drm/i915/bdw: Generic logical ring init and cleanup

Allocate and populate the default LRC for every ring, call
gen-specific init/cleanup, init/fini the command parser and
set the status page (now inside the LRC object). These are
things all engines/rings have in common.

Stopping the ring before cleanup and initializing the seqnos
is left as a TODO task (we need more infrastructure in place
before we can achieve this).

v2: Check the ringbuffer backing obj for ring_is_initialized,
instead of the context backing obj (similar, but not exactly
the same).

Signed-off-by: Oscar Mateo <oscar.mateo@intel.com>
Reviewed-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_gem_context.c

@@ -445,10 +445,6 @@ int i915_gem_context_init(struct drm_device *dev)
 
 		/* NB: RCS will hold a ref for all rings */
 		ring->default_context = ctx;
-
-		/* FIXME: we really only want to do this for initialized rings */
-		if (i915.enable_execlists)
-			intel_lr_context_deferred_create(ctx, ring);
 	}
 
 	DRM_DEBUG_DRIVER("%s context support initialized\n",

drivers/gpu/drm/i915/intel_lrc.c

@@ -110,12 +110,60 @@ void intel_logical_ring_stop(struct intel_engine_cs *ring)
 
 void intel_logical_ring_cleanup(struct intel_engine_cs *ring)
 {
-	/* TODO */
+	if (!intel_ring_initialized(ring))
+		return;
+
+	/* TODO: make sure the ring is stopped */
+	ring->preallocated_lazy_request = NULL;
+	ring->outstanding_lazy_seqno = 0;
+
+	if (ring->cleanup)
+		ring->cleanup(ring);
+
+	i915_cmd_parser_fini_ring(ring);
+
+	if (ring->status_page.obj) {
+		kunmap(sg_page(ring->status_page.obj->pages->sgl));
+		ring->status_page.obj = NULL;
+	}
 }
 
 static int logical_ring_init(struct drm_device *dev, struct intel_engine_cs *ring)
 {
-	/* TODO */
+	int ret;
+	struct intel_context *dctx = ring->default_context;
+	struct drm_i915_gem_object *dctx_obj;
+
+	/* Intentionally left blank. */
+	ring->buffer = NULL;
+
+	ring->dev = dev;
+	INIT_LIST_HEAD(&ring->active_list);
+	INIT_LIST_HEAD(&ring->request_list);
+	init_waitqueue_head(&ring->irq_queue);
+
+	ret = intel_lr_context_deferred_create(dctx, ring);
+	if (ret)
+		return ret;
+
+	/* The status page is offset 0 from the context object in LRCs. */
+	dctx_obj = dctx->engine[ring->id].state;
+	ring->status_page.gfx_addr = i915_gem_obj_ggtt_offset(dctx_obj);
+	ring->status_page.page_addr = kmap(sg_page(dctx_obj->pages->sgl));
+	if (ring->status_page.page_addr == NULL)
+		return -ENOMEM;
+	ring->status_page.obj = dctx_obj;
+
+	ret = i915_cmd_parser_init_ring(ring);
+	if (ret)
+		return ret;
+
+	if (ring->init) {
+		ret = ring->init(ring);
+		if (ret)
+			return ret;
+	}
+
 	return 0;
 }
 
@@ -399,6 +447,8 @@ int intel_lr_context_deferred_create(struct intel_context *ctx,
 	int ret;
 
 	WARN_ON(ctx->legacy_hw_ctx.rcs_state != NULL);
+	if (ctx->engine[ring->id].state)
+		return 0;
 
 	context_size = round_up(get_lr_context_size(ring), 4096);
 

drivers/gpu/drm/i915/intel_ringbuffer.c

@@ -40,6 +40,23 @@
  */
 #define CACHELINE_BYTES 64
 
+bool
+intel_ring_initialized(struct intel_engine_cs *ring)
+{
+	struct drm_device *dev = ring->dev;
+
+	if (!dev)
+		return false;
+
+	if (i915.enable_execlists) {
+		struct intel_context *dctx = ring->default_context;
+		struct intel_ringbuffer *ringbuf = dctx->engine[ring->id].ringbuf;
+
+		return ringbuf->obj;
+	} else
+		return ring->buffer && ring->buffer->obj;
+}
+
 static inline int __ring_space(int head, int tail, int size)
 {
 	int space = head - (tail + I915_RING_FREE_SPACE);

drivers/gpu/drm/i915/intel_ringbuffer.h

@@ -289,11 +289,7 @@ struct  intel_engine_cs {
 	u32 (*get_cmd_length_mask)(u32 cmd_header);
 };
 
-static inline bool
+bool intel_ring_initialized(struct intel_engine_cs *ring);
-intel_ring_initialized(struct intel_engine_cs *ring)
-{
-	return ring->buffer && ring->buffer->obj;
-}
 
 static inline unsigned
 intel_ring_flag(struct intel_engine_cs *ring)