From: Stephan Gerhold Date: Mon, 15 Sep 2025 13:28:31 +0000 (+0200) Subject: arm64: dts: qcom: msm8939: Add missing MDSS reset X-Git-Tag: v6.12.54~190 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=1e137c4b12b753fffe4b147c3773d8b9f58c1c89;p=thirdparty%2Fkernel%2Fstable.git arm64: dts: qcom: msm8939: Add missing MDSS reset commit f73c82c855e186e9b67125e3eee743960320e43c upstream. On most MSM8939 devices, the bootloader already initializes the display to show the boot splash screen. In this situation, MDSS is already configured and left running when starting Linux. To avoid side effects from the bootloader configuration, the MDSS reset can be specified in the device tree to start again with a clean hardware state. The reset for MDSS is currently missing in msm8939.dtsi, which causes errors when the MDSS driver tries to re-initialize the registers: dsi_err_worker: status=6 dsi_err_worker: status=6 dsi_err_worker: status=6 ... It turns out that we have always indirectly worked around this by building the MDSS driver as a module. Before v6.17, the power domain was temporarily turned off until the module was loaded, long enough to clear the register contents. In v6.17, power domains are not turned off during boot until sync_state() happens, so this is no longer working. Even before v6.17 this resulted in broken behavior, but notably only when the MDSS driver was built-in instead of a module. Cc: stable@vger.kernel.org Fixes: 61550c6c156c ("arm64: dts: qcom: Add msm8939 SoC") Signed-off-by: Stephan Gerhold Reviewed-by: Dmitry Baryshkov Reviewed-by: Konrad Dybcio Link: https://lore.kernel.org/r/20250915-msm8916-resets-v1-2-a5c705df0c45@linaro.org Signed-off-by: Bjorn Andersson Signed-off-by: Greg Kroah-Hartman --- diff --git a/arch/arm64/boot/dts/qcom/msm8939.dtsi b/arch/arm64/boot/dts/qcom/msm8939.dtsi index effa3aaeb2505..39493f75c0dce 100644 --- a/arch/arm64/boot/dts/qcom/msm8939.dtsi +++ b/arch/arm64/boot/dts/qcom/msm8939.dtsi @@ -1218,6 +1218,8 @@ power-domains = <&gcc MDSS_GDSC>; + resets = <&gcc GCC_MDSS_BCR>; + #address-cells = <1>; #size-cells = <1>; #interrupt-cells = <1>;