[PATCH v7 2/3] drm/i915/gen9+: Add support for pipe background color

[Matt Roper]

Gen9+ platforms allow CRTC's to be programmed with a background/canvas
color below the programmable planes.  Let's expose this for use by
compositors.

v2:
 - Split out bgcolor sanitization and programming of csc/gamma bits to a
   separate patch that we can land before the ABI changes are ready to
   go in.  (Ville)
 - Change a temporary variable name to be more consistent with
   other similar functions.  (Ville)
 - Change register name to SKL_CANVAS for consistency with the
   CHV_CANVAS register.

v3:
 - Switch register name back to SKL_BOTTOM_COLOR.  (Ville)
 - Use non-_FW register write.  (Ville)
 - Minor parameter rename for consistency.  (Ville)

v4:
 - Removed use of bgcolor_changed flag.

v5:
 - s/uint64_t/u64/

v6:
 - Rebase onto latest drm-tip (bgcolor writing now moves to the new
   color_commit function added by Ville's series)

v7:
 - Rebase

Cc: dri-devel at lists.freedesktop.org
Cc: wei.c.li at intel.com
Cc: harish.krupo.kps at intel.com
Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
Signed-off-by: Matt Roper <matthew.d.roper at intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/display/intel_color.c   | 11 ++++++++---
 drivers/gpu/drm/i915/display/intel_display.c | 13 +++++++++++++
 drivers/gpu/drm/i915/i915_debugfs.c          |  9 +++++++++
 3 files changed, 30 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_color.c b/drivers/gpu/drm/i915/display/intel_color.c
index 9ab34902663e..f93153ffc843 100644
--- a/drivers/gpu/drm/i915/display/intel_color.c
+++ b/drivers/gpu/drm/i915/display/intel_color.c
@@ -481,12 +481,17 @@ static void skl_color_commit(const struct intel_crtc_state *crtc_state)
 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->base.crtc);
 	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
 	enum pipe pipe = crtc->pipe;
+	u64 propval = crtc_state->base.bgcolor;
 	u32 val = 0;
 
+	/* Hardware is programmed with 10 bits of precision */
+	val = DRM_ARGB_RED(propval, 10) << 20
+	    | DRM_ARGB_GREEN(propval, 10) << 10
+	    | DRM_ARGB_BLUE(propval, 10);
+
 	/*
-	 * We don't (yet) allow userspace to control the pipe background color,
-	 * so force it to black, but apply pipe gamma and CSC appropriately
-	 * so that its handling will match how we program our planes.
+	 * Apply pipe gamma and CSC appropriately so that its handling will
+	 * match how we program our planes.
 	 */
 	if (crtc_state->gamma_enable)
 		val |= SKL_BOTTOM_COLOR_GAMMA_ENABLE;
diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index bbe088b9d057..78e64c62f34f 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -11833,8 +11833,12 @@ static int intel_crtc_atomic_check(struct drm_crtc *_crtc,
 {
 	struct intel_crtc *crtc = to_intel_crtc(_crtc);
 	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+	struct intel_atomic_state *state =
+		to_intel_atomic_state(_crtc_state->state);
 	struct intel_crtc_state *crtc_state =
 		to_intel_crtc_state(_crtc_state);
+	struct intel_crtc_state *old_crtc_state =
+		intel_atomic_get_old_crtc_state(state, crtc);
 	int ret;
 	bool mode_changed = needs_modeset(crtc_state);
 
@@ -11864,6 +11868,9 @@ static int intel_crtc_atomic_check(struct drm_crtc *_crtc,
 			return ret;
 	}
 
+	if (crtc_state->base.bgcolor != old_crtc_state->base.bgcolor)
+		crtc_state->base.color_mgmt_changed = true;
+
 	ret = 0;
 	if (dev_priv->display.compute_pipe_wm) {
 		ret = dev_priv->display.compute_pipe_wm(crtc_state);
@@ -15210,6 +15217,9 @@ static int intel_crtc_init(struct drm_i915_private *dev_priv, enum pipe pipe)
 
 	WARN_ON(drm_crtc_index(&intel_crtc->base) != intel_crtc->pipe);
 
+	if (INTEL_GEN(dev_priv) >= 9)
+		drm_crtc_add_bgcolor_property(&intel_crtc->base);
+
 	return 0;
 
 fail:
@@ -16495,6 +16505,9 @@ static void intel_sanitize_crtc(struct intel_crtc *crtc,
 	struct intel_crtc_state *crtc_state = to_intel_crtc_state(crtc->base.state);
 	enum transcoder cpu_transcoder = crtc_state->cpu_transcoder;
 
+	/* Always force bgcolor to solid black */
+	crtc_state->base.bgcolor = drm_argb(16, 0xFFFF, 0, 0, 0);
+
 	/* Clear any frame start delays used for debugging left by the BIOS */
 	if (crtc->active && !transcoder_is_dsi(cpu_transcoder)) {
 		i915_reg_t reg = PIPECONF(cpu_transcoder);
diff --git a/drivers/gpu/drm/i915/i915_debugfs.c b/drivers/gpu/drm/i915/i915_debugfs.c
index fec9fb7cc384..ccb08b759b89 100644
--- a/drivers/gpu/drm/i915/i915_debugfs.c
+++ b/drivers/gpu/drm/i915/i915_debugfs.c
@@ -2773,6 +2773,15 @@ static int i915_display_info(struct seq_file *m, void *unused)
 			intel_plane_info(m, crtc);
 		}
 
+		if (INTEL_GEN(dev_priv) >= 9 && pipe_config->base.active) {
+			u64 background = pipe_config->base.bgcolor;
+
+			seq_printf(m, "\tbackground color (10bpc): r=%x g=%x b=%x\n",
+				   DRM_ARGB_RED(background, 10),
+				   DRM_ARGB_GREEN(background, 10),
+				   DRM_ARGB_BLUE(background, 10));
+		}
+
 		seq_printf(m, "\tunderrun reporting: cpu=%s pch=%s \n",
 			   yesno(!crtc->cpu_fifo_underrun_disabled),
 			   yesno(!crtc->pch_fifo_underrun_disabled));
-- 
2.21.0