drm/i915: Populate gamma_mode for all platforms

On pre-HSW gamma mode is configured via PIPECONF. The bits are
the same except shifted up, so we can reuse just store them in
crtc_state->gamma_mode in the HSW+ way, allowing us to share
some code later.

v2: Allow fastboot with gamma_mode changes (Maarten)
    Add space around the '<<' in the reg macro
    Deal with HAS_GMCH
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Maarten Lankhorst <maarten.lankhorst@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190207202146.26423-2-ville.syrjala@linux.intel.com

drivers/gpu/drm/i915/i915_reg.h

@@ -5590,9 +5590,15 @@ enum {
 #define   PIPECONF_SINGLE_WIDE	0
 #define   PIPECONF_PIPE_UNLOCKED 0
 #define   PIPECONF_PIPE_LOCKED	(1 << 25)
-#define   PIPECONF_PALETTE	0
-#define   PIPECONF_GAMMA		(1 << 24)
 #define   PIPECONF_FORCE_BORDER	(1 << 25)
+#define   PIPECONF_GAMMA_MODE_MASK_I9XX	(1 << 24) /* gmch */
+#define   PIPECONF_GAMMA_MODE_MASK_ILK	(3 << 24) /* ilk-ivb */
+#define   PIPECONF_GAMMA_MODE_8BIT	(0 << 24) /* gmch,ilk-ivb */
+#define   PIPECONF_GAMMA_MODE_10BIT	(1 << 24) /* gmch,ilk-ivb */
+#define   PIPECONF_GAMMA_MODE_12BIT	(2 << 24) /* ilk-ivb */
+#define   PIPECONF_GAMMA_MODE_SPLIT	(3 << 24) /* ivb */
+#define   PIPECONF_GAMMA_MODE(x)	((x) << 24) /* pass in GAMMA_MODE_MODE_* */
+#define   PIPECONF_GAMMA_MODE_SHIFT	24
 #define   PIPECONF_INTERLACE_MASK	(7 << 21)
 #define   PIPECONF_INTERLACE_MASK_HSW	(3 << 21)
 /* Note that pre-gen3 does not support interlaced display directly. Panel

drivers/gpu/drm/i915/intel_color.c

@@ -351,6 +351,32 @@ static void i9xx_load_luts(const struct intel_crtc_state *crtc_state)
 	i9xx_load_luts_internal(crtc_state, crtc_state->base.gamma_lut);
 }
 
+static void i9xx_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;
+	u32 val;
+
+	val = I915_READ(PIPECONF(pipe));
+	val &= ~PIPECONF_GAMMA_MODE_MASK_I9XX;
+	val |= PIPECONF_GAMMA_MODE(crtc_state->gamma_mode);
+	I915_WRITE(PIPECONF(pipe), val);
+}
+
+static void ilk_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;
+	u32 val;
+
+	val = I915_READ(PIPECONF(pipe));
+	val &= ~PIPECONF_GAMMA_MODE_MASK_ILK;
+	val |= PIPECONF_GAMMA_MODE(crtc_state->gamma_mode);
+	I915_WRITE(PIPECONF(pipe), val);
+}
+
 static void hsw_color_commit(const struct intel_crtc_state *crtc_state)
 {
 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->base.crtc);
@@ -585,8 +611,7 @@ void intel_color_commit(const struct intel_crtc_state *crtc_state)
 {
 	struct drm_i915_private *dev_priv = to_i915(crtc_state->base.crtc->dev);
 
-	if (dev_priv->display.color_commit)
-		dev_priv->display.color_commit(crtc_state);
+	dev_priv->display.color_commit(crtc_state);
 }
 
 static int check_lut_size(const struct drm_property_blob *lut, int expected)
@@ -649,20 +674,25 @@ void intel_color_init(struct intel_crtc *crtc)
 
 	drm_mode_crtc_set_gamma_size(&crtc->base, 256);
 
-	if (IS_CHERRYVIEW(dev_priv)) {
-		dev_priv->display.load_luts = cherryview_load_luts;
-	} else if (IS_HASWELL(dev_priv)) {
-		dev_priv->display.load_luts = i9xx_load_luts;
-		dev_priv->display.color_commit = hsw_color_commit;
-	} else if (IS_BROADWELL(dev_priv) || IS_GEN9_BC(dev_priv) ||
-		   IS_BROXTON(dev_priv)) {
-		dev_priv->display.load_luts = broadwell_load_luts;
-		dev_priv->display.color_commit = hsw_color_commit;
-	} else if (IS_GEMINILAKE(dev_priv) || IS_CANNONLAKE(dev_priv)) {
-		dev_priv->display.load_luts = glk_load_luts;
-		dev_priv->display.color_commit = hsw_color_commit;
+	if (HAS_GMCH(dev_priv)) {
+		if (IS_CHERRYVIEW(dev_priv))
+			dev_priv->display.load_luts = cherryview_load_luts;
+		else
+			dev_priv->display.load_luts = i9xx_load_luts;
+
+		dev_priv->display.color_commit = i9xx_color_commit;
 	} else {
-		dev_priv->display.load_luts = i9xx_load_luts;
+		if (IS_CANNONLAKE(dev_priv) || IS_GEMINILAKE(dev_priv))
+			dev_priv->display.load_luts = glk_load_luts;
+		else if (INTEL_GEN(dev_priv) >= 9 || IS_BROADWELL(dev_priv))
+			dev_priv->display.load_luts = broadwell_load_luts;
+		else
+			dev_priv->display.load_luts = i9xx_load_luts;
+
+		if (INTEL_GEN(dev_priv) >= 8 || IS_HASWELL(dev_priv))
+			dev_priv->display.color_commit = hsw_color_commit;
+		else
+			dev_priv->display.color_commit = ilk_color_commit;
 	}
 
 	/* Enable color management support when we have degamma & gamma LUTs. */

drivers/gpu/drm/i915/intel_display.c

@@ -3450,7 +3450,7 @@ static void i9xx_disable_plane(struct intel_plane *plane,
 	 *
 	 * On pre-g4x there is no way to gamma correct the
 	 * pipe bottom color but we'll keep on doing this
-	 * anyway.
+	 * anyway so that the crtc state readout works correctly.
 	 */
 	dspcntr = i9xx_plane_ctl_crtc(crtc_state);
 
@@ -7692,6 +7692,8 @@ static void i9xx_set_pipeconf(const struct intel_crtc_state *crtc_state)
 	     crtc_state->limited_color_range)
 		pipeconf |= PIPECONF_COLOR_RANGE_SELECT;
 
+	pipeconf |= PIPECONF_GAMMA_MODE(crtc_state->gamma_mode);
+
 	I915_WRITE(PIPECONF(crtc->pipe), pipeconf);
 	POSTING_READ(PIPECONF(crtc->pipe));
 }
@@ -8144,6 +8146,9 @@ static bool i9xx_get_pipe_config(struct intel_crtc *crtc,
 	    (tmp & PIPECONF_COLOR_RANGE_SELECT))
 		pipe_config->limited_color_range = true;
 
+	pipe_config->gamma_mode = (tmp & PIPECONF_GAMMA_MODE_MASK_I9XX) >>
+		PIPECONF_GAMMA_MODE_SHIFT;
+
 	if (INTEL_GEN(dev_priv) < 4)
 		pipe_config->double_wide = tmp & PIPECONF_DOUBLE_WIDE;
 
@@ -8683,6 +8688,8 @@ static void ironlake_set_pipeconf(const struct intel_crtc_state *crtc_state)
 	if (crtc_state->limited_color_range)
 		val |= PIPECONF_COLOR_RANGE_SELECT;
 
+	val |= PIPECONF_GAMMA_MODE(crtc_state->gamma_mode);
+
 	I915_WRITE(PIPECONF(pipe), val);
 	POSTING_READ(PIPECONF(pipe));
 }
@@ -9217,6 +9224,9 @@ static bool ironlake_get_pipe_config(struct intel_crtc *crtc,
 	if (tmp & PIPECONF_COLOR_RANGE_SELECT)
 		pipe_config->limited_color_range = true;
 
+	pipe_config->gamma_mode = (tmp & PIPECONF_GAMMA_MODE_MASK_ILK) >>
+		PIPECONF_GAMMA_MODE_SHIFT;
+
 	if (I915_READ(PCH_TRANSCONF(crtc->pipe)) & TRANS_ENABLE) {
 		struct intel_shared_dpll *pll;
 		enum intel_dpll_id pll_id;
@@ -12080,6 +12090,8 @@ intel_pipe_config_compare(struct drm_i915_private *dev_priv,
 
 		PIPE_CONF_CHECK_I(scaler_state.scaler_id);
 		PIPE_CONF_CHECK_CLOCK_FUZZY(pixel_rate);
+
+		PIPE_CONF_CHECK_X(gamma_mode);
 	}
 
 	PIPE_CONF_CHECK_BOOL(double_wide);