Need help untangling Xorg behavior on Haswell board, KMS, etc. etc.

[John Reynolds]

On 7/23/2013 4:00 AM, Niclas Zeising wrote:
> Hi!
>
> I'll try to answer all your questions below, as well as try to answer
> things from your follow-up mail.  Hopefully no confusion will arise.
thanks :)
> When buying/building computers based on new hardware, remember that it
> might take a little while before support for it shows up in FreeBSD.  In
> general most things work out of the box, but sometimes that is not the
> case.  I am not sure the Haswell GPU is supported by our graphics stack yet.
I had a feeling that might be the case when I was contemplating doing 
it--but I know things will eventually get fixed. :) ... plus I just came 
off a very difficult project and wanted to treat myself to some nice new 
hardware, the risks be damned :)
> In general, running without a xorg.conf should work, but there are a lot
> of different hardware and setups out there, and just because it works on
> Linux does not mean it works on FreeBSD without xorg.conf.  If you want
> to have more control of exactly what's going on, a config is probably to
> prefer.
OK
> KMS, or Kernel Mode Setting, is the "new" way of handling graphics in 
> X. basically a lot of stuff regarding the graphics card was previously 
> done in userland, however this makes it hard to get working graphics 
> acceleration and stuff, so a lot of this has moved into the kernel, 
> which means new kernel drivers are needed. An Intel KMS driver was 
> ported by kib@ and comitted a little over a year ago. Currently an 
> ATI/AMD KMS driver is under development, however it will take some 
> time before it is done. Without these drivers, we loose support for a 
> lot of modern hardware, which is part of the reason we have two xorg 
> distributions today. This new KMS driver isn't without some issues 
> though. Currently, when you enable it by loading the kld (which is 
> done when starting X) the VT console no longer works, since it doesn't 
> understand and support KMS. This is one of the reasons that the new 
> xorg distribution isn't the default. Once newcons is finished and 
> pushed into the FreeBSD source tree, the console should work with KMS. 
> This might be what you perceive as a lockup. 
yeah, it seems like it. One other person had mentioned it was the 
console code that needed to understand KMS. I
> Generally, it is possible to shut down the computer either from a 
> xterm (or other terminal emulator) or using the powerbutton once out 
> of X. However, there might be issues between the new graphics card and 
> FreeBSD that makes it hang. 
I can use the power button to take it down, but the filesystems are 
never shutdown properly when I do that for some reason. but with SU+J on 
the partitions now I haven't yet seen it not "fix itself" instantly upon 
boot.

> This is probably normal, it is looking for the graphics card device, 
> but can't find it. Either the kernel module didn't attached to the 
> graphics card, or it just shows up as a different device. What does 
> dmesg and kldstat say once you've started X?

kldstat did show the i915drm module as loaded, I remember .....

> Looking at this log, it seems that it first loads the intel driver, 
> but since that doesn't work, it falls back to using the VESA driver. 
> You can try to force the use of the intel driver in xorg.conf, 
> however, this might render your X unusable. I suggest you post your 
> dmesg and kldstat after you've started X, to see if the intel kms 
> kernel module is loaded and attached to the graphics card. It might 
> very well be that the current kernel driver doesn't support haswell. 
> Have you tried CURRENT as well? 
I have not tried -current yet. I generally have never run -current in 
the past except the transition from 4.x to 5.x briefly.....

I'm in the midst of reconfiguring the same machine (I made a boo boo in 
disk partitioning and needed to fix it and reinstall the whole ball of 
wax again) and will look at the dmesg output after I go into X (having 
it fallback to the VESA driver at this point of course).

Thanks for your reply!

-Jr