[PATCH v4 0/3] Add Firmware Upload support for beagleplay cc1352

[Ayush Singh]

Adds support for beagleplay cc1352 co-processor firmware upgrade using
kernel Firmware Upload API. Uses ROM based bootloader present in
cc13x2x7 and cc26x2x7 platforms for flashing over UART.

Communication with the bootloader can be moved out of gb-beagleplay
driver if required, but I am keeping it here since there are no
immediate plans to use the on-board cc1352p7 for anything other than
greybus (BeagleConnect Technology). Additionally, there do not seem to
any other devices using cc1352p7 or its cousins as a co-processor.

Bootloader backdoor and reset GPIOs are used to enable cc1352p7 bootloader
backdoor for flashing. Flashing is skipped in case we are trying to flash
the same image as the one that is currently present. This is determined by
CRC32 calculation of the supplied firmware and flash data.

We also do a CRC32 check after flashing to ensure that the firmware was
flashed properly.

Link: https://www.ti.com/lit/ug/swcu192/swcu192.pdf Ti CC1352P7 Technical Specification

Changes in v4:
- Add acks properly
- Fix Kconfig warning by adding select FW_LOADER
- Link to v3: https://lore.kernel.org/r/20240825-beagleplay_fw_upgrade-v3-0-8f424a9de9f6@beagleboard.org

Changes in v3:
- Spelling fixes in cover letter
- Add Ack by Rob Herring on Patch 1
- Link to v2: https://lore.kernel.org/r/20240801-beagleplay_fw_upgrade-v2-0-e36928b792db@beagleboard.org

Changes in v2:
- Spelling fixes
- Rename boot-gpios to bootloader-backdoor-gpios
- Add doc comments
- Add check to ensure firmware size is 704 KB
- Link to v1: https://lore.kernel.org/all/20240719-beagleplay_fw_upgrade-v1-0-8664d4513252@beagleboard.org

Signed-off-by: Ayush Singh <ayush at beagleboard.org>
---
Ayush Singh (3):
      dt-bindings: net: ti,cc1352p7: Add bootloader-backdoor-gpios
      arm64: dts: ti: k3-am625-beagleplay: Add bootloader-backdoor-gpios to cc1352p7
      greybus: gb-beagleplay: Add firmware upload API

 .../devicetree/bindings/net/ti,cc1352p7.yaml       |   7 +
 arch/arm64/boot/dts/ti/k3-am625-beagleplay.dts     |   3 +-
 drivers/greybus/Kconfig                            |   2 +
 drivers/greybus/gb-beagleplay.c                    | 658 ++++++++++++++++++++-
 4 files changed, 656 insertions(+), 14 deletions(-)
---
base-commit: f76698bd9a8ca01d3581236082d786e9a6b72bb7
change-id: 20240715-beagleplay_fw_upgrade-43e6cceb0d3d

Best regards,
-- 
Ayush Singh <ayush at beagleboard.org>