drm/amd/display: Update SW cursor fallback for subvp high refresh

[Description]
Since SubVP high refresh is now enabled, we must
fallback to SW cursor under if we're in a SubVP
high refresh config
Reviewed-by: Samson Tam <samson.tam@amd.com>
Acked-by: Alan Liu <haoping.liu@amd.com>
Signed-off-by: Alvin Lee <alvin.lee2@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drivers/gpu/drm/amd/display/dc/core/dc_stream.c

@@ -306,6 +306,32 @@ bool dc_optimize_timing_for_fsft(
 }
 #endif
 
+static bool is_subvp_high_refresh_candidate(struct dc_stream_state *stream)
+{
+	uint32_t refresh_rate;
+	struct dc *dc = stream->ctx->dc;
+
+	refresh_rate = (stream->timing.pix_clk_100hz * (uint64_t)100 +
+		stream->timing.v_total * stream->timing.h_total - (uint64_t)1);
+	refresh_rate = div_u64(refresh_rate, stream->timing.v_total);
+	refresh_rate = div_u64(refresh_rate, stream->timing.h_total);
+
+	/* If there's any stream that fits the SubVP high refresh criteria,
+	 * we must return true. This is because cursor updates are asynchronous
+	 * with full updates, so we could transition into a SubVP config and
+	 * remain in HW cursor mode if there's no cursor update which will
+	 * then cause corruption.
+	 */
+	if ((refresh_rate >= 120 && refresh_rate <= 165 &&
+			stream->timing.v_addressable >= 1440 &&
+			stream->timing.v_addressable <= 2160) &&
+			(dc->current_state->stream_count > 1 ||
+			(dc->current_state->stream_count == 1 && !stream->allow_freesync)))
+		return true;
+
+	return false;
+}
+
 /*
  * dc_stream_set_cursor_attributes() - Update cursor attributes and set cursor surface address
  */
@@ -334,12 +360,13 @@ bool dc_stream_set_cursor_attributes(
 
 	/* SubVP is not compatible with HW cursor larger than 64 x 64 x 4.
 	 * Therefore, if cursor is greater than 64 x 64 x 4, fallback to SW cursor in the following case:
-	 * 1. For single display cases, if resolution is >= 5K and refresh rate < 120hz
-	 * 2. For multi display cases, if resolution is >= 4K and refresh rate < 120hz
-	 *
-	 * [< 120hz is a requirement for SubVP configs]
+	 * 1. If the config is a candidate for SubVP high refresh (both single an dual display configs)
+	 * 2. If not subvp high refresh, for single display cases, if resolution is >= 5K and refresh rate < 120hz
+	 * 3. If not subvp high refresh, for multi display cases, if resolution is >= 4K and refresh rate < 120hz
 	 */
 	if (dc->debug.allow_sw_cursor_fallback && attributes->height * attributes->width * 4 > 16384) {
+		if (!dc->debug.disable_subvp_high_refresh && is_subvp_high_refresh_candidate(stream))
+			return false;
 		if (dc->current_state->stream_count == 1 && stream->timing.v_addressable >= 2880 &&
 				((stream->timing.pix_clk_100hz * 100) / stream->timing.v_total / stream->timing.h_total) < 120)
 			return false;