Quoting Matthew Auld (2020-11-27 12:07:06)
> From: CQ Tang
>
> When cache_level is NONE, we check HAS_LLC(i915).
> But additionally for DGFX, we also need to check
> HAS_SNOOP(i915) on system memory object to use
> I915_BO_CACHE_COHERENT_FOR_READ. on dg1, has_llc=0, and
> has_snoop=1. Otherwise,
From: CQ Tang
When cache_level is NONE, we check HAS_LLC(i915).
But additionally for DGFX, we also need to check
HAS_SNOOP(i915) on system memory object to use
I915_BO_CACHE_COHERENT_FOR_READ. on dg1, has_llc=0, and
has_snoop=1. Otherwise, we set obj->cache_choerent=0 and
have performance impact.
