Re: [RFC 0/2] Add support for SCMI QTI Memlat Vendor Protocol

From: Cristian Marussi
Date: Thu Nov 03 2022 - 05:41:44 EST


On Thu, Nov 03, 2022 at 10:28:30AM +0530, Sibi Sankar wrote:
> The patch series documents the bindings and adds support for the
> SCMI QTI memlat (memory latency) vendor protocol. The protocol takes
> in several tuneables including the IPM ratio (Instructions Per Miss),
> bus bandwidth requirements and PMU maps to enable frequency scaling
> of various buses (L3/LLCC/DDR). The scaling is performed by the HW
> memory latency governor running on the CPUSS Control Processor.
>
> Depends on CPUCP mailbox driver:
> https://patchwork.kernel.org/project/linux-arm-msm/cover/1663135386-26270-1-git-send-email-quic_sibis@xxxxxxxxxxx/
>

[+ CC: souvik.chakravarty@xxxxxxx ]

Hi Sibi,

Nice to see vendor protocols starting to make their way into upstream !

I only glanced through the series as of now, and I'd have a few
questions before going on with the review:

- why this protocol is dependent on a specific transport ?
Is it to compile it only on platform supoprting it without adding
a per-protocol Kconfig ?

Protocols are anyway enumerated at SCMI stack probe time so even if it
is not there it just won't be activated...I maybe missing something.

Thanks,
Cristian