drm/i915: Fix gen8 semaphores id for legacy mode

With the introduction of a distinct engine->id vs the hardware id, we need
to fix up the value we use for selecting the target engine when signaling
a semaphore. Note that these values can be merged with engine->guc_id.

Fixes: de1add3
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1461932305-14637-3-git-send-email-chris@chris-wilson.co.uk

drivers/gpu/drm/i915/intel_ringbuffer.c

@@ -1313,7 +1313,7 @@ static int gen8_rcs_signal(struct drm_i915_gem_request *signaller_req,
 		intel_ring_emit(signaller, seqno);
 		intel_ring_emit(signaller, 0);
 		intel_ring_emit(signaller, MI_SEMAPHORE_SIGNAL |
-					   MI_SEMAPHORE_TARGET(waiter->id));
+					   MI_SEMAPHORE_TARGET(waiter->hw_id));
 		intel_ring_emit(signaller, 0);
 	}
 
@@ -1353,7 +1353,7 @@ static int gen8_xcs_signal(struct drm_i915_gem_request *signaller_req,
 		intel_ring_emit(signaller, upper_32_bits(gtt_offset));
 		intel_ring_emit(signaller, seqno);
 		intel_ring_emit(signaller, MI_SEMAPHORE_SIGNAL |
-					   MI_SEMAPHORE_TARGET(waiter->id));
+					   MI_SEMAPHORE_TARGET(waiter->hw_id));
 		intel_ring_emit(signaller, 0);
 	}
 
@@ -2759,6 +2759,7 @@ int intel_init_render_ring_buffer(struct drm_device *dev)
 	engine->name = "render ring";
 	engine->id = RCS;
 	engine->exec_id = I915_EXEC_RENDER;
+	engine->hw_id = 0;
 	engine->mmio_base = RENDER_RING_BASE;
 
 	if (INTEL_INFO(dev)->gen >= 8) {
@@ -2909,6 +2910,7 @@ int intel_init_bsd_ring_buffer(struct drm_device *dev)
 	engine->name = "bsd ring";
 	engine->id = VCS;
 	engine->exec_id = I915_EXEC_BSD;
+	engine->hw_id = 1;
 
 	engine->write_tail = ring_write_tail;
 	if (INTEL_INFO(dev)->gen >= 6) {
@@ -2987,6 +2989,7 @@ int intel_init_bsd2_ring_buffer(struct drm_device *dev)
 	engine->name = "bsd2 ring";
 	engine->id = VCS2;
 	engine->exec_id = I915_EXEC_BSD;
+	engine->hw_id = 4;
 
 	engine->write_tail = ring_write_tail;
 	engine->mmio_base = GEN8_BSD2_RING_BASE;
@@ -3019,6 +3022,7 @@ int intel_init_blt_ring_buffer(struct drm_device *dev)
 	engine->name = "blitter ring";
 	engine->id = BCS;
 	engine->exec_id = I915_EXEC_BLT;
+	engine->hw_id = 2;
 
 	engine->mmio_base = BLT_RING_BASE;
 	engine->write_tail = ring_write_tail;
@@ -3078,6 +3082,7 @@ int intel_init_vebox_ring_buffer(struct drm_device *dev)
 	engine->name = "video enhancement ring";
 	engine->id = VECS;
 	engine->exec_id = I915_EXEC_VEBOX;
+	engine->hw_id = 3;
 
 	engine->mmio_base = VEBOX_RING_BASE;
 	engine->write_tail = ring_write_tail;

drivers/gpu/drm/i915/intel_ringbuffer.h

@@ -153,7 +153,8 @@ struct  intel_engine_cs {
 #define I915_NUM_ENGINES 5
 #define _VCS(n) (VCS + (n))
 	unsigned int exec_id;
-	unsigned int guc_id;
+	unsigned int hw_id;
+	unsigned int guc_id; /* XXX same as hw_id? */
 	u32		mmio_base;
 	struct		drm_device *dev;
 	struct intel_ringbuffer *buffer;