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 at intel.com>
Signed-off-by: Kausal Malladi <kausalmalladi at gmail.com>
---
drivers/gpu/drm/i915/i915_reg.h | 12 +++
drivers/gpu/drm/i915/intel_color_manager.c | 114 +++++++++++++++++++++++++++++
drivers/gpu/drm/i915/intel_color_manager.h | 13 ++++
3 files changed, 139 insertions(+)
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 60e6a73..885ac8a 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -8038,4 +8038,16 @@ 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 e466748..cf381b8 100644
--- a/drivers/gpu/drm/i915/intel_color_manager.c
+++ b/drivers/gpu/drm/i915/intel_color_manager.c
@@ -27,6 +27,112 @@
#include "intel_color_manager.h"
+static int chv_set_gamma(struct drm_device *dev, struct drm_property_blob
*blob,
+ struct drm_crtc *crtc)
+{
+ bool flag = false;
+ enum pipe pipe;
+ u16 red_fract, green_fract, blue_fract;
+ u32 red, green, blue, num_samples;
+ u32 word = 0;
+ u32 count = 0;
+ u32 cgm_gamma_reg = 0;
+ u32 cgm_control_reg = 0;
+ 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 (WARN_ON(!blob))
+ return -EINVAL;
+
+ gamma_data = (struct drm_palette *)blob->data;
+ pipe = to_intel_crtc(crtc)->pipe;
+ num_samples = gamma_data->num_samples;
+ length = num_samples * sizeof(struct drm_r32g32b32);
+
+ switch (num_samples) {
+ case GAMMA_DISABLE_VALS:
+
+ /* 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;
+
+ if (blue > CHV_MAX_GAMMA)
+ blue = CHV_MAX_GAMMA;
+
+ if (green > CHV_MAX_GAMMA)
+ green = CHV_MAX_GAMMA;
+
+ if (red > CHV_MAX_GAMMA)
+ red = CHV_MAX_GAMMA;
+
+ /* get MSB 10 bits from fraction part (14:23) */
+ blue_fract = GET_BITS(blue, 14, 10);
+ green_fract = GET_BITS(green, 14, 10);
+ red_fract = GET_BITS(red, 14, 10);
+
+ /* Green (25:16) and Blue (9:0) to be written */
+ SET_BITS(word, green_fract, 16, 10);
+ SET_BITS(word, blue_fract, 0, 10);
+ 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_attach_color_properties_to_crtc(struct drm_device *dev,
struct drm_crtc *crtc)
{
@@ -61,4 +167,12 @@ void intel_attach_color_properties_to_crtc(struct
drm_device *dev,
INTEL_INFO(dev)->num_samples_before_ctm);
DRM_DEBUG_DRIVER("Degamma query property initialized\n");
}
+
+ /* Gamma correction */
+ if (config->cm_palette_after_ctm_property) {
+ drm_object_attach_property(mode_obj,
+ config->cm_palette_after_ctm_property, 0);
+ DRM_DEBUG_DRIVER("gamma property attached to CRTC\n");
+ }
+
}
diff --git a/drivers/gpu/drm/i915/intel_color_manager.h
b/drivers/gpu/drm/i915/intel_color_manager.h
index 14a1309..de706d9 100644
--- a/drivers/gpu/drm/i915/intel_color_manager.h
+++ b/drivers/gpu/drm/i915/intel_color_manager.h
@@ -52,3 +52,16 @@
/* CHV */
#define CHV_10BIT_GAMMA_MAX_VALS 257
#define CHV_DEGAMMA_MAX_VALS 65
+
+/* No of coeff for disabling gamma is 0 */
+#define GAMMA_DISABLE_VALS 0
+
+/* Gamma on CHV */
+#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
+#define CHV_MAX_GAMMA ((1 << 24) - 1)
+
+/* CHV CGM Block */
+#define CGM_GAMMA_EN (1 << 2)
--
1.9.1
