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-rw-r--r--drivers/gpu/drm/i915/display/intel_display.c99
-rw-r--r--drivers/gpu/drm/i915/display/intel_display.h4
2 files changed, 103 insertions, 0 deletions
diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index 6ae085c6b361..e829203befad 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -6289,6 +6289,105 @@ void skl_scaler_disable(const struct intel_crtc_state *old_crtc_state)
skl_detach_scaler(crtc, i);
}
+static int cnl_coef_tap(int i)
+{
+ return i % 7;
+}
+
+static u16 cnl_nearest_filter_coef(int t)
+{
+ return t == 3 ? 0x0800 : 0x3000;
+}
+
+/**
+ * Theory behind setting nearest-neighbor integer scaling:
+ *
+ * 17 phase of 7 taps requires 119 coefficients in 60 dwords per set.
+ * The letter represents the filter tap (D is the center tap) and the number
+ * represents the coefficient set for a phase (0-16).
+ *
+ * +------------+------------------------+------------------------+
+ * |Index value | Data value coeffient 1 | Data value coeffient 2 |
+ * +------------+------------------------+------------------------+
+ * | 00h | B0 | A0 |
+ * +------------+------------------------+------------------------+
+ * | 01h | D0 | C0 |
+ * +------------+------------------------+------------------------+
+ * | 02h | F0 | E0 |
+ * +------------+------------------------+------------------------+
+ * | 03h | A1 | G0 |
+ * +------------+------------------------+------------------------+
+ * | 04h | C1 | B1 |
+ * +------------+------------------------+------------------------+
+ * | ... | ... | ... |
+ * +------------+------------------------+------------------------+
+ * | 38h | B16 | A16 |
+ * +------------+------------------------+------------------------+
+ * | 39h | D16 | C16 |
+ * +------------+------------------------+------------------------+
+ * | 3Ah | F16 | C16 |
+ * +------------+------------------------+------------------------+
+ * | 3Bh | Reserved | G16 |
+ * +------------+------------------------+------------------------+
+ *
+ * To enable nearest-neighbor scaling: program scaler coefficents with
+ * the center tap (Dxx) values set to 1 and all other values set to 0 as per
+ * SCALER_COEFFICIENT_FORMAT
+ *
+ */
+
+static void cnl_program_nearest_filter_coefs(struct drm_i915_private *dev_priv,
+ enum pipe pipe, int id, int set)
+{
+ int i;
+
+ intel_de_write_fw(dev_priv, CNL_PS_COEF_INDEX_SET(pipe, id, set),
+ PS_COEE_INDEX_AUTO_INC);
+
+ for (i = 0; i < 17 * 7; i += 2) {
+ u32 tmp;
+ int t;
+
+ t = cnl_coef_tap(i);
+ tmp = cnl_nearest_filter_coef(t);
+
+ t = cnl_coef_tap(i + 1);
+ tmp |= cnl_nearest_filter_coef(t) << 16;
+
+ intel_de_write_fw(dev_priv, CNL_PS_COEF_DATA_SET(pipe, id, set),
+ tmp);
+ }
+
+ intel_de_write_fw(dev_priv, CNL_PS_COEF_INDEX_SET(pipe, id, set), 0);
+}
+
+inline u32 skl_scaler_get_filter_select(enum drm_scaling_filter filter, int set)
+{
+ if (filter == DRM_SCALING_FILTER_NEAREST_NEIGHBOR) {
+ return (PS_FILTER_PROGRAMMED |
+ PS_Y_VERT_FILTER_SELECT(set) |
+ PS_Y_HORZ_FILTER_SELECT(set) |
+ PS_UV_VERT_FILTER_SELECT(set) |
+ PS_UV_HORZ_FILTER_SELECT(set));
+ }
+
+ return PS_FILTER_MEDIUM;
+}
+
+void skl_scaler_setup_filter(struct drm_i915_private *dev_priv, enum pipe pipe,
+ int id, int set, enum drm_scaling_filter filter)
+{
+ switch (filter) {
+ case DRM_SCALING_FILTER_DEFAULT:
+ break;
+ case DRM_SCALING_FILTER_NEAREST_NEIGHBOR:
+ cnl_program_nearest_filter_coefs(dev_priv, pipe, id, set);
+ break;
+ default:
+ MISSING_CASE(filter);
+ }
+}
+
static void skl_pfit_enable(const struct intel_crtc_state *crtc_state)
{
struct intel_crtc *crtc = to_intel_crtc(crtc_state->uapi.crtc);
diff --git a/drivers/gpu/drm/i915/display/intel_display.h b/drivers/gpu/drm/i915/display/intel_display.h
index d10b7c8cde3f..1b946209e06b 100644
--- a/drivers/gpu/drm/i915/display/intel_display.h
+++ b/drivers/gpu/drm/i915/display/intel_display.h
@@ -28,6 +28,7 @@
#include <drm/drm_util.h>
enum link_m_n_set;
+enum drm_scaling_filter;
struct dpll;
struct drm_connector;
struct drm_device;
@@ -599,6 +600,9 @@ void intel_crtc_arm_fifo_underrun(struct intel_crtc *crtc,
u16 skl_scaler_calc_phase(int sub, int scale, bool chroma_center);
void skl_scaler_disable(const struct intel_crtc_state *old_crtc_state);
+u32 skl_scaler_get_filter_select(enum drm_scaling_filter filter, int set);
+void skl_scaler_setup_filter(struct drm_i915_private *dev_priv, enum pipe pipe,
+ int id, int set, enum drm_scaling_filter filter);
void ilk_pfit_disable(const struct intel_crtc_state *old_crtc_state);
u32 glk_plane_color_ctl(const struct intel_crtc_state *crtc_state,
const struct intel_plane_state *plane_state);