drm/i915/bdw: GEN-specific logical ring emit request

Very similar to the legacy add_request, only modified to account for
logical ringbuffer.

v2: Use MI_GLOBAL_GTT, as suggested by Brad Volkin.

v3: Unify render and non-render in the same function, as noticed by
Brad Volkin.

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_reg.h

@@ -272,6 +272,7 @@
 #define   MI_SEMAPHORE_POLL		(1<<15)
 #define   MI_SEMAPHORE_SAD_GTE_SDD	(1<<12)
 #define MI_STORE_DWORD_IMM	MI_INSTR(0x20, 1)
+#define MI_STORE_DWORD_IMM_GEN8	MI_INSTR(0x20, 2)
 #define   MI_MEM_VIRTUAL	(1 << 22) /* 965+ only */
 #define MI_STORE_DWORD_INDEX	MI_INSTR(0x21, 1)
 #define   MI_STORE_DWORD_INDEX_SHIFT 2

drivers/gpu/drm/i915/intel_lrc.c

@@ -350,6 +350,32 @@ static void gen8_set_seqno(struct intel_engine_cs *ring, u32 seqno)
 	intel_write_status_page(ring, I915_GEM_HWS_INDEX, seqno);
 }
 
+static int gen8_emit_request(struct intel_ringbuffer *ringbuf)
+{
+	struct intel_engine_cs *ring = ringbuf->ring;
+	u32 cmd;
+	int ret;
+
+	ret = intel_logical_ring_begin(ringbuf, 6);
+	if (ret)
+		return ret;
+
+	cmd = MI_STORE_DWORD_IMM_GEN8;
+	cmd |= MI_GLOBAL_GTT;
+
+	intel_logical_ring_emit(ringbuf, cmd);
+	intel_logical_ring_emit(ringbuf,
+				(ring->status_page.gfx_addr +
+				(I915_GEM_HWS_INDEX << MI_STORE_DWORD_INDEX_SHIFT)));
+	intel_logical_ring_emit(ringbuf, 0);
+	intel_logical_ring_emit(ringbuf, ring->outstanding_lazy_seqno);
+	intel_logical_ring_emit(ringbuf, MI_USER_INTERRUPT);
+	intel_logical_ring_emit(ringbuf, MI_NOOP);
+	intel_logical_ring_advance_and_submit(ringbuf);
+
+	return 0;
+}
+
 void intel_logical_ring_cleanup(struct intel_engine_cs *ring)
 {
 	if (!intel_ring_initialized(ring))
@@ -424,6 +450,7 @@ static int logical_render_ring_init(struct drm_device *dev)
 	ring->cleanup = intel_fini_pipe_control;
 	ring->get_seqno = gen8_get_seqno;
 	ring->set_seqno = gen8_set_seqno;
+	ring->emit_request = gen8_emit_request;
 
 	return logical_ring_init(dev, ring);
 }
@@ -442,6 +469,7 @@ static int logical_bsd_ring_init(struct drm_device *dev)
 	ring->init = gen8_init_common_ring;
 	ring->get_seqno = gen8_get_seqno;
 	ring->set_seqno = gen8_set_seqno;
+	ring->emit_request = gen8_emit_request;
 
 	return logical_ring_init(dev, ring);
 }
@@ -460,6 +488,7 @@ static int logical_bsd2_ring_init(struct drm_device *dev)
 	ring->init = gen8_init_common_ring;
 	ring->get_seqno = gen8_get_seqno;
 	ring->set_seqno = gen8_set_seqno;
+	ring->emit_request = gen8_emit_request;
 
 	return logical_ring_init(dev, ring);
 }
@@ -478,6 +507,7 @@ static int logical_blt_ring_init(struct drm_device *dev)
 	ring->init = gen8_init_common_ring;
 	ring->get_seqno = gen8_get_seqno;
 	ring->set_seqno = gen8_set_seqno;
+	ring->emit_request = gen8_emit_request;
 
 	return logical_ring_init(dev, ring);
 }
@@ -496,6 +526,7 @@ static int logical_vebox_ring_init(struct drm_device *dev)
 	ring->init = gen8_init_common_ring;
 	ring->get_seqno = gen8_get_seqno;
 	ring->set_seqno = gen8_set_seqno;
+	ring->emit_request = gen8_emit_request;
 
 	return logical_ring_init(dev, ring);
 }

drivers/gpu/drm/i915/intel_ringbuffer.h

@@ -216,6 +216,9 @@ struct  intel_engine_cs {
 				  unsigned int num_dwords);
 	} semaphore;
 
+	/* Execlists */
+	int		(*emit_request)(struct intel_ringbuffer *ringbuf);
+
 	/**
 	 * List of objects currently involved in rendering from the
 	 * ringbuffer.