[PATCH v4 0/4] arm64: boot: dts: ti: k3-am62l: allow WKUP UART wakeup from LPM

[Kendall Willis]

K3 TI AM62L SoC supports wakeup from WKUP UART when the SoC is in the
DeepSleep low power mode. To allow wakeup from WKUP UART the target-module
device tree node is enabled. The ti-sysc interconnect target module driver
is used to configure the SYSCONFIG related registers. In this case, the
target module node configures the WKUP UART to be able to wakeup from
system suspend. The SYSC register is used to enable wakeup from system
suspend for the WKUP UART. Refer to 14.7.2.5 UART in the AM62L Technical
Reference Manual for registers referenced [1].

Other TI K3 SoCs configure the WKUP UART to wakeup from system suspend
using the ti-sysc target module driver. Refer to commit ce27f7f9e328
("arm64: dts: ti: k3-am62-wakeup: Configure ti-sysc for wkup_uart0") for
an example of this.

wkup_uart0 is not enabled to preserve the Linux console printing on uart0.

Testing
-------
Tested on AM62L EVM.

[1] https://www.ti.com/lit/ug/sprujb4a/sprujb4a.pdf

Signed-off-by: Kendall Willis <k-willis@xxxxxx>
---
Changes in v4:
- Fix target-module label to accurately describe the function being a
  target for wkup_uart0.
- Update commit messages with the fixed target-module label.
- Link to v3: https://lore.kernel.org/r/20260127-v6-19-wkup-uart-wakeup-v3-0-e7ccac761f3a@xxxxxx

Changes in v3:
- Add pin definition to wkup_uart0 node.
- Link to v2: https://lore.kernel.org/r/20260106-wkup-uart-wakeup-v2-0-fb4cbd56c827@xxxxxx

Changes in v2:
- Change subject of commit "arm64: boot: dts: ti: k3-am62l3-evm: enable
  target-module node" to better match the code logic of the patch.
- Link to v1: https://lore.kernel.org/r/20251230-wkup-uart-wakeup-v1-0-cd6e15f8d956@xxxxxx

---
Kendall Willis (4):
      arm64: dts: ti: k3-am62l: include WKUP_UART0 in wakeup peripheral window
      arm64: boot: dts: ti: k3-am62l-wakeup: create label for wkup_uart0 target-module
      arm64: boot: dts: ti: k3-am62l3-evm: define wkup_uart0 pins
      arm64: boot: dts: ti: k3-am62l3-evm: enable wkup_uart0_target node

 arch/arm64/boot/dts/ti/k3-am62l-wakeup.dtsi |  2 +-
 arch/arm64/boot/dts/ti/k3-am62l.dtsi        |  4 ++--
 arch/arm64/boot/dts/ti/k3-am62l3-evm.dts    | 15 +++++++++++++++
 3 files changed, 18 insertions(+), 3 deletions(-)
---
base-commit: 44982d352c33767cd8d19f8044e7e1161a587ff7
change-id: 20260127-v6-19-wkup-uart-wakeup-11c1c3d5b99a

Best regards,
-- 
Kendall Willis <k-willis@xxxxxx>