[PATCH V8 32/43] drm/colorop: Add 1D Curve Custom LUT type

[Alex Hung <alex.hung@amd.com>]

We've previously introduced DRM_COLOROP_1D_CURVE for
pre-defined 1D curves. But we also have HW that supports
custom curves and userspace needs the ability to pass
custom curves, aka LUTs.

This patch introduces a new colorop type, called
DRM_COLOROP_1D_LUT that provides a SIZE property which
is used by a driver to advertise the supported SIZE
of the LUT, as well as a DATA property which userspace
uses to set the LUT.

DATA and size function in the same way as current drm_crtc
GAMMA and DEGAMMA LUTs.

Signed-off-by: Alex Hung <alex.hung@amd.com>
Co-developed-by: Harry Wentland <harry.wentland@amd.com>
Signed-off-by: Harry Wentland <harry.wentland@amd.com>
---
v8:
 - Add DRM_MODE_PROP_ATOMIC to drm_property_create_range (Simon Ser)
 - Change "1D Curve Custom LUT" to "1D LUT" (Simon Ser)

v7:
 - Change "size" to "lut_size" (this affects multiple following commits)
 - Move "lut_size" from drm_colorop_state to drm_colorop
 - Modify other files accordingly (i.e. from drm_colorop_state->size
   to drm_colorop->lut_size)

v5:
 - Add kernel doc
 - Define SIZE in similar manner to GAMMA_SIZE on drm_crtc (Melissa)

 drivers/gpu/drm/drm_atomic.c      |  4 +++
 drivers/gpu/drm/drm_atomic_uapi.c |  5 ++++
 drivers/gpu/drm/drm_colorop.c     | 43 +++++++++++++++++++++++++++++++
 include/drm/drm_colorop.h         | 16 ++++++++++++
 include/uapi/drm/drm_mode.h       | 14 ++++++++++
 5 files changed, 82 insertions(+)

diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index 5223cf363692..f713d177241d 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -793,6 +793,10 @@ static void drm_atomic_colorop_print_state(struct drm_printer *p,
 		drm_printf(p, "\tcurve_1d_type=%s\n",
 			   drm_get_colorop_curve_1d_type_name(state->curve_1d_type));
 		break;
+	case DRM_COLOROP_1D_LUT:
+		drm_printf(p, "\tsize=%d\n", colorop->lut_size);
+		drm_printf(p, "\tdata blob id=%d\n", state->data ? state->data->base.id : 0);
+		break;
 	case DRM_COLOROP_CTM_3X4:
 		drm_printf(p, "\tdata blob id=%d\n", state->data ? state->data->base.id : 0);
 		break;
diff --git a/drivers/gpu/drm/drm_atomic_uapi.c b/drivers/gpu/drm/drm_atomic_uapi.c
index dcd12fc0bd8f..dfd88a227da7 100644
--- a/drivers/gpu/drm/drm_atomic_uapi.c
+++ b/drivers/gpu/drm/drm_atomic_uapi.c
@@ -713,6 +713,9 @@ static int drm_atomic_color_set_data_property(struct drm_colorop *colorop,
 	bool replaced = false;
 
 	switch (colorop->type) {
+	case DRM_COLOROP_1D_LUT:
+		size = colorop->lut_size * sizeof(struct drm_color_lut);
+		break;
 	case DRM_COLOROP_CTM_3X4:
 		size = sizeof(struct drm_color_ctm_3x4);
 		break;
@@ -762,6 +765,8 @@ drm_atomic_colorop_get_property(struct drm_colorop *colorop,
 		*val = state->bypass;
 	} else if (property == colorop->curve_1d_type_property) {
 		*val = state->curve_1d_type;
+	} else if (property == colorop->lut_size_property) {
+		*val = colorop->lut_size;
 	} else if (property == colorop->data_property) {
 		*val = (state->data) ? state->data->base.id : 0;
 	} else {
diff --git a/drivers/gpu/drm/drm_colorop.c b/drivers/gpu/drm/drm_colorop.c
index fcb4a8d0e38d..15ffbba60b3d 100644
--- a/drivers/gpu/drm/drm_colorop.c
+++ b/drivers/gpu/drm/drm_colorop.c
@@ -64,6 +64,7 @@
 
 static const struct drm_prop_enum_list drm_colorop_type_enum_list[] = {
 	{ DRM_COLOROP_1D_CURVE, "1D Curve" },
+	{ DRM_COLOROP_1D_LUT, "1D LUT" },
 	{ DRM_COLOROP_CTM_3X4, "3x4 Matrix"},
 };
 
@@ -225,6 +226,47 @@ static int drm_colorop_create_data_prop(struct drm_device *dev, struct drm_color
 	return 0;
 }
 
+/**
+ * drm_colorop_curve_1d_lut_init - Initialize a DRM_COLOROP_1D_LUT
+ *
+ * @dev: DRM device
+ * @colorop: The drm_colorop object to initialize
+ * @plane: The associated drm_plane
+ * @lut_size: LUT size supported by driver
+ * @return zero on success, -E value on failure
+ */
+int drm_colorop_curve_1d_lut_init(struct drm_device *dev, struct drm_colorop *colorop,
+				  struct drm_plane *plane, uint32_t lut_size)
+{
+	struct drm_property *prop;
+	int ret;
+
+	ret = drm_colorop_init(dev, colorop, plane, DRM_COLOROP_1D_LUT);
+	if (ret)
+		return ret;
+
+	/* initialize 1D LUT only attribute */
+	/* LUT size */
+	prop = drm_property_create_range(dev, DRM_MODE_PROP_IMMUTABLE | DRM_MODE_PROP_ATOMIC,
+					 "SIZE", 0, UINT_MAX);
+	if (!prop)
+		return -ENOMEM;
+
+	colorop->lut_size_property = prop;
+	drm_object_attach_property(&colorop->base, colorop->lut_size_property, lut_size);
+	colorop->lut_size = lut_size;
+
+	/* data */
+	ret = drm_colorop_create_data_prop(dev, colorop);
+	if (ret)
+		return ret;
+
+	drm_colorop_reset(colorop);
+
+	return 0;
+}
+EXPORT_SYMBOL(drm_colorop_curve_1d_lut_init);
+
 int drm_colorop_ctm_3x4_init(struct drm_device *dev, struct drm_colorop *colorop,
 			     struct drm_plane *plane)
 {
@@ -333,6 +375,7 @@ void drm_colorop_reset(struct drm_colorop *colorop)
 
 static const char * const colorop_type_name[] = {
 	[DRM_COLOROP_1D_CURVE] = "1D Curve",
+	[DRM_COLOROP_1D_LUT] = "1D LUT",
 	[DRM_COLOROP_CTM_3X4] = "3x4 Matrix",
 };
 
diff --git a/include/drm/drm_colorop.h b/include/drm/drm_colorop.h
index d3a60c1beed1..d66c76033343 100644
--- a/include/drm/drm_colorop.h
+++ b/include/drm/drm_colorop.h
@@ -259,6 +259,13 @@ struct drm_colorop {
 	 */
 	struct drm_property *bypass_property;
 
+	/**
+	 * @lut_size:
+	 *
+	 * Number of entries of the custom LUT. This should be read-only.
+	 */
+	uint32_t lut_size;
+
 	/**
 	 * @curve_1d_type_property:
 	 *
@@ -266,6 +273,13 @@ struct drm_colorop {
 	 */
 	struct drm_property *curve_1d_type_property;
 
+	/**
+	 * @lut_size_property:
+	 *
+	 * Size property for custom LUT from userspace.
+	 */
+	struct drm_property *lut_size_property;
+
 	/**
 	 * @data_property:
 	 *
@@ -310,6 +324,8 @@ static inline struct drm_colorop *drm_colorop_find(struct drm_device *dev,
 
 int drm_colorop_curve_1d_init(struct drm_device *dev, struct drm_colorop *colorop,
 			      struct drm_plane *plane, u64 supported_tfs);
+int drm_colorop_curve_1d_lut_init(struct drm_device *dev, struct drm_colorop *colorop,
+				  struct drm_plane *plane, uint32_t lut_size);
 int drm_colorop_ctm_3x4_init(struct drm_device *dev, struct drm_colorop *colorop,
 			     struct drm_plane *plane);
 
diff --git a/include/uapi/drm/drm_mode.h b/include/uapi/drm/drm_mode.h
index 651bdf48b766..dde250dd7a51 100644
--- a/include/uapi/drm/drm_mode.h
+++ b/include/uapi/drm/drm_mode.h
@@ -890,6 +890,20 @@ enum drm_colorop_type {
 	 */
 	DRM_COLOROP_1D_CURVE,
 
+	/**
+	 * @DRM_COLOROP_1D_LUT:
+	 *
+	 * enum string "1D LUT"
+	 *
+	 * A simple 1D LUT of uniformly spaced &drm_color_lut entries,
+	 * packed into a blob via the DATA property. The driver's
+	 * expected LUT size is advertised via the SIZE property.
+	 *
+	 * The DATA blob is an array of struct drm_color_lut with size
+	 * of "lut_size".
+	 */
+	DRM_COLOROP_1D_LUT,
+
 	/**
 	 * @DRM_COLOROP_CTM_3X4:
 	 *
-- 
2.43.0