drm/i915: Fix startup failure in LRC mode after recent init changes

A previous commit introduced engine init changes:

    commit 372ee59699d9 ("drm/i915: Only init engines once")

This broke execlists as intel_lr_context_render_state_init was trying to emit
commands to the RCS for the default context before the ring->init_hw was called.

Made a new gen8_init_rcs_context function and assign in to render ring
init_context.  Moved call to intel_logical_ring_workarounds_emit into
gen8_init_rcs_context to maintain previous functionality.

Moved call to render_state_init from lr_context_deferred_create into
gen8_init_rcs_context, and modified deferred_create to call ring->init_context
for non-default contexts.

Modified i915_gem_context_enable to call ring->init_context for the default
context.

So init_context will now always be called when the hw is ready - in
i915_gem_context_enable for the default context and in lr_context_deferred_create
for other contexts.

Signed-off-by: Thomas Daniel <thomas.daniel@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

1 files changed, 18 insertions, 7 deletions

diff --git a/drivers/gpu/drm/i915/i915_gem_context.c b/drivers/gpu/drm/i915/i915_gem_context.c
index 3c3a9ff9eb54..5cd2b97aa76e 100644
--- a/drivers/gpu/drm/i915/i915_gem_context.c
+++ b/drivers/gpu/drm/i915/i915_gem_context.c
@@ -408,14 +408,25 @@ int i915_gem_context_enable(struct drm_i915_private *dev_priv)
 
 	BUG_ON(!dev_priv->ring[RCS].default_context);
 
-	if (i915.enable_execlists)
-		return 0;
+	if (i915.enable_execlists) {
+		for_each_ring(ring, dev_priv, i) {
+			if (ring->init_context) {
+				ret = ring->init_context(ring,
+						ring->default_context);
+				if (ret) {
+					DRM_ERROR("ring init context: %d\n",
+							ret);
+					return ret;
+				}
+			}
+		}
 
-	for_each_ring(ring, dev_priv, i) {
-		ret = i915_switch_context(ring, ring->default_context);
-		if (ret)
-			return ret;
-	}
+	} else
+		for_each_ring(ring, dev_priv, i) {
+			ret = i915_switch_context(ring, ring->default_context);
+			if (ret)
+				return ret;
+		}
 
 	return 0;
 }