Bug reports on 830MG patches (thanks, but more trouble)

Thomas Richter
2014-06-05T21:34:02Z

Update on the 830MG Updates:

As Ville already said, resume from "suspend-to-ram" is broken. No
surprise, old broken bios. However, there is a big difference between
the kernel with the pipe-A quirk disabled, and the one with pipe-a and
pipe-b quirks enabled: If resumed without the quirk, the display is
dead, but you can at least re-initiate it with vbetool post, then
restart the X server. So at least, the kernel is working.

With the pipe A quirk enabled, something dies immediately when
attempting to resume from suspend. The machine is completely
unresponsive, also not reachable over the network. The kernel dies away.
This is *probably* related to the dying kernel when booting with vga=792
(or vga=791 or vga=790, all cause the same problem, no working machine.)

----

Thanks for the patch and for all the work, unfortunately it does not
quite work as presented. I applied the patch correctly to
drm-intel-nightly, and it compiles fine.

However, the following issues exist:

*) If you boot with the kernel parameter vga=792 (i.e. the same console
resolutions as initiated by KMS) the system just hangs with a black
screen. Booting aborts, nothing happens.

*) Watermark settings are *still* not correct. *SIGH*, *sigh*

intel_reg_read 0x20d8
0x20D8 : 0x11F0104

This is a watermark level of 4. As I said multiple times, the watermark
register needs to be *AT LEAST* eight (in numbers, 8) to have a stable
display. It is stable between 8 and 32.

To reproduce, use a panning display with xrandr:

xrandr --output DVI1 --mode 1024x768 --panning 2048x1536

then scroll, and see the display flicker.

Folks, I really appreciate all your effort, but I would be really happy
if my comments on the wrong watermarks wouldn't be continuously ignored.
I submitted patches, twice, thrice... all went into the trash.

Greetings,
Thomas