On Fri, Sep 19, 2014 at 6:07 PM, Jonathan Gray <j...@jsg.id.au> wrote:
> On Fri, Sep 19, 2014 at 02:22:49PM +0200, Tony Sarendal wrote: > > Good afternoon, > > > > Friday question: > > Does anyone have recommendation on graphics hardware to use for 4k > screens > > and OpenBSD ? > > > > I'm thinking about improving my workstation. I run lots of terminal > > windows, a web browser, > > and the default window manager. As I like eye candy I may even do > "xsetroot > > -solid black". > > > > What I want is a stable work environment where I can reboot my > workstation > > every > > 6 months or so. This with a 4k screen. Doable ? > > The short version is it won't work yet, the longer version > is you should carefully check what the graphics hardware, monitor > and software support. > > For Intel the HDMI 4k at 30 Hz modes are only supported on Haswell, > ie i[357]-4xxx. On the AMD side HDMI 4k at 30 Hz modes are only > supported on Southern Islands parts according to > http://xorg.freedesktop.org/wiki/RadeonFeature/ which are > Radeon HD >= 77xx. The Southern Islands parts are best avoided as > xf86-video-ati only supports 2D acceleration via Glamor-EGL which on > Southern Islands radeons requires a Mesa driver that has a hard > requirement on LLVM, working EGL drm platform, and other things. > And the kernel only knows about the initial round of Southern Islands > parts, not all of those that were later released including > the newer integrated graphics with Kaveri. It seems it should > be possible to use 4k modes with displayport on Northern Islands/HD6xxx > if the screen was presented as two smaller screens via MST as > Northern Islands radeons support displayport 1.2 and MST. > This isn't an option for older Intel parts as ivybridge for > example only supports displayport 1.1 with no MST. > > The HDMI 1.4 4k modes make use of a CEA vendor extension > in the blob of data from the display that describes the > modes (EDID). Support for that was added in drm 3.12. > > Many of the 4k displays present themselves as multiple > displayport displays/streams, support for that was added > in drm 3.17. > > OpenBSD has roughly drm 3.8.13.28 at the moment. > > hdmi 1.4, drm 3.12 > 3840x2160@30Hz > 3840x2160@25Hz > 3840x2160@24Hz > > hdmi 2.0 > 4k @ 60Hz, drm ? > > displayport 1.2 4k 30Hz single stream transport (SST), drm 3.12? > > displayport 1.2 4k 60Hz multi stream transport (MST), drm 3.17 > > displayport 1.? 4k 60Hz single stream transport (4K60 SST), drm ? > > displayport 1.? dell 5k 5120x2880@?, MST? drm ? > Thanks for taking the time, Jonathan. Regards Tony
