drm/i915/adl_p: Add dedicated SAGV watermarks

XE_LPD reduces the number of regular watermark latency levels from 8
to 6 on non-dgfx platforms.  However the hardware also adds a special
purpose SAGV wateramrk (and an accompanying transition watermark) that
will be used by the hardware in place of the level 0 values during SAGV
transitions.

Bspec: 49325, 49326, 50419
Cc: Matt Atwood <matthew.s.atwood@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Clinton Taylor <Clinton.A.Taylor@intel.com>
Reviewed-by: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210519000625.3184321-4-lucas.demarchi@intel.com
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index 15d9a64..95fda20 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -2983,7 +2983,9 @@ static void intel_fixup_cur_wm_latency(struct drm_i915_private *dev_priv,
 int ilk_wm_max_level(const struct drm_i915_private *dev_priv)
 {
 	/* how many WM levels are we expecting */
-	if (DISPLAY_VER(dev_priv) >= 9)
+	if (HAS_HW_SAGV_WM(dev_priv))
+		return 5;
+	else if (DISPLAY_VER(dev_priv) >= 9)
 		return 7;
 	else if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv))
 		return 4;
@@ -4011,8 +4013,9 @@ static int intel_compute_sagv_mask(struct intel_atomic_state *state)
 		 * latter from the plane commit hooks (especially in the legacy
 		 * cursor case)
 		 */
-		pipe_wm->use_sagv_wm = DISPLAY_VER(dev_priv) >= 12 &&
-				       intel_can_enable_sagv(dev_priv, new_bw_state);
+		pipe_wm->use_sagv_wm = !HAS_HW_SAGV_WM(dev_priv) &&
+			DISPLAY_VER(dev_priv) >= 12 &&
+			intel_can_enable_sagv(dev_priv, new_bw_state);
 	}
 
 	if (intel_can_enable_sagv(dev_priv, new_bw_state) !=
@@ -5619,6 +5622,13 @@ void skl_write_plane_wm(struct intel_plane *plane,
 	skl_write_wm_level(dev_priv, PLANE_WM_TRANS(pipe, plane_id),
 			   skl_plane_trans_wm(pipe_wm, plane_id));
 
+	if (HAS_HW_SAGV_WM(dev_priv)) {
+		skl_write_wm_level(dev_priv, PLANE_WM_SAGV(pipe, plane_id),
+				   &wm->sagv.wm0);
+		skl_write_wm_level(dev_priv, PLANE_WM_SAGV_TRANS(pipe, plane_id),
+				   &wm->sagv.trans_wm);
+	}
+
 	if (DISPLAY_VER(dev_priv) >= 11) {
 		skl_ddb_entry_write(dev_priv,
 				    PLANE_BUF_CFG(pipe, plane_id), ddb_y);
@@ -5652,6 +5662,15 @@ void skl_write_cursor_wm(struct intel_plane *plane,
 	skl_write_wm_level(dev_priv, CUR_WM_TRANS(pipe),
 			   skl_plane_trans_wm(pipe_wm, plane_id));
 
+	if (HAS_HW_SAGV_WM(dev_priv)) {
+		const struct skl_plane_wm *wm = &pipe_wm->planes[plane_id];
+
+		skl_write_wm_level(dev_priv, CUR_WM_SAGV(pipe),
+				   &wm->sagv.wm0);
+		skl_write_wm_level(dev_priv, CUR_WM_SAGV_TRANS(pipe),
+				   &wm->sagv.trans_wm);
+	}
+
 	skl_ddb_entry_write(dev_priv, CUR_BUF_CFG(pipe), ddb);
 }
 
@@ -6016,6 +6035,15 @@ static bool skl_plane_selected_wm_equals(struct intel_plane *plane,
 			return false;
 	}
 
+	if (HAS_HW_SAGV_WM(i915)) {
+		const struct skl_plane_wm *old_wm = &old_pipe_wm->planes[plane->id];
+		const struct skl_plane_wm *new_wm = &new_pipe_wm->planes[plane->id];
+
+		if (!skl_wm_level_equals(&old_wm->sagv.wm0, &new_wm->sagv.wm0) ||
+		    !skl_wm_level_equals(&old_wm->sagv.trans_wm, &new_wm->sagv.trans_wm))
+			return false;
+	}
+
 	return skl_wm_level_equals(skl_plane_trans_wm(old_pipe_wm, plane->id),
 				   skl_plane_trans_wm(new_pipe_wm, plane->id));
 }
@@ -6234,7 +6262,25 @@ void skl_pipe_wm_get_hw_state(struct intel_crtc *crtc,
 
 		skl_wm_level_from_reg_val(val, &wm->trans_wm);
 
-		if (DISPLAY_VER(dev_priv) >= 12) {
+		if (HAS_HW_SAGV_WM(dev_priv)) {
+			if (plane_id != PLANE_CURSOR)
+				val = intel_uncore_read(&dev_priv->uncore,
+							PLANE_WM_SAGV(pipe, plane_id));
+			else
+				val = intel_uncore_read(&dev_priv->uncore,
+							CUR_WM_SAGV(pipe));
+
+			skl_wm_level_from_reg_val(val, &wm->sagv.wm0);
+
+			if (plane_id != PLANE_CURSOR)
+				val = intel_uncore_read(&dev_priv->uncore,
+							PLANE_WM_SAGV_TRANS(pipe, plane_id));
+			else
+				val = intel_uncore_read(&dev_priv->uncore,
+							CUR_WM_SAGV_TRANS(pipe));
+
+			skl_wm_level_from_reg_val(val, &wm->sagv.trans_wm);
+		} else if (DISPLAY_VER(dev_priv) >= 12) {
 			wm->sagv.wm0 = wm->wm[0];
 			wm->sagv.trans_wm = wm->trans_wm;
 		}