drm/amd/display: Allow asic specific FSFT timing optimization

[Why]
Each asic can optimize best based on its capabilities

[How]
Optimizing timing for a new pixel clock

Signed-off-by: Reza Amini <Reza.Amini@amd.com>
Reviewed-by: Anthony Koo <Anthony.Koo@amd.com>
Acked-by: Eryk Brol <eryk.brol@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

1 files changed, 27 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c
index 7725a406c16e..66180b4332f1 100644
--- a/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c
+++ b/drivers/gpu/drm/amd/display/dc/dcn20/dcn20_hwseq.c
@@ -2498,3 +2498,30 @@ void dcn20_fpga_init_hw(struct dc *dc)
 		tg->funcs->tg_init(tg);
 	}
 }
+#ifndef TRIM_FSFT
+bool dcn20_optimize_timing_for_fsft(struct dc *dc,
+		struct dc_crtc_timing *timing,
+		unsigned int max_input_rate_in_khz)
+{
+	unsigned int old_v_front_porch;
+	unsigned int old_v_total;
+	unsigned int max_input_rate_in_100hz;
+	unsigned long long new_v_total;
+
+	max_input_rate_in_100hz = max_input_rate_in_khz * 10;
+	if (max_input_rate_in_100hz < timing->pix_clk_100hz)
+		return false;
+
+	old_v_total = timing->v_total;
+	old_v_front_porch = timing->v_front_porch;
+
+	timing->fast_transport_output_rate_100hz = timing->pix_clk_100hz;
+	timing->pix_clk_100hz = max_input_rate_in_100hz;
+
+	new_v_total = div_u64((unsigned long long)old_v_total * max_input_rate_in_100hz, timing->pix_clk_100hz);
+
+	timing->v_total = new_v_total;
+	timing->v_front_porch = old_v_front_porch + (timing->v_total - old_v_total);
+	return true;
+}
+#endif