DDC: no ddc bus - possible BIOS bug

[Alex Deucher]

2011/1/3 屋国遥 <hyagni at gmail.com>:
> 2011/1/4 Alex Deucher <alexdeucher at gmail.com>:
>> 2010/12/30 屋国遥 <hyagni at gmail.com>:
>>> 2010/12/31 Alex Deucher <alexdeucher at gmail.com>:
>>>> On Thu, Dec 30, 2010 at 10:25 AM, 屋国遥 <hyagni at gmail.com> wrote:
>>>>> Hello, all.
>>>>>
>>>>> I am trying to make dual-head environment on Mac Pro with Ubuntu
>>>>> 10.10.  My Mac Pro has the Radeon HD 2600 XT graphic card, so I decided
>>>>> to use the radeon driver.
>>>>>
>>>>> Now, I connect two monitors (the same SAMSUNG monitors) and boot the
>>>>> system and X, one display works well, but the other is not recognized.
>>>>> In dmesg, I found out the following error message.
>>>>>
>>>>> I googled the message and found
>>>>> <http://www.mail-archive.com/xorg-driver-ati@lists.x.org/msg16768.html>
>>>>> and <https://bugs.freedesktop.org/show_bug.cgi?id=29255>.  Referring
>>>>> to these posts, I upgraded the kernel to 2.6.36
>>>>> (http://kernel.ubuntu.com/~kernel-ppa/mainline/v2.6.36-maverick/) and
>>>>> also graphic drivers (https://launchpad.net/~xorg-edgers/+archive/ppa).
>>>>>
>>>>> However, the same error is displayed.
>>>>>
>>>>> I am sorry to say that I have no idea how to use Alex's patch to
>>>>> `radeon_atombios.c' because of my poor knowledge of Linux.
>>>>> Is not this change included in the recent kernel or drivers?
>>>>>
>>>>>
>>>>> Because dual-head environment works successfully on Mac, I suspect the
>>>>> monitor or graphic card has no problem.
>>>>>
>>>>
>>>> You will need a custom patch for your system.  That patch referenced
>>>> in the above thread only applies to evergreen chips.  I suspect apple
>>>> forgot to specify the ddc assignment for one of the heads in their
>>>> vbios and their driver most likely use hardcoded values.  Please send
>>>> me a copy of the vbios from your system, and I'll send you a patch to
>>>> fix it.  Also please attach the pci device and subsystem ids for your
>>>> card (lspci -vnn).  Also, what connectors does your card actually
>>>> have?  Two DVI-I?  Two DVI-I and one TV-out?  It looks like some of
>>>> the encoder mapping might be wrong on your system too.  I can help get
>>>> that fixed up as well.
>>>>
>>>> To get the vbios:
>>>> (as root)
>>>> (use lspci to get the bus id)
>>>> cd /sys/bus/pci/devices/<pci bus id>
>>>> echo 1 > rom
>>>> cat rom > /tmp/vbios.rom
>>>> echo 0 > rom
>>>>
>>>> Alex
>>>
>>> Hi, Alex.
>>> Thank you for your fast reply.
>>>
>>
>> The attached patch should fix it.  I think Apple supports TV-out via a
>> DVI to TV dongle, so you should see a DIN connector with this patch,
>> but both DVI's should work correctly.
>>
>> Alex
>
> Hello, Alex
>
> Your patch worked perfectly.  Both DVI is found now.
>

Excellent!  I've sent the patch to Dave for inclusion upstream.

Alex

> Thank you.
>
>>
>>> I understood the situation.
>>>
>>> My card has just two DVI-I connectors, no TV-out.
>>> The attached file is vbios.rom.
>>> lspci -vnn result is the following (only the section of VGA controller).
>>>
>>> 02:00.0 VGA compatible controller [0300]: ATI Technologies Inc RV630
>>> [Radeon HD 2600XT] [1002:9588] (prog-if 00 [VGA controller])
>>>        Subsystem: Apple Computer Inc. Device [106b:00a6]
>>>        Physical Slot: 1
>>>        Flags: bus master, fast devsel, latency 0, IRQ 56
>>>        Memory at 80000000 (64-bit, prefetchable) [size=256M]
>>>        Memory at 90a20000 (64-bit, non-prefetchable) [size=64K]
>>>        I/O ports at 2000 [size=256]
>>>        Expansion ROM at 90a00000 [disabled] [size=128K]
>>>        Capabilities: <access denied>
>>>        Kernel driver in use: radeon
>>>        Kernel modules: radeon
>>>
>>>
>>> --
>>> Haruka YAGNI
>>> hyagni at gmail.com
>>>
>>
>
>
>
> --
> Haruka YAGNI
> hyagni at gmail.com
>