drm/i915: Add explicit request management to i915_gem_init_hw()

Now that a single per ring loop is being done for all the different
intialisation steps in i915_gem_init_hw(), it is possible to add proper request
management as well. The last remaining issue is that the context enable call
eventually ends up within *_render_state_init() and this does its own private
_i915_add_request() call.

This patch adds explicit request creation and submission to the top level loop
and removes the add_request() from deep within the sub-functions.

v2: Updated for removal of batch_obj from add_request call in previous patch.

For: VIZ-5115
Signed-off-by: John Harrison <John.C.Harrison@Intel.com>
Reviewed-by: Tomas Elf <tomas.elf@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_drv.h

@@ -2169,7 +2169,8 @@ struct drm_i915_gem_request {
 	struct intel_context *ctx;
 	struct intel_ringbuffer *ringbuf;
 
-	/** Batch buffer related to this request if any */
+	/** Batch buffer related to this request if any (used for
+	    error state dump only) */
 	struct drm_i915_gem_object *batch_obj;
 
 	/** Time at which this request was emitted, in jiffies. */

drivers/gpu/drm/i915/i915_gem.c

@@ -5069,8 +5069,16 @@ i915_gem_init_hw(struct drm_device *dev)
 
 	/* Now it is safe to go back round and do everything else: */
 	for_each_ring(ring, dev_priv, i) {
+		struct drm_i915_gem_request *req;
+
 		WARN_ON(!ring->default_context);
 
+		ret = i915_gem_request_alloc(ring, ring->default_context, &req);
+		if (ret) {
+			i915_gem_cleanup_ringbuffer(dev);
+			goto out;
+		}
+
 		if (ring->id == RCS) {
 			for (j = 0; j < NUM_L3_SLICES(dev); j++)
 				i915_gem_l3_remap(ring, j);
@@ -5079,6 +5087,7 @@ i915_gem_init_hw(struct drm_device *dev)
 		ret = i915_ppgtt_init_ring(ring);
 		if (ret && ret != -EIO) {
 			DRM_ERROR("PPGTT enable ring #%d failed %d\n", i, ret);
+			i915_gem_request_cancel(req);
 			i915_gem_cleanup_ringbuffer(dev);
 			goto out;
 		}
@@ -5086,9 +5095,12 @@ i915_gem_init_hw(struct drm_device *dev)
 		ret = i915_gem_context_enable(ring);
 		if (ret && ret != -EIO) {
 			DRM_ERROR("Context enable ring #%d failed %d\n", i, ret);
+			i915_gem_request_cancel(req);
 			i915_gem_cleanup_ringbuffer(dev);
 			goto out;
 		}
+
+		i915_add_request_no_flush(ring);
 	}
 
 out:

drivers/gpu/drm/i915/i915_gem_render_state.c

@@ -173,8 +173,6 @@ int i915_gem_render_state_init(struct intel_engine_cs *ring)
 
 	i915_vma_move_to_active(i915_gem_obj_to_ggtt(so.obj), ring);
 
-	__i915_add_request(ring, NULL, NULL, true);
-	/* __i915_add_request moves object to inactive if it fails */
 out:
 	i915_gem_render_state_fini(&so);
 	return ret;

drivers/gpu/drm/i915/intel_lrc.c

@@ -1579,8 +1579,6 @@ static int intel_lr_context_render_state_init(struct intel_engine_cs *ring,
 {
 	struct intel_ringbuffer *ringbuf = ctx->engine[ring->id].ringbuf;
 	struct render_state so;
-	struct drm_i915_file_private *file_priv = ctx->file_priv;
-	struct drm_file *file = file_priv ? file_priv->file : NULL;
 	int ret;
 
 	ret = i915_gem_render_state_prepare(ring, &so);
@@ -1599,9 +1597,6 @@ static int intel_lr_context_render_state_init(struct intel_engine_cs *ring,
 
 	i915_vma_move_to_active(i915_gem_obj_to_ggtt(so.obj), ring);
 
-	__i915_add_request(ring, file, NULL, true);
-	/* intel_logical_ring_add_request moves object to inactive if it
-	 * fails */
 out:
 	i915_gem_render_state_fini(&so);
 	return ret;