From: CQ Tang <cq.t...@intel.com>

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.

Cc: Chris P Wilson <chris.p.wil...@intel.com>
Cc: Ramalingam C <ramalinga...@intel.com>
Cc: Sudeep Dutt <sudeep.d...@intel.com>
Cc: Matthew Auld <matthew.a...@intel.com>
Signed-off-by: CQ Tang <cq.t...@intel.com>
---
 drivers/gpu/drm/i915/gem/i915_gem_object.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_object.c 
b/drivers/gpu/drm/i915/gem/i915_gem_object.c
index ddb448f275eb..be603171c444 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_object.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_object.c
@@ -95,6 +95,20 @@ void i915_gem_object_init(struct drm_i915_gem_object *obj,
        mutex_init(&obj->mm.get_dma_page.lock);
 }
 
+static bool i915_gem_object_use_llc(struct drm_i915_gem_object *obj)
+{
+       struct drm_i915_private *i915 = to_i915(obj->base.dev);
+
+       if (HAS_LLC(i915))
+               return true;
+
+       if (IS_DGFX(i915) && HAS_SNOOP(i915) &&
+           !i915_gem_object_is_lmem(obj))
+               return true;
+
+       return false;
+}
+
 /**
  * Mark up the object's coherency levels for a given cache_level
  * @obj: #drm_i915_gem_object
@@ -108,7 +122,7 @@ void i915_gem_object_set_cache_coherency(struct 
drm_i915_gem_object *obj,
        if (cache_level != I915_CACHE_NONE)
                obj->cache_coherent = (I915_BO_CACHE_COHERENT_FOR_READ |
                                       I915_BO_CACHE_COHERENT_FOR_WRITE);
-       else if (HAS_LLC(to_i915(obj->base.dev)))
+       else if (i915_gem_object_use_llc(obj))
                obj->cache_coherent = I915_BO_CACHE_COHERENT_FOR_READ;
        else
                obj->cache_coherent = 0;
-- 
2.26.2

_______________________________________________
Intel-gfx mailing list
Intel-gfx@lists.freedesktop.org
https://lists.freedesktop.org/mailman/listinfo/intel-gfx

Reply via email to