drm/i915/dsb: Enable gamma lut programming using DSB.

Gamma lut programming can be programmed using DSB
where bulk register programming can be done using indexed
register write which takes number of data and the mmio offset
to be written.

Currently enabled for 12-bit gamma LUT which is enabled by
default and later 8-bit/10-bit will be enabled in future
based on need.

v1: Initial version.
v2: Directly call dsb-api at callsites. (Jani)
v3:
- modified the code as per single dsb instance per crtc. (Shashank)
- Added dsb get/put call in platform specific load_lut hook. (Jani)
- removed dsb pointer from dev_priv. (Jani)
v4: simplified code by dropping ref-count implementation. (Shashank)

Cc: Jani Nikula <jani.nikula@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: Animesh Manna <animesh.manna@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20190920115930.27829-9-animesh.manna@intel.com

drivers/gpu/drm/i915/display/intel_color.c

@@ -627,12 +627,13 @@ static void bdw_load_lut_10(struct intel_crtc *crtc,
 static void ivb_load_lut_ext_max(struct intel_crtc *crtc)
 {
 	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+	struct intel_dsb *dsb = intel_dsb_get(crtc);
 	enum pipe pipe = crtc->pipe;
 
 	/* Program the max register to clamp values > 1.0. */
-	I915_WRITE(PREC_PAL_EXT_GC_MAX(pipe, 0), 1 << 16);
-	I915_WRITE(PREC_PAL_EXT_GC_MAX(pipe, 1), 1 << 16);
-	I915_WRITE(PREC_PAL_EXT_GC_MAX(pipe, 2), 1 << 16);
+	intel_dsb_reg_write(dsb, PREC_PAL_EXT_GC_MAX(pipe, 0), 1 << 16);
+	intel_dsb_reg_write(dsb, PREC_PAL_EXT_GC_MAX(pipe, 1), 1 << 16);
+	intel_dsb_reg_write(dsb, PREC_PAL_EXT_GC_MAX(pipe, 2), 1 << 16);
 
 	/*
 	 * Program the gc max 2 register to clamp values > 1.0.
@@ -640,10 +641,15 @@ static void ivb_load_lut_ext_max(struct intel_crtc *crtc)
 	 * from 3.0 to 7.0
 	 */
 	if (INTEL_GEN(dev_priv) >= 10 || IS_GEMINILAKE(dev_priv)) {
-		I915_WRITE(PREC_PAL_EXT2_GC_MAX(pipe, 0), 1 << 16);
-		I915_WRITE(PREC_PAL_EXT2_GC_MAX(pipe, 1), 1 << 16);
-		I915_WRITE(PREC_PAL_EXT2_GC_MAX(pipe, 2), 1 << 16);
+		intel_dsb_reg_write(dsb, PREC_PAL_EXT2_GC_MAX(pipe, 0),
+				    1 << 16);
+		intel_dsb_reg_write(dsb, PREC_PAL_EXT2_GC_MAX(pipe, 1),
+				    1 << 16);
+		intel_dsb_reg_write(dsb, PREC_PAL_EXT2_GC_MAX(pipe, 2),
+				    1 << 16);
 	}
+
+	intel_dsb_put(dsb);
 }
 
 static void ivb_load_luts(const struct intel_crtc_state *crtc_state)
@@ -803,22 +809,23 @@ icl_load_gcmax(const struct intel_crtc_state *crtc_state,
 	       const struct drm_color_lut *color)
 {
 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->base.crtc);
-	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
+	struct intel_dsb *dsb = intel_dsb_get(crtc);
 	enum pipe pipe = crtc->pipe;
 
 	/* Fixme: LUT entries are 16 bit only, so we can prog 0xFFFF max */
-	I915_WRITE(PREC_PAL_GC_MAX(pipe, 0), color->red);
-	I915_WRITE(PREC_PAL_GC_MAX(pipe, 1), color->green);
-	I915_WRITE(PREC_PAL_GC_MAX(pipe, 2), color->blue);
+	intel_dsb_reg_write(dsb, PREC_PAL_GC_MAX(pipe, 0), color->red);
+	intel_dsb_reg_write(dsb, PREC_PAL_GC_MAX(pipe, 1), color->green);
+	intel_dsb_reg_write(dsb, PREC_PAL_GC_MAX(pipe, 2), color->blue);
+	intel_dsb_put(dsb);
 }
 
 static void
 icl_program_gamma_superfine_segment(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);
 	const struct drm_property_blob *blob = crtc_state->base.gamma_lut;
 	const struct drm_color_lut *lut = blob->data;
+	struct intel_dsb *dsb = intel_dsb_get(crtc);
 	enum pipe pipe = crtc->pipe;
 	u32 i;
 
@@ -829,26 +836,29 @@ icl_program_gamma_superfine_segment(const struct intel_crtc_state *crtc_state)
 	 * 9 entries, corresponding to values 0, 1/(8 * 128 * 256),
 	 * 2/(8 * 128 * 256) ... 8/(8 * 128 * 256).
 	 */
-	I915_WRITE(PREC_PAL_MULTI_SEG_INDEX(pipe), PAL_PREC_AUTO_INCREMENT);
+	intel_dsb_reg_write(dsb, PREC_PAL_MULTI_SEG_INDEX(pipe),
+			    PAL_PREC_AUTO_INCREMENT);
 
 	for (i = 0; i < 9; i++) {
 		const struct drm_color_lut *entry = &lut[i];
 
-		I915_WRITE(PREC_PAL_MULTI_SEG_DATA(pipe),
+		intel_dsb_indexed_reg_write(dsb, PREC_PAL_MULTI_SEG_DATA(pipe),
 					    ilk_lut_12p4_ldw(entry));
-		I915_WRITE(PREC_PAL_MULTI_SEG_DATA(pipe),
+		intel_dsb_indexed_reg_write(dsb, PREC_PAL_MULTI_SEG_DATA(pipe),
 					    ilk_lut_12p4_udw(entry));
 	}
+
+	intel_dsb_put(dsb);
 }
 
 static void
 icl_program_gamma_multi_segment(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);
 	const struct drm_property_blob *blob = crtc_state->base.gamma_lut;
 	const struct drm_color_lut *lut = blob->data;
 	const struct drm_color_lut *entry;
+	struct intel_dsb *dsb = intel_dsb_get(crtc);
 	enum pipe pipe = crtc->pipe;
 	u32 i;
 
@@ -862,12 +872,13 @@ icl_program_gamma_multi_segment(const struct intel_crtc_state *crtc_state)
 	 * PAL_PREC_INDEX[0] and PAL_PREC_INDEX[1] map to seg2[1],
 	 * seg2[0] being unused by the hardware.
 	 */
-	I915_WRITE(PREC_PAL_INDEX(pipe), PAL_PREC_AUTO_INCREMENT);
-
+	intel_dsb_reg_write(dsb, PREC_PAL_INDEX(pipe), PAL_PREC_AUTO_INCREMENT);
 	for (i = 1; i < 257; i++) {
 		entry = &lut[i * 8];
-		I915_WRITE(PREC_PAL_DATA(pipe), ilk_lut_12p4_ldw(entry));
-		I915_WRITE(PREC_PAL_DATA(pipe), ilk_lut_12p4_udw(entry));
+		intel_dsb_indexed_reg_write(dsb, PREC_PAL_DATA(pipe),
+					    ilk_lut_12p4_ldw(entry));
+		intel_dsb_indexed_reg_write(dsb, PREC_PAL_DATA(pipe),
+					    ilk_lut_12p4_udw(entry));
 	}
 
 	/*
@@ -884,20 +895,24 @@ icl_program_gamma_multi_segment(const struct intel_crtc_state *crtc_state)
 	 */
 	for (i = 0; i < 256; i++) {
 		entry = &lut[i * 8 * 128];
-		I915_WRITE(PREC_PAL_DATA(pipe), ilk_lut_12p4_ldw(entry));
-		I915_WRITE(PREC_PAL_DATA(pipe), ilk_lut_12p4_udw(entry));
+		intel_dsb_indexed_reg_write(dsb, PREC_PAL_DATA(pipe),
+					    ilk_lut_12p4_ldw(entry));
+		intel_dsb_indexed_reg_write(dsb, PREC_PAL_DATA(pipe),
+					    ilk_lut_12p4_udw(entry));
 	}
 
 	/* The last entry in the LUT is to be programmed in GCMAX */
 	entry = &lut[256 * 8 * 128];
 	icl_load_gcmax(crtc_state, entry);
 	ivb_load_lut_ext_max(crtc);
+	intel_dsb_put(dsb);
 }
 
 static void icl_load_luts(const struct intel_crtc_state *crtc_state)
 {
 	const struct drm_property_blob *gamma_lut = crtc_state->base.gamma_lut;
 	struct intel_crtc *crtc = to_intel_crtc(crtc_state->base.crtc);
+	struct intel_dsb *dsb = intel_dsb_get(crtc);
 
 	if (crtc_state->base.degamma_lut)
 		glk_load_degamma_lut(crtc_state);
@@ -914,6 +929,9 @@ static void icl_load_luts(const struct intel_crtc_state *crtc_state)
 		bdw_load_lut_10(crtc, gamma_lut, PAL_PREC_INDEX_VALUE(0));
 		ivb_load_lut_ext_max(crtc);
 	}
+
+	intel_dsb_commit(dsb);
+	intel_dsb_put(dsb);
 }
 
 static u32 chv_cgm_degamma_ldw(const struct drm_color_lut *color)