drm/i915: Implement color management on bdw/skl/bxt/kbl

Patch based on a previous series by Shashank Sharma.

v2: Do not read GAMMA_MODE register to figure what mode we're in

v3: Program PREC_PAL_GC_MAX to clamp pixel values > 1.0

    Add documentation on how the Broadcast RGB property is affected by CTM

v4: Update contributors

v5: Refactor degamma/gamma LUTs load into a single function

v6: Fix missing intel_crtc variable (bisect issue)

v7: Fix & simplify limited range matrix multiplication (Matt Roper's
    comment)

Signed-off-by: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: Kumar, Kiran S <kiran.s.kumar@intel.com>
Signed-off-by: Kausal Malladi <kausalmalladi@gmail.com>
Signed-off-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Acknowledged-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1458125837-2576-4-git-send-email-lionel.g.landwerlin@intel.com

Documentation/DocBook/gpu.tmpl

@@ -2153,7 +2153,11 @@ void intel_crt_init(struct drm_device *dev)
 	<td valign="top" >ENUM</td>
 	<td valign="top" >{ "Automatic", "Full", "Limited 16:235" }</td>
 	<td valign="top" >Connector</td>
-	<td valign="top" >TBD</td>
+	<td valign="top" >When this property is set to Limited 16:235
+		and CTM is set, the hardware will be programmed with the
+		result of the multiplication of CTM by the limited range
+		matrix to ensure the pixels normaly in the range 0..1.0 are
+		remapped to the range 16/255..235/255.</td>
 	</tr>
 	<tr>
 	<td valign="top" >“audio”</td>

drivers/gpu/drm/i915/i915_drv.c

@@ -66,6 +66,9 @@ static struct drm_driver driver;
 #define IVB_CURSOR_OFFSETS \
 	.cursor_offsets = { CURSOR_A_OFFSET, IVB_CURSOR_B_OFFSET, IVB_CURSOR_C_OFFSET }
 
+#define BDW_COLORS \
+	.color = { .degamma_lut_size = 512, .gamma_lut_size = 512 }
+
 static const struct intel_device_info intel_i830_info = {
 	.gen = 2, .is_mobile = 1, .cursor_needs_physical = 1, .num_pipes = 2,
 	.has_overlay = 1, .overlay_needs_physical = 1,
@@ -288,24 +291,28 @@ static const struct intel_device_info intel_haswell_m_info = {
 	.is_mobile = 1,
 };
 
+#define BDW_FEATURES \
+	HSW_FEATURES, \
+	BDW_COLORS
+
 static const struct intel_device_info intel_broadwell_d_info = {
-	HSW_FEATURES,
+	BDW_FEATURES,
 	.gen = 8,
 };
 
 static const struct intel_device_info intel_broadwell_m_info = {
-	HSW_FEATURES,
+	BDW_FEATURES,
 	.gen = 8, .is_mobile = 1,
 };
 
 static const struct intel_device_info intel_broadwell_gt3d_info = {
-	HSW_FEATURES,
+	BDW_FEATURES,
 	.gen = 8,
 	.ring_mask = RENDER_RING | BSD_RING | BLT_RING | VEBOX_RING | BSD2_RING,
 };
 
 static const struct intel_device_info intel_broadwell_gt3m_info = {
-	HSW_FEATURES,
+	BDW_FEATURES,
 	.gen = 8, .is_mobile = 1,
 	.ring_mask = RENDER_RING | BSD_RING | BLT_RING | VEBOX_RING | BSD2_RING,
 };
@@ -321,13 +328,13 @@ static const struct intel_device_info intel_cherryview_info = {
 };
 
 static const struct intel_device_info intel_skylake_info = {
-	HSW_FEATURES,
+	BDW_FEATURES,
 	.is_skylake = 1,
 	.gen = 9,
 };
 
 static const struct intel_device_info intel_skylake_gt3_info = {
-	HSW_FEATURES,
+	BDW_FEATURES,
 	.is_skylake = 1,
 	.gen = 9,
 	.ring_mask = RENDER_RING | BSD_RING | BLT_RING | VEBOX_RING | BSD2_RING,
@@ -345,17 +352,18 @@ static const struct intel_device_info intel_broxton_info = {
 	.has_fbc = 1,
 	GEN_DEFAULT_PIPEOFFSETS,
 	IVB_CURSOR_OFFSETS,
+	BDW_COLORS,
 };
 
 static const struct intel_device_info intel_kabylake_info = {
-	HSW_FEATURES,
+	BDW_FEATURES,
 	.is_preliminary = 1,
 	.is_kabylake = 1,
 	.gen = 9,
 };
 
 static const struct intel_device_info intel_kabylake_gt3_info = {
-	HSW_FEATURES,
+	BDW_FEATURES,
 	.is_preliminary = 1,
 	.is_kabylake = 1,
 	.gen = 9,

drivers/gpu/drm/i915/i915_drv.h

@@ -630,6 +630,7 @@ struct drm_i915_display_funcs {
 	/* display clock increase/decrease */
 	/* pll clock increase/decrease */
 
+	void (*load_csc_matrix)(struct drm_crtc *crtc);
 	void (*load_luts)(struct drm_crtc *crtc);
 };
 
@@ -781,6 +782,11 @@ struct intel_device_info {
 	u8 has_slice_pg:1;
 	u8 has_subslice_pg:1;
 	u8 has_eu_pg:1;
+
+	struct color_luts {
+		u16 degamma_lut_size;
+		u16 gamma_lut_size;
+	} color;
 };
 
 #undef DEFINE_FLAG

drivers/gpu/drm/i915/i915_reg.h

@@ -7663,6 +7663,28 @@ enum skl_disp_power_wells {
 #define PIPE_CSC_POSTOFF_ME(pipe)	_MMIO_PIPE(pipe, _PIPE_A_CSC_POSTOFF_ME, _PIPE_B_CSC_POSTOFF_ME)
 #define PIPE_CSC_POSTOFF_LO(pipe)	_MMIO_PIPE(pipe, _PIPE_A_CSC_POSTOFF_LO, _PIPE_B_CSC_POSTOFF_LO)
 
+/* pipe degamma/gamma LUTs on IVB+ */
+#define _PAL_PREC_INDEX_A	0x4A400
+#define _PAL_PREC_INDEX_B	0x4AC00
+#define _PAL_PREC_INDEX_C	0x4B400
+#define   PAL_PREC_10_12_BIT		(0 << 31)
+#define   PAL_PREC_SPLIT_MODE		(1 << 31)
+#define   PAL_PREC_AUTO_INCREMENT	(1 << 15)
+#define _PAL_PREC_DATA_A	0x4A404
+#define _PAL_PREC_DATA_B	0x4AC04
+#define _PAL_PREC_DATA_C	0x4B404
+#define _PAL_PREC_GC_MAX_A	0x4A410
+#define _PAL_PREC_GC_MAX_B	0x4AC10
+#define _PAL_PREC_GC_MAX_C	0x4B410
+#define _PAL_PREC_EXT_GC_MAX_A	0x4A420
+#define _PAL_PREC_EXT_GC_MAX_B	0x4AC20
+#define _PAL_PREC_EXT_GC_MAX_C	0x4B420
+
+#define PREC_PAL_INDEX(pipe)		_MMIO_PIPE(pipe, _PAL_PREC_INDEX_A, _PAL_PREC_INDEX_B)
+#define PREC_PAL_DATA(pipe)		_MMIO_PIPE(pipe, _PAL_PREC_DATA_A, _PAL_PREC_DATA_B)
+#define PREC_PAL_GC_MAX(pipe, i)	_MMIO(_PIPE(pipe, _PAL_PREC_GC_MAX_A, _PAL_PREC_GC_MAX_B) + (i) * 4)
+#define PREC_PAL_EXT_GC_MAX(pipe, i)	_MMIO(_PIPE(pipe, _PAL_PREC_EXT_GC_MAX_A, _PAL_PREC_EXT_GC_MAX_B) + (i) * 4)
+
 /* MIPI DSI registers */
 
 #define _MIPI_PORT(port, a, c)	_PORT3(port, a, 0, c)	/* ports A and C only */