -u -r1.18 files.pci
--- files.pci   18 Oct 2014 16:56:51 -0000      1.18
+++ files.pci   5 Nov 2014 13:23:10 -0000
@@ -12,7 +12,7 @@
 define amdnb_miscbus {}
 
 # PCI-Host bridge chipsets
-device pchb:   pcibus, agpbus
+device pchb:   pcibus, agpbus, agp_x86
 attach pchb at pci
 file   arch/x86/pci/pchb.c             pchb            needs-flag