[Intel-gfx] [PATCH] drm/i915/execlists: WaDisableCtxRestoreArbitration is only needed in gen8

[Michel Thierry]

On 10/5/2017 11:28 AM, Chris Wilson wrote:
> Quoting Michel Thierry (2017-10-05 19:19:27)
>> WaDisableCtxRestoreArbitration was only applied for bdw and chv, but
>> this changed after the code got moved to gen8_emit_bb_start (and, at
>> least in my tree, there is no gen9_emit_bb_start).
> 
> But I need to make sure we enable arbitration at some point. :)
> It may not need the w/a name, but I was making very sure we didn't start
> a BB without ARB, or context-switch into the middle of a batch without
> ARB. That was my thinking, that there was no harm in overkill if we set
> it more often than strictly necessary.

Ok, thanks for the detailed explanation and yes, probably no harm in 
setting MI_ARB_ON.