Posted Sep 12, 2013 8:37 UTC (Thu) by jnareb (subscriber, #46500)
Parent article: 3.12 merge window, part 2
>* The direct rendering graphics layer has gained the concept of "render nodes," which separate the rendering of graphics from modesetting and other display control; the "big three" graphics drivers all support this concept. See this post from David Herrmann for more information on where this work is going.
In linked post there is said that render-nodes are not bound to a specific card and that driver-unspecific user-space (which can be relatively unprivileged) should not and can not ask "how do I find the render-node for a given card?”.
But I wonder, as there are hardware where there are graphics cards with different capabilities (e.g. Tesla for GPGPU, GeForce for display), would you be able to ask for said capabilities to select render node?
Posted Sep 12, 2013 14:13 UTC (Thu) by lambda (subscriber, #40735)
[Link]
I think that this comment from the blog post answers that question:
With custom heuristics. There is currently no notion of “speed” in the DRM API, but afair Ian was implementing an OpenGL extension to give some useful information to the user. So you could just open all render-nodes, see what they provide and then use them.
Basically, the answer is that you open up each render node, query it for its capabilities, and then use the appropriate one for your task.
