[PATCH v2 0/4] arm64: dts: qcom: Add support for Radxa Dragon Q8B

From: Xilin Wu

Date: Fri Oct 09 2026 - 03:57:27 EST


Hi,

The Radxa Dragon Q8B is a single-board computer based on the Qualcomm
Snapdragon 8cx Gen 3 (SC8280XP) platform.

The board provides UFS and microSD storage, two M.2 M-key slots, an M.2
E-key slot, a QPS615/TC9563 PCIe switch, USB Type-C ports with DisplayPort
alternate mode, USB Type-A ports, HDMI 2.1 output, headset audio and
a 40-pin expansion header.

This series adds the initial device tree support for the board. It
describes the regulators, storage, PCIe topology, USB and display outputs,
audio, remote processors, thermal sensors, RTC, EEPROM and expansion
header. Build targets for both the regular and EL2 device trees are
included.

The TC9563 power-control driver powers off external downstream ports whose
device tree nodes have status = "disabled". On the Dragon Q8B,
config-space reads to these powered-off port functions raise an Arm SError
instead of returning an all-ones PCI error response, preventing the board
from completing boot.

The PCI OF change to skip config-space reads for unavailable DT-described
bridge functions has been split out into a separate two-patch series for
the PCI tree. Disabled endpoint functions remain discoverable so PCI
fixups can still be applied, while driver binding continues to be
suppressed later.

The onboard HDMI output is provided by a Chrontel CH7218A DisplayPort 1.4
to HDMI 2.1 protocol converter. The device boots its firmware from on-chip
flash and requires no host-side configuration, so the series documents it
and adds it to the simple bridge driver.

The series also documents the board compatible. The SC8280XP TLMM binding
change allowing gpio-line-names has already been applied and is no longer
included in this series.

The PCI change is required before applying the board DTS patch; otherwise
the disabled TC9563 downstream ports cause a boot-time SError. The display
binding and driver patches can otherwise be applied independently through
the DRM tree.

Signed-off-by: Xilin Wu <sophon@xxxxxxxxx>
---
Changes in v2:
- Describe the TC9563 embedded GPIO controller and use its GPIOs 2 and 3
for the external downstream port PERST# reset lines.
- Drop "PCI: of: Avoid config reads for disabled bridge nodes"; split it
into a separate two-patch PCI series, including the kernel-doc fix.
- Drop "dt-bindings: pinctrl: qcom,sc8280xp-tlmm: allow gpio-line-names"
because it has already been applied.
- Link to v1: https://patch.msgid.link/20260901-q8b-dts-v1-0-7de0b6a73d08@xxxxxxxxx

To: Andrzej Hajda <andrzej.hajda@xxxxxxxxx>
To: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
To: Robert Foss <rfoss@xxxxxxxxxx>
To: Laurent Pinchart <Laurent.pinchart@xxxxxxxxxxxxxxxx>
To: Jonas Karlman <jonas@xxxxxxxxx>
To: Jernej Skrabec <jernej.skrabec@xxxxxxxxx>
To: Luca Ceresoli <luca.ceresoli@xxxxxxxxxxx>
To: David Airlie <airlied@xxxxxxxxx>
To: Simona Vetter <simona@xxxxxxxx>
To: Maarten Lankhorst <maarten.lankhorst@xxxxxxxxxxxxxxx>
To: Maxime Ripard <mripard@xxxxxxxxxx>
To: Thomas Zimmermann <tzimmermann@xxxxxxx>
To: Rob Herring <robh@xxxxxxxxxx>
To: Krzysztof Kozlowski <krzk+dt@xxxxxxxxxx>
To: Conor Dooley <conor+dt@xxxxxxxxxx>
To: Bjorn Andersson <andersson@xxxxxxxxxx>
To: Konrad Dybcio <konradybcio@xxxxxxxxxx>
Cc: dri-devel@xxxxxxxxxxxxxxxxxxxxx
Cc: devicetree@xxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: linux-arm-msm@xxxxxxxxxxxxxxx

---
Xilin Wu (4):
dt-bindings: display: bridge: simple: document Chrontel CH7218A
drm/bridge: simple: add Chrontel CH7218A
dt-bindings: arm: qcom: document Radxa Dragon Q8B
arm64: dts: qcom: sc8280xp: add Radxa Dragon Q8B

Documentation/devicetree/bindings/arm/qcom.yaml | 1 +
.../bindings/display/bridge/simple-bridge.yaml | 1 +
arch/arm64/boot/dts/qcom/Makefile | 2 +
.../boot/dts/qcom/sc8280xp-radxa-dragon-q8b.dts | 2102 ++++++++++++++++++++
drivers/gpu/drm/bridge/simple-bridge.c | 5 +
5 files changed, 2111 insertions(+)
---
base-commit: e30626823a406725ce29bc75cb8ec467d3e1e326
change-id: 20260901-q8b-dts-a3afc5f9b8b2
prerequisite-change-id: 20260507-sc8280xp-qup-pinctrl-5ab8af9be35f:v2
prerequisite-patch-id: 1060ddda6f3ff07b36691a0dd7d783a5be2cc993

Best regards,
--
Xilin Wu <sophon@xxxxxxxxx>