patches.baytrail/0655-drm-i915-Allow-the-GPU-to-cache-stolen-memory.patch

From bb6729beb868d5d75aac9998fc3fa8e4f32aa337 Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Thu, 8 Aug 2013 14:41:06 +0100
Subject: drm/i915: Allow the GPU to cache stolen memory
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As a corollary to reviewing the interaction between LLC and our cache
domains, the GPU PTE bits are independent of the CPU PAT bits. As such
we can set the cache level on stolen memory based on how we wish the GPU
to cache accesses to it. So we are free to set the same default cache
levels as for normal bo, i.e. enable LLC cacheing by default where
appropriate.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
(cherry picked from commit d46f1c3f1372e3a72fab97c60480aa4a1084387f)
Signed-off-by: Darren Hart <dvhart@linux.intel.com>
---
 drivers/gpu/drm/i915/i915_gem_stolen.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_gem_stolen.c b/drivers/gpu/drm/i915/i915_gem_stolen.c
index 8912f489f53a..8b03327f74b9 100644
--- a/drivers/gpu/drm/i915/i915_gem_stolen.c
+++ b/drivers/gpu/drm/i915/i915_gem_stolen.c
@@ -296,9 +296,8 @@ _i915_gem_object_create_stolen(struct drm_device *dev,
 	i915_gem_object_pin_pages(obj);
 	obj->stolen = stolen;
 
-	obj->base.write_domain = I915_GEM_DOMAIN_GTT;
-	obj->base.read_domains = I915_GEM_DOMAIN_GTT;
-	obj->cache_level = I915_CACHE_NONE;
+	obj->base.read_domains = I915_GEM_DOMAIN_CPU | I915_GEM_DOMAIN_GTT;
+	obj->cache_level = HAS_LLC(dev) ? I915_CACHE_LLC : I915_CACHE_NONE;
 
 	return obj;
 
-- 
1.8.5.rc3