[PATCH v3 7/9] firmware: arm_scmi: Add ACPI PCC transport

[Sudeep Holla]

On Mon, Aug 24, 2026 at 01:17:09PM -0700, Jonathan Cameron wrote:
> On Thu, 13 Aug 2026 12:33:02 +0100
> Sudeep Holla <sudeep.holla at kernel.org> wrote:
> 
> > Introduce a new SCMI transport that uses ACPI PCCT (PCC) subspaces via
> > the Linux PCC mailbox layer. Parse ACPI _DSD data to map protocol
> > associations to PCC transport UIDs. Support common and
> > protocol-exclusive A2P channels, plus optional common or
> > protocol-exclusive P2A channels for notifications.
> > 
> > Key points:
> > - new CONFIG_ARM_SCMI_TRANSPORT_PCC option
> > - integration with SCMI core via scmi_desc and transport ops
> > - response and notification fetch from PCC shared memory
> > - ACPI device matching and registration via the ACPI transport macro
> > 
> > This enables SCMI to be exercised over PCC on ACPI platforms.
> > 
> > Signed-off-by: Sudeep Holla <sudeep.holla at kernel.org>
> Hi Sudeep
> 
> This is quite dense and ACPI parsing code is always 'interesting'
> Anyhow some comments inline
> 

Indeed quite dense to even parse the comments. It could be my brain which
is still recovering from the flu, but I can't respond to them inline. I
think I have taken most of the suggestions(saying most as I might have
missed unintentionally). I might have gone overboard with some macros to
eliminate random magic offsets. I will post v4 soon.

Thanks again for all the review comments. I am still debating if I need
to break this into 2 patches(technically yes, motivationally not yet 😄)

-- 
Regards,
Sudeep