Home built kernel causes minor XF68_FBDev problems.

[Peter Canning <canning@nospam.vitria.com>]

I've been running the 2.2.12 kernel from
ftp://ftp.linuxppc.org/kernels/vmlinux-2.2.12.gz, for several months,
and
it has worked great with my debian installation.  Unfortunately, when I
tried to run MOL, I discovered that I didn't have a System.map
cooresponding to that kernel, and I couldn't find one anywhere.  I tried
installing the 2.2.12 kernel-image deb and copying to the MacOS side for
BootX, but it didn't seem to be configured quite right for my machine (I
can't remember exactly what was wrong). As a result, I figure it was
about
time to build my own kernel.  I've done it before in the MkLinux world,
but
this is my first attempt in the debian universe.  I installed the
kernel-doc-2.2.12, kernel-package, kernel-patch-2.2.12-powerpc, and
kernel-source-2.2.12, and followed the instructions in
/usr/doc/kernel-package to configure, build, install, and boot the new
kernel.  Everything works great (including MOL), except that with the
old
2.2.12 kernel I'm was using, X would come up in 1600x1200 resolution
(and I
could switch to other resolutions with ctrl-alt-keypad +/-).  With the
kernel I built, it comes up in ??? resolution, but I can still switch to
other resolutions the same way.  However, I'm curious what I've done
wrong
that it doesn't work the same.  I looked at /var/log/xdm.log, and
discovered I'm getting different output depending on which kernel I use.
Here is a diff of the changes (the < file is the original kernel, and
the >
file is the kernel I built):

27,33c27,29
< (--) FBDev: Removing mode "800x600" from list of valid
modes.
< (--) FBDev: Removing mode "1024x768" from list of valid modes.
<
(--) FBDev: Removing mode "1152x864" from list of valid modes.
< (--)
FBDev: Removing mode "1280x1024" from list of valid modes.
< (--) FBDev:
Frame buffer device: OFfb ATY,XCLAIM
< (--) FBDev: Video memory: 3750K @
0x81800480
< (--) FBDev: MMIO regs: 0K @ (nil)
---
> (--) FBDev: Frame
buffer device: ATY Mach64
> (--) FBDev: Video memory: 4092K @ 0x81800000
>
(--) FBDev: MMIO regs: 2K @ 0x817ff800
35,36c31
< (--) FBDev: Hardware
accelerator: None
< (--) FBDev: No driver support for hardware
acceleration
---
> (--) FBDev: Hardware accelerator: ATI Mach64GT (3D
RAGE)
37a33,35
> (--) FBDev: Initializing accel code
> (**) FBDev: Pixmap
cache disabled
> (**) FBDev: Font cache disabled
38a37
> mach64CreateGC:
unsupported depth: 16. Using cfbCreateGC instead.
39a39,65
>
mach64CreateGC: unsupported depth: 16. Using cfbCreateGC instead.
>
mach64CreateGC: unsupported depth: 16. Using cfbCreateGC instead.

There are 25 more lines like the last two.  I'm pretty suspicious of the
differences between the Frame buffer device, Video memory, and MMIO regs
lines.

I'm also a little surprised to see "Hardware accelerator: None" when
using
the original kernel.  Both xdm.log files say: "Using cfb16 driver".

So after this long explaination, can anybody tell me what is going on?
Have I screwed something up in cofiguring my kernel?

	thanks,
	Peter Canning -- remove nospam. from my address to reply

PS: Here's the final section of my XF86Config (in case it is relevant):

Section "Screen"
    Driver      "fbdev"
    Device      "ATY Mach64"
    Monitor     "Apple Vision 850 AV Display"
    DefaultColorDepth	16
    Subsection "Display"
        Depth       8
        Modes       "640x480" "800x600" "1024x768" "1152x864"
"1280x1024"
        ViewPort    0 0
        Virtual     1280 1024
    EndSubsection
    Subsection "Display"
        Depth       16
        Modes       "800x600" "1024x768" "1152x864" "1280x1024"
"1600x1200"
        ViewPort    0 0
        Virtual     1600 1200
    EndSubsection
    Subsection "Display"
        Depth       32
        Modes       "640x480" "800x600" "1024x768"
        ViewPort    0 0
        Virtual     1024 768
    EndSubsection
EndSection