drm/i915: Calculate pipe watermarks into CRTC state (v3)

A future patch will calculate these during the atomic 'check' phase
rather than at WM programming time, so let's store the watermark
values we're planning to use in the CRTC state; the values actually
active on the hardware remains in intel_crtc.

While we're at it, do some minor restructuring to keep ILK and SKL
values in a union.

v2: Don't move cxsr_allowed to state (Maarten)

v3: Only calculate watermarks in state.  Still keep active watermarks in
    intel_crtc itself.  (Ville)
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Smoke-tested-by: Paulo Zanoni <przanoni@gmail.com>
Link: http://patchwork.freedesktop.org/patch/59556/

drivers/gpu/drm/i915/intel_drv.h

@@ -334,6 +334,21 @@ struct intel_crtc_scaler_state {
 /* drm_mode->private_flags */
 #define I915_MODE_FLAG_INHERITED 1
 
+struct intel_pipe_wm {
+	struct intel_wm_level wm[5];
+	uint32_t linetime;
+	bool fbc_wm_enabled;
+	bool pipe_enabled;
+	bool sprites_enabled;
+	bool sprites_scaled;
+};
+
+struct skl_pipe_wm {
+	struct skl_wm_level wm[8];
+	struct skl_wm_level trans_wm;
+	uint32_t linetime;
+};
+
 struct intel_crtc_state {
 	struct drm_crtc_state base;
 
@@ -471,6 +486,17 @@ struct intel_crtc_state {
 
 	/* IVB sprite scaling w/a (WaCxSRDisabledForSpriteScaling:ivb) */
 	bool disable_lp_wm;
+
+	struct {
+		/*
+		 * optimal watermarks, programmed post-vblank when this state
+		 * is committed
+		 */
+		union {
+			struct intel_pipe_wm ilk;
+			struct skl_pipe_wm skl;
+		} optimal;
+	} wm;
 };
 
 struct vlv_wm_state {
@@ -482,15 +508,6 @@ struct vlv_wm_state {
 	bool cxsr;
 };
 
-struct intel_pipe_wm {
-	struct intel_wm_level wm[5];
-	uint32_t linetime;
-	bool fbc_wm_enabled;
-	bool pipe_enabled;
-	bool sprites_enabled;
-	bool sprites_scaled;
-};
-
 struct intel_mmio_flip {
 	struct work_struct work;
 	struct drm_i915_private *i915;
@@ -499,12 +516,6 @@ struct intel_mmio_flip {
 	unsigned int rotation;
 };
 
-struct skl_pipe_wm {
-	struct skl_wm_level wm[8];
-	struct skl_wm_level trans_wm;
-	uint32_t linetime;
-};
-
 /*
  * Tracking of operations that need to be performed at the beginning/end of an
  * atomic commit, outside the atomic section where interrupts are disabled.
@@ -571,9 +582,10 @@ struct intel_crtc {
 	/* per-pipe watermark state */
 	struct {
 		/* watermarks currently being used  */
-		struct intel_pipe_wm active;
-		/* SKL wm values currently in use */
-		struct skl_pipe_wm skl_active;
+		union {
+			struct intel_pipe_wm ilk;
+			struct skl_pipe_wm skl;
+		} active;
 		/* allow CxSR on this pipe */
 		bool cxsr_allowed;
 	} wm;

drivers/gpu/drm/i915/intel_pm.c

@@ -2274,7 +2274,7 @@ static void ilk_compute_wm_config(struct drm_device *dev,
 
 	/* Compute the currently _active_ config */
 	for_each_intel_crtc(dev, intel_crtc) {
-		const struct intel_pipe_wm *wm = &intel_crtc->wm.active;
+		const struct intel_pipe_wm *wm = &intel_crtc->wm.active.ilk;
 
 		if (!wm->pipe_enabled)
 			continue;
@@ -2371,7 +2371,9 @@ static void ilk_merge_wm_level(struct drm_device *dev,
 	ret_wm->enable = true;
 
 	for_each_intel_crtc(dev, intel_crtc) {
-		const struct intel_pipe_wm *active = &intel_crtc->wm.active;
+		const struct intel_crtc_state *cstate =
+			to_intel_crtc_state(intel_crtc->base.state);
+		const struct intel_pipe_wm *active = &cstate->wm.optimal.ilk;
 		const struct intel_wm_level *wm = &active->wm[level];
 
 		if (!active->pipe_enabled)
@@ -2519,14 +2521,15 @@ static void ilk_compute_wm_results(struct drm_device *dev,
 
 	/* LP0 register values */
 	for_each_intel_crtc(dev, intel_crtc) {
+		const struct intel_crtc_state *cstate =
+			to_intel_crtc_state(intel_crtc->base.state);
 		enum pipe pipe = intel_crtc->pipe;
-		const struct intel_wm_level *r =
-			&intel_crtc->wm.active.wm[0];
+		const struct intel_wm_level *r = &cstate->wm.optimal.ilk.wm[0];
 
 		if (WARN_ON(!r->enable))
 			continue;
 
-		results->wm_linetime[pipe] = intel_crtc->wm.active.linetime;
+		results->wm_linetime[pipe] = cstate->wm.optimal.ilk.linetime;
 
 		results->wm_pipe[pipe] =
 			(r->pri_val << WM0_PIPE_PLANE_SHIFT) |
@@ -3511,10 +3514,10 @@ static bool skl_update_pipe_wm(struct drm_crtc *crtc,
 	skl_allocate_pipe_ddb(cstate, config, ddb);
 	skl_compute_pipe_wm(cstate, ddb, pipe_wm);
 
-	if (!memcmp(&intel_crtc->wm.skl_active, pipe_wm, sizeof(*pipe_wm)))
+	if (!memcmp(&intel_crtc->wm.active.skl, pipe_wm, sizeof(*pipe_wm)))
 		return false;
 
-	intel_crtc->wm.skl_active = *pipe_wm;
+	intel_crtc->wm.active.skl = *pipe_wm;
 
 	return true;
 }
@@ -3592,7 +3595,8 @@ static void skl_update_wm(struct drm_crtc *crtc)
 	struct drm_device *dev = crtc->dev;
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct skl_wm_values *results = &dev_priv->wm.skl_results;
-	struct skl_pipe_wm pipe_wm = {};
+	struct intel_crtc_state *cstate = to_intel_crtc_state(crtc->state);
+	struct skl_pipe_wm *pipe_wm = &cstate->wm.optimal.skl;
 	struct intel_wm_config config = {};
 
 
@@ -3603,10 +3607,10 @@ static void skl_update_wm(struct drm_crtc *crtc)
 
 	skl_compute_wm_global_parameters(dev, &config);
 
-	if (!skl_update_pipe_wm(crtc, &config, &results->ddb, &pipe_wm))
+	if (!skl_update_pipe_wm(crtc, &config, &results->ddb, pipe_wm))
 		return;
 
-	skl_compute_wm_results(dev, &pipe_wm, results, intel_crtc);
+	skl_compute_wm_results(dev, pipe_wm, results, intel_crtc);
 	results->dirty[intel_crtc->pipe] = true;
 
 	skl_update_other_pipe_wm(dev, crtc, &config, results);
@@ -3655,7 +3659,6 @@ static void ilk_update_wm(struct drm_crtc *crtc)
 	struct drm_i915_private *dev_priv = to_i915(crtc->dev);
 	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
 	struct intel_crtc_state *cstate = to_intel_crtc_state(crtc->state);
-	struct intel_pipe_wm pipe_wm = {};
 
 	WARN_ON(cstate->base.active != intel_crtc->active);
 
@@ -3671,12 +3674,13 @@ static void ilk_update_wm(struct drm_crtc *crtc)
 		intel_wait_for_vblank(crtc->dev, intel_crtc->pipe);
 	}
 
-	intel_compute_pipe_wm(cstate, &pipe_wm);
+	intel_compute_pipe_wm(cstate, &cstate->wm.optimal.ilk);
 
-	if (!memcmp(&intel_crtc->wm.active, &pipe_wm, sizeof(pipe_wm)))
-		return;
+	if (!memcmp(&intel_crtc->wm.active.ilk,
+		    &cstate->wm.optimal.ilk,
+		    sizeof(cstate->wm.optimal.ilk)));
 
-	intel_crtc->wm.active = pipe_wm;
+	intel_crtc->wm.active.ilk = cstate->wm.optimal.ilk;
 
 	ilk_program_watermarks(dev_priv);
 }
@@ -3731,7 +3735,8 @@ static void skl_pipe_wm_get_hw_state(struct drm_crtc *crtc)
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct skl_wm_values *hw = &dev_priv->wm.skl_hw;
 	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
-	struct skl_pipe_wm *active = &intel_crtc->wm.skl_active;
+	struct intel_crtc_state *cstate = to_intel_crtc_state(crtc->state);
+	struct skl_pipe_wm *active = &cstate->wm.optimal.skl;
 	enum pipe pipe = intel_crtc->pipe;
 	int level, i, max_level;
 	uint32_t temp;
@@ -3775,6 +3780,8 @@ static void skl_pipe_wm_get_hw_state(struct drm_crtc *crtc)
 
 	temp = hw->plane_trans[pipe][PLANE_CURSOR];
 	skl_pipe_wm_active_state(temp, active, true, true, i, 0);
+
+	intel_crtc->wm.active.skl = *active;
 }
 
 void skl_wm_get_hw_state(struct drm_device *dev)
@@ -3794,7 +3801,8 @@ static void ilk_pipe_wm_get_hw_state(struct drm_crtc *crtc)
 	struct drm_i915_private *dev_priv = dev->dev_private;
 	struct ilk_wm_values *hw = &dev_priv->wm.hw;
 	struct intel_crtc *intel_crtc = to_intel_crtc(crtc);
-	struct intel_pipe_wm *active = &intel_crtc->wm.active;
+	struct intel_crtc_state *cstate = to_intel_crtc_state(crtc->state);
+	struct intel_pipe_wm *active = &cstate->wm.optimal.ilk;
 	enum pipe pipe = intel_crtc->pipe;
 	static const unsigned int wm0_pipe_reg[] = {
 		[PIPE_A] = WM0_PIPEA_ILK,
@@ -3833,6 +3841,8 @@ static void ilk_pipe_wm_get_hw_state(struct drm_crtc *crtc)
 		for (level = 0; level <= max_level; level++)
 			active->wm[level].enable = true;
 	}
+
+	intel_crtc->wm.active.ilk = *active;
 }
 
 #define _FW_WM(value, plane) \