[PATCH 13/19] drm/amd/display: Add minimum vfp requirement

[Chenyu Chen <chen-yu.chen@amd.com>]

From: Dillon Varone <Dillon.Varone@amd.com>

[WHY&HOW]
Vertical front porch (vfp) must be greater than 1, and must be patched
if it isn't.  This must be done pre-DML so the DLG programming remains
consistent with the OTG programming.

Reviewed-by: Austin Zheng <austin.zheng@amd.com>
Signed-off-by: Dillon Varone <Dillon.Varone@amd.com>
Signed-off-by: Chenyu Chen <chen-yu.chen@amd.com>
---
 .../amd/display/dc/dml2_0/dml21/dml21_translation_helper.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/amd/display/dc/dml2_0/dml21/dml21_translation_helper.c b/drivers/gpu/drm/amd/display/dc/dml2_0/dml21/dml21_translation_helper.c
index 476030193f14..9031fd582ec7 100644
--- a/drivers/gpu/drm/amd/display/dc/dml2_0/dml21/dml21_translation_helper.c
+++ b/drivers/gpu/drm/amd/display/dc/dml2_0/dml21/dml21_translation_helper.c
@@ -90,6 +90,8 @@ static void populate_dml21_timing_config_from_stream_state(struct dml2_timing_cf
 		struct pipe_ctx *pipe_ctx,
 		struct dml2_context *dml_ctx)
 {
+	const unsigned int min_v_front_porch = (stream->timing.flags.INTERLACE != 0) ? 2 : 1;
+
 	unsigned int hblank_start, vblank_start;
 	uint64_t min_hardware_refresh_in_uhz;
 	uint32_t pix_clk_100hz;
@@ -97,7 +99,8 @@ static void populate_dml21_timing_config_from_stream_state(struct dml2_timing_cf
 	timing->h_active = stream->timing.h_addressable + stream->timing.h_border_left + stream->timing.h_border_right + pipe_ctx->dsc_padding_params.dsc_hactive_padding;
 	timing->v_active = stream->timing.v_addressable + stream->timing.v_border_bottom + stream->timing.v_border_top;
 	timing->h_front_porch = stream->timing.h_front_porch;
-	timing->v_front_porch = stream->timing.v_front_porch;
+	timing->v_front_porch = stream->timing.v_front_porch > min_v_front_porch ?
+			stream->timing.v_front_porch : min_v_front_porch;
 	timing->pixel_clock_khz = stream->timing.pix_clk_100hz / 10;
 	if (pipe_ctx->dsc_padding_params.dsc_hactive_padding != 0)
 		timing->pixel_clock_khz = pipe_ctx->dsc_padding_params.dsc_pix_clk_100hz / 10;
@@ -116,7 +119,7 @@ static void populate_dml21_timing_config_from_stream_state(struct dml2_timing_cf
 	if (hblank_start < stream->timing.h_addressable)
 		timing->h_blank_end = 0;
 
-	vblank_start = stream->timing.v_total - stream->timing.v_front_porch;
+	vblank_start = timing->v_total - timing->v_front_porch;
 
 	timing->v_blank_end = vblank_start - stream->timing.v_addressable
 		- stream->timing.v_border_top - stream->timing.v_border_bottom;
-- 
2.43.0