[PATCH 12/14] drm/i915/dp: Refactor dsc_slice_count handling in intel_dp_mode_valid()

[Ankit Nautiyal <ankit.k.nautiyal@intel.com>]

Make dsc_slice_count closer to the block where it is used and promote it
from u8 to int. This aligns it with upcoming DSC bubble pixel-rate
adjustments, where the slice count participates in wider arithmetic.

Currently, for non-eDP (DP/DP_MST) cases  the slice count is computed only
inside intel_dp_dsc_mode_valid() and is not used by the caller. Once DSC
bubble handling is added, dp_mode_valid() will need access to its own local
slice count for non-eDP cases as well.

Signed-off-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
---
 drivers/gpu/drm/i915/display/intel_dp.c | 13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_dp.c b/drivers/gpu/drm/i915/display/intel_dp.c
index ed81cf4adb9b..9f73a1307b6c 100644
--- a/drivers/gpu/drm/i915/display/intel_dp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp.c
@@ -1464,7 +1464,6 @@ intel_dp_mode_valid(struct drm_connector *_connector,
 	int target_clock = mode->clock;
 	int max_rate, mode_rate, max_lanes, max_link_clock;
 	u16 dsc_max_compressed_bpp = 0;
-	u8 dsc_slice_count = 0;
 	enum drm_mode_status status;
 	bool dsc = false;
 	int num_joined_pipes;
@@ -1508,6 +1507,7 @@ intel_dp_mode_valid(struct drm_connector *_connector,
 
 	for (i = 0; i < ARRAY_SIZE(joiner_candidates); i++) {
 		enum joiner_type joiner = joiner_candidates[i];
+		int dsc_slice_count = 0;
 
 		status = MODE_CLOCK_HIGH;
 
@@ -1534,6 +1534,11 @@ intel_dp_mode_valid(struct drm_connector *_connector,
 		if (intel_dp_has_dsc(connector)) {
 			int pipe_bpp;
 
+			dsc_slice_count = intel_dp_dsc_get_slice_count(connector,
+								       target_clock,
+								       mode->hdisplay,
+								       num_joined_pipes);
+
 			/*
 			 * TBD pass the connector BPC,
 			 * for now U8_MAX so that max BPC on that platform would be picked
@@ -1548,12 +1553,6 @@ intel_dp_mode_valid(struct drm_connector *_connector,
 				dsc_max_compressed_bpp =
 					drm_edp_dsc_sink_output_bpp(connector->dp.dsc_dpcd) >> 4;
 
-				dsc_slice_count =
-					intel_dp_dsc_get_slice_count(connector,
-								     target_clock,
-								     mode->hdisplay,
-								     num_joined_pipes);
-
 				dsc = dsc_max_compressed_bpp && dsc_slice_count;
 			} else if (drm_dp_sink_supports_fec(connector->dp.fec_capability)) {
 				unsigned long bw_overhead_flags = 0;
-- 
2.45.2