Re: Fwd: Re: Macbook Pro Retina display problems

[Daniel Vetter <daniel@ffwll.ch>]

On Thu, Aug 02, 2012 at 01:37:05PM +1000, Francois Rigaut wrote:
> Dave, Greg,
> 
> OK, the problem was indeed a connection issue. By using gfxcardstatus
> within osx, I was able to force the HD4000 to connect to the display.
> The xorg log now reports:
> 
> [     8.226] (--) PCI:*(0:0:2:0) 8086:0166:106b:00f7 rev 9, Mem @ 0xc1400000/4194304, 0xb0000000/268435456, I/O @ 0x00003000/64
> [     8.226] (--) PCI: (0:1:0:0) 10de:0fd5:106b:00f2 rev 161, Mem @ 0xc0000000/16777216, 0x90000000/268435456, 0xa0000000/33554432, I/O @ 0x00002000/128, BIOS @ 0x????????/524288
> 
> instead of greg's (or mine, prior to forcing with gfxcardstatus):
> 
> [   224.406] (--) PCI: (0:0:2:0) 8086:0166:106b:00f7 rev 9, Mem @ 0xc1400000/4194304, 0xb0000000/268435456, I/O @ 0x00003000/64
> [   224.406] (--) PCI:*(0:1:0:0) 10de:0fd5:106b:00f2 rev 161, Mem @ 0xc0000000/16777216, 0x90000000/268435456, 0xa0000000/33554432, I/O @ 0x00002000/128, BIOS @ 0x????????/524288
> 
> I assume the star indicates to which pci the display is connected.
> 
> The laptop now boots ok (with kms) and X starts without any error.
> I can change modes and have checked that it effectively changes the
> resolution. It is accelerated. Everything looks ok except that the
> display is quite corrupted (at any resolution).
> 
> Some elements:
> 
> * The display is the new retina display, 2880x1800; quite a bit of
> pixels to push (might be related to the problem, see below). I'm using
> the 3.5.0 kernel with everything stock.
> 
> * I thought initially that i915 was not getting the correct EDID from
> the display and tried forcing the EDID with drm_kms_helper (using
> stock 1920x1080 and the edid.bin I extracted when using the laptop
> with the discrete nvidia card + nvidia blob), but it didn't help at
> all; same display corruption.
> 
> * I have a dump of dmesg (using drmd.debug=6) and xorg log at
> http://maumae.net/retina/intel_corrupted_drm_debug/dmesg_intel_drm_debug

I get 404 on the dmesg.

> and
> http://maumae.net/retina/intel_corrupted_drm_debug/xorg_log_intel_corrupted_drm_debug
> The xorg log doesn't report any error. The modeline used looks
> allright to me
> [    9.856125] [drm:drm_mode_debug_printmodeline], Modeline 17:"2880x1800" 60 337750 2880 2928 2960 3040 1800 1803 1809 1852 0x48 0x9
> 
> * Ryan Bourgeois is working on a similar corruption issue for the
> nouveau driver. He claims that this might actually be related to a
> link bandwidth problem:
> "This line right here out of your dmesg:
>    DP link bw 0a lane count 4 clock 270000 bpp 24
> That's part of the DP link training and it's configuring it the same
> way as nouveau does, four lanes at 2.7Gbps. So if it is an issue with
> the Retina exceeding that bandwidth it's consistent across both devices.
> The link is configured based on the mode and panel capabilities, so
> that makes sense.
> I still need to try a couple of things to validate whether or not this
> is the situation."
> (last quotes from https://bbs.archlinux.org/viewtopic.php?id=144255&p=2).
> 
> * I can't show you what the corruption looks like, as when I take
> screenshots (with xfce4-screenshooter), they do NOT show the
> corruption (there are some in
> http://maumae.net/retina/intel_corrupted_drm_debug/ ). I guess this
> means the image is ok in video memory, the corruption occurs when it's
> pushed to the display, kind of pointing to the link bandwidth again.

Hm, can you take a picture with a camera? Also, is the corruption static
when nothing should change on the screen, or does it flicker?
-Daniel
-- 
Daniel Vetter
Mail: daniel@ffwll.ch
Mobile: +41 (0)79 365 57 48