[Intel-gfx] [v8][PATCH 01/10] drm/i915/display: Add func to get gamma bit precision

[Shankar, Uma]

>-----Original Message-----
>From: Sharma, Swati2
>Sent: Monday, August 26, 2019 11:56 AM
>To: intel-gfx at lists.freedesktop.org
>Cc: Nikula, Jani <jani.nikula at intel.com>; Sharma, Shashank
><shashank.sharma at intel.com>; Manna, Animesh <animesh.manna at intel.com>;
>Nautiyal, Ankit K <ankit.k.nautiyal at intel.com>; daniel.vetter at ffwll.ch;
>ville.syrjala at linux.intel.com; Shankar, Uma <uma.shankar at intel.com>; Sharma,
>Swati2 <swati2.sharma at intel.com>
>Subject: [v8][PATCH 01/10] drm/i915/display: Add func to get gamma bit precision
>
>Each platform supports different gamma modes and each gamma mode has different
>bit precision. Add func/platform to get bit precision corresponding to gamma mode.

I think it would be good to add some explanation as to why this is needed.
Also what all platforms are supported by this currently. 

>Signed-off-by: Swati Sharma <swati2.sharma at intel.com>
>---
> drivers/gpu/drm/i915/display/intel_color.c | 79 ++++++++++++++++++++++++++++++
>drivers/gpu/drm/i915/display/intel_color.h |  1 +
> 2 files changed, 80 insertions(+)
>
>diff --git a/drivers/gpu/drm/i915/display/intel_color.c
>b/drivers/gpu/drm/i915/display/intel_color.c
>index 71a0201..d2c1297 100644
>--- a/drivers/gpu/drm/i915/display/intel_color.c
>+++ b/drivers/gpu/drm/i915/display/intel_color.c
>@@ -1371,6 +1371,85 @@ static int icl_color_check(struct intel_crtc_state
>*crtc_state)
> 	return 0;
> }
>
>+static int i9xx_gamma_precision(const struct intel_crtc_state
>+*crtc_state) {
>+	if (!crtc_state->gamma_enable)
>+		return 0;
>+
>+	switch (crtc_state->gamma_mode) {
>+	case GAMMA_MODE_MODE_8BIT:
>+		return 8;
>+	case GAMMA_MODE_MODE_10BIT:
>+		return 16;
>+	default:
>+		MISSING_CASE(crtc_state->gamma_mode);
>+		return 0;
>+	}
>+}
>+
>+static int chv_gamma_precision(const struct intel_crtc_state
>+*crtc_state) {
>+	if (crtc_state->cgm_mode & CGM_PIPE_MODE_GAMMA)
>+		return 10;
>+	else
>+		return i9xx_gamma_precision(crtc_state); }
>+
>+static int glk_gamma_precision(const struct intel_crtc_state
>+*crtc_state) {
>+	if (!crtc_state->gamma_enable)
>+		return 0;
>+
>+	switch (crtc_state->gamma_mode) {
>+	case GAMMA_MODE_MODE_8BIT:
>+		return 8;
>+	case GAMMA_MODE_MODE_10BIT:
>+		return 10;
>+	default:
>+		MISSING_CASE(crtc_state->gamma_mode);
>+		return 0;
>+	}
>+}
>+
>+static int ilk_gamma_precision(const struct intel_crtc_state
>+*crtc_state) {
>+	if (!crtc_state->gamma_enable)
>+		return 0;
>+
>+	if ((crtc_state->csc_mode & CSC_POSITION_BEFORE_GAMMA) == 0)
>+		return 0;
>+
>+	switch (crtc_state->gamma_mode) {
>+	case GAMMA_MODE_MODE_8BIT:
>+		return 8;
>+	case GAMMA_MODE_MODE_10BIT:
>+		return 10;
>+	default:
>+		MISSING_CASE(crtc_state->gamma_mode);
>+		return 0;
>+	}
>+}
>+
>+int intel_color_get_gamma_bit_precision(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);
>+
>+	if (HAS_GMCH(dev_priv)) {
>+		if (IS_CHERRYVIEW(dev_priv))
>+			return chv_gamma_precision(crtc_state);
>+		else
>+			return i9xx_gamma_precision(crtc_state);
>+	} else {
>+		if (IS_CANNONLAKE(dev_priv) || IS_GEMINILAKE(dev_priv))
>+			return glk_gamma_precision(crtc_state);
>+		else if (IS_IRONLAKE(dev_priv))
>+			return ilk_gamma_precision(crtc_state);
>+	}
>+
>+	return 0;
>+}
>+
> void intel_color_init(struct intel_crtc *crtc)  {
> 	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev); diff --git
>a/drivers/gpu/drm/i915/display/intel_color.h
>b/drivers/gpu/drm/i915/display/intel_color.h
>index 057e8ac..0226d3a 100644
>--- a/drivers/gpu/drm/i915/display/intel_color.h
>+++ b/drivers/gpu/drm/i915/display/intel_color.h
>@@ -14,5 +14,6 @@
> void intel_color_commit(const struct intel_crtc_state *crtc_state);  void
>intel_color_load_luts(const struct intel_crtc_state *crtc_state);  void
>intel_color_get_config(struct intel_crtc_state *crtc_state);
>+int intel_color_get_gamma_bit_precision(const struct intel_crtc_state
>+*crtc_state);
>
> #endif /* __INTEL_COLOR_H__ */
>--
>1.9.1