[SRU][B/OEM-B][PATCH v2 2/4] drm/i915: Save the old CDCLK atomic state

[Hui Wang]

From: Imre Deak <imre.deak at intel.com>

BugLink: https://launchpad.net/bugs/1826868

The old state will be needed by an upcoming patch to determine if the
commit increases or decreases CDCLK, so move the old state to the atomic
state (while keeping the new one in dev_priv). cdclk.logical and
cdclk.actual in the atomic state isn't used atm anywhere after the
atomic check phase, so this should be safe.

v2:
- Use swap() instead of opencoding it. (Ville)

Suggested-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
Signed-off-by: Imre Deak <imre.deak at intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190320135439.12201-2-imre.deak@intel.com
(backported from commit 48d9f87ddd2108663fd866b254e05d422243cc56)
Signed-off-by: Hui Wang <hui.wang at canonical.com>
---
 drivers/gpu/drm/i915/intel_cdclk.c   | 20 ++++++++++++++++++++
 drivers/gpu/drm/i915/intel_display.c |  4 ++--
 drivers/gpu/drm/i915/intel_drv.h     |  1 +
 3 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/i915/intel_cdclk.c b/drivers/gpu/drm/i915/intel_cdclk.c
index cb23023d9da1..fd41b7296990 100644
--- a/drivers/gpu/drm/i915/intel_cdclk.c
+++ b/drivers/gpu/drm/i915/intel_cdclk.c
@@ -1732,6 +1732,26 @@ bool intel_cdclk_state_compare(const struct intel_cdclk_state *a,
 	return memcmp(a, b, sizeof(*a)) == 0;
 }
 
+/**
+ * intel_cdclk_swap_state - make atomic CDCLK configuration effective
+ * @state: atomic state
+ *
+ * This is the CDCLK version of drm_atomic_helper_swap_state() since the
+ * helper does not handle driver-specific global state.
+ *
+ * Similarly to the atomic helpers this function does a complete swap,
+ * i.e. it also puts the old state into @state. This is used by the commit
+ * code to determine how CDCLK has changed (for instance did it increase or
+ * decrease).
+ */
+void intel_cdclk_swap_state(struct intel_atomic_state *state)
+{
+	struct drm_i915_private *dev_priv = to_i915(state->base.dev);
+
+	swap(state->cdclk.logical, dev_priv->cdclk.logical);
+	swap(state->cdclk.actual, dev_priv->cdclk.actual);
+}
+
 /**
  * intel_set_cdclk - Push the CDCLK state to the hardware
  * @dev_priv: i915 device
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index b474d2d3e9ba..3294c13f8b8a 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -12549,10 +12549,10 @@ static int intel_atomic_commit(struct drm_device *dev,
 		memcpy(dev_priv->min_cdclk, intel_state->min_cdclk,
 		       sizeof(intel_state->min_cdclk));
 		dev_priv->active_crtcs = intel_state->active_crtcs;
-		dev_priv->cdclk.logical = intel_state->cdclk.logical;
-		dev_priv->cdclk.actual = intel_state->cdclk.actual;
 		dev_priv->cdclk.force_min_cdclk =
 			intel_state->cdclk.force_min_cdclk;
+
+		intel_cdclk_swap_state(intel_state);
 	}
 
 	drm_atomic_state_get(state);
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index db287fbe9abc..83d3724197bd 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1326,6 +1326,7 @@ void intel_update_cdclk(struct drm_i915_private *dev_priv);
 void intel_update_rawclk(struct drm_i915_private *dev_priv);
 bool intel_cdclk_state_compare(const struct intel_cdclk_state *a,
 			       const struct intel_cdclk_state *b);
+void intel_cdclk_swap_state(struct intel_atomic_state *state);
 void intel_set_cdclk(struct drm_i915_private *dev_priv,
 		     const struct intel_cdclk_state *cdclk_state);
 
-- 
2.17.1