gma500_gfx black screen

gma500_gfx black screen

[Markus H]

Hi,

I am getting a black screen as soon as I am loading the gma500_gfx
driver on a Dell Latitude ST tablet (powered by an Atom Z570, GPU
being a GMA600 with PCIID 8086:40102).
This happens with kernel 3.5.3 (Ubunutu 12.10 beta 1 and with
self-built kernels from gentoo-souces) as well as several other
kernels version past 3.0.
I could not find any indication that this problem has been fixed yet in 3.6rc.

I am currently stuck at trying to debug the issue: I can't read any
output (e.g. from a kernel panic) after typing modprobe gma500_gfx.

I could not setup a serial console that would be useful:
I have to use a USB to serial converter as the tablet has no serial port.
I can't get a serial console at all with the Ubuntu stock kernel
probably because the pl2303 driver is not built into the kernel but
rather loaded as module.
When booting a gentoo system with a kernel that has pl2303 built in I
only get boot messages up to xx kb unused memory has been freed and
nothing after that so I miss the kernel panic (if one happens).
When booting that same system with gma500_gfx built-in I don't get any
output on serial at all, probably because the system hangs before it
has initialized the usb console.


So I have two questions:
1. What other debugging options do I have so I can help with fixing
the gma500_gfx driver.
2. Are there any single commits I could try on top of e.g. a stock
3.2.x kernel to see which one caused this regression?

Greetings,
Markus

Re: gma500_gfx black screen

[Alan Cox]

> I could not find any indication that this problem has been fixed yet
> in 3.6rc.

Should be fixed in the very latest 3.6-rc. I got a report from someone
else that I could duplicate and pin down exactly. It's made somewhat
more complicated by the fact that another bug got introduced and then
fixed across the same period.

> I have to use a USB to serial converter as the tablet has no serial
> port. I can't get a serial console at all with the Ubuntu stock kernel
> probably because the pl2303 driver is not built into the kernel but
> rather loaded as module.

Correct

> 1. What other debugging options do I have so I can help with fixing
> the gma500_gfx driver.
> 2. Are there any single commits I could try on top of e.g. a stock
> 3.2.x kernel to see which one caused this regression?

Can you try the latest 3.6-rc release. The commit in question is
"gma500: Fix regression on Oaktrail devices"

Re: gma500_gfx black screen

[Markus H]

Hi,

> Should be fixed in the very latest 3.6-rc. I got a report from someone
> else that I could duplicate and pin down exactly. It's made somewhat
> more complicated by the fact that another bug got introduced and then
> fixed across the same period.

Oh I thought that one was irrelevant because I mixed up all the GMA600
codenames.

> Can you try the latest 3.6-rc release. The commit in question is
> "gma500: Fix regression on Oaktrail devices"

I will try 3.6-rc6 and report back.


Thanks,
Markus

Re: gma500_gfx black screen

[Markus H]

Hi,

>> Should be fixed in the very latest 3.6-rc. I got a report from soeone
>> else that I could duplicate and pin down exactly. It's made somewhat
>> more complicated by the fact that another bug got introduced and then
>> fixed across the same period.

>> Can you try the latest 3.6-rc release. The commit in question is
>> "gma500: Fix regression on Oaktrail devices"
>
> I will try 3.6-rc6 and report back.

Works fine (at least with fb console, setting up xorg at the moment).

Thanks,
Markus

Re: gma500_gfx black screen

[Dimitar]

Markus H <hauschild.markus <at> gmail.com> writes:

> 
> Hi,
> 
> >> Should be fixed in the very latest 3.6-rc. I got a report from soeone
> >> else that I could duplicate and pin down exactly. It's made somewhat
> >> more complicated by the fact that another bug got introduced and then
> >> fixed across the same period.
> 
> >> Can you try the latest 3.6-rc release. The commit in question is
> >> "gma500: Fix regression on Oaktrail devices"
> >
> > I will try 3.6-rc6 and report back.
> 
> Works fine (at least with fb console, setting up xorg at the moment).
> 
> Thanks,
> Markus
> 


I tried kernel 3.6.3 and still doesn't work :S
Any suggestions?

Thank you very much.
Regards, 
Dimitar