Subject: [PATCH v3 00/17] arm64: Use EL2 virtual timer when running VHE

From: Marc Zyngier <[email-masked]>
Date: Sat, 23 May 2026 15:02:25 +0100

This is the third version of the series initially posted at [1],
which

- updates the ACPI GTDT parsing to deal the v3 layout and the EL2
  virtual timer,
- moves the architected timer driver to use it when running VHE,
- fixes a number of DTs to reflect the reality of the HW.

This results in significant performance uplift in deeper nested virt
scenarios, at no overhead to the host.

Patches based on -rc3, tested on Amlogic SM1, QC X1E, Ampere Altra,
and Apple M2, as well as KVM NV guests.

* From v2 [2]:

  - Add more consistency checks to the GTDT parsing

  - Match the virtual counter when using the KVM PTP backend

  - Drop a number of changes to Qualcomm DTs, being only tangentially
    related and that will be posted separately

  - Fix the Realtek Kent platform, which had the GICv3 maintenance
    interrupt advertised as the EL2 virtual timer

  - Collected TBs and RBs, with thanks

* From v1 [2]:

  - Now also using the EL2 virtual counter, which further improve
    things when running at a deeper nesting level

  - Updated consistency checks for the platform timers when finding a
    GTDTv3

  - Collected ABs and RBs, with thanks

[1] https://lore.kernel.org/r/[email-masked]
[2] https://lore.kernel.org/r/[email-masked]

Marc Zyngier (17):
  ACPI: GTDT: Account for GTDTv3 size when walking the platform timer
    descriptors
  ACPI: GTDT: Parse information related to the EL2 virtual timer
  clocksource/drivers/arm_arch_timer: Default to EL2 virtual timer when
    running VHE
  dt-bindings: timer: arm,arch_timer: Fix requirements for interrupt
    description
  arm64: dts: allwinner: Add EL2 virtual timer interrupt
  arm64: dts: amlogic: Add EL2 virtual timer interrupt
  arm64: dts: bst: Add EL2 virtual timer interrupt
  arm64: dts: exynos: Add EL2 virtual timer interrupt
  arm64: dts: freescale: Add EL2 virtual timer interrupt
  arm64: dts: intel: Add EL2 virtual timer interrupt
  arm64: dts: mediatek: Add EL2 virtual timer interrupt
  arm64: dts: nvidia: Add EL2 virtual timer interrupt
  arm64: dts: qcom: Add EL2 virtual timer interrupt
  arm64: dts: realtek: Add EL2 virtual timer interrupt
  arm64: dts: rockchip: Add EL2 virtual timer interrupt
  arm64: dts: sprd: Add EL2 virtual timer interrupt
  arm64: dts: xilinx: Add EL2 virtual timer interrupt

 .../bindings/timer/arm,arch_timer.yaml        | 21 +++----
 .../arm64/boot/dts/allwinner/sun55i-a523.dtsi |  3 +-
 .../boot/dts/amlogic/amlogic-a4-common.dtsi   |  8 ---
 arch/arm64/boot/dts/amlogic/amlogic-a4.dtsi   |  8 +++
 arch/arm64/boot/dts/amlogic/amlogic-a5.dtsi   |  9 +++
 arch/arm64/boot/dts/amlogic/amlogic-s6.dtsi   |  3 +-
 arch/arm64/boot/dts/amlogic/amlogic-s7.dtsi   |  3 +-
 arch/arm64/boot/dts/amlogic/amlogic-s7d.dtsi  |  3 +-
 .../boot/dts/amlogic/meson-g12-common.dtsi    | 13 -----
 arch/arm64/boot/dts/amlogic/meson-g12.dtsi    |  9 +++
 arch/arm64/boot/dts/amlogic/meson-sm1.dtsi    | 10 ++++
 arch/arm64/boot/dts/bst/bstc1200.dtsi         |  3 +-
 arch/arm64/boot/dts/exynos/axis/artpec9.dtsi  |  3 +-
 arch/arm64/boot/dts/exynos/exynos2200.dtsi    |  3 +-
 arch/arm64/boot/dts/exynos/exynos990.dtsi     |  3 +-
 arch/arm64/boot/dts/exynos/exynosautov9.dtsi  |  3 +-
 arch/arm64/boot/dts/exynos/google/gs101.dtsi  |  3 +-
 .../boot/dts/freescale/imx91_93_common.dtsi   |  3 +-
 arch/arm64/boot/dts/freescale/imx94.dtsi      |  3 +-
 arch/arm64/boot/dts/freescale/imx95.dtsi      |  3 +-
 arch/arm64/boot/dts/freescale/imx952.dtsi     |  3 +-
 arch/arm64/boot/dts/freescale/s32n79.dtsi     |  3 +-
 .../arm64/boot/dts/intel/socfpga_agilex5.dtsi |  3 +-
 arch/arm64/boot/dts/mediatek/mt6779.dtsi      |  3 +-
 arch/arm64/boot/dts/mediatek/mt8186.dtsi      |  3 +-
 arch/arm64/boot/dts/mediatek/mt8188.dtsi      |  3 +-
 arch/arm64/boot/dts/mediatek/mt8192.dtsi      |  3 +-
 arch/arm64/boot/dts/mediatek/mt8195.dtsi      |  3 +-
 arch/arm64/boot/dts/nvidia/tegra194.dtsi      |  2 +
 arch/arm64/boot/dts/nvidia/tegra234.dtsi      |  3 +-
 arch/arm64/boot/dts/qcom/eliza.dtsi           |  3 +-
 arch/arm64/boot/dts/qcom/hamoa.dtsi           |  3 +-
 arch/arm64/boot/dts/qcom/kaanapali.dtsi       |  3 +-
 arch/arm64/boot/dts/qcom/kodiak.dtsi          |  3 +-
 arch/arm64/boot/dts/qcom/lemans.dtsi          |  3 +-
 arch/arm64/boot/dts/qcom/monaco.dtsi          |  3 +-
 arch/arm64/boot/dts/qcom/sar2130p.dtsi        |  3 +-
 arch/arm64/boot/dts/qcom/sc8280xp.dtsi        |  3 +-
 arch/arm64/boot/dts/qcom/sm4450.dtsi          |  3 +-
 arch/arm64/boot/dts/qcom/sm8250.dtsi          |  3 +-
 arch/arm64/boot/dts/qcom/sm8350.dtsi          |  3 +-
 arch/arm64/boot/dts/qcom/sm8450.dtsi          |  3 +-
 arch/arm64/boot/dts/qcom/sm8550.dtsi          |  3 +-
 arch/arm64/boot/dts/qcom/sm8650.dtsi          |  3 +-
 arch/arm64/boot/dts/qcom/sm8750.dtsi          |  3 +-
 arch/arm64/boot/dts/realtek/kent.dtsi         |  2 +-
 arch/arm64/boot/dts/realtek/rtd16xx.dtsi      |  3 +-
 arch/arm64/boot/dts/rockchip/rk356x-base.dtsi |  3 +-
 arch/arm64/boot/dts/sprd/sc9863a.dtsi         |  3 +-
 arch/arm64/boot/dts/sprd/ums512.dtsi          |  3 +-
 arch/arm64/boot/dts/sprd/ums9620.dtsi         |  3 +-
 arch/arm64/boot/dts/xilinx/versal-net.dtsi    |  3 +-
 drivers/acpi/arm64/gtdt.c                     | 42 +++++++++++++-
 drivers/clocksource/arm_arch_timer.c          | 55 +++++++++++--------
 54 files changed, 206 insertions(+), 102 deletions(-)

-- 
2.47.3