drm/i915: Track pipe gamma enable/disable in crtc state

Track whether pipe gamma is enabled or disabled. For now we
stick to the current behaviour of always enabling gamma. But
we do get working state readout for this now. On SKL+ we use
the pipe bottom color as our hardware state. On pre-SKL we
read the state back from the primary plane control register.
That only really correct for g4x+, as older platforms never
gamma correct pipe bottom color. But doing the readout the
same way on all platforms is fine, and there is no other way
to do it really.

v2: Initialize val at declaration (Uma)
    Drop the bogus skl scaler comment change (Uma)
    Rebase
v3: Allow fastboot with gamma_enable changes (Maarten)
v4: Drop the PIPE_BOTTOM_COLOR write from
    intel_update_pipe_config() again. It snuck back in
    during the rebase
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Reviewed-by: Uma Shankar <uma.shankar@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190207203913.5529-1-ville.syrjala@linux.intel.com

drivers/gpu/drm/i915/intel_color.c

@@ -387,6 +387,28 @@ static void hsw_color_commit(const struct intel_crtc_state *crtc_state)
 	ilk_load_csc_matrix(crtc_state);
 }
 
+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;
+	u32 val = 0;
+
+	/*
+	 * 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.
+	 */
+	if (crtc_state->gamma_enable)
+		val |= SKL_BOTTOM_COLOR_GAMMA_ENABLE;
+	val |= SKL_BOTTOM_COLOR_CSC_ENABLE;
+	I915_WRITE(SKL_BOTTOM_COLOR(pipe), val);
+
+	I915_WRITE(GAMMA_MODE(crtc->pipe), crtc_state->gamma_mode);
+
+	ilk_load_csc_matrix(crtc_state);
+}
+
 static void bdw_load_degamma_lut(const struct intel_crtc_state *crtc_state)
 {
 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->base.crtc);
@@ -644,6 +666,8 @@ int intel_color_check(struct intel_crtc_state *crtc_state)
 	degamma_tests = INTEL_INFO(dev_priv)->color.degamma_lut_tests;
 	gamma_tests = INTEL_INFO(dev_priv)->color.gamma_lut_tests;
 
+	crtc_state->gamma_enable = true;
+
 	/* Always allow legacy gamma LUT with no further checking. */
 	if (crtc_state_is_legacy_gamma(crtc_state)) {
 		crtc_state->gamma_mode = GAMMA_MODE_MODE_8BIT;
@@ -689,7 +713,9 @@ void intel_color_init(struct intel_crtc *crtc)
 		else
 			dev_priv->display.load_luts = i9xx_load_luts;
 
-		if (INTEL_GEN(dev_priv) >= 8 || IS_HASWELL(dev_priv))
+		if (INTEL_GEN(dev_priv) >= 9)
+			dev_priv->display.color_commit = skl_color_commit;
+		else if (IS_BROADWELL(dev_priv) || IS_HASWELL(dev_priv))
 			dev_priv->display.color_commit = hsw_color_commit;
 		else
 			dev_priv->display.color_commit = ilk_color_commit;

drivers/gpu/drm/i915/intel_display.c

@@ -3221,7 +3221,8 @@ static u32 i9xx_plane_ctl_crtc(const struct intel_crtc_state *crtc_state)
 	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
 	u32 dspcntr = 0;
 
-	dspcntr |= DISPPLANE_GAMMA_ENABLE;
+	if (crtc_state->gamma_enable)
+		dspcntr |= DISPPLANE_GAMMA_ENABLE;
 
 	if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv))
 		dspcntr |= DISPPLANE_PIPE_CSC_ENABLE;
@@ -3701,7 +3702,9 @@ u32 skl_plane_ctl_crtc(const struct intel_crtc_state *crtc_state)
 	if (INTEL_GEN(dev_priv) >= 10 || IS_GEMINILAKE(dev_priv))
 		return plane_ctl;
 
-	plane_ctl |= PLANE_CTL_PIPE_GAMMA_ENABLE;
+	if (crtc_state->gamma_enable)
+		plane_ctl |= PLANE_CTL_PIPE_GAMMA_ENABLE;
+
 	plane_ctl |= PLANE_CTL_PIPE_CSC_ENABLE;
 
 	return plane_ctl;
@@ -3754,7 +3757,9 @@ u32 glk_plane_color_ctl_crtc(const struct intel_crtc_state *crtc_state)
 	if (INTEL_GEN(dev_priv) >= 11)
 		return plane_color_ctl;
 
-	plane_color_ctl |= PLANE_COLOR_PIPE_GAMMA_ENABLE;
+	if (crtc_state->gamma_enable)
+		plane_color_ctl |= PLANE_COLOR_PIPE_GAMMA_ENABLE;
+
 	plane_color_ctl |= PLANE_COLOR_PIPE_CSC_ENABLE;
 
 	return plane_color_ctl;
@@ -3999,16 +4004,6 @@ static void intel_update_pipe_config(const struct intel_crtc_state *old_crtc_sta
 			ironlake_pfit_disable(old_crtc_state);
 	}
 
-	/*
-	 * We don't (yet) allow userspace to control the pipe background color,
-	 * so force it to black, but apply pipe gamma and CSC so that its
-	 * handling will match how we program our planes.
-	 */
-	if (INTEL_GEN(dev_priv) >= 9)
-		I915_WRITE(SKL_BOTTOM_COLOR(crtc->pipe),
-			   SKL_BOTTOM_COLOR_GAMMA_ENABLE |
-			   SKL_BOTTOM_COLOR_CSC_ENABLE);
-
 	if (INTEL_GEN(dev_priv) >= 11)
 		icl_set_pipe_chicken(crtc);
 }
@@ -8101,6 +8096,20 @@ static void intel_get_crtc_ycbcr_config(struct intel_crtc *crtc,
 	pipe_config->output_format = output;
 }
 
+static void i9xx_get_pipe_color_config(struct intel_crtc_state *crtc_state)
+{
+	struct intel_crtc *crtc = to_intel_crtc(crtc_state->base.crtc);
+	struct intel_plane *plane = to_intel_plane(crtc->base.primary);
+	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+	enum i9xx_plane_id i9xx_plane = plane->i9xx_plane;
+	u32 tmp;
+
+	tmp = I915_READ(DSPCNTR(i9xx_plane));
+
+	if (tmp & DISPPLANE_GAMMA_ENABLE)
+		crtc_state->gamma_enable = true;
+}
+
 static bool i9xx_get_pipe_config(struct intel_crtc *crtc,
 				 struct intel_crtc_state *pipe_config)
 {
@@ -8149,6 +8158,8 @@ static bool i9xx_get_pipe_config(struct intel_crtc *crtc,
 	pipe_config->gamma_mode = (tmp & PIPECONF_GAMMA_MODE_MASK_I9XX) >>
 		PIPECONF_GAMMA_MODE_SHIFT;
 
+	i9xx_get_pipe_color_config(pipe_config);
+
 	if (INTEL_GEN(dev_priv) < 4)
 		pipe_config->double_wide = tmp & PIPECONF_DOUBLE_WIDE;
 
@@ -9227,6 +9238,8 @@ static bool ironlake_get_pipe_config(struct intel_crtc *crtc,
 	pipe_config->gamma_mode = (tmp & PIPECONF_GAMMA_MODE_MASK_ILK) >>
 		PIPECONF_GAMMA_MODE_SHIFT;
 
+	i9xx_get_pipe_color_config(pipe_config);
+
 	if (I915_READ(PCH_TRANSCONF(crtc->pipe)) & TRANS_ENABLE) {
 		struct intel_shared_dpll *pll;
 		enum intel_dpll_id pll_id;
@@ -9861,6 +9874,15 @@ static bool haswell_get_pipe_config(struct intel_crtc *crtc,
 	pipe_config->gamma_mode =
 		I915_READ(GAMMA_MODE(crtc->pipe)) & GAMMA_MODE_MODE_MASK;
 
+	if (INTEL_GEN(dev_priv) >= 9) {
+		u32 tmp = I915_READ(SKL_BOTTOM_COLOR(crtc->pipe));
+
+		if (tmp & SKL_BOTTOM_COLOR_GAMMA_ENABLE)
+			pipe_config->gamma_enable = true;
+	} else {
+		i9xx_get_pipe_color_config(pipe_config);
+	}
+
 	power_domain = POWER_DOMAIN_PIPE_PANEL_FITTER(crtc->pipe);
 	if (intel_display_power_get_if_enabled(dev_priv, power_domain)) {
 		WARN_ON(power_domain_mask & BIT_ULL(power_domain));
@@ -10031,7 +10053,12 @@ i845_cursor_max_stride(struct intel_plane *plane,
 
 static u32 i845_cursor_ctl_crtc(const struct intel_crtc_state *crtc_state)
 {
-	return CURSOR_GAMMA_ENABLE;
+	u32 cntl = 0;
+
+	if (crtc_state->gamma_enable)
+		cntl |= CURSOR_GAMMA_ENABLE;
+
+	return cntl;
 }
 
 static u32 i845_cursor_ctl(const struct intel_crtc_state *crtc_state,
@@ -10185,7 +10212,8 @@ static u32 i9xx_cursor_ctl_crtc(const struct intel_crtc_state *crtc_state)
 	if (INTEL_GEN(dev_priv) >= 11)
 		return cntl;
 
-	cntl |= MCURSOR_GAMMA_ENABLE;
+	if (crtc_state->gamma_enable)
+		cntl = MCURSOR_GAMMA_ENABLE;
 
 	if (HAS_DDI(dev_priv))
 		cntl |= MCURSOR_PIPE_CSC_ENABLE;
@@ -11180,12 +11208,6 @@ static int intel_crtc_atomic_check(struct drm_crtc *crtc,
 		ret = intel_color_check(pipe_config);
 		if (ret)
 			return ret;
-
-		/*
-		 * Changing color management on Intel hardware is
-		 * handled as part of planes update.
-		 */
-		crtc_state->planes_changed = true;
 	}
 
 	ret = 0;
@@ -12092,6 +12114,7 @@ intel_pipe_config_compare(struct drm_i915_private *dev_priv,
 		PIPE_CONF_CHECK_CLOCK_FUZZY(pixel_rate);
 
 		PIPE_CONF_CHECK_X(gamma_mode);
+		PIPE_CONF_CHECK_BOOL(gamma_enable);
 	}
 
 	PIPE_CONF_CHECK_BOOL(double_wide);

drivers/gpu/drm/i915/intel_drv.h

@@ -960,6 +960,9 @@ struct intel_crtc_state {
 	/* Output down scaling is done in LSPCON device */
 	bool lspcon_downsampling;
 
+	/* enable pipe gamma? */
+	bool gamma_enable;
+
 	/* Display Stream compression state */
 	struct {
 		bool compression_enable;

drivers/gpu/drm/i915/intel_sprite.c

@@ -741,7 +741,12 @@ vlv_update_clrc(const struct intel_plane_state *plane_state)
 
 static u32 vlv_sprite_ctl_crtc(const struct intel_crtc_state *crtc_state)
 {
-	return SP_GAMMA_ENABLE;
+	u32 sprctl = 0;
+
+	if (crtc_state->gamma_enable)
+		sprctl |= SP_GAMMA_ENABLE;
+
+	return sprctl;
 }
 
 static u32 vlv_sprite_ctl(const struct intel_crtc_state *crtc_state,
@@ -919,7 +924,8 @@ static u32 ivb_sprite_ctl_crtc(const struct intel_crtc_state *crtc_state)
 	struct drm_i915_private *dev_priv = to_i915(crtc_state->base.crtc->dev);
 	u32 sprctl = 0;
 
-	sprctl |= SPRITE_GAMMA_ENABLE;
+	if (crtc_state->gamma_enable)
+		sprctl |= SPRITE_GAMMA_ENABLE;
 
 	if (IS_HASWELL(dev_priv) || IS_BROADWELL(dev_priv))
 		sprctl |= SPRITE_PIPE_CSC_ENABLE;
@@ -1107,7 +1113,12 @@ g4x_sprite_max_stride(struct intel_plane *plane,
 
 static u32 g4x_sprite_ctl_crtc(const struct intel_crtc_state *crtc_state)
 {
-	return DVS_GAMMA_ENABLE;
+	u32 dvscntr = 0;
+
+	if (crtc_state->gamma_enable)
+		dvscntr |= DVS_GAMMA_ENABLE;
+
+	return dvscntr;
 }
 
 static u32 g4x_sprite_ctl(const struct intel_crtc_state *crtc_state,