drm/i915/gen9+: Use the watermarks from crtc_state for everything, v2.

There's no need to keep a duplicate skl_pipe_wm around any more,
everything can be discovered from crtc_state, which we pass around
correctly now even in case of plane disable.

The copy in intel_crtc->wm.skl.active is equal to
crtc_state->wm.skl.optimal after the atomic commit completes.
It's useful for two-step watermark programming, but not required for
gen9+ which does it in a single step. We can pull the old allocation
from old_crtc_state.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Cc: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1477489299-25777-9-git-send-email-maarten.lankhorst@linux.intel.com
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>

drivers/gpu/drm/i915/intel_display.c

@@ -13458,7 +13458,7 @@ static void verify_wm_state(struct drm_crtc *crtc,
 		return;
 
 	skl_pipe_wm_get_hw_state(crtc, &hw_wm);
-	sw_wm = &intel_crtc->wm.active.skl;
+	sw_wm = &to_intel_crtc_state(new_state)->wm.skl.optimal;
 
 	skl_ddb_get_hw_state(dev_priv, &hw_ddb);
 	sw_ddb = &dev_priv->wm.skl_hw.ddb;

drivers/gpu/drm/i915/intel_drv.h

@@ -722,7 +722,6 @@ struct intel_crtc {
 		/* watermarks currently being used  */
 		union {
 			struct intel_pipe_wm ilk;
-			struct skl_pipe_wm skl;
 		} active;
 
 		/* allow CxSR on this pipe */

drivers/gpu/drm/i915/intel_pm.c

@@ -3930,11 +3930,11 @@ bool skl_ddb_allocation_overlaps(struct drm_atomic_state *state,
 }
 
 static int skl_update_pipe_wm(struct drm_crtc_state *cstate,
-			      struct skl_ddb_allocation *ddb, /* out */
+			      const struct skl_pipe_wm *old_pipe_wm,
 			      struct skl_pipe_wm *pipe_wm, /* out */
+			      struct skl_ddb_allocation *ddb, /* out */
 			      bool *changed /* out */)
 {
-	struct intel_crtc *intel_crtc = to_intel_crtc(cstate->crtc);
 	struct intel_crtc_state *intel_cstate = to_intel_crtc_state(cstate);
 	int ret;
 
@@ -3942,7 +3942,7 @@ static int skl_update_pipe_wm(struct drm_crtc_state *cstate,
 	if (ret)
 		return ret;
 
-	if (!memcmp(&intel_crtc->wm.active.skl, pipe_wm, sizeof(*pipe_wm)))
+	if (!memcmp(old_pipe_wm, pipe_wm, sizeof(*pipe_wm)))
 		*changed = false;
 	else
 		*changed = true;
@@ -4169,10 +4169,12 @@ skl_compute_wm(struct drm_atomic_state *state)
 	for_each_crtc_in_state(state, crtc, cstate, i) {
 		struct intel_crtc_state *intel_cstate =
 			to_intel_crtc_state(cstate);
+		const struct skl_pipe_wm *old_pipe_wm =
+			&to_intel_crtc_state(crtc->state)->wm.skl.optimal;
 
 		pipe_wm = &intel_cstate->wm.skl.optimal;
-		ret = skl_update_pipe_wm(cstate, &results->ddb, pipe_wm,
-					 &changed);
+		ret = skl_update_pipe_wm(cstate, old_pipe_wm, pipe_wm,
+					 &results->ddb, &changed);
 		if (ret)
 			return ret;
 
@@ -4205,8 +4207,6 @@ static void skl_update_wm(struct drm_crtc *crtc)
 	if ((results->dirty_pipes & drm_crtc_mask(crtc)) == 0)
 		return;
 
-	intel_crtc->wm.active.skl = *pipe_wm;
-
 	mutex_lock(&dev_priv->wm.wm_mutex);
 
 	/*
@@ -4374,10 +4374,8 @@ void skl_wm_get_hw_state(struct drm_device *dev)
 
 		skl_pipe_wm_get_hw_state(crtc, &cstate->wm.skl.optimal);
 
-		if (intel_crtc->active) {
+		if (intel_crtc->active)
 			hw->dirty_pipes |= drm_crtc_mask(crtc);
-			intel_crtc->wm.active.skl = cstate->wm.skl.optimal;
-		}
 	}
 
 	if (dev_priv->active_crtcs) {