[PATCH 09/18] drm/i915: Pipe level Gamma correction for CHV/BSW

Shashank Sharma
2015-08-06T16:38:18Z

From: Kausal Malladi <kausalmalladi@gmail.com>

CHV/BSW platform supports two different pipe level gamma
correction modes, which are:
1. Legacy 8-bit mode
2. 10-bit CGM (Color Gamut Mapping) mode

This patch does the following:
1. Attaches Gamma property to CRTC
3. Adds the core Gamma correction function for CHV/BSW
4. Adds Gamma correction macros

Signed-off-by: Shashank Sharma <shashank.sharma@intel.com>
Signed-off-by: Kausal Malladi <kausalmalladi@gmail.com>
---
drivers/gpu/drm/i915/i915_reg.h | 12 +++
drivers/gpu/drm/i915/intel_color_manager.c | 146 +++++++++++++++++++++++++++++
drivers/gpu/drm/i915/intel_color_manager.h | 20 ++++
drivers/gpu/drm/i915/intel_display.c | 2 +
drivers/gpu/drm/i915/intel_drv.h | 2 +
5 files changed, 182 insertions(+)

diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 3a77678..4997ebd 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -7921,4 +7921,16 @@ enum skl_disp_power_wells {
#define GEN9_VEBOX_MOCS_0 0xcb00 /* Video MOCS base register*/
#define GEN9_BLT_MOCS_0 0xcc00 /* Blitter MOCS base register*/

+/* Color Management */
+#define PIPEA_CGM_CONTROL (VLV_DISPLAY_BASE + 0x67A00)
+#define PIPEB_CGM_CONTROL (VLV_DISPLAY_BASE + 0x69A00)
+#define PIPEC_CGM_CONTROL (VLV_DISPLAY_BASE + 0x6BA00)
+#define PIPEA_CGM_GAMMA (VLV_DISPLAY_BASE + 0x67000)
+#define PIPEB_CGM_GAMMA (VLV_DISPLAY_BASE + 0x69000)
+#define PIPEC_CGM_GAMMA (VLV_DISPLAY_BASE + 0x6B000)
+#define _PIPE_CGM_CONTROL(pipe) \
+ (_PIPE3(pipe, PIPEA_CGM_CONTROL, PIPEB_CGM_CONTROL, PIPEC_CGM_CONTROL))
+#define _PIPE_GAMMA_BASE(pipe) \
+ (_PIPE3(pipe, PIPEA_CGM_GAMMA, PIPEB_CGM_GAMMA, PIPEC_CGM_GAMMA))
+
#endif /* _I915_REG_H_ */
diff --git a/drivers/gpu/drm/i915/intel_color_manager.c b/drivers/gpu/drm/i915/intel_color_manager.c
index 9a6126c..f8c8d26 100644
--- a/drivers/gpu/drm/i915/intel_color_manager.c
+++ b/drivers/gpu/drm/i915/intel_color_manager.c
@@ -27,6 +27,149 @@

#include "intel_color_manager.h"

+int chv_set_gamma(struct drm_device *dev, struct drm_property_blob *blob,
+ struct drm_crtc *crtc)
+{
+ bool flag = false;
+ enum pipe pipe;
+ u8 red_int, blue_int, green_int;
+ u16 red_fract, green_fract, blue_fract;
+ u32 red, green, blue;
+ u32 cgm_control_reg = 0;
+ u32 cgm_gamma_reg = 0;
+ u32 count = 0, num_samples, word;
+ int ret = 0, length;
+ struct drm_r32g32b32 *correction_values = NULL;
+ struct drm_palette *gamma_data;
+ struct drm_i915_private *dev_priv = dev->dev_private;
+
+ if (!blob) {
+ DRM_ERROR("NULL Blob\n");
+ return -EINVAL;
+ }
+
+ gamma_data = (struct drm_palette *)blob->data;
+
+ if (gamma_data->version != CHV_GAMMA_DATA_STRUCT_VERSION) {
+ DRM_ERROR("Invalid Gamma Data struct version\n");
+ return -EINVAL;
+ }
+
+ pipe = to_intel_crtc(crtc)->pipe;
+ num_samples = gamma_data->num_samples;
+ length = num_samples * sizeof(struct drm_r32g32b32);
+
+ switch (num_samples) {
+ case 0:
+
+ /* Disable Gamma functionality on Pipe - CGM Block */
+ cgm_control_reg = I915_READ(_PIPE_CGM_CONTROL(pipe));
+ cgm_control_reg &= ~CGM_GAMMA_EN;
+ I915_WRITE(_PIPE_CGM_CONTROL(pipe), cgm_control_reg);
+
+ DRM_DEBUG_DRIVER("Gamma disabled on Pipe %c\n",
+ pipe_name(pipe));
+ ret = 0;
+ break;
+
+ case CHV_8BIT_GAMMA_MAX_VALS:
+ case CHV_10BIT_GAMMA_MAX_VALS:
+
+ count = 0;
+ cgm_gamma_reg = _PIPE_GAMMA_BASE(pipe);
+ correction_values = (struct drm_r32g32b32 *)&gamma_data->lut;
+
+ while (count < num_samples) {
+ blue = correction_values[count].b32;
+ green = correction_values[count].g32;
+ red = correction_values[count].r32;
+
+ blue_int = _GAMMA_INT_PART(blue);
+ if (blue_int > GAMMA_INT_MAX)
+ blue = CHV_MAX_GAMMA;
+
+ green_int = _GAMMA_INT_PART(green);
+ if (green_int > GAMMA_INT_MAX)
+ green = CHV_MAX_GAMMA;
+
+ red_int = _GAMMA_INT_PART(red);
+ if (red_int > GAMMA_INT_MAX)
+ red = CHV_MAX_GAMMA;
+
+ blue_fract = _GAMMA_FRACT_PART(blue);
+ green_fract = _GAMMA_FRACT_PART(green);
+ red_fract = _GAMMA_FRACT_PART(red);
+
+ blue_fract >>= CHV_10BIT_GAMMA_MSB_SHIFT;
+ green_fract >>= CHV_10BIT_GAMMA_MSB_SHIFT;
+ red_fract >>= CHV_10BIT_GAMMA_MSB_SHIFT;
+
+ /* Green (25:16) and Blue (9:0) to be written */
+ word = green_fract;
+ word <<= CHV_GAMMA_SHIFT_GREEN;
+ word |= blue_fract;
+ I915_WRITE(cgm_gamma_reg, word);
+ cgm_gamma_reg += 4;
+
+ /* Red (9:0) to be written */
+ word = red_fract;
+ I915_WRITE(cgm_gamma_reg, word);
+
+ cgm_gamma_reg += 4;
+ count++;
+
+ /*
+ * On CHV, the best supported Gamma capability is
+ * CGM block, that takes 257 samples.
+ * If user gives 256 samples (legacy mode), then
+ * duplicate the 256th value to 257th.
+ * "flag" is used to make sure it happens only once
+ */
+ if (num_samples == CHV_8BIT_GAMMA_MAX_VALS
+ && count == CHV_8BIT_GAMMA_MAX_VALS
+ && !flag) {
+ count--;
+ flag = true;
+ }
+ }
+
+ /* Enable (CGM) Gamma on Pipe */
+ I915_WRITE(_PIPE_CGM_CONTROL(pipe),
+ I915_READ(_PIPE_CGM_CONTROL(pipe))
+ | CGM_GAMMA_EN);
+ DRM_DEBUG_DRIVER("CGM Gamma enabled on Pipe %c\n",
+ pipe_name(pipe));
+ ret = 0;
+ break;
+
+ default:
+ DRM_ERROR("Invalid number of samples for Gamma LUT\n");
+ ret = -EINVAL;
+ }
+
+ return ret;
+}
+
+void intel_color_manager_crtc_commit(struct drm_device *dev,
+ struct drm_crtc_state *crtc_state)
+{
+ struct drm_property_blob *blob;
+ struct drm_crtc *crtc = crtc_state->crtc;
+ int ret = -EINVAL;
+
+ blob = crtc_state->palette_after_ctm_blob;
+ if (blob) {
+ /* Gamma correction is platform specific */
+ if (IS_CHERRYVIEW(dev))
+ ret = chv_set_gamma(dev, blob, crtc);
+
+ if (ret)
+ DRM_ERROR("set Gamma correction failed\n");
+ else
+ DRM_DEBUG_DRIVER("Gamma correction success\n");
+ }
+}
+
int intel_color_manager_set_pipe_gamma(struct drm_device *dev,
struct drm_crtc_state *crtc_state,
struct drm_mode_object *obj, uint32_t blob_id)
@@ -99,5 +242,8 @@ void intel_attach_color_properties_to_crtc(struct drm_device *dev,
drm_object_attach_property(mode_obj,
config->cm_crtc_palette_capabilities_property,
capabilities_blob_id);
+ if (config->cm_palette_after_ctm_property)
+ drm_object_attach_property(mode_obj,
+ config->cm_palette_after_ctm_property, 0);
}
}
diff --git a/drivers/gpu/drm/i915/intel_color_manager.h b/drivers/gpu/drm/i915/intel_color_manager.h
index 51aeb91..8bbac20 100644
--- a/drivers/gpu/drm/i915/intel_color_manager.h
+++ b/drivers/gpu/drm/i915/intel_color_manager.h
@@ -28,6 +28,26 @@
#include <drm/drm_crtc_helper.h>
#include "i915_drv.h"

+#define _GAMMA_INT_PART(value) (value >> GAMMA_INT_SHIFT)
+#define _GAMMA_FRACT_PART(value) (value >> GAMMA_FRACT_SHIFT)
+
#define CHV_PALETTE_STRUCT_VERSION 1
#define CHV_DEGAMMA_MAX_VALS 65
#define CHV_10BIT_GAMMA_MAX_VALS 257
+
+/* Gamma correction */
+#define CHV_GAMMA_DATA_STRUCT_VERSION 1
+#define CHV_10BIT_GAMMA_MAX_VALS 257
+#define CHV_8BIT_GAMMA_MAX_VALS 256
+#define CHV_10BIT_GAMMA_MSB_SHIFT 6
+#define CHV_GAMMA_SHIFT_GREEN 16
+/* Gamma values are u8.24 format */
+#define GAMMA_INT_SHIFT 24
+#define GAMMA_FRACT_SHIFT 8
+/* Max int value for Gamma is 1 */
+#define GAMMA_INT_MAX 1
+/* Max value for Gamma on CHV */
+#define CHV_MAX_GAMMA 0x10000
+
+/* CHV CGM Block */
+#define CGM_GAMMA_EN (1 << 2)
diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c
index 349a1c2..9d1a6c3 100644
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -13641,6 +13641,8 @@ static void intel_begin_crtc_commit(struct drm_crtc *crtc,

if (!needs_modeset(crtc->state) && INTEL_INFO(dev)->gen >= 9)
skl_detach_scalers(intel_crtc);
+
+ intel_color_manager_crtc_commit(dev, crtc->state);
}

static void intel_finish_crtc_commit(struct drm_crtc *crtc,
diff --git a/drivers/gpu/drm/i915/intel_drv.h b/drivers/gpu/drm/i915/intel_drv.h
index 820ded7..de3e6e7 100644
--- a/drivers/gpu/drm/i915/intel_drv.h
+++ b/drivers/gpu/drm/i915/intel_drv.h
@@ -1444,5 +1444,7 @@ void intel_attach_color_properties_to_crtc(struct drm_device *dev,
int intel_color_manager_set_pipe_gamma(struct drm_device *dev,
struct drm_crtc_state *crtc_state,
struct drm_mode_object *obj, uint32_t blob_id);
+void intel_color_manager_crtc_commit(struct drm_device *dev,
+ struct drm_crtc_state *crtc_state);

#endif /* __INTEL_DRV_H__ */