[Intel-gfx] [PATCH 2/8] drm/i915/display: Store compressed bpp in U6.4 format

Mitul Golani mitulkumar.ajitkumar.golani at intel.com
Mon Sep 11 05:05:43 UTC 2023


From: Ankit Nautiyal <ankit.k.nautiyal at intel.com>

DSC parameter bits_per_pixel is stored in U6.4 format.
The 4 bits represent the fractional part of the bpp.
Currently we use compressed_bpp member of dsc structure to store
only the integral part of the bits_per_pixel.
To store the full bits_per_pixel along with the fractional part,
compressed_bpp is changed to store bpp in U6.4 formats. Intergral
part is retrieved by simply right shifting the member compressed_bpp by 4.

v2:
-Use to_bpp_int, to_bpp_frac_dec, to_bpp_x16 helpers while dealing
 with compressed bpp. (Suraj)
-Fix comment styling. (Suraj)

Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal at intel.com>
---
 drivers/gpu/drm/i915/display/icl_dsi.c        | 10 ++++----
 drivers/gpu/drm/i915/display/intel_audio.c    |  2 +-
 drivers/gpu/drm/i915/display/intel_bios.c     |  4 +--
 drivers/gpu/drm/i915/display/intel_cdclk.c    |  2 +-
 drivers/gpu/drm/i915/display/intel_display.c  |  2 +-
 .../drm/i915/display/intel_display_types.h    | 18 ++++++++++++-
 drivers/gpu/drm/i915/display/intel_dp.c       | 25 +++++++++++--------
 drivers/gpu/drm/i915/display/intel_dp_mst.c   | 18 ++++++-------
 drivers/gpu/drm/i915/display/intel_vdsc.c     |  4 +--
 9 files changed, 52 insertions(+), 33 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/icl_dsi.c b/drivers/gpu/drm/i915/display/icl_dsi.c
index ad6488e9c2b2..df98f35bbcda 100644
--- a/drivers/gpu/drm/i915/display/icl_dsi.c
+++ b/drivers/gpu/drm/i915/display/icl_dsi.c
@@ -330,7 +330,7 @@ static int afe_clk(struct intel_encoder *encoder,
 	int bpp;
 
 	if (crtc_state->dsc.compression_enable)
-		bpp = crtc_state->dsc.compressed_bpp;
+		bpp = to_bpp_int(crtc_state->dsc.compressed_bpp_x16);
 	else
 		bpp = mipi_dsi_pixel_format_to_bpp(intel_dsi->pixel_format);
 
@@ -860,7 +860,7 @@ gen11_dsi_set_transcoder_timings(struct intel_encoder *encoder,
 	 * compressed and non-compressed bpp.
 	 */
 	if (crtc_state->dsc.compression_enable) {
-		mul = crtc_state->dsc.compressed_bpp;
+		mul = to_bpp_int(crtc_state->dsc.compressed_bpp_x16);
 		div = mipi_dsi_pixel_format_to_bpp(intel_dsi->pixel_format);
 	}
 
@@ -884,7 +884,7 @@ gen11_dsi_set_transcoder_timings(struct intel_encoder *encoder,
 		int bpp, line_time_us, byte_clk_period_ns;
 
 		if (crtc_state->dsc.compression_enable)
-			bpp = crtc_state->dsc.compressed_bpp;
+			bpp = to_bpp_int(crtc_state->dsc.compressed_bpp_x16);
 		else
 			bpp = mipi_dsi_pixel_format_to_bpp(intel_dsi->pixel_format);
 
@@ -1451,8 +1451,8 @@ static void gen11_dsi_get_timings(struct intel_encoder *encoder,
 	struct drm_display_mode *adjusted_mode =
 					&pipe_config->hw.adjusted_mode;
 
-	if (pipe_config->dsc.compressed_bpp) {
-		int div = pipe_config->dsc.compressed_bpp;
+	if (pipe_config->dsc.compressed_bpp_x16) {
+		int div = to_bpp_int(pipe_config->dsc.compressed_bpp_x16);
 		int mul = mipi_dsi_pixel_format_to_bpp(intel_dsi->pixel_format);
 
 		adjusted_mode->crtc_htotal =
diff --git a/drivers/gpu/drm/i915/display/intel_audio.c b/drivers/gpu/drm/i915/display/intel_audio.c
index 19605264a35c..aa93ccd6c2aa 100644
--- a/drivers/gpu/drm/i915/display/intel_audio.c
+++ b/drivers/gpu/drm/i915/display/intel_audio.c
@@ -528,7 +528,7 @@ static unsigned int calc_hblank_early_prog(struct intel_encoder *encoder,
 	h_active = crtc_state->hw.adjusted_mode.crtc_hdisplay;
 	h_total = crtc_state->hw.adjusted_mode.crtc_htotal;
 	pixel_clk = crtc_state->hw.adjusted_mode.crtc_clock;
-	vdsc_bpp = crtc_state->dsc.compressed_bpp;
+	vdsc_bpp = to_bpp_int(crtc_state->dsc.compressed_bpp_x16);
 	cdclk = i915->display.cdclk.hw.cdclk;
 	/* fec= 0.972261, using rounding multiplier of 1000000 */
 	fec_coeff = 972261;
diff --git a/drivers/gpu/drm/i915/display/intel_bios.c b/drivers/gpu/drm/i915/display/intel_bios.c
index 858c959f7bab..7b6d299fbcf2 100644
--- a/drivers/gpu/drm/i915/display/intel_bios.c
+++ b/drivers/gpu/drm/i915/display/intel_bios.c
@@ -3384,8 +3384,8 @@ static void fill_dsc(struct intel_crtc_state *crtc_state,
 
 	crtc_state->pipe_bpp = bpc * 3;
 
-	crtc_state->dsc.compressed_bpp = min(crtc_state->pipe_bpp,
-					     VBT_DSC_MAX_BPP(dsc->max_bpp));
+	crtc_state->dsc.compressed_bpp_x16 = to_bpp_x16(min(crtc_state->pipe_bpp,
+							    VBT_DSC_MAX_BPP(dsc->max_bpp)));
 
 	/*
 	 * FIXME: This is ugly, and slice count should take DSC engine
diff --git a/drivers/gpu/drm/i915/display/intel_cdclk.c b/drivers/gpu/drm/i915/display/intel_cdclk.c
index ad5251ba6fe1..06a1e99a2762 100644
--- a/drivers/gpu/drm/i915/display/intel_cdclk.c
+++ b/drivers/gpu/drm/i915/display/intel_cdclk.c
@@ -2567,7 +2567,7 @@ static int intel_vdsc_min_cdclk(const struct intel_crtc_state *crtc_state)
 		 * => CDCLK >= compressed_bpp * Pixel clock  / 2 * Bigjoiner Interface bits
 		 */
 		int bigjoiner_interface_bits = DISPLAY_VER(i915) > 13 ? 36 : 24;
-		int min_cdclk_bj = (crtc_state->dsc.compressed_bpp * pixel_clock) /
+		int min_cdclk_bj = (to_bpp_int(crtc_state->dsc.compressed_bpp_x16) * pixel_clock) /
 				   (2 * bigjoiner_interface_bits);
 
 		min_cdclk = max(min_cdclk, min_cdclk_bj);
diff --git a/drivers/gpu/drm/i915/display/intel_display.c b/drivers/gpu/drm/i915/display/intel_display.c
index 83e1bc858b9f..afcbdd4f105a 100644
--- a/drivers/gpu/drm/i915/display/intel_display.c
+++ b/drivers/gpu/drm/i915/display/intel_display.c
@@ -5365,7 +5365,7 @@ intel_pipe_config_compare(const struct intel_crtc_state *current_config,
 
 	PIPE_CONF_CHECK_I(dsc.compression_enable);
 	PIPE_CONF_CHECK_I(dsc.dsc_split);
-	PIPE_CONF_CHECK_I(dsc.compressed_bpp);
+	PIPE_CONF_CHECK_I(dsc.compressed_bpp_x16);
 
 	PIPE_CONF_CHECK_BOOL(splitter.enable);
 	PIPE_CONF_CHECK_I(splitter.link_count);
diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
index c21064794f32..9eb7b8912076 100644
--- a/drivers/gpu/drm/i915/display/intel_display_types.h
+++ b/drivers/gpu/drm/i915/display/intel_display_types.h
@@ -1353,7 +1353,8 @@ struct intel_crtc_state {
 	struct {
 		bool compression_enable;
 		bool dsc_split;
-		u16 compressed_bpp;
+		/* Compressed Bpp in U6.4 format (first 4 bits for fractional part) */
+		u16 compressed_bpp_x16;
 		u8 slice_count;
 		struct drm_dsc_config config;
 	} dsc;
@@ -2108,4 +2109,19 @@ to_intel_frontbuffer(struct drm_framebuffer *fb)
 	return fb ? to_intel_framebuffer(fb)->frontbuffer : NULL;
 }
 
+static inline int to_bpp_int(int bpp_x16)
+{
+	return bpp_x16 >> 4;
+}
+
+static inline int to_bpp_frac_dec(int bpp_x16)
+{
+	return (bpp_x16 & 0xf) * 625;
+}
+
+static inline int to_bpp_x16(int bpp)
+{
+	return bpp << 4;
+}
+
 #endif /*  __INTEL_DISPLAY_TYPES_H__ */
diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index 2206b45bc78c..9b88ac3a73c7 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -1863,7 +1863,7 @@ icl_dsc_compute_link_config(struct intel_dp *intel_dp,
 					      valid_dsc_bpp[i],
 					      timeslots);
 		if (ret == 0) {
-			pipe_config->dsc.compressed_bpp = valid_dsc_bpp[i];
+			pipe_config->dsc.compressed_bpp_x16 = to_bpp_x16(valid_dsc_bpp[i]);
 			return 0;
 		}
 	}
@@ -1901,7 +1901,7 @@ xelpd_dsc_compute_link_config(struct intel_dp *intel_dp,
 					      compressed_bpp,
 					      timeslots);
 		if (ret == 0) {
-			pipe_config->dsc.compressed_bpp = compressed_bpp;
+			pipe_config->dsc.compressed_bpp_x16 = to_bpp_x16(compressed_bpp);
 			return 0;
 		}
 	}
@@ -2085,7 +2085,7 @@ static int intel_edp_dsc_compute_pipe_bpp(struct intel_dp *intel_dp,
 	/* Compressed BPP should be less than the Input DSC bpp */
 	dsc_max_bpp = min(dsc_max_bpp, pipe_bpp - 1);
 
-	pipe_config->dsc.compressed_bpp = max(dsc_min_bpp, dsc_max_bpp);
+	pipe_config->dsc.compressed_bpp_x16 = to_bpp_x16(max(dsc_min_bpp, dsc_max_bpp));
 
 	pipe_config->pipe_bpp = pipe_bpp;
 
@@ -2172,17 +2172,19 @@ int intel_dp_dsc_compute_config(struct intel_dp *intel_dp,
 	if (ret < 0) {
 		drm_dbg_kms(&dev_priv->drm,
 			    "Cannot compute valid DSC parameters for Input Bpp = %d "
-			    "Compressed BPP = %d\n",
+			    "Compressed BPP = %d.%d\n",
 			    pipe_config->pipe_bpp,
-			    pipe_config->dsc.compressed_bpp);
+			    to_bpp_int(pipe_config->dsc.compressed_bpp_x16),
+			    to_bpp_frac_dec(pipe_config->dsc.compressed_bpp_x16));
 		return ret;
 	}
 
 	pipe_config->dsc.compression_enable = true;
 	drm_dbg_kms(&dev_priv->drm, "DP DSC computed with Input Bpp = %d "
-		    "Compressed Bpp = %d Slice Count = %d\n",
+		    "Compressed Bpp = %d.%d Slice Count = %d\n",
 		    pipe_config->pipe_bpp,
-		    pipe_config->dsc.compressed_bpp,
+		    to_bpp_int(pipe_config->dsc.compressed_bpp_x16),
+		    to_bpp_frac_dec(pipe_config->dsc.compressed_bpp_x16),
 		    pipe_config->dsc.slice_count);
 
 	return 0;
@@ -2261,15 +2263,16 @@ intel_dp_compute_link_config(struct intel_encoder *encoder,
 
 	if (pipe_config->dsc.compression_enable) {
 		drm_dbg_kms(&i915->drm,
-			    "DP lane count %d clock %d Input bpp %d Compressed bpp %d\n",
+			    "DP lane count %d clock %d Input bpp %d Compressed bpp %d.%d\n",
 			    pipe_config->lane_count, pipe_config->port_clock,
 			    pipe_config->pipe_bpp,
-			    pipe_config->dsc.compressed_bpp);
+			    to_bpp_int(pipe_config->dsc.compressed_bpp_x16),
+			    to_bpp_frac_dec(pipe_config->dsc.compressed_bpp_x16));
 
 		drm_dbg_kms(&i915->drm,
 			    "DP link rate required %i available %i\n",
 			    intel_dp_link_required(adjusted_mode->crtc_clock,
-						   pipe_config->dsc.compressed_bpp),
+						   to_bpp_int(pipe_config->dsc.compressed_bpp_x16)),
 			    intel_dp_max_data_rate(pipe_config->port_clock,
 						   pipe_config->lane_count));
 	} else {
@@ -2702,7 +2705,7 @@ intel_dp_compute_config(struct intel_encoder *encoder,
 		intel_dp_limited_color_range(pipe_config, conn_state);
 
 	if (pipe_config->dsc.compression_enable)
-		link_bpp = pipe_config->dsc.compressed_bpp;
+		link_bpp = pipe_config->dsc.compressed_bpp_x16;
 	else
 		link_bpp = intel_dp_output_bpp(pipe_config->output_format,
 					       pipe_config->pipe_bpp);
diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
index 2d1c42a5e684..68a81f10e772 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
@@ -140,7 +140,7 @@ static int intel_dp_mst_find_vcpi_slots_for_bpp(struct intel_encoder *encoder,
 		if (!dsc)
 			crtc_state->pipe_bpp = bpp;
 		else
-			crtc_state->dsc.compressed_bpp = bpp;
+			crtc_state->dsc.compressed_bpp_x16 = to_bpp_x16(bpp);
 		drm_dbg_kms(&i915->drm, "Got %d slots for pipe bpp %d dsc %d\n", slots, bpp, dsc);
 	}
 
@@ -238,13 +238,13 @@ static int intel_dp_dsc_mst_compute_link_config(struct intel_encoder *encoder,
 	if (slots < 0)
 		return slots;
 
-	last_compressed_bpp = crtc_state->dsc.compressed_bpp;
+	last_compressed_bpp = to_bpp_int(crtc_state->dsc.compressed_bpp_x16);
 
-	crtc_state->dsc.compressed_bpp = intel_dp_dsc_nearest_valid_bpp(i915,
-									last_compressed_bpp,
-									crtc_state->pipe_bpp);
+	crtc_state->dsc.compressed_bpp_x16 =
+				to_bpp_x16(intel_dp_dsc_nearest_valid_bpp(i915, last_compressed_bpp,
+									  crtc_state->pipe_bpp));
 
-	if (crtc_state->dsc.compressed_bpp != last_compressed_bpp)
+	if (crtc_state->dsc.compressed_bpp_x16 != to_bpp_x16(last_compressed_bpp))
 		need_timeslot_recalc = true;
 
 	/*
@@ -253,14 +253,14 @@ static int intel_dp_dsc_mst_compute_link_config(struct intel_encoder *encoder,
 	 */
 	if (need_timeslot_recalc) {
 		slots = intel_dp_mst_find_vcpi_slots_for_bpp(encoder, crtc_state,
-							     crtc_state->dsc.compressed_bpp,
-							     crtc_state->dsc.compressed_bpp,
+							     to_bpp_int(crtc_state->dsc.compressed_bpp_x16),
+							     to_bpp_int(crtc_state->dsc.compressed_bpp_x16),
 							     limits, conn_state, 2 * 3, true);
 		if (slots < 0)
 			return slots;
 	}
 
-	intel_link_compute_m_n(crtc_state->dsc.compressed_bpp,
+	intel_link_compute_m_n(to_bpp_int(crtc_state->dsc.compressed_bpp_x16),
 			       crtc_state->lane_count,
 			       adjusted_mode->crtc_clock,
 			       crtc_state->port_clock,
diff --git a/drivers/gpu/drm/i915/display/intel_vdsc.c b/drivers/gpu/drm/i915/display/intel_vdsc.c
index b24601d0b2c5..bfc41972a0bb 100644
--- a/drivers/gpu/drm/i915/display/intel_vdsc.c
+++ b/drivers/gpu/drm/i915/display/intel_vdsc.c
@@ -248,7 +248,7 @@ int intel_dsc_compute_params(struct intel_crtc_state *pipe_config)
 	struct intel_crtc *crtc = to_intel_crtc(pipe_config->uapi.crtc);
 	struct drm_i915_private *dev_priv = to_i915(crtc->base.dev);
 	struct drm_dsc_config *vdsc_cfg = &pipe_config->dsc.config;
-	u16 compressed_bpp = pipe_config->dsc.compressed_bpp;
+	u16 compressed_bpp = to_bpp_int(pipe_config->dsc.compressed_bpp_x16);
 	int err;
 	int ret;
 
@@ -878,7 +878,7 @@ static void intel_dsc_get_pps_config(struct intel_crtc_state *crtc_state)
 	if (vdsc_cfg->native_420)
 		vdsc_cfg->bits_per_pixel >>= 1;
 
-	crtc_state->dsc.compressed_bpp = vdsc_cfg->bits_per_pixel >> 4;
+	crtc_state->dsc.compressed_bpp_x16 = vdsc_cfg->bits_per_pixel;
 
 	/* PPS_2 */
 	intel_dsc_read_and_verify_pps_reg(crtc_state, 2, &pps_temp);
-- 
2.25.1



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