Re: [PATCH RFC 00/15] Convert Qualcomm RPM message RAM to a simple-mfd

From: Dmitry Baryshkov
Date: Sat Mar 11 2023 - 06:29:42 EST


On Sat, 11 Mar 2023 at 03:21, Konrad Dybcio <konrad.dybcio@xxxxxxxxxx> wrote:
>
> The Qualcomm RPM message RAM is a part of the RPM low-power processor's
> actual RAM that's exposed to the Application Processors as a MMIO-mapped
> region. It contains a couple of things, most notably the RPM master stats,
> detailing per-master (read: per-subsystem) sleep/wake statistics and an
> interrupt controller that's crucial to achieving full SoC clock and/or
> power collapse states (the MPM). This series tries to prepare the MSG
> RAM node to be a host for such devices.
>
> Depends on https://lore.kernel.org/linux-arm-msm/20230308011705.291337-1-konrad.dybcio@xxxxxxxxxx/
>
> to solve a warning in the example.
>
> The DTS commits don't add -cells or -ranges, as without children they're
> not of very much use. They'll be introduced along with subnodes.
>
> Signed-off-by: Konrad Dybcio <konrad.dybcio@xxxxxxxxxx>
> ---
> Konrad Dybcio (15):
> dt-bindings: mfd: Split out Qcom RPM MSG RAM
> arm64: dts: qcom: msm8916: Add simple-mfd to rpm_msg_ram
> arm64: dts: qcom: msm8953: Add simple-mfd to rpm_msg_ram
> arm64: dts: qcom: msm8976: Add simple-mfd to rpm_msg_ram
> arm64: dts: qcom: msm8994: Add simple-mfd to rpm_msg_ram
> arm64: dts: qcom: msm8996: Add simple-mfd to rpm_msg_ram
> arm64: dts: qcom: msm8998: Add simple-mfd to rpm_msg_ram
> arm64: dts: qcom: qcs404: Add simple-mfd to rpm_msg_ram
> arm64: dts: qcom: sdm630: Add simple-mfd to rpm_msg_ram
> arm64: dts: qcom: sm6115: Add simple-mfd to rpm_msg_ram
> arm64: dts: qcom: sm6125: Add simple-mfd to rpm_msg_ram
> arm64: dts: qcom: sm6375: Add simple-mfd to rpm_msg_ram
> ARM: dts: qcom-apq8084: Add simple-mfd to rpm_msg_ram
> ARM: dts: qcom-msm8226: Add simple-mfd to rpm_msg_ram
> ARM: dts: qcom-msm8974: Add simple-mfd to rpm_msg_ram

These commits do not demonstrate the need for simple-mfd (other than
qcom,mpm being mentioned in bindings). I'd suggest limiting the RFC to
a single platform populated with rpm_msg_ram child devices. This way
we can better understand the needs and the requirements for these
patches.


--
With best wishes
Dmitry