On 12/07/18 04:46, A.s. Dong wrote:

Hi Sudeep,

quoted

-----Original Message-----
From: Sudeep Holla [mailto:sudeep.holla at arm.com]
Sent: Thursday, July 12, 2018 12:49 AM
To: A.s. Dong <aisheng.dong@nxp.com>; linux-arm-
kernel at lists.infradead.org
Cc: Sudeep Holla <redacted>; dongas86 at gmail.com; dl-linux-
imx [off-list ref]; kernel at pengutronix.de; Fabio Estevam
[off-list ref]; shawnguo at kernel.org; Cl?ment Faure
[off-list ref]
Subject: Re: [PATCH V4 0/5] soc: imx: add scu firmware api support

On 08/07/18 15:56, Dong Aisheng wrote:

quoted

Unlike the former i.MX Architectures, the new generation i.MX8 SoCs
(e.g. MX8QXP and MX8QM) contain a system controller which runs on a
dedicated Cortex-M core to provide power, clock, Pad, and resource
management. Communication between the host processor running an OS

and

quoted

the system controller happens through a SCU protocol.
This patchset adds the SCU APIs which is implemented based on MU and
will be used by different system components.

It mainly consists of below parts:
1) MU mailbox driver
1) Implementation of the IPC functions based on MUs (client side).

I do understand the firmware might be already released for the current
generation of platforms, but instead of adding to the fragmentation, it would
be good to migrated to ARM SCMI for future platforms.

This system controller communication protocol is already so fragmented (we
have TI SCI, QCOM RPM, Nvidia Tegra BPMP, ARM SCPI and so on..
and now this i.MX specific one added to that), the main intention of ARM
SCMI is to stop that. The idea is for any Power Control System
Architecture(PCSA) compliant systems or any similar systems, SCMI should
be the standard communication protocol.

That sounds good and worth a look.
Copy SCU firmware guys if more comments.
BTW, i.MX SCU provides more services than just power related. 
Not sure if ARM SCMI can cover it.

Sure, we can extend the specification to cover those as generic
protocols. If they are too NXP specific, then SCMI has options to
use vendor specific protocols. I am interested to know the requirements.
-- 
Regards,
Sudeep