[PATCH v4 0/2] riscv: sophgo: add mailbox support for CV18XX series SoC

[Junhui Liu]

Sophgo CV18XX series SoC has a mailbox module used to pass messages to
asymmetric processors. It has a total of 8 channels, each channel has a
length of 64bit.

Since the dts of cv18xx series are undergoing rework [1], the mailbox
node is not added in dts. It will be added later with the user (the
remoteproc node) together.

Tested on Milk-V Duo with CV1800B SoC, Milk-V Duo256M with SG2002 SoC
and Milk-V Duo S with SG2000 SoC by the mailbox-test client [2].

link: https://lore.kernel.org/sophgo/174710989159.597941.17259091695735282020.b4-ty@gmail.com/T/#m159cc72c6e4f89bfe14932f38ae93991e8cfa712 [1]
link: https://gist.github.com/pigmoral/70d0d0164dff7f9b95f59df50ef309d8 [2]

---
Changes in v4:
- Move processor ID description to the mbox-cells property in
  dt-bindings.
- Drop the patch of adding mailbox node in dts for now.
- Add missing `__iomem` in the `MBOX_CONTEXT_BASE_INDEX` macro.
- Pass the address of the value read from the mailbox to
  `mbox_chan_received_data()` instead of the mailbox's address.
- Link to v3: https://lore.kernel.org/r/20250428-cv18xx-mbox-v3-0-ed18dfd836d1@pigmoral.tech

Changes in v3:
- Update cv18x to CV18XX in commit messages and descriptions.
- Remove the `interrupt-names` property in dt-bindings, dts and driver.
- Move the mailbox node in dts to satisfy the address order.
- Remove `OF` dependency in Kconfig and the driver.
- Add copyright in the driver.
- Reorder the processes in dt-bindings and change the `RECV_CPU` macro
  definition from 2 to 1 in the driver.
- Clean up and improve macro definitions and register access methods in
  the driver.
- Improve the return value handling in the interrupt handler functions.
- Implement the `cv1800_last_tx_done` function.
- Link to v2: https://lore.kernel.org/r/SYBP282MB223825D5903777B937A8A377C4A02@SYBP282MB2238.AUSP282.PROD.OUTLOOK.COM

Changes in v2:
- drop 'recvid' 'sender' in dt-bindings
- fix compatible to 'cv1800-mailbox', and change filenames too
- change #mbox-cell to 2, for <channel tagert_cpu>
- add struct cv1800_mbox_chan_priv and function cv1800_mbox_xlate to extract
  informations in mbox devicetree node of mailbox client
- Link to v1: https://lore.kernel.org/r/SYBP282MB2238DE0DA19C6EF411B2356CC4CE2@SYBP282MB2238.AUSP282.PROD.OUTLOOK.COM

---
Yuntao Dai (2):
      dt-bindings: mailbox: add Sophgo CV18XX series SoC
      mailbox: sophgo: add mailbox driver for CV18XX series SoC

 .../bindings/mailbox/sophgo,cv1800b-mailbox.yaml   |  60 ++++++
 drivers/mailbox/Kconfig                            |  10 +
 drivers/mailbox/Makefile                           |   2 +
 drivers/mailbox/cv1800-mailbox.c                   | 220 +++++++++++++++++++++
 4 files changed, 292 insertions(+)
---
base-commit: a5806cd506af5a7c19bcd596e4708b5c464bfd21
change-id: 20250421-cv18xx-mbox-6282d1e1734c

Best regards,
-- 
Junhui Liu <junhui.liu at pigmoral.tech>