drm/i915: Refactor common ringbuffer allocation code

A small, very small, step to sharing the duplicate code between
execlists and legacy submission engines, starting with the ringbuffer
allocation code.

Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Arun Siluvery <arun.siluvery@linux.intel.com>
Cc: Mika Kuoppala <mika.kuoppala@intel.com>
Cc: Dave Gordon <david.s.gordon@intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Reviewed-by: Mika Kuoppala <mika.kuoppala@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

3 files changed, 70 insertions, 76 deletions

diff --git a/drivers/gpu/drm/i915/intel_lrc.c b/drivers/gpu/drm/i915/intel_lrc.c
index 40cbba4ea4ba..28a712e7d2d0 100644
--- a/drivers/gpu/drm/i915/intel_lrc.c
+++ b/drivers/gpu/drm/i915/intel_lrc.c
@@ -2340,8 +2340,7 @@ void intel_lr_context_free(struct intel_context *ctx)
                                 i915_gem_object_ggtt_unpin(ctx_obj);
                         }
                         WARN_ON(ctx->engine[ring->id].pin_count);
-                        intel_destroy_ringbuffer_obj(ringbuf);
-                        kfree(ringbuf);
+                        intel_ringbuffer_free(ringbuf);
                         drm_gem_object_unreference(&ctx_obj->base);
                 }
         }
@@ -2442,42 +2441,20 @@ int intel_lr_context_deferred_create(struct intel_context *ctx,
                         I915_WRITE(GEN8_GTCR, GEN8_GTCR_INVALIDATE);
         }
 
-        ringbuf = kzalloc(sizeof(*ringbuf), GFP_KERNEL);
-        if (!ringbuf) {
-                DRM_DEBUG_DRIVER("Failed to allocate ringbuffer %s\n",
-                                ring->name);
-                ret = -ENOMEM;
+        ringbuf = intel_engine_create_ringbuffer(ring, 4 * PAGE_SIZE);
+        if (IS_ERR(ringbuf)) {
+                ret = PTR_ERR(ringbuf);
                 goto error_unpin_ctx;
         }
 
-        ringbuf->ring = ring;
-
-        ringbuf->size = 4 * PAGE_SIZE;
-        ringbuf->effective_size = ringbuf->size;
-        ringbuf->head = 0;
-        ringbuf->tail = 0;
-        ringbuf->last_retired_head = -1;
-        intel_ring_update_space(ringbuf);
-
-        if (ringbuf->obj == NULL) {
-                ret = intel_alloc_ringbuffer_obj(dev, ringbuf);
+        if (is_global_default_ctx) {
+                ret = intel_pin_and_map_ringbuffer_obj(dev, ringbuf);
                 if (ret) {
-                        DRM_DEBUG_DRIVER(
-                                "Failed to allocate ringbuffer obj %s: %d\n",
-                                ring->name, ret);
-                        goto error_free_rbuf;
+                        DRM_ERROR(
+                                  "Failed to pin and map ringbuffer %s: %d\n",
+                                  ring->name, ret);
+                        goto error_ringbuf;
                 }
-
-                if (is_global_default_ctx) {
-                        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);
-                                goto error_destroy_rbuf;
-                        }
-                }
-
         }
 
         ret = populate_lr_context(ctx, ctx_obj, ring, ringbuf);
@@ -2519,10 +2496,8 @@ int intel_lr_context_deferred_create(struct intel_context *ctx,
 error:
         if (is_global_default_ctx)
                 intel_unpin_ringbuffer_obj(ringbuf);
-error_destroy_rbuf:
-        intel_destroy_ringbuffer_obj(ringbuf);
-error_free_rbuf:
-        kfree(ringbuf);
+error_ringbuf:
+        intel_ringbuffer_free(ringbuf);
 error_unpin_ctx:
         if (is_global_default_ctx)
                 i915_gem_object_ggtt_unpin(ctx_obj);
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
index 6e6b8db996ef..20a75bb516ac 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.c
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
@@ -1996,14 +1996,14 @@ int intel_pin_and_map_ringbuffer_obj(struct drm_device *dev,
         return 0;
 }
 
-void intel_destroy_ringbuffer_obj(struct intel_ringbuffer *ringbuf)
+static void intel_destroy_ringbuffer_obj(struct intel_ringbuffer *ringbuf)
 {
         drm_gem_object_unreference(&ringbuf->obj->base);
         ringbuf->obj = NULL;
 }
 
-int intel_alloc_ringbuffer_obj(struct drm_device *dev,
-                               struct intel_ringbuffer *ringbuf)
+static int intel_alloc_ringbuffer_obj(struct drm_device *dev,
+                                      struct intel_ringbuffer *ringbuf)
 {
         struct drm_i915_gem_object *obj;
 
@@ -2023,6 +2023,48 @@ int intel_alloc_ringbuffer_obj(struct drm_device *dev,
         return 0;
 }
 
+struct intel_ringbuffer *
+intel_engine_create_ringbuffer(struct intel_engine_cs *engine, int size)
+{
+        struct intel_ringbuffer *ring;
+        int ret;
+
+        ring = kzalloc(sizeof(*ring), GFP_KERNEL);
+        if (ring == NULL)
+                return ERR_PTR(-ENOMEM);
+
+        ring->ring = engine;
+
+        ring->size = size;
+        /* Workaround an erratum on the i830 which causes a hang if
+         * the TAIL pointer points to within the last 2 cachelines
+         * of the buffer.
+         */
+        ring->effective_size = size;
+        if (IS_I830(engine->dev) || IS_845G(engine->dev))
+                ring->effective_size -= 2 * CACHELINE_BYTES;
+
+        ring->last_retired_head = -1;
+        intel_ring_update_space(ring);
+
+        ret = intel_alloc_ringbuffer_obj(engine->dev, ring);
+        if (ret) {
+                DRM_ERROR("Failed to allocate ringbuffer %s: %d\n",
+                          engine->name, ret);
+                kfree(ring);
+                return ERR_PTR(ret);
+        }
+
+        return ring;
+}
+
+void
+intel_ringbuffer_free(struct intel_ringbuffer *ring)
+{
+        intel_destroy_ringbuffer_obj(ring);
+        kfree(ring);
+}
+
 static int intel_init_ring_buffer(struct drm_device *dev,
                                   struct intel_engine_cs *ring)
 {
@@ -2031,22 +2073,20 @@ static int intel_init_ring_buffer(struct drm_device *dev,
 
         WARN_ON(ring->buffer);
 
-        ringbuf = kzalloc(sizeof(*ringbuf), GFP_KERNEL);
-        if (!ringbuf)
-                return -ENOMEM;
-        ring->buffer = ringbuf;
-
         ring->dev = dev;
         INIT_LIST_HEAD(&ring->active_list);
         INIT_LIST_HEAD(&ring->request_list);
         INIT_LIST_HEAD(&ring->execlist_queue);
         i915_gem_batch_pool_init(dev, &ring->batch_pool);
-        ringbuf->size = 32 * PAGE_SIZE;
-        ringbuf->ring = ring;
         memset(ring->semaphore.sync_seqno, 0, sizeof(ring->semaphore.sync_seqno));
 
         init_waitqueue_head(&ring->irq_queue);
 
+        ringbuf = intel_engine_create_ringbuffer(ring, 32 * PAGE_SIZE);
+        if (IS_ERR(ringbuf))
+                return PTR_ERR(ringbuf);
+        ring->buffer = ringbuf;
+
         if (I915_NEED_GFX_HWS(dev)) {
                 ret = init_status_page(ring);
                 if (ret)
@@ -2058,15 +2098,6 @@ static int intel_init_ring_buffer(struct drm_device *dev,
                         goto error;
         }
 
-        WARN_ON(ringbuf->obj);
-
-        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",
@@ -2075,14 +2106,6 @@ static int intel_init_ring_buffer(struct drm_device *dev,
                 goto error;
         }
 
-        /* Workaround an erratum on the i830 which causes a hang if
-         * the TAIL pointer points to within the last 2 cachelines
-         * of the buffer.
-         */
-        ringbuf->effective_size = ringbuf->size;
-        if (IS_I830(dev) || IS_845G(dev))
-                ringbuf->effective_size -= 2 * CACHELINE_BYTES;
-
         ret = i915_cmd_parser_init_ring(ring);
         if (ret)
                 goto error;
@@ -2090,7 +2113,7 @@ static int intel_init_ring_buffer(struct drm_device *dev,
         return 0;
 
 error:
-        kfree(ringbuf);
+        intel_ringbuffer_free(ringbuf);
         ring->buffer = NULL;
         return ret;
 }
@@ -2098,19 +2121,18 @@ error:
 void intel_cleanup_ring_buffer(struct intel_engine_cs *ring)
 {
         struct drm_i915_private *dev_priv;
-        struct intel_ringbuffer *ringbuf;
 
         if (!intel_ring_initialized(ring))
                 return;
 
         dev_priv = to_i915(ring->dev);
-        ringbuf = ring->buffer;
 
         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);
+        intel_unpin_ringbuffer_obj(ring->buffer);
+        intel_ringbuffer_free(ring->buffer);
+        ring->buffer = NULL;
 
         if (ring->cleanup)
                 ring->cleanup(ring);
@@ -2119,9 +2141,6 @@ void intel_cleanup_ring_buffer(struct intel_engine_cs *ring)
 
         i915_cmd_parser_fini_ring(ring);
         i915_gem_batch_pool_fini(&ring->batch_pool);
-
-        kfree(ringbuf);
-        ring->buffer = NULL;
 }
 
 static int ring_wait_for_space(struct intel_engine_cs *ring, int n)
diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.h b/drivers/gpu/drm/i915/intel_ringbuffer.h
index 95b0b4b55fa6..49fa41dc0eb6 100644
--- a/drivers/gpu/drm/i915/intel_ringbuffer.h
+++ b/drivers/gpu/drm/i915/intel_ringbuffer.h
@@ -420,12 +420,12 @@ intel_write_status_page(struct intel_engine_cs *ring,
 #define I915_GEM_HWS_SCRATCH_INDEX      0x40
 #define I915_GEM_HWS_SCRATCH_ADDR (I915_GEM_HWS_SCRATCH_INDEX << MI_STORE_DWORD_INDEX_SHIFT)
 
-void intel_unpin_ringbuffer_obj(struct intel_ringbuffer *ringbuf);
+struct intel_ringbuffer *
+intel_engine_create_ringbuffer(struct intel_engine_cs *engine, int size);
 int intel_pin_and_map_ringbuffer_obj(struct drm_device *dev,
                                      struct intel_ringbuffer *ringbuf);
-void intel_destroy_ringbuffer_obj(struct intel_ringbuffer *ringbuf);
-int intel_alloc_ringbuffer_obj(struct drm_device *dev,
-                               struct intel_ringbuffer *ringbuf);
+void intel_unpin_ringbuffer_obj(struct intel_ringbuffer *ringbuf);
+void intel_ringbuffer_free(struct intel_ringbuffer *ring);
 
 void intel_stop_ring_buffer(struct intel_engine_cs *ring);
 void intel_cleanup_ring_buffer(struct intel_engine_cs *ring);