Re: [PATCH v2 0/3] MCTP over PCC

On 5/29/2024 3:18 AM, admiyo@os.amperecomputing.com wrote:

From: Adam Young <redacted>

This series adds support for the Management Control Transport Protocol (MCTP)
over the Platform Communication Channel (PCC) mechanism.

MCTP defines a communication model intended to
facilitate communication between Management controllers
and other management controllers, and between Management
controllers and management devices

PCC is a mechanism for communication between components within
the  Platform.  It is a composed of shared memory regions,
interrupt registers, and status registers.

The MCTP over PCC driver makes use of two PCC channels. For
sending messages, it uses a Type 3 channel, and for receiving
messages it uses the paired Type 4 channel.  The device
and corresponding channels are specified via ACPI.

Changes in V2

- All Variable Declarations are in reverse Xmass Tree Format
- All Checkpatch Warnings Are Fixed
- Removed Dead code
- Added packet tx/rx stats
- Removed network physical address.  This is still in
   disucssion in the spec, and will be added once there
   is consensus. The protocol can be used with out it.
   This also lead to the removal of the Big Endian
   conversions.
- Avoided using non volatile pointers in copy to and from io space
- Reorderd the patches to put the ACK check for the PCC Mailbox
   as a pre-requisite.  The corresponding change for the MCTP
   driver has been inlined in the main patch.
- Replaced magic numbers with constants, fixed typos, and other
   minor changes from code review.

Code Review Change not made

- Did not change the module init unload function to use the
   ACPI equivalent as they do not remove all devices prior
   to unload, leading to dangling references and seg faults.

Adam Young (3):
   mctp pcc: Check before sending MCTP PCC response ACK
   mctp pcc: Allow PCC Data Type in MCTP resource.
   mctp pcc: Implement MCTP over PCC Transport

  drivers/acpi/acpica/rsaddr.c |   2 +-
  drivers/mailbox/pcc.c        |   5 +-
  drivers/net/mctp/Kconfig     |  13 ++
  drivers/net/mctp/Makefile    |   1 +
  drivers/net/mctp/mctp-pcc.c  | 361 +++++++++++++++++++++++++++++++++++
  include/acpi/pcc.h           |   1 +
  6 files changed, 381 insertions(+), 2 deletions(-)
  create mode 100644 drivers/net/mctp/mctp-pcc.c

Tested OK on Arm FVP.

Tested-by: John Chung <redacted>