From 7d43ed29844f8858cd8e0855cc4c5240cdd0e15c Mon Sep 17 00:00:00 2001 From: Anthony Koo Date: Thu, 15 Mar 2018 14:54:30 -0400 Subject: [PATCH 3948/4131] drm/amd/display: Only program MSA_TIMING_PARAM if it changed Signed-off-by: Harry Wentland Reviewed-by: Harry Wentland --- drivers/gpu/drm/amd/display/dc/core/dc_link.c | 15 ++++++++++----- 1 file changed, 10 insertions(+), 5 deletions(-) diff --git a/drivers/gpu/drm/amd/display/dc/core/dc_link.c b/drivers/gpu/drm/amd/display/dc/core/dc_link.c index 65f2ce9b..e612841 100644 --- a/drivers/gpu/drm/amd/display/dc/core/dc_link.c +++ b/drivers/gpu/drm/amd/display/dc/core/dc_link.c @@ -1183,16 +1183,21 @@ static void enable_stream_features(struct pipe_ctx *pipe_ctx) { struct dc_stream_state *stream = pipe_ctx->stream; struct dc_link *link = stream->sink->link; - union down_spread_ctrl downspread; + union down_spread_ctrl old_downspread; + union down_spread_ctrl new_downspread; core_link_read_dpcd(link, DP_DOWNSPREAD_CTRL, - &downspread.raw, sizeof(downspread)); + &old_downspread.raw, sizeof(old_downspread)); - downspread.bits.IGNORE_MSA_TIMING_PARAM = + new_downspread.raw = old_downspread.raw; + + new_downspread.bits.IGNORE_MSA_TIMING_PARAM = (stream->ignore_msa_timing_param) ? 1 : 0; - core_link_write_dpcd(link, DP_DOWNSPREAD_CTRL, - &downspread.raw, sizeof(downspread)); + if (new_downspread.raw != old_downspread.raw) { + core_link_write_dpcd(link, DP_DOWNSPREAD_CTRL, + &new_downspread.raw, sizeof(new_downspread)); + } } static enum dc_status enable_link_dp( -- 2.7.4