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From:   Peng Fan <peng.fan@nxp.com>
To:     Sudeep Holla <sudeep.holla@arm.com>
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Subject: RE: [PATCH V3 2/2] firmware: arm_scmi: add smc/hvc transport
Thread-Topic: [PATCH V3 2/2] firmware: arm_scmi: add smc/hvc transport
Thread-Index: AQHV7HUEw4K6S9kW+0Sj3fQlJbhvlqgwzHcAgACkEkA=
Date:   Sat, 29 Feb 2020 02:07:30 +0000
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Hi Sudeep,

> Subject: Re: [PATCH V3 2/2] firmware: arm_scmi: add smc/hvc transport
>=20
> On Wed, Feb 26, 2020 at 03:12:51PM +0800, peng.fan@nxp.com wrote:
> > From: Peng Fan <peng.fan@nxp.com>
> >
> > Take arm,smc-id as the 1st arg, and protocol id as the 2nd arg when
> > issuing SMC/HVC. Since we need protocol id, so add this parameter
>=20
> And why do we need protocol id here ? I couldn't find it out myself.
> I would like to know why/what/how is it used in the firmware(smc/hvc
> handler). I hope you are not mixing the need for multiple channel with
> protocol id ? One can find out id from the command itself, no need to pas=
s it
> and hence asking here for more details.

When each protocol needs its own shmem area, we need let firmware
know which shmem area to parse the message from. Without protocol
id, firmware not know which shmem area should use. Hope this is clear.

Thanks,
Peng.

>=20
> --
> Regards,
> Sudeep