[PATCH 0/2] mailbox: add Axiado AX3005 mailbox driver

[Swark Yang]

The Axiado AX3005 SoC integrates a mailbox controller that provides
inter-processor communication channels between the host CPU and the
on-chip co-processor.

The controller exposes 16 fixed-function channels split into two
groups: 8 TX channels and 8 RX channels. Each channel has a
hardware FIFO and a control/status register, while TX and RX
channels reside in separate MMIO register regions.

Only the RX channels expose interrupts to the host CPU.
TX completion is detected by polling the FIFO empty status, so
txdone_poll is used instead of txdone_irq. RX delivery uses a
threaded IRQ per channel because draining a mailbox message word by
word is not appropriate in hard IRQ context.

The ax3005.dtsi mailbox node will follow in a separate patch once
the AX3005 devicetree series currently under review has been merged.

This series consists of:
1. dt-bindings: mailbox: add Axiado AX3005 mailbox
2. mailbox: add Axiado AX3005 mailbox driver

The corresponding MAINTAINERS entry is added incrementally by the
two patches: the binding path in patch 1 and the driver path in
patch 2.

Testing:
Tested on AX3005 using an out-of-tree MCTP-over-mailbox transport
driver, not yet submitted upstream, as the mailbox client. The test
exercised channel 0 for TX and channel 8 for RX.

Verified end to end by issuing a PLDM Firmware Update command from
OpenBMC over MCTP and routing it through this mailbox driver to the
on-chip coprocessor. The firmware update completed successfully,
and the resulting image passed verification.

Signed-off-by: Swark Yang <syang@xxxxxxxxxx>
---
Swark Yang (2):
      dt-bindings: mailbox: add Axiado AX3005 mailbox
      mailbox: add Axiado AX3005 mailbox driver

 .../bindings/mailbox/axiado,ax3005-mailbox.yaml    |  98 ++++++
 MAINTAINERS                                        |   8 +
 drivers/mailbox/Kconfig                            |  10 +
 drivers/mailbox/Makefile                           |   2 +
 drivers/mailbox/axiado-mailbox.c                   | 379 +++++++++++++++++++++
 5 files changed, 497 insertions(+)
---
base-commit: 1590cf0329716306e948a8fc29f1d3ee87d3989f
change-id: 20260728-upstream-axiado-ax3005-mailbox-upstream-86feaa7edf49

Best regards,
-- 
Swark Yang <syang@xxxxxxxxxx>