5K iMac retina multi stream display port

[Andreas Tunek]

2015-10-04 6:31 GMT+02:00 Dave Airlie <airlied at gmail.com>:
> On 3 October 2015 at 04:03, Andreas Tunek <andreas.tunek at gmail.com> wrote:
>> Hi
>>
>> I sort of recall that somebody (Dave Airlied) work on this in order to
>> get the full 5K from a retina iMac. Was that work finished or is that
>> coming in 4.3 or later? Or was it abandoned? Or maybe I am not
>> remembering correctly?
>
> you can try a 4.2 kernel with radeon.mst=1
>
> I've no idea if it will work.

Didn't seem to have any effect. Is this a correct boot env:
[
root at iMacLinux tuna]# cat /proc/cmdline
BOOT_IMAGE=/vmlinuz-4.2.1-300.fc23.x86_64
root=UUID=e3e65337-b654-495f-b7c1-0212e1fd0797 ro rhgb quiet
LANG=en_US.UTF-8 radeon.mst=1

>
> Dave.