drm/i915/skl: Implement queue_flip

A few bits have changed in MI_DISPLAY_FLIP to accomodate the new planes.
DE_RRMR seems to have kept its plane flip bits backward compatible.

v2: Rebase on top of nightly
v3: Rebase on top of nightly (minor conflict in i915_reg.h)
v4: Remove code that is now part of intel_crtc_page_flip()
    Don't use BUG() in default:
    Use intel_crtc->unpin_work->gtt_offset
    (Paulo)
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Damien Lespiau <damien.lespiau@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

drivers/gpu/drm/i915/i915_reg.h

@@ -248,6 +248,16 @@
 #define   MI_DISPLAY_FLIP_IVB_SPRITE_B (3 << 19)
 #define   MI_DISPLAY_FLIP_IVB_PLANE_C  (4 << 19)
 #define   MI_DISPLAY_FLIP_IVB_SPRITE_C (5 << 19)
+/* SKL ones */
+#define   MI_DISPLAY_FLIP_SKL_PLANE_1_A	(0 << 8)
+#define   MI_DISPLAY_FLIP_SKL_PLANE_1_B	(1 << 8)
+#define   MI_DISPLAY_FLIP_SKL_PLANE_1_C	(2 << 8)
+#define   MI_DISPLAY_FLIP_SKL_PLANE_2_A	(4 << 8)
+#define   MI_DISPLAY_FLIP_SKL_PLANE_2_B	(5 << 8)
+#define   MI_DISPLAY_FLIP_SKL_PLANE_2_C	(6 << 8)
+#define   MI_DISPLAY_FLIP_SKL_PLANE_3_A	(7 << 8)
+#define   MI_DISPLAY_FLIP_SKL_PLANE_3_B	(8 << 8)
+#define   MI_DISPLAY_FLIP_SKL_PLANE_3_C	(9 << 8)
 #define MI_SEMAPHORE_MBOX	MI_INSTR(0x16, 1) /* gen6, gen7 */
 #define   MI_SEMAPHORE_GLOBAL_GTT    (1<<22)
 #define   MI_SEMAPHORE_UPDATE	    (1<<21)

drivers/gpu/drm/i915/intel_display.c

@@ -9480,6 +9480,69 @@ static int intel_queue_mmio_flip(struct drm_device *dev,
 	return 0;
 }
 
+static int intel_gen9_queue_flip(struct drm_device *dev,
+				 struct drm_crtc *crtc,
+				 struct drm_framebuffer *fb,
+				 struct drm_i915_gem_object *obj,
+				 struct intel_engine_cs *ring,
+				 uint32_t flags)
+{
+	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
+	uint32_t plane = 0, stride;
+	int ret;
+
+	switch(intel_crtc->pipe) {
+	case PIPE_A:
+		plane = MI_DISPLAY_FLIP_SKL_PLANE_1_A;
+		break;
+	case PIPE_B:
+		plane = MI_DISPLAY_FLIP_SKL_PLANE_1_B;
+		break;
+	case PIPE_C:
+		plane = MI_DISPLAY_FLIP_SKL_PLANE_1_C;
+		break;
+	default:
+		WARN_ONCE(1, "unknown plane in flip command\n");
+		return -ENODEV;
+	}
+
+	switch (obj->tiling_mode) {
+	case I915_TILING_NONE:
+		stride = fb->pitches[0] >> 6;
+		break;
+	case I915_TILING_X:
+		stride = fb->pitches[0] >> 9;
+		break;
+	default:
+		WARN_ONCE(1, "unknown tiling in flip command\n");
+		return -ENODEV;
+	}
+
+	ret = intel_ring_begin(ring, 10);
+	if (ret)
+		return ret;
+
+	intel_ring_emit(ring, MI_LOAD_REGISTER_IMM(1));
+	intel_ring_emit(ring, DERRMR);
+	intel_ring_emit(ring, ~(DERRMR_PIPEA_PRI_FLIP_DONE |
+				DERRMR_PIPEB_PRI_FLIP_DONE |
+				DERRMR_PIPEC_PRI_FLIP_DONE));
+	intel_ring_emit(ring, MI_STORE_REGISTER_MEM_GEN8(1) |
+			      MI_SRM_LRM_GLOBAL_GTT);
+	intel_ring_emit(ring, DERRMR);
+	intel_ring_emit(ring, ring->scratch.gtt_offset + 256);
+	intel_ring_emit(ring, 0);
+
+	intel_ring_emit(ring, MI_DISPLAY_FLIP_I915 | plane);
+	intel_ring_emit(ring, stride << 6 | obj->tiling_mode);
+	intel_ring_emit(ring, intel_crtc->unpin_work->gtt_offset);
+
+	intel_mark_page_flip_active(intel_crtc);
+	__intel_ring_advance(ring);
+
+	return 0;
+}
+
 static int intel_default_queue_flip(struct drm_device *dev,
 				    struct drm_crtc *crtc,
 				    struct drm_framebuffer *fb,
@@ -12648,6 +12711,9 @@ static void intel_init_display(struct drm_device *dev)
 	case 8: /* FIXME(BDW): Check that the gen8 RCS flip works. */
 		dev_priv->display.queue_flip = intel_gen7_queue_flip;
 		break;
+	case 9:
+		dev_priv->display.queue_flip = intel_gen9_queue_flip;
+		break;
 	}
 
 	intel_panel_init_backlight_funcs(dev);