Received-SPF: pass (google.com: domain of linux-kernel+bounces-33290-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:45e3:2400::1 as permitted sender) client-ip=2604:1380:45e3:2400::1;
From: Sasha Levin <sashal@kernel.org>
To: linux-kernel@vger.kernel.org,
	stable@vger.kernel.org
Cc: Michael Strauss <michael.strauss@amd.com>,
	Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>,
	Charlene Liu <charlene.liu@amd.com>,
	Wayne Lin <wayne.lin@amd.com>,
	Daniel Wheeler <daniel.wheeler@amd.com>,
	Alex Deucher <alexander.deucher@amd.com>,
	Sasha Levin <sashal@kernel.org>,
	harry.wentland@amd.com,
	sunpeng.li@amd.com,
	Rodrigo.Siqueira@amd.com,
	christian.koenig@amd.com,
	Xinhui.Pan@amd.com,
	airlied@gmail.com,
	daniel@ffwll.ch,
	Qingqing.Zhuo@amd.com,
	sungkim@amd.com,
	syed.hassan@amd.com,
	gabe.teeger@amd.com,
	dillon.varone@amd.com,
	amd-gfx@lists.freedesktop.org,
	dri-devel@lists.freedesktop.org
Subject: [PATCH AUTOSEL 6.7 68/88] drm/amd/display: Fix lightup regression with DP2 single display configs
Date: Mon, 22 Jan 2024 09:51:41 -0500
Message-ID: <20240122145608.990137-68-sashal@kernel.org>
In-Reply-To: <20240122145608.990137-1-sashal@kernel.org>
References: <20240122145608.990137-1-sashal@kernel.org>
Precedence: bulk
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit

From: Michael Strauss <michael.strauss@amd.com>

[ Upstream commit 5a82b8d6c05f9b30828ede1b103b9ee5cb5c912e ]

[WHY]
Previous fix for multiple displays downstream of DP2 MST hub caused regression

[HOW]
Match sink IDs instead of sink struct addresses

Reviewed-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Reviewed-by: Charlene Liu <charlene.liu@amd.com>
Acked-by: Wayne Lin <wayne.lin@amd.com>
Signed-off-by: Michael Strauss <michael.strauss@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 drivers/gpu/drm/amd/display/dc/dml2/dml2_utils.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/drivers/gpu/drm/amd/display/dc/dml2/dml2_utils.c b/drivers/gpu/drm/amd/display/dc/dml2/dml2_utils.c
index 2498b8341199..d6a68484153c 100644
--- a/drivers/gpu/drm/amd/display/dc/dml2/dml2_utils.c
+++ b/drivers/gpu/drm/amd/display/dc/dml2/dml2_utils.c
@@ -157,6 +157,14 @@ bool is_dp2p0_output_encoder(const struct pipe_ctx *pipe_ctx)
 {
 	/* If this assert is hit then we have a link encoder dynamic management issue */
 	ASSERT(pipe_ctx->stream_res.hpo_dp_stream_enc ? pipe_ctx->link_res.hpo_dp_link_enc != NULL : true);
+	/* Count MST hubs once by treating only 1st remote sink in topology as an encoder */
+	if (pipe_ctx->stream->link && pipe_ctx->stream->link->remote_sinks[0]) {
+		return (pipe_ctx->stream_res.hpo_dp_stream_enc &&
+			pipe_ctx->link_res.hpo_dp_link_enc &&
+			dc_is_dp_signal(pipe_ctx->stream->signal) &&
+			(pipe_ctx->stream->link->remote_sinks[0]->sink_id == pipe_ctx->stream->sink->sink_id));
+	}
+
 	return (pipe_ctx->stream_res.hpo_dp_stream_enc &&
 		pipe_ctx->link_res.hpo_dp_link_enc &&
 		dc_is_dp_signal(pipe_ctx->stream->signal));
-- 
2.43.0