[PATCH 0/8] Subject: arm64: dts: qcom: Add t-power-on-us property for PCIe root ports
From: Krishna Chaitanya Chundru
Date: Fri Sep 11 2026 - 02:49:27 EST
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@xxxxxxxxxxxxxxxx/
[2] https://lore.kernel.org/all/20260428-t_power_on_fux-v5-0-f1ef926a91ff@xxxxxxxxxxxxxxxx/
Signed-off-by: Krishna Chaitanya Chundru <krishna.chundru@xxxxxxxxxxxxxxxx>
---
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 <krishna.chundru@xxxxxxxxxxxxxxxx>