drm/i915: Replace to_bpp_int_roundup() with fxp_q4_to_int_roundup()

Replace the to_bpp_int_roundup() helper defined by the driver with the
equivalent fxp_q4_to_int_roundup() helper defined by DRM core.

v2: Rebase on s/drm_x16/fxp_q4 change.
Acked-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Imre Deak <imre.deak@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240805150802.3568970-4-imre.deak@intel.com

drivers/gpu/drm/i915/display/intel_cdclk.c

@@ -23,7 +23,10 @@
 
 #include <linux/time.h>
 
+#include <drm/drm_fixed.h>
+
 #include "soc/intel_dram.h"
+
 #include "hsw_ips.h"
 #include "i915_reg.h"
 #include "intel_atomic.h"
@@ -2750,7 +2753,7 @@ static int intel_vdsc_min_cdclk(const struct intel_crtc_state *crtc_state)
 		 */
 		int bigjoiner_interface_bits = DISPLAY_VER(i915) >= 14 ? 36 : 24;
 		int min_cdclk_bj =
-			(to_bpp_int_roundup(crtc_state->dsc.compressed_bpp_x16) *
+			(fxp_q4_to_int_roundup(crtc_state->dsc.compressed_bpp_x16) *
 			 pixel_clock) / (2 * bigjoiner_interface_bits);
 
 		min_cdclk = max(min_cdclk, min_cdclk_bj);

drivers/gpu/drm/i915/display/intel_display_types.h

@@ -2208,11 +2208,6 @@ static inline int to_bpp_frac(int bpp_x16)
 #define BPP_X16_FMT		"%d.%04d"
 #define BPP_X16_ARGS(bpp_x16)	fxp_q4_to_int(bpp_x16), (to_bpp_frac(bpp_x16) * 625)
 
-static inline int to_bpp_int_roundup(int bpp_x16)
-{
-	return (bpp_x16 + 0xf) >> 4;
-}
-
 /*
  * Conversion functions/macros from various pointer types to struct
  * intel_display pointer.

drivers/gpu/drm/i915/display/intel_dp.c

@@ -2101,7 +2101,7 @@ static int dsc_compute_compressed_bpp(struct intel_dp *intel_dp,
 	dsc_src_min_bpp = dsc_src_min_compressed_bpp();
 	dsc_sink_min_bpp = intel_dp_dsc_sink_min_compressed_bpp(pipe_config);
 	dsc_min_bpp = max(dsc_src_min_bpp, dsc_sink_min_bpp);
-	dsc_min_bpp = max(dsc_min_bpp, to_bpp_int_roundup(limits->link.min_bpp_x16));
+	dsc_min_bpp = max(dsc_min_bpp, fxp_q4_to_int_roundup(limits->link.min_bpp_x16));
 
 	dsc_src_max_bpp = dsc_src_max_compressed_bpp(intel_dp);
 	dsc_sink_max_bpp = intel_dp_dsc_sink_max_compressed_bpp(connector,
@@ -2263,7 +2263,7 @@ static int intel_edp_dsc_compute_pipe_bpp(struct intel_dp *intel_dp,
 	dsc_src_min_bpp = dsc_src_min_compressed_bpp();
 	dsc_sink_min_bpp = intel_dp_dsc_sink_min_compressed_bpp(pipe_config);
 	dsc_min_bpp = max(dsc_src_min_bpp, dsc_sink_min_bpp);
-	dsc_min_bpp = max(dsc_min_bpp, to_bpp_int_roundup(limits->link.min_bpp_x16));
+	dsc_min_bpp = max(dsc_min_bpp, fxp_q4_to_int_roundup(limits->link.min_bpp_x16));
 
 	dsc_src_max_bpp = dsc_src_max_compressed_bpp(intel_dp);
 	dsc_sink_max_bpp = intel_dp_dsc_sink_max_compressed_bpp(connector,
@@ -2489,7 +2489,7 @@ int intel_dp_config_required_rate(const struct intel_crtc_state *crtc_state)
 	const struct drm_display_mode *adjusted_mode =
 		&crtc_state->hw.adjusted_mode;
 	int bpp = crtc_state->dsc.compression_enable ?
-		to_bpp_int_roundup(crtc_state->dsc.compressed_bpp_x16) :
+		fxp_q4_to_int_roundup(crtc_state->dsc.compressed_bpp_x16) :
 		crtc_state->pipe_bpp;
 
 	return intel_dp_link_required(adjusted_mode->crtc_clock, bpp);

drivers/gpu/drm/i915/display/intel_dp_mst.c

@@ -379,7 +379,7 @@ static int intel_dp_dsc_mst_compute_link_config(struct intel_encoder *encoder,
 
 	min_compressed_bpp = intel_dp_dsc_sink_min_compressed_bpp(crtc_state);
 	min_compressed_bpp = max(min_compressed_bpp,
-				 to_bpp_int_roundup(limits->link.min_bpp_x16));
+				 fxp_q4_to_int_roundup(limits->link.min_bpp_x16));
 
 	drm_dbg_kms(&i915->drm, "DSC Sink supported compressed min bpp %d compressed max bpp %d\n",
 		    min_compressed_bpp, max_compressed_bpp);