Garbled display on iMac (Radeon HD 6750M)

[jonas.kirilla]

The desktop comes up garbled with hrev43238 (gcc2hybrid, nightly image) on an iMac.

  Chipset Model:	AMD Radeon HD 6750M
  Type:	GPU
  Bus:	PCIe
  PCIe Lane Width:	x16
  VRAM (Total):	512 MB
  Vendor:	ATI (0x1002)
  Device ID:	0x6741
  Revision ID:	0x0000
  ROM Revision:	113-C2950H-170
  EFI Driver Version:	01.00.544
  Displays:

iMac:
  Resolution:	1920 x 1080
  Pixel Depth:	32-Bit Color (ARGB8888)
  Main Display:	Yes
  Mirror:	Off
  Online:	Yes
  Built-In:	Yes
  Connection Type:	DisplayPort

[kallisti5]

Definitely looks like a pixel clock issue.

The iMac's have lots of special unicorn one-off adjustments (many of which I haven't ported over yet)

This plus the display port is kind of a double whammy. Could we get the system logs from the boot attempt? You may be able to press and hold ctl+alt+delete for 4 seconds once the system loads to force a clean shutdown / reboot which will ensure the syslogs (/common/var/log/syslog) are written to your boot disk. (which I hope is a USB stick and not a CD)

[kallisti5]

Potentially due to #8329

[kallisti5]

hrev43767 should resolve this issue so the native resolution should be set properly.

Can you test as soon as you have access to a hrev43767 or higher build?

[jonas.kirilla]

I tested with hrev43768 and the blue of the desktop wouldn't show up at all. Just a flash of white and then black.

FWIW: Mac OS X calls it an "AMD Radeon HD 6750M 512 MB" whereas Haiku thinks it's either HD 6600M or 6650M.

[jonas.kirilla]

Syslog and listdev added.

[kallisti5]

syslogs don't show radeon_hd being loaded... could you try again?

[kallisti5]

try post hrev43810. hrev43810 fixes a *big* oops.

[jonas.kirilla]

No change with hrev43810. Just a brief fully white screen and then black.

[kallisti5]

lol.. sigh. I have the exact same card now in my testing arsenal... and it works.

​http://twitpic.com/8rhd3e

I'm still betting this one is due to the iMac one-offs needed. I'll see if I can figure something out.

Exactly what kind of iMac is this?

[jonas.kirilla]

The model identifier is "iMac12,1". It's the 21.5 inch one from summer 2011. (Core i5, 2,5 GHz)

Some info from OS X: (Translated from Swedish.)

AMD Radeon HD 6750M:

  Circuit model:	AMD Radeon HD 6750M
  Type:	Videoprocessor
  Bus:	PCIe
  PCIe-bandwidth:	x16
  VRAM (total):	512 MB
  Maker:	ATI (0x1002)
  Unit-ID:	0x6741
  Revision-ID:	0x0000
  ROM-revision:	113-C2950H-170
  EFI-driverversion:	01.00.544
 
 Monitors:
iMac:
  Resolution:	1920 x 1080
  Color depth:	32 bit color (ARGB8888)
  Primary screen:	Yes
  Screen doubling:	Off
  Connected:	Yes
  Built-in:	Yes
  Connection:	DisplayPort

So maybe it's the internal DisplayPort connection that's different. Or something related to EFI.

[kallisti5]

try hrev43900... it solves several garbled screen issues.

Let me know your results :)

[jonas.kirilla]

No visual change.

The bug report title is wrong though; there is no garbledness to be seen, as the screen goes black, as it has done for quite some time. I'm starting to doubt whether the attached garbled screenshot is driven by radeon or, if possible, a shot of garbled vesa that I mistook for radeon.