drm/amd/display: fix k1 k2 divider programming for phantom streams

[ Upstream commit 3b214bb ]

[Why & How]
When k1 and k2 divider programming logic is executed for a phantom
stream, the corresponding master stream should be used for the
calculation. Fix the if condition to use the master stream for checking
signal type instead of the phantom stream.

Reviewed-by: Alvin Lee <Alvin.Lee2@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Aurabindo Pillai <aurabindo.pillai@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Stable-dep-of: 709671f ("drm/amd/display: Remove OTG DIV register write for Virtual signals.")
Signed-off-by: Sasha Levin <sashal@kernel.org>

Author: Aurabindo Pillai

drivers/gpu/drm/amd/display/dc/dcn32/dcn32_hwseq.c

@@ -1174,13 +1174,13 @@ unsigned int dcn32_calculate_dccg_k1_k2_values(struct pipe_ctx *pipe_ctx, unsign
 	if (is_dp_128b_132b_signal(pipe_ctx)) {
 		*k1_div = PIXEL_RATE_DIV_BY_1;
 		*k2_div = PIXEL_RATE_DIV_BY_1;
-	} else if (dc_is_hdmi_tmds_signal(pipe_ctx->stream->signal) || dc_is_dvi_signal(pipe_ctx->stream->signal)) {
+	} else if (dc_is_hdmi_tmds_signal(stream->signal) || dc_is_dvi_signal(stream->signal)) {
 		*k1_div = PIXEL_RATE_DIV_BY_1;
 		if (stream->timing.pixel_encoding == PIXEL_ENCODING_YCBCR420)
 			*k2_div = PIXEL_RATE_DIV_BY_2;
 		else
 			*k2_div = PIXEL_RATE_DIV_BY_4;
-	} else if (dc_is_dp_signal(pipe_ctx->stream->signal) || dc_is_virtual_signal(pipe_ctx->stream->signal)) {
+	} else if (dc_is_dp_signal(stream->signal) || dc_is_virtual_signal(stream->signal)) {
 		if (two_pix_per_container) {
 			*k1_div = PIXEL_RATE_DIV_BY_1;
 			*k2_div = PIXEL_RATE_DIV_BY_2;