[v2,0/3] Add Microchip IPC mailbox

Message

Valentina Fernandez Oct. 25, 2024, 12:51 p.m. UTC

Hello all,

This series adds support for the Microchip Inter-Processor Communication
(IPC) mailbox driver.

I am submitting this v2 with the IPC mailbox patches and without the
IPC remoteproc drivers, as suggested in v1 [1].

Microchip's family of RISC-V SoCs typically has one or more clusters
that can be configured to run in Asymmetric Multi-Processing (AMP) mode.

The Microchip IPC is used to send messages between processors using
an interrupt signaling mechanism. The driver uses the RISC-V Supervisor
Binary Interface (SBI) to communicate with software running in machine
mode (M-mode) to access the IPC hardware block.

Additional details on the Microchip vendor extension and the IPC
function IDs described in the driver can be found in the following
documentation:

https://github.com/linux4microchip/microchip-sbi-ecall-extension

The PIC64GX MPU has a Mi-V IHC block, this will be added to the PIC64GX
dts after the initial upstreaming [2].

[1] https://patchwork.kernel.org/project/linux-remoteproc/cover/[e-mail]/
[2] https://patchwork.kernel.org/project/linux-riscv/patch/[e-mail]/


changes since v1:
  - use kmalloc and __pa() instead of DMA API
  - fix size of buf_base to avoid potential buffer overflow
  - add kernel doc for exported functions (mchp_ipc_get_chan_id)
  - use EXPORT_SYMBOL_GPL instead of EXPORT_SYMBOL
  - drop unnecessary blank line and fix alignment issues
  - drop of_match_ptr
  - move MODULE_DEVICE_TABLE next to the definition
  - reword subject from riscv: asm: vendorid_list to riscv: sbi: vendorid_list
  - remove the word "driver" from dt-binding commit subject
  - make interrupt-names a required property for all cases
  - add dependency on COMPILE_TEST and ARCH_MICROCHIP

Regards,
Valentina

Valentina Fernandez (3):
  riscv: sbi: vendorid_list: Add Microchip Technology to the vendor list
  dt-bindings: mailbox: add binding for Microchip IPC mailbox controller
  mailbox: add Microchip IPC support

 .../bindings/mailbox/microchip,sbi-ipc.yaml   | 108 ++++
 arch/riscv/include/asm/vendorid_list.h        |   1 +
 drivers/mailbox/Kconfig                       |  13 +
 drivers/mailbox/Makefile                      |   2 +
 drivers/mailbox/mailbox-mchp-ipc-sbi.c        | 537 ++++++++++++++++++
 include/linux/mailbox/mchp-ipc.h              |  23 +
 6 files changed, 684 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/mailbox/microchip,sbi-ipc.yaml
 create mode 100644 drivers/mailbox/mailbox-mchp-ipc-sbi.c
 create mode 100644 include/linux/mailbox/mchp-ipc.h