CHV/BSW platform supports various Gamma correction modes, which are:
1. Legacy 8-bit mode
2. 10-bit CGM (Color Gamut Mapping) mode
This patch does the following:
1. Adds the core function to program Gamma correction values for CHV/BSW
platform
2. Adds Gamma correction macros/defines
Signed-off-by: Shashank Sharma <shashank.sharma@xxxxxxxxx>
Signed-off-by: Kausal Malladi <Kausal.Malladi@xxxxxxxxx>
---
drivers/gpu/drm/i915/i915_reg.h | 12 +++
drivers/gpu/drm/i915/intel_color_manager.c | 149 +++++++++++++++++++++++++++++
drivers/gpu/drm/i915/intel_color_manager.h | 20 ++++
drivers/gpu/drm/i915/intel_display.c | 3 +
drivers/gpu/drm/i915/intel_drv.h | 2 +
5 files changed, 186 insertions(+)
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 059de0f..4ec2e4f 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -7906,4 +7906,16 @@ enum skl_disp_power_wells {
#define _PALETTE_A (dev_priv->info.display_mmio_offset + 0xa000)
#define _PALETTE_B (dev_priv->info.display_mmio_offset + 0xa800)
+/* 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 70c0d42..7e9e934 100644
--- a/drivers/gpu/drm/i915/intel_color_manager.c
+++ b/drivers/gpu/drm/i915/intel_color_manager.c
@@ -27,6 +27,155 @@
#include "intel_color_manager.h"
+int chv_set_gamma(struct drm_device *dev, struct drm_property_blob *blob,
+ struct drm_crtc *crtc)
+{
+ struct drm_palette *gamma_data;
+ struct drm_i915_private *dev_priv = dev->dev_private;
+ struct drm_mode_config *config = &dev->mode_config;
+ u32 cgm_control_reg = 0;
+ u32 cgm_gamma_reg = 0;
+ enum pipe pipe;
+ u32 red, green, blue;
+ u8 red_int, blue_int, green_int;
+ u16 red_fract, green_fract, blue_fract;
+ u32 count = 0;
+ struct drm_r32g32b32 *correction_values = NULL;
+ u32 num_samples;
+ u32 word;
+ int ret = 0, length, flag = 0;
+
+ 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);
+
+ if (num_samples == 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;
+ } else if (num_samples == CHV_10BIT_GAMMA_MAX_VALS ||
+ num_samples == CHV_8BIT_GAMMA_MAX_VALS) {
+ cgm_gamma_reg = _PIPE_GAMMA_BASE(pipe);
+
+ count = 0;
+ 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 = 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 = 1;
+ }
+ }
+
+ DRM_DEBUG_DRIVER("Gamma LUT loaded successfully for Pipe %c\n",
+ pipe_name(pipe));
+
+ /* 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;
+ } else {
+ DRM_ERROR("Invalid number of samples for Gamma LUT\n");
+ return -EINVAL;
+ }
+
+ ret = drm_property_replace_global_blob(dev, &blob, length,
+ (void *) gamma_data, &crtc->base,
+ config->prop_palette_after_ctm);
