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From: Krishna Chaitanya Chundru <krishna.chundru@oss.qualcomm.com>
To: Bjorn Andersson <andersson@kernel.org>,
	Konrad Dybcio <konradybcio@kernel.org>,
	Rob Herring <robh@kernel.org>,
	Krzysztof Kozlowski <krzk+dt@kernel.org>,
	Conor Dooley <conor+dt@kernel.org>
Cc: linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org,
	linux-kernel@vger.kernel.org, mani@kernel.org,
	Krishna Chaitanya Chundru <krishna.chundru@oss.qualcomm.com>
Subject: [PATCH 0/8] arm64: dts: qcom: Add t-power-on-us property for PCIe root ports
Date: Fri, 11 Sep 2026 12:20:01 +0530	[thread overview]
Message-ID: <20260911-t_pwr_on-v1-0-c9eee197d082@oss.qualcomm.com> (raw)

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/
[2] https://lore.kernel.org/all/20260428-t_power_on_fux-v5-0-f1ef926a91ff@oss.qualcomm.com/

Signed-off-by: Krishna Chaitanya Chundru <krishna.chundru@oss.qualcomm.com>
---
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@oss.qualcomm.com>


             reply	other threads:[~2026-09-11  6:50 UTC|newest]

Thread overview: 12+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-09-11  6:50 Krishna Chaitanya Chundru [this message]
2026-09-11  6:50 ` [PATCH 1/8] arm64: dts: qcom: kodiak: Add t-power-on-us property for PCIe root ports Krishna Chaitanya Chundru
2026-09-11  6:50 ` [PATCH 2/8] arm64: dts: qcom: lemans: " Krishna Chaitanya Chundru
2026-09-11  7:03   ` sashiko-bot
2026-09-11  6:50 ` [PATCH 3/8] arm64: dts: qcom: monaco: " Krishna Chaitanya Chundru
2026-09-11  7:02   ` sashiko-bot
2026-09-11  6:50 ` [PATCH 4/8] arm64: dts: qcom: hamoa: " Krishna Chaitanya Chundru
2026-09-11  6:50 ` [PATCH 5/8] arm64: dts: qcom: glymur: " Krishna Chaitanya Chundru
2026-09-11  6:50 ` [PATCH 6/8] arm64: dts: qcom: talos: Add t-power-on-us property for PCIe root port Krishna Chaitanya Chundru
2026-09-11  6:50 ` [PATCH 7/8] arm64: dts: qcom: sm8750: " Krishna Chaitanya Chundru
2026-09-11  6:58   ` sashiko-bot
2026-09-11  6:50 ` [PATCH 8/8] arm64: dts: qcom: kaanapali: " Krishna Chaitanya Chundru

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