From cb5b414a156da1c274b891a0b5559089063d56c1 Mon Sep 17 00:00:00 2001 From: Dmitry Baryshkov Date: Sat, 26 Oct 2024 20:59:40 +0300 Subject: [PATCH] arm64: dts: qcom: sm8550: correct MDSS interconnects BugLink: https://bugs.launchpad.net/bugs/2114239 commit b8591df49cde459e3b84cdc0517d7bf92053d244 upstream. SM8550 lists two interconnects for the display subsystem, mdp0-mem (between MDP and LLCC) and mdp1-mem (between LLCC and EBI, memory). The second interconnect is a misuse. mdpN-mem paths should be used for several outboud MDP interconnects rather than the path between LLCC and memory. This kind of misuse can result in bandwidth underflows, possibly degrading picture quality as the required memory bandwidth is divided between all mdpN-mem paths (and LLCC-EBI should not be a part of such division). Drop the second path and use direct MDP-EBI path for mdp0-mem until we support separate MDP-LLCC and LLCC-EBI paths. Fixes: d7da51db5b81 ("arm64: dts: qcom: sm8550: add display hardware devices") Cc: stable@kernel.org Signed-off-by: Dmitry Baryshkov Reviewed-by: Konrad Dybcio Link: https://lore.kernel.org/r/20241026-fix-sm8x50-mdp-icc-v2-1-fd8ddf755acc@linaro.org Signed-off-by: Bjorn Andersson Signed-off-by: Greg Kroah-Hartman Signed-off-by: Noah Wager Signed-off-by: Mehmet Basaran --- arch/arm64/boot/dts/qcom/sm8550.dtsi | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/arch/arm64/boot/dts/qcom/sm8550.dtsi b/arch/arm64/boot/dts/qcom/sm8550.dtsi index a3309c27569c..d999e1179ec8 100644 --- a/arch/arm64/boot/dts/qcom/sm8550.dtsi +++ b/arch/arm64/boot/dts/qcom/sm8550.dtsi @@ -2810,9 +2810,8 @@ power-domains = <&dispcc MDSS_GDSC>; - interconnects = <&mmss_noc MASTER_MDP 0 &gem_noc SLAVE_LLCC 0>, - <&mc_virt MASTER_LLCC 0 &mc_virt SLAVE_EBI1 0>; - interconnect-names = "mdp0-mem", "mdp1-mem"; + interconnects = <&mmss_noc MASTER_MDP 0 &mc_virt SLAVE_EBI1 0>; + interconnect-names = "mdp0-mem"; iommus = <&apps_smmu 0x1c00 0x2>;