On Thu, 19 Mar 2009 16:13:14 +0000 Evgeniy Sudyr
<eject.in...@gmail.com> wrote:
> Hi, all I have problem with Xorg on -current. Card is supported (as I
> see) but X not startx :(.
>
> Look for my dmesg, xorg.conf and Xorg.0.log below and please let me
> know if there is a way to debug this problem.
>
>From your dmesg, log and conf (thanks!), I noticed you are attempting
to use drm (Direct Rendering Management) but have not yet created the
drm0 device.
# cd /dev
# ./MAKEDEV drm0
Though things can/should work without drm0, it's probably best to have
it set up properly.
There are a few issues with the new intel(4) driver. Many people
suggest changing from using the new default EXA acceleration to using
the old XAA acceleration.
Option "AccelMethod" "XAA"
Though some have had success with the above change to acceleration
method, the problems seem to be rooted a lot deeper, namely in the way
the VBIOS is understood and initialized, as well as the way the
attached display is queried and recognized.
> (WW) xf86ReadBIOS: /dev/mem mmap[s=600,a=0,o=0] failed (Invalid
> argument) (WW) Check that you have set 'machdep.allowaperture=2'
> in /etc/sysctl.conf and reboot your machine
> refer to xf86(4) for details
> (EE) intel(0): Cannot read int vect
> (EE) intel(0): Bad VBT signature
> (WW) intel(0): VBIOS initialization failed.
You need to make sure you've got the mentioned 'machdep.allowaperture=2'
in your /etc/sysctl.conf file or you'll have nothing but problems.
One of the things that has helped here is disabling the VESA Display
Data Channel (DDC) support. The DDC support is supposed to allow the
driver to figure out what the capabilities of the attached display, but
I've found at least two cases where this goes horribly wrong. There are
two version of DDC ("1" and "2"), and you can toggle support for them
on and off as follows:
Option "DDC" "false" # shut off all DDC
Option "DDC1" "false" # shut off version 1
Option "DDC2" "false" # shut off version 2
I shut off the latter ("DDC2") on some i845 boxes here and it solves
most all of the problems.
Though DDC might seem "too simple" to be the problem, you need to
understand that the new intel(4) driver has it's own wild idea about
"correct" resolution and refresh of your display, and THE DRIVER OFTEN
IGNORES WHAT YOU TELL IT TO DO in your xorg.conf
The reason why the new intel(4) driver has a mind of it's own when it
comes to "correct" display settings is due to the fact that many LCD's
have "fixed" or "native" display settings. The intel(4) driver tries
to rescale your xorg.conf display settings into something the LCD will
actually accept. More details can be found in the intel(4) man page.
By shutting off DCC, and thereby preventing the driver from learning
anything about the attached display, you've prevented the driver from
doing this (uncontrolled) rescaling nonsense.
--
J.C. Roberts
