[PATCH v2 0/5] arm64: dts: freescale: Share the Toradex Cortex-M UART overlay

[Ernest Van Hoecke]

Several Toradex modules assign one UART to firmware running on their
Cortex-M core: Verdin UART_4 on Verdin iMX8M Mini, Verdin iMX8M Plus
and Verdin iMX95, Aquila UART_4 on Aquila iMX95 and SER0 on Toradex
SMARC iMX95. The overlays reserving it only differ in the UART
instance.

Label that UART uart_mcu in each module device tree and share one
overlay, imx-tdx-uart-mcu.dtso, which reserves the labelled UART. The
merged Verdin iMX8M Mini overlay becomes the shared one, and the
combined Verdin iMX8M Mini DTB keeps its name. NXP's imx9-mqs.dtso
uses the same pattern with its mqs1_conflict_dev board label.

The overlays mark the port as reserved so Linux does not claim it.
Firmware remains responsible for configuring the UART and its pads.

Signed-off-by: Ernest Van Hoecke <ernest.vanhoecke@xxxxxxxxxxx>
---
Changes in v2:
- Share one overlay through a uart_mcu label instead of adding
  identical per-module overlays (Frank), and include the merged Verdin
  iMX8M Mini overlay
- Add Verdin iMX8M Plus, previously posted with the Verdin iMX8M OV5640
  series:
  https://lore.kernel.org/r/20261001-verdin-imx8mp-hmp-camera-ready-v2-2-7d1343ecd3ec@xxxxxxxxxxx
- Drop the Verdin iMX95 NAU8822 BTL patch, now covered by the shared
  NAU8822 BTL series:
  https://lore.kernel.org/all/20261022-imx-nau8822-btl-v2-0-b4221ed43650@xxxxxxxxxxx/
- Rebase onto imx/dt64
- Link to v1: https://lore.kernel.org/r/20260922-v1-imx95-overlays-v1-0-694100afb4bc@xxxxxxxxxxx

---
Ernest Van Hoecke (5):
      arm64: dts: freescale: imx8mm-verdin: Share the UART_4 MCU overlay
      arm64: dts: freescale: imx8mp-verdin: Add Cortex-M7 UART_4 overlay
      arm64: dts: freescale: imx95-verdin: Add Cortex-M7 UART_4 overlay
      arm64: dts: freescale: imx95-aquila: Add Cortex-M7 UART_4 overlay
      arm64: dts: freescale: imx95-toradex-smarc: Add Cortex-M7 SER0 overlay

 arch/arm64/boot/dts/freescale/Makefile                    | 15 +++++++++++++--
 arch/arm64/boot/dts/freescale/imx-tdx-uart-mcu.dtso       | 14 ++++++++++++++
 .../arm64/boot/dts/freescale/imx8mm-verdin-uart4-mcu.dtso | 14 --------------
 arch/arm64/boot/dts/freescale/imx8mm-verdin.dtsi          |  2 +-
 arch/arm64/boot/dts/freescale/imx8mp-verdin.dtsi          |  2 +-
 arch/arm64/boot/dts/freescale/imx95-aquila.dtsi           |  2 +-
 arch/arm64/boot/dts/freescale/imx95-toradex-smarc.dtsi    |  2 +-
 arch/arm64/boot/dts/freescale/imx95-verdin.dtsi           |  2 +-
 8 files changed, 32 insertions(+), 21 deletions(-)
---
base-commit: 7f47e8eafbf55a2ad0697e5d28f5e6cff2fa42f9
change-id: 20260922-v1-imx95-overlays-89b3a9185b93

Best regards,
-- 
Ernest Van Hoecke <ernest.vanhoecke@xxxxxxxxxxx>