drm/i915/bdw: Pin the ringbuffer backing object to GGTT on-demand

[deliverable/linux.git] / drivers / gpu / drm / i915 / intel_ringbuffer.c

diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index ae092589ea0ce61daabe4c262fc46ef30e551f49..0a4f35e735c3ed9e2c352716bb83862468b83db4 100644 (file)
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -1722,13 +1722,42 @@ static int init_phys_status_page(struct intel_engine_cs *ring)
        return 0;
 }
 
-void intel_destroy_ringbuffer_obj(struct intel_ringbuffer *ringbuf)
+void intel_unpin_ringbuffer_obj(struct intel_ringbuffer *ringbuf)
 {
-       if (!ringbuf->obj)
-               return;
-
        iounmap(ringbuf->virtual_start);
+       ringbuf->virtual_start = NULL;
        i915_gem_object_ggtt_unpin(ringbuf->obj);
+}
+
+int intel_pin_and_map_ringbuffer_obj(struct drm_device *dev,
+                                    struct intel_ringbuffer *ringbuf)
+{
+       struct drm_i915_private *dev_priv = to_i915(dev);
+       struct drm_i915_gem_object *obj = ringbuf->obj;
+       int ret;
+
+       ret = i915_gem_obj_ggtt_pin(obj, PAGE_SIZE, PIN_MAPPABLE);
+       if (ret)
+               return ret;
+
+       ret = i915_gem_object_set_to_gtt_domain(obj, true);
+       if (ret) {
+               i915_gem_object_ggtt_unpin(obj);
+               return ret;
+       }
+
+       ringbuf->virtual_start = ioremap_wc(dev_priv->gtt.mappable_base +
+                       i915_gem_obj_ggtt_offset(obj), ringbuf->size);
+       if (ringbuf->virtual_start == NULL) {
+               i915_gem_object_ggtt_unpin(obj);
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
+void intel_destroy_ringbuffer_obj(struct intel_ringbuffer *ringbuf)
+{
        drm_gem_object_unreference(&ringbuf->obj->base);
        ringbuf->obj = NULL;
 }
@@ -1736,12 +1765,7 @@ void intel_destroy_ringbuffer_obj(struct intel_ringbuffer *ringbuf)
 int intel_alloc_ringbuffer_obj(struct drm_device *dev,
                               struct intel_ringbuffer *ringbuf)
 {
-       struct drm_i915_private *dev_priv = to_i915(dev);
        struct drm_i915_gem_object *obj;
-       int ret;
-
-       if (ringbuf->obj)
-               return 0;
 
        obj = NULL;
        if (!HAS_LLC(dev))
@@ -1754,30 +1778,9 @@ int intel_alloc_ringbuffer_obj(struct drm_device *dev,
        /* mark ring buffers as read-only from GPU side by default */
        obj->gt_ro = 1;
 
-       ret = i915_gem_obj_ggtt_pin(obj, PAGE_SIZE, PIN_MAPPABLE);
-       if (ret)
-               goto err_unref;
-
-       ret = i915_gem_object_set_to_gtt_domain(obj, true);
-       if (ret)
-               goto err_unpin;
-
-       ringbuf->virtual_start =
-               ioremap_wc(dev_priv->gtt.mappable_base + i915_gem_obj_ggtt_offset(obj),
-                               ringbuf->size);
-       if (ringbuf->virtual_start == NULL) {
-               ret = -EINVAL;
-               goto err_unpin;
-       }
-
        ringbuf->obj = obj;
-       return 0;
 
-err_unpin:
-       i915_gem_object_ggtt_unpin(obj);
-err_unref:
-       drm_gem_object_unreference(&obj->base);
-       return ret;
+       return 0;
 }
 
 static int intel_init_ring_buffer(struct drm_device *dev,
@@ -1814,10 +1817,21 @@ static int intel_init_ring_buffer(struct drm_device *dev,
                        goto error;
        }
 
-       ret = intel_alloc_ringbuffer_obj(dev, ringbuf);
-       if (ret) {
-               DRM_ERROR("Failed to allocate ringbuffer %s: %d\n", ring->name, ret);
-               goto error;
+       if (ringbuf->obj == NULL) {
+               ret = intel_alloc_ringbuffer_obj(dev, ringbuf);
+               if (ret) {
+                       DRM_ERROR("Failed to allocate ringbuffer %s: %d\n",
+                                       ring->name, ret);
+                       goto error;
+               }
+
+               ret = intel_pin_and_map_ringbuffer_obj(dev, ringbuf);
+               if (ret) {
+                       DRM_ERROR("Failed to pin and map ringbuffer %s: %d\n",
+                                       ring->name, ret);
+                       intel_destroy_ringbuffer_obj(ringbuf);
+                       goto error;
+               }
        }
 
        /* Workaround an erratum on the i830 which causes a hang if
@@ -1858,6 +1872,7 @@ void intel_cleanup_ring_buffer(struct intel_engine_cs *ring)
        intel_stop_ring_buffer(ring);
        WARN_ON(!IS_GEN2(ring->dev) && (I915_READ_MODE(ring) & MODE_IDLE) == 0);
 
+       intel_unpin_ringbuffer_obj(ringbuf);
        intel_destroy_ringbuffer_obj(ringbuf);
        ring->preallocated_lazy_request = NULL;
        ring->outstanding_lazy_seqno = 0;