[PATCH 0/8] arm64: dts: qcom: Add t-power-on-us property for PCIe root ports
From: Krishna Chaitanya Chundru <hidden>
Date: 2026-09-11 06:50:15
Also in:
linux-arm-msm, lkml
The Qualcomm PCIe host controller driver added support for parsing the -power-on-us property[1] from each Root Port node and programming it as art of host initialization (PCI: qcom: Program T_POWER_ON) [2]. Prior to this, T_POWER_ON was expected to be programmed correctly in hardware or by the bootloader, but not all targets support this, which can lead to an incorrectly calculated LTR_L1.2_THRESHOLD in aspm.c and improper L1.2 exit behavior. This series adds the t-power-on-us = <80>; property to the PCIe root port node(s) on the following targets, so the controller programs the correct T_POWER_ON value instead of relying on the (currently incorrect) hardware default: - kodiak - lemans - monaco - hamoa - glymur - talos - sm8750 - kaanapali [1] https://lore.kernel.org/all/20260205093346.667898-1-krishna.chundru@oss.qualcomm.com/ (local) [2] https://lore.kernel.org/all/20260428-t_power_on_fux-v5-0-f1ef926a91ff@oss.qualcomm.com/ (local) Signed-off-by: Krishna Chaitanya Chundru <redacted> --- Krishna Chaitanya Chundru (8): arm64: dts: qcom: kodiak: Add t-power-on-us property for PCIe root ports arm64: dts: qcom: lemans: Add t-power-on-us property for PCIe root ports arm64: dts: qcom: monaco: Add t-power-on-us property for PCIe root ports arm64: dts: qcom: hamoa: Add t-power-on-us property for PCIe root ports arm64: dts: qcom: glymur: Add t-power-on-us property for PCIe root ports arm64: dts: qcom: talos: Add t-power-on-us property for PCIe root port arm64: dts: qcom: sm8750: Add t-power-on-us property for PCIe root port arm64: dts: qcom: kaanapali: Add t-power-on-us property for PCIe root port arch/arm64/boot/dts/qcom/glymur.dtsi | 8 ++++++++ arch/arm64/boot/dts/qcom/hamoa.dtsi | 8 ++++++++ arch/arm64/boot/dts/qcom/kaanapali.dtsi | 2 ++ arch/arm64/boot/dts/qcom/kodiak.dtsi | 4 ++++ arch/arm64/boot/dts/qcom/lemans.dtsi | 4 ++++ arch/arm64/boot/dts/qcom/monaco.dtsi | 4 ++++ arch/arm64/boot/dts/qcom/sm8750.dtsi | 2 ++ arch/arm64/boot/dts/qcom/talos.dtsi | 2 ++ 8 files changed, 34 insertions(+) --- base-commit: 08df884136f1c1197bab2a27814404fd329d9aac change-id: 20260911-t_pwr_on-069f454ebb23 Best regards, -- Krishna Chaitanya Chundru [off-list ref]