DRI3 and Present

Posted Oct 10, 2013 14:19 UTC (Thu) by chris.wilson (guest, #42619)
In reply to: DRI3 and Present by nix
Parent article: DRI3 and Present

DRI is the interface between the driver dependent portion of X, Mesa and a few other very select group of libraries (like vdpau, vaapi). Which DRI interface is supported is entirely dependent upon the DDX and cannot be chosen by the application, so it is sufficient to check /var/log/Xorg.0.log to see which is active on your system. The seemingly useful xdriinfo does not tell you which version of DRI is in use.

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DRI3 and Present

Posted Oct 10, 2013 14:50 UTC (Thu) by drag (guest, #31333) [Link] (1 responses)

Well, I am guessing, but I doubt that any X stuff is using DRI 1. X had it's own hardware drivers and fiddled with the bits on the hardware directly to get acceleration and do modesetting.

The DRI is used by OpenGL applications only at that era. So unless you are trying to get OpenGL acceleration on some ancient piece of hardware you should be fine.

DRI3 and Present

Posted Oct 11, 2013 7:01 UTC (Fri) by Jonno (guest, #49613) [Link]

> I can't help noticing from the slides of Ajax's talk that this might end up killing off DRI1. The question for me is... can I tell if anything I use is still using DRI1?

> So unless you are trying to get OpenGL acceleration on some ancient piece of hardware you should be fine.

Note that Mesa already dropped DRI1 support in 8.0, released Feb 2012.

Thus if your ancient hardware already needs a pre-8.0 (Feb 2012) Mesa you will now also need a pre-1.15 (~ Dec 2013) XServer.

Affected mesa drivers are i810, mach64, mga, r128, savage, sis, tdfx, and unichrome, all last released in Mesa 7.11.2 (Feb 2011).

The classic i915, i965, nouveau, radeon, r200, r300, and r600 drivers could also use DRI1 in pre-8.0 releases, but since Mesa 7.3 (Jan 2009) that was only necessary when using an old non-DRI2 capable XServer (pre-1.6; Feb 2009) or kernel (pre-2.6.29; Mar 2009).

So to summarize, this just means no XServer ≥1.15 or Mesa ≥8.0 on ancient hardware or Kernel <2.6.29; no Mesa ≥8.0 on XServer <1.6; and no XServer ≥1.16 with Mesa <7.3.

Oh, and if you mismatch these versions, all that happens is that you loose hardware acceleration. All applications will still work, just very slowly.

DRI3 and Present

Posted Oct 12, 2013 15:07 UTC (Sat) by nix (subscriber, #2304) [Link]

Ah, right. Judging by later responses, my Mesa 9.2 / Radeon 6875 system is entirely devoid of DRI1 support *already*, and nothing seems to have broken. (I thought it was almost entirely a Mesa-layer thing, so dropping DRI1 was probably unproblematic from a backward-compatibility POV, but wasn't sure.)