Re: i915+UEFI+Intel 9600M on Toshiba

[Jani Nikula <jani.nikula@linux.intel.com>]

On Fri, 10 Jan 2014, Cyrille Pontvieux <cyrille@enialis.net> wrote:
> I recently acquired a Toshiba laptop with a Intel Graphics 4600M in it
> (8086:0416, subsystem 1179:fa82).
> This Toshiba system is provided with UEFI (EFI Insyde H2O 1.30).
> I compiled and use Linux kernel 3.13-rc7 (config.gz attached)
> This system is provided with Windows 8.1 OS and the gpu is working fine
> under it.
> If I boot the laptop and Linux in BIOS compatible mode, gpu is working ok.
> If I boot the laptop and Linux in UEFI, there is strange problems on
> pixels rendering, both in the console (framebuffer) and in Xorg.
> The problem is that the colors are not "right" depending on the position
> of the pixel on the screen. For example, on white-on-black text, the
> white text is never rendered white but with an alternance of red, green,
> blue (cyan ?) and magenta pixels. If you look far enough, it looks
> white. There also appear to have maybe one pixel shifting or bluring,
> hard to tell.
> I also attached a photo to better explain the problem.
>
> The problem is exactly the same in framebuffer console or in Xorg.
> It appears early in the boot process. Before that the rendering is
> correct. Linux penguins are show correctly before a screen reset is done
> and the problem appears.
> I also attached the output of dmesg for that case.
>
> If I boot by disabling KMS (with nomodeset), the rendering is ok in
> Linux console, but I cannot run Xorg:
>    (EE) open /dev/dri/card0: No such file or directory
>    (EE) VESA(0): V_BIOS address 0x0 out of range
>    (EE) Screen(s) found, but none have a usable configuration.
> But maybe this is a separate problem and I need to compile newer intel
> Xorg drivers (mine is 2.21.15).
> I also attached the output of dmesg for that case.
>
> I could provide more input, or compile a custom/patched kernel to help
> correcting the problem.
> One more thing: contrary to what occurs recently with some i915 driver
> users, my gpu never hangs.

This bug is tracked at https://bugzilla.kernel.org/show_bug.cgi?id=68651


-- 
Jani Nikula, Intel Open Source Technology Center