[Intel-gfx] [PATCH v22 07/13] drm/i915: Use bw state for per crtc SAGV evaluation

[Stanislav Lisovskiy]

Future platforms require per-crtc SAGV evaluation
and serializing global state when those are changed
from different commits.

Signed-off-by: Stanislav Lisovskiy <stanislav.lisovskiy at intel.com>
Cc: Ville Syrjälä <ville.syrjala at intel.com>
Cc: James Ausmus <james.ausmus at intel.com>
---
 drivers/gpu/drm/i915/display/intel_bw.h |  6 +++
 drivers/gpu/drm/i915/intel_pm.c         | 63 +++++++++++++++++++------
 drivers/gpu/drm/i915/intel_pm.h         |  4 +-
 3 files changed, 58 insertions(+), 15 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_bw.h b/drivers/gpu/drm/i915/display/intel_bw.h
index ac004d6f4276..d6df91058223 100644
--- a/drivers/gpu/drm/i915/display/intel_bw.h
+++ b/drivers/gpu/drm/i915/display/intel_bw.h
@@ -18,6 +18,12 @@ struct intel_crtc_state;
 struct intel_bw_state {
 	struct intel_global_state base;
 
+	/*
+	 * Contains a bit mask, used to determine, whether correspondent
+	 * pipe allows SAGV or not.
+	 */
+	u8 pipe_sagv_reject;
+
 	unsigned int data_rate[I915_MAX_PIPES];
 	u8 num_active_planes[I915_MAX_PIPES];
 };
diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
index d1df288396d8..41305abad179 100644
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -43,6 +43,7 @@
 #include "i915_fixed.h"
 #include "i915_irq.h"
 #include "i915_trace.h"
+#include "display/intel_bw.h"
 #include "intel_pm.h"
 #include "intel_sideband.h"
 #include "../../../platform/x86/intel_ips.h"
@@ -3634,7 +3635,7 @@ static bool skl_needs_memory_bw_wa(struct drm_i915_private *dev_priv)
 	return IS_GEN9_BC(dev_priv) || IS_BROXTON(dev_priv);
 }
 
-static bool
+bool
 intel_has_sagv(struct drm_i915_private *dev_priv)
 {
 	/* HACK! */
@@ -3779,6 +3780,7 @@ void intel_sagv_post_plane_update(struct intel_atomic_state *state)
 
 static bool intel_crtc_can_enable_sagv(const struct intel_crtc_state *crtc_state)
 {
+	struct intel_atomic_state *state = to_intel_atomic_state(crtc_state->uapi.state);
 	struct drm_i915_private *dev_priv = to_i915(crtc_state->uapi.crtc->dev);
 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
 	struct intel_plane *plane;
@@ -3788,6 +3790,13 @@ static bool intel_crtc_can_enable_sagv(const struct intel_crtc_state *crtc_state
 	if (!crtc_state->hw.active)
 		return true;
 
+	/*
+	 * SKL+ workaround: bspec recommends we disable SAGV when we have
+	 * more then one pipe enabled
+	 */
+	if (hweight8(state->active_pipes) > 1)
+		return false;
+
 	if (crtc_state->hw.adjusted_mode.flags & DRM_MODE_FLAG_INTERLACE) {
 		DRM_DEBUG_KMS("No SAGV for interlaced mode on pipe %c\n",
 			      pipe_name(crtc->pipe));
@@ -3827,29 +3836,51 @@ static bool intel_crtc_can_enable_sagv(const struct intel_crtc_state *crtc_state
 }
 
 
-bool intel_can_enable_sagv(struct intel_atomic_state *state)
+bool intel_can_enable_sagv(const struct intel_bw_state *bw_state)
+{
+	return bw_state->pipe_sagv_reject == 0;
+}
+
+static int intel_compute_sagv_mask(struct intel_atomic_state *state)
 {
 	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
+	int ret;
 	struct intel_crtc *crtc;
 	const struct intel_crtc_state *crtc_state;
 	enum pipe pipe;
+	struct intel_crtc_state *new_crtc_state;
+	struct intel_bw_state *new_bw_state = NULL;
+	const struct intel_bw_state *old_bw_state = NULL;
+	int i;
 
 	if (!intel_has_sagv(dev_priv))
-		return false;
+		return 0;
 
-	/*
-	 * SKL+ workaround: bspec recommends we disable SAGV when we have
-	 * more then one pipe enabled
-	 */
-	if (hweight8(state->active_pipes) > 1)
-		return false;
+	for_each_new_intel_crtc_in_state(state, crtc,
+					 new_crtc_state, i) {
+
+		new_bw_state = intel_atomic_get_bw_state(state);
+		if (IS_ERR(new_bw_state))
+			return PTR_ERR(new_bw_state);
+
+		old_bw_state = intel_atomic_get_old_bw_state(state);
 
-	/* Since we're now guaranteed to only have one active CRTC... */
-	pipe = ffs(state->active_pipes) - 1;
-	crtc = intel_get_crtc_for_pipe(dev_priv, pipe);
-	crtc_state = to_intel_crtc_state(crtc->base.state);
+		if (intel_crtc_can_enable_sagv(new_crtc_state))
+			new_bw_state->pipe_sagv_reject &= ~BIT(crtc->pipe);
+		else
+			new_bw_state->pipe_sagv_reject |= BIT(crtc->pipe);
+	}
+
+	if (!old_bw_state)
+		return 0;
 
-	return intel_crtc_can_enable_sagv(crtc_state);
+	if (new_bw_state->pipe_sagv_reject != old_bw_state->pipe_sagv_reject) {
+		ret = intel_atomic_serialize_global_state(&new_bw_state->base);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
 }
 
 /*
@@ -5864,6 +5895,10 @@ skl_compute_wm(struct intel_atomic_state *state)
 	if (ret)
 		return ret;
 
+	ret = intel_compute_sagv_mask(state);
+	if (ret)
+		return ret;
+
 	/*
 	 * skl_compute_ddb() will have adjusted the final watermarks
 	 * based on how much ddb is available. Now we can actually
diff --git a/drivers/gpu/drm/i915/intel_pm.h b/drivers/gpu/drm/i915/intel_pm.h
index 9a6036ab0f90..abefc4205d0b 100644
--- a/drivers/gpu/drm/i915/intel_pm.h
+++ b/drivers/gpu/drm/i915/intel_pm.h
@@ -9,6 +9,7 @@
 #include <linux/types.h>
 
 #include "i915_reg.h"
+#include "display/intel_bw.h"
 
 struct drm_device;
 struct drm_i915_private;
@@ -41,7 +42,8 @@ void skl_pipe_wm_get_hw_state(struct intel_crtc *crtc,
 			      struct skl_pipe_wm *out);
 void g4x_wm_sanitize(struct drm_i915_private *dev_priv);
 void vlv_wm_sanitize(struct drm_i915_private *dev_priv);
-bool intel_can_enable_sagv(struct intel_atomic_state *state);
+bool intel_has_sagv(struct drm_i915_private *dev_priv);
+bool intel_can_enable_sagv(const struct intel_bw_state *bw_state);
 int intel_enable_sagv(struct drm_i915_private *dev_priv);
 int intel_disable_sagv(struct drm_i915_private *dev_priv);
 void intel_sagv_pre_plane_update(struct intel_atomic_state *state);
-- 
2.24.1.485.gad05a3d8e5