drm/i915: Remove unnecessary ggtt_offset_bias from i915_gem_context

Since ggtt_offset_bias is now stored in ggtt.pin_bias, it is duplicated
inside i915_gem_context, and can instead be accessed directly from ggtt.

v3:
Added a helper function to retrieve the ggtt.pin_bias from the vma.

v4:
Moved the helper function to the previous patch in the series.
Dropped the bias from intel_ring_pin. This introduces a slight functional
change since we are always pinning the ring a bit higher if GuC is present
even though we don't really need to.

v8:
Fixed patch not applying on the most recent upstream.

Signed-off-by: Jakub Bartmiński <jakub.bartminski@intel.com>
Cc: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Michał Winiarski <michal.winiarski@intel.com>
Cc: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20180727141148.30874-4-jakub.bartminski@intel.com

1 files changed, 6 insertions, 10 deletions

diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 27b24000412f..b293e1dedb8e 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -1003,11 +1003,7 @@ i915_emit_bb_start(struct i915_request *rq,
         return 0;
 }
 
-
-
-int intel_ring_pin(struct intel_ring *ring,
-                   struct drm_i915_private *i915,
-                   unsigned int offset_bias)
+int intel_ring_pin(struct intel_ring *ring, struct drm_i915_private *i915)
 {
         enum i915_map_type map = HAS_LLC(i915) ? I915_MAP_WB : I915_MAP_WC;
         struct i915_vma *vma = ring->vma;
@@ -1017,10 +1013,11 @@ int intel_ring_pin(struct intel_ring *ring,
 
         GEM_BUG_ON(ring->vaddr);
 
-
         flags = PIN_GLOBAL;
-        if (offset_bias)
-                flags |= PIN_OFFSET_BIAS | offset_bias;
+
+        /* Ring wraparound at offset 0 sometimes hangs. No idea why. */
+        flags |= PIN_OFFSET_BIAS | i915_ggtt_pin_bias(vma);
+
         if (vma->obj->stolen)
                 flags |= PIN_MAPPABLE;
         else
@@ -1408,8 +1405,7 @@ static int intel_init_ring_buffer(struct intel_engine_cs *engine)
                 goto err;
         }
 
-        /* Ring wraparound at offset 0 sometimes hangs. No idea why. */
-        err = intel_ring_pin(ring, engine->i915, I915_GTT_PAGE_SIZE);
+        err = intel_ring_pin(ring, engine->i915);
         if (err)
                 goto err_ring;