Subject: Re: The radeon framebuffer device panics init (on i386)
To: Michael Lorenz <firstname.lastname@example.org>
From: Vincent <email@example.com>
Date: 12/23/2006 22:13:04
According to Michael Lorenz:
>>> Hmm, so you r display does provide EDID data after all. I didn't see
>>> any EDID stuff in your dmesg output but since the default mode used
>>> by radeonfb is the same as what your display reports that doesn't
>>> matter for now.
>> It is supposed to do so?
> Yes. And at least on my iBook it works just fine. To my surprise I might
Well, there is obviously something more seriously wrong.
>> I think Xorg scans all the PCI bus, detects overlaps, and decides to
>> map the video BIOS in a hole.
> Maybe - when X is up you can have a look with pcictl if there's
> something else than 0x00000000 in the ROM BAR - somehow I doubt it. In
> fact I think there's no dedicated video BIOS ROM and video BIOS is part
> of the main BIOS.
No, there is nothing else, because I precisely dumped the BIOS under X.
"Expansion ROM Base Address: 0x00000000"
Anyhow, a ROM BAR should be ROM itself, no?
> What you could do is:
> - - find a safe address range for the ROM BAR ( usually you'll need 64kB
> or 128kB )
> - - use pcitweak to set the address and enable the ROM
> - - write a little program that mmap()s the ROM via /dev/mem ( just open
> /dev/mem for reading, use the address you picked as offset for mmap() )
> and see what's there. If you get SIGBUS, SIGSEGV or bogus data ( like
> all 0x00000000 or 0xffffffff ) then there's likely no ROM.
Somehow, X seems to find something when launch, so I guess there is a
piece of ROM somewhere. I'll try to tinker the way you indicated.
> Hmm, maybe it makes sense to have radeonfb look at the 'traditional'
> physical address of the video BIOS and cross fingers.
>> I've not tested CRT output yet, will do that now.
> That would at least tell us if radeonfb doesn't feed the panel the right
> way or if there's something more fundamental wrong.
The CRT output does not work either. At least my TV screen stays blank.
I'll keep you posted.