drm/i915: constify display wm vtable

Use a nop table for the cases where CxSR doesn't init properly.

v2: use a nop table (Jani)
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/bb0658d14afd02cca692cd58223800f68f4ff4ce.1632869550.git.jani.nikula@intel.com

drivers/gpu/drm/i915/display/intel_display.c

@@ -161,16 +161,16 @@ static void intel_modeset_setup_hw_state(struct drm_device *dev,
  */
 static void intel_update_watermarks(struct drm_i915_private *dev_priv)
 {
-	if (dev_priv->wm_disp.update_wm)
-		dev_priv->wm_disp.update_wm(dev_priv);
+	if (dev_priv->wm_disp->update_wm)
+		dev_priv->wm_disp->update_wm(dev_priv);
 }
 
 static int intel_compute_pipe_wm(struct intel_atomic_state *state,
 				 struct intel_crtc *crtc)
 {
 	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
-	if (dev_priv->wm_disp.compute_pipe_wm)
-		return dev_priv->wm_disp.compute_pipe_wm(state, crtc);
+	if (dev_priv->wm_disp->compute_pipe_wm)
+		return dev_priv->wm_disp->compute_pipe_wm(state, crtc);
 	return 0;
 }
 
@@ -178,20 +178,20 @@ static int intel_compute_intermediate_wm(struct intel_atomic_state *state,
 					 struct intel_crtc *crtc)
 {
 	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
-	if (!dev_priv->wm_disp.compute_intermediate_wm)
+	if (!dev_priv->wm_disp->compute_intermediate_wm)
 		return 0;
 	if (drm_WARN_ON(&dev_priv->drm,
-			!dev_priv->wm_disp.compute_pipe_wm))
+			!dev_priv->wm_disp->compute_pipe_wm))
 		return 0;
-	return dev_priv->wm_disp.compute_intermediate_wm(state, crtc);
+	return dev_priv->wm_disp->compute_intermediate_wm(state, crtc);
 }
 
 static bool intel_initial_watermarks(struct intel_atomic_state *state,
 				     struct intel_crtc *crtc)
 {
 	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
-	if (dev_priv->wm_disp.initial_watermarks) {
-		dev_priv->wm_disp.initial_watermarks(state, crtc);
+	if (dev_priv->wm_disp->initial_watermarks) {
+		dev_priv->wm_disp->initial_watermarks(state, crtc);
 		return true;
 	}
 	return false;
@@ -201,23 +201,23 @@ static void intel_atomic_update_watermarks(struct intel_atomic_state *state,
 					   struct intel_crtc *crtc)
 {
 	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
-	if (dev_priv->wm_disp.atomic_update_watermarks)
-		dev_priv->wm_disp.atomic_update_watermarks(state, crtc);
+	if (dev_priv->wm_disp->atomic_update_watermarks)
+		dev_priv->wm_disp->atomic_update_watermarks(state, crtc);
 }
 
 static void intel_optimize_watermarks(struct intel_atomic_state *state,
 				      struct intel_crtc *crtc)
 {
 	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
-	if (dev_priv->wm_disp.optimize_watermarks)
-		dev_priv->wm_disp.optimize_watermarks(state, crtc);
+	if (dev_priv->wm_disp->optimize_watermarks)
+		dev_priv->wm_disp->optimize_watermarks(state, crtc);
 }
 
 static int intel_compute_global_watermarks(struct intel_atomic_state *state)
 {
 	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
-	if (dev_priv->wm_disp.compute_global_watermarks)
-		return dev_priv->wm_disp.compute_global_watermarks(state);
+	if (dev_priv->wm_disp->compute_global_watermarks)
+		return dev_priv->wm_disp->compute_global_watermarks(state);
 	return 0;
 }
 
@@ -3743,7 +3743,7 @@ static void i9xx_crtc_disable(struct intel_atomic_state *state,
 	if (DISPLAY_VER(dev_priv) != 2)
 		intel_set_cpu_fifo_underrun_reporting(dev_priv, pipe, false);
 
-	if (!dev_priv->wm_disp.initial_watermarks)
+	if (!dev_priv->wm_disp->initial_watermarks)
 		intel_update_watermarks(dev_priv);
 
 	/* clock the pipe down to 640x480@60 to potentially save power */
@@ -11425,7 +11425,7 @@ static void sanitize_watermarks(struct drm_i915_private *dev_priv)
 	int i;
 
 	/* Only supported on platforms that use atomic watermark design */
-	if (!dev_priv->wm_disp.optimize_watermarks)
+	if (!dev_priv->wm_disp->optimize_watermarks)
 		return;
 
 	state = drm_atomic_state_alloc(&dev_priv->drm);

drivers/gpu/drm/i915/i915_drv.h

@@ -978,7 +978,7 @@ struct drm_i915_private {
 	const struct drm_i915_clock_gating_funcs *clock_gating_funcs;
 
 	/* pm display functions */
-	struct drm_i915_wm_disp_funcs wm_disp;
+	const struct drm_i915_wm_disp_funcs *wm_disp;
 
 	/* irq display functions */
 	const struct intel_hotplug_funcs *hotplug_funcs;

drivers/gpu/drm/i915/intel_pm.c

@@ -7975,6 +7975,51 @@ void intel_init_clock_gating_hooks(struct drm_i915_private *dev_priv)
 	}
 }
 
+static const struct drm_i915_wm_disp_funcs skl_wm_funcs = {
+	.compute_global_watermarks = skl_compute_wm,
+};
+
+static const struct drm_i915_wm_disp_funcs ilk_wm_funcs = {
+	.compute_pipe_wm = ilk_compute_pipe_wm,
+	.compute_intermediate_wm = ilk_compute_intermediate_wm,
+	.initial_watermarks = ilk_initial_watermarks,
+	.optimize_watermarks = ilk_optimize_watermarks,
+};
+
+static const struct drm_i915_wm_disp_funcs vlv_wm_funcs = {
+	.compute_pipe_wm = vlv_compute_pipe_wm,
+	.compute_intermediate_wm = vlv_compute_intermediate_wm,
+	.initial_watermarks = vlv_initial_watermarks,
+	.optimize_watermarks = vlv_optimize_watermarks,
+	.atomic_update_watermarks = vlv_atomic_update_fifo,
+};
+
+static const struct drm_i915_wm_disp_funcs g4x_wm_funcs = {
+	.compute_pipe_wm = g4x_compute_pipe_wm,
+	.compute_intermediate_wm = g4x_compute_intermediate_wm,
+	.initial_watermarks = g4x_initial_watermarks,
+	.optimize_watermarks = g4x_optimize_watermarks,
+};
+
+static const struct drm_i915_wm_disp_funcs pnv_wm_funcs = {
+	.update_wm = pnv_update_wm,
+};
+
+static const struct drm_i915_wm_disp_funcs i965_wm_funcs = {
+	.update_wm = i965_update_wm,
+};
+
+static const struct drm_i915_wm_disp_funcs i9xx_wm_funcs = {
+	.update_wm = i9xx_update_wm,
+};
+
+static const struct drm_i915_wm_disp_funcs i845_wm_funcs = {
+	.update_wm = i845_update_wm,
+};
+
+static const struct drm_i915_wm_disp_funcs nop_funcs = {
+};
+
 /* Set up chip specific power management-related functions */
 void intel_init_pm(struct drm_i915_private *dev_priv)
 {
@@ -7990,7 +8035,7 @@ void intel_init_pm(struct drm_i915_private *dev_priv)
 	/* For FIFO watermark updates */
 	if (DISPLAY_VER(dev_priv) >= 9) {
 		skl_setup_wm_latency(dev_priv);
-		dev_priv->wm_disp.compute_global_watermarks = skl_compute_wm;
+		dev_priv->wm_disp = &skl_wm_funcs;
 	} else if (HAS_PCH_SPLIT(dev_priv)) {
 		ilk_setup_wm_latency(dev_priv);
 
@@ -7998,31 +8043,19 @@ void intel_init_pm(struct drm_i915_private *dev_priv)
 		     dev_priv->wm.spr_latency[1] && dev_priv->wm.cur_latency[1]) ||
 		    (DISPLAY_VER(dev_priv) != 5 && dev_priv->wm.pri_latency[0] &&
 		     dev_priv->wm.spr_latency[0] && dev_priv->wm.cur_latency[0])) {
-			dev_priv->wm_disp.compute_pipe_wm = ilk_compute_pipe_wm;
-			dev_priv->wm_disp.compute_intermediate_wm =
-				ilk_compute_intermediate_wm;
-			dev_priv->wm_disp.initial_watermarks =
-				ilk_initial_watermarks;
-			dev_priv->wm_disp.optimize_watermarks =
-				ilk_optimize_watermarks;
+			dev_priv->wm_disp = &ilk_wm_funcs;
 		} else {
 			drm_dbg_kms(&dev_priv->drm,
 				    "Failed to read display plane latency. "
 				    "Disable CxSR\n");
+			dev_priv->wm_disp = &nop_funcs;
 		}
 	} else if (IS_VALLEYVIEW(dev_priv) || IS_CHERRYVIEW(dev_priv)) {
 		vlv_setup_wm_latency(dev_priv);
-		dev_priv->wm_disp.compute_pipe_wm = vlv_compute_pipe_wm;
-		dev_priv->wm_disp.compute_intermediate_wm = vlv_compute_intermediate_wm;
-		dev_priv->wm_disp.initial_watermarks = vlv_initial_watermarks;
-		dev_priv->wm_disp.optimize_watermarks = vlv_optimize_watermarks;
-		dev_priv->wm_disp.atomic_update_watermarks = vlv_atomic_update_fifo;
+		dev_priv->wm_disp = &vlv_wm_funcs;
 	} else if (IS_G4X(dev_priv)) {
 		g4x_setup_wm_latency(dev_priv);
-		dev_priv->wm_disp.compute_pipe_wm = g4x_compute_pipe_wm;
-		dev_priv->wm_disp.compute_intermediate_wm = g4x_compute_intermediate_wm;
-		dev_priv->wm_disp.initial_watermarks = g4x_initial_watermarks;
-		dev_priv->wm_disp.optimize_watermarks = g4x_optimize_watermarks;
+		dev_priv->wm_disp = &g4x_wm_funcs;
 	} else if (IS_PINEVIEW(dev_priv)) {
 		if (!intel_get_cxsr_latency(!IS_MOBILE(dev_priv),
 					    dev_priv->is_ddr3,
@@ -8036,21 +8069,22 @@ void intel_init_pm(struct drm_i915_private *dev_priv)
 				 dev_priv->fsb_freq, dev_priv->mem_freq);
 			/* Disable CxSR and never update its watermark again */
 			intel_set_memory_cxsr(dev_priv, false);
-			dev_priv->wm_disp.update_wm = NULL;
+			dev_priv->wm_disp = &nop_funcs;
 		} else
-			dev_priv->wm_disp.update_wm = pnv_update_wm;
+			dev_priv->wm_disp = &pnv_wm_funcs;
 	} else if (DISPLAY_VER(dev_priv) == 4) {
-		dev_priv->wm_disp.update_wm = i965_update_wm;
+		dev_priv->wm_disp = &i965_wm_funcs;
 	} else if (DISPLAY_VER(dev_priv) == 3) {
-		dev_priv->wm_disp.update_wm = i9xx_update_wm;
+		dev_priv->wm_disp = &i9xx_wm_funcs;
 	} else if (DISPLAY_VER(dev_priv) == 2) {
 		if (INTEL_NUM_PIPES(dev_priv) == 1)
-			dev_priv->wm_disp.update_wm = i845_update_wm;
+			dev_priv->wm_disp = &i845_wm_funcs;
 		else
-			dev_priv->wm_disp.update_wm = i9xx_update_wm;
+			dev_priv->wm_disp = &i9xx_wm_funcs;
 	} else {
 		drm_err(&dev_priv->drm,
 			"unexpected fall-through in %s\n", __func__);
+		dev_priv->wm_disp = &nop_funcs;
 	}
 }