[Intel-gfx] [PATCH 51/53] drm/i915/bdw: Document Logical Rings, LR contexts and Execlists

[Daniel Vetter]

On Tue, Jun 17, 2014 at 11:46 AM, Mateo Lozano, Oscar
<oscar.mateo at intel.com> wrote:
> The comment appears in the commit message for " drm/i915/bdw: Implement context switching (somewhat) ":
>
>     v3: Use LRCA[31:12] as hwCtxId[19:0]. This guarantees that the HW context
>     ID we submit to the ELSP is globally unique and != 0 (Bspec requirements
>     of the software use-only bits of the Context ID in the Context Descriptor
>     Format) without the hassle of the previous submission Id construction.

I've meant a comment as to why reusing ctx->id isn't a good idea since
it's per-file an so not globally unique. Occasionally repeating and
stating the seemingly obvious won't hurt ;-)
-Daniel
-- 
Daniel Vetter
Software Engineer, Intel Corporation
+41 (0) 79 365 57 48 - http://blog.ffwll.ch