drm/i915: Eliminate obj->state usage in g4x/vlv/chv wm computation

Use explicit old/new states instead of relying on obj->state.
Reviewed-by: NMaarten Lankhorst <maarten.lankhorst@linux.intel.com>
Signed-off-by: NVille Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20170823152226.22938-4-ville.syrjala@linux.intel.com

drivers/gpu/drm/i915/i915_drv.h

@@ -578,6 +578,15 @@ struct i915_hotplug {
 		for_each_if (crtc)
 
 
+#define for_each_oldnew_intel_plane_in_state(__state, plane, old_plane_state, new_plane_state, __i) \
+	for ((__i) = 0; \
+	     (__i) < (__state)->base.dev->mode_config.num_total_plane && \
+		     ((plane) = to_intel_plane((__state)->base.planes[__i].ptr), \
+		      (old_plane_state) = to_intel_plane_state((__state)->base.planes[__i].old_state), \
+		      (new_plane_state) = to_intel_plane_state((__state)->base.planes[__i].new_state), 1); \
+	     (__i)++) \
+		for_each_if (plane)
+
 struct drm_i915_private;
 struct i915_mm_struct;
 struct i915_mmu_object;

drivers/gpu/drm/i915/intel_drv.h

@@ -1192,6 +1192,14 @@ hdmi_to_dig_port(struct intel_hdmi *intel_hdmi)
 	return container_of(intel_hdmi, struct intel_digital_port, hdmi);
 }
 
+static inline struct intel_crtc_state *
+intel_atomic_get_old_crtc_state(struct intel_atomic_state *state,
+				struct intel_crtc *crtc)
+{
+	return to_intel_crtc_state(drm_atomic_get_old_crtc_state(&state->base,
+								 &crtc->base));
+}
+
 static inline struct intel_crtc_state *
 intel_atomic_get_new_crtc_state(struct intel_atomic_state *state,
 				struct intel_crtc *crtc)

drivers/gpu/drm/i915/intel_pm.c

@@ -1322,21 +1322,21 @@ static int g4x_compute_pipe_wm(struct intel_crtc_state *crtc_state)
 	int num_active_planes = hweight32(crtc_state->active_planes &
 					  ~BIT(PLANE_CURSOR));
 	const struct g4x_pipe_wm *raw;
-	struct intel_plane_state *plane_state;
+	const struct intel_plane_state *old_plane_state;
+	const struct intel_plane_state *new_plane_state;
 	struct intel_plane *plane;
 	enum plane_id plane_id;
 	int i, level;
 	unsigned int dirty = 0;
 
-	for_each_intel_plane_in_state(state, plane, plane_state, i) {
-		const struct intel_plane_state *old_plane_state =
-			to_intel_plane_state(plane->base.state);
-
-		if (plane_state->base.crtc != &crtc->base &&
+	for_each_oldnew_intel_plane_in_state(state, plane,
+					     old_plane_state,
+					     new_plane_state, i) {
+		if (new_plane_state->base.crtc != &crtc->base &&
 		    old_plane_state->base.crtc != &crtc->base)
 			continue;
 
-		if (g4x_raw_plane_wm_compute(crtc_state, plane_state))
+		if (g4x_raw_plane_wm_compute(crtc_state, new_plane_state))
 			dirty |= BIT(plane->id);
 	}
 
@@ -1831,21 +1831,21 @@ static int vlv_compute_pipe_wm(struct intel_crtc_state *crtc_state)
 	int num_active_planes = hweight32(crtc_state->active_planes &
 					  ~BIT(PLANE_CURSOR));
 	bool needs_modeset = drm_atomic_crtc_needs_modeset(&crtc_state->base);
-	struct intel_plane_state *plane_state;
+	const struct intel_plane_state *old_plane_state;
+	const struct intel_plane_state *new_plane_state;
 	struct intel_plane *plane;
 	enum plane_id plane_id;
 	int level, ret, i;
 	unsigned int dirty = 0;
 
-	for_each_intel_plane_in_state(state, plane, plane_state, i) {
-		const struct intel_plane_state *old_plane_state =
-			to_intel_plane_state(plane->base.state);
-
-		if (plane_state->base.crtc != &crtc->base &&
+	for_each_oldnew_intel_plane_in_state(state, plane,
+					     old_plane_state,
+					     new_plane_state, i) {
+		if (new_plane_state->base.crtc != &crtc->base &&
 		    old_plane_state->base.crtc != &crtc->base)
 			continue;
 
-		if (vlv_raw_plane_wm_compute(crtc_state, plane_state))
+		if (vlv_raw_plane_wm_compute(crtc_state, new_plane_state))
 			dirty |= BIT(plane->id);
 	}
 
@@ -1864,7 +1864,7 @@ static int vlv_compute_pipe_wm(struct intel_crtc_state *crtc_state)
 	/* cursor changes don't warrant a FIFO recompute */
 	if (dirty & ~BIT(PLANE_CURSOR)) {
 		const struct intel_crtc_state *old_crtc_state =
-			to_intel_crtc_state(crtc->base.state);
+			intel_atomic_get_old_crtc_state(state, crtc);
 		const struct vlv_fifo_state *old_fifo_state =
 			&old_crtc_state->wm.vlv.fifo_state;