[PATCH v4 10/12] drm/display/dsc: Add flatness and initial scale value calculations

[Dmitry Baryshkov]

From: Jessica Zhang <quic_jesszhan at quicinc.com>

Add helpers to calculate det_thresh_flatness and initial_scale_value as
these calculations are defined within the DSC spec.

Changes in v2:
- Renamed det_thresh_flatness to flatness_det_thresh
- Set initial_scale_value directly in helper

Signed-off-by: Jessica Zhang <quic_jesszhan at quicinc.com>
Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>
---
 include/drm/display/drm_dsc_helper.h | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/include/drm/display/drm_dsc_helper.h b/include/drm/display/drm_dsc_helper.h
index 4448c482b092..bfa7f3acafcb 100644
--- a/include/drm/display/drm_dsc_helper.h
+++ b/include/drm/display/drm_dsc_helper.h
@@ -26,5 +26,16 @@ void drm_dsc_set_rc_buf_thresh(struct drm_dsc_config *vdsc_cfg);
 int drm_dsc_setup_rc_params(struct drm_dsc_config *vdsc_cfg, enum drm_dsc_params_kind kind);
 int drm_dsc_compute_rc_parameters(struct drm_dsc_config *vdsc_cfg);
 
+static inline void drm_dsc_set_initial_scale_value(struct drm_dsc_config *dsc)
+{
+	dsc->initial_scale_value = 8 * dsc->rc_model_size /
+		(dsc->rc_model_size - dsc->initial_offset);
+}
+
+static inline int drm_dsc_calculate_flatness_det_thresh(struct drm_dsc_config *dsc)
+{
+	return 2 << (dsc->bits_per_component - 8);
+}
+
 #endif /* _DRM_DSC_HELPER_H_ */
 
-- 
2.39.2