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Subject: Re: [PATCH V4 2/2] firmware: arm_scmi: add smc/hvc transport
To:     Sudeep Holla <sudeep.holla@arm.com>, Peng Fan <peng.fan@nxp.com>
Cc:     "robh+dt@kernel.org" <robh+dt@kernel.org>,
        "viresh.kumar@linaro.org" <viresh.kumar@linaro.org>,
        dl-linux-imx <linux-imx@nxp.com>,
        "linux-arm-kernel@lists.infradead.org" 
        <linux-arm-kernel@lists.infradead.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "devicetree@vger.kernel.org" <devicetree@vger.kernel.org>
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From:   Florian Fainelli <f.fainelli@gmail.com>
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Message-ID: <d9734fd6-f855-296b-3a0b-ffc45ed0e3cb@gmail.com>
Date:   Thu, 5 Mar 2020 09:27:00 -0800
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On 3/5/20 8:06 AM, Sudeep Holla wrote:
> On Thu, Mar 05, 2020 at 11:25:35AM +0000, Peng Fan wrote:
> 
> [...]
> 
>>>
>>> Yes, this may fix the issue. However I would like to know if we need to support
>>> multiple channels/shared memory simultaneously. It is fair requirement and
>>> may need some work which should be fine.
>>
>> Do you have any suggestions? Currently I have not worked out an good
>> solution.
>>
> 
> TBH, I haven't given it a much thought. I would like to know if people
> are happy with just one SMC channel for SCMI or do they need more ?
> If they need it, we can try to solve it. Otherwise, what you have will
> suffice IMO.

On our platforms we have one channel/shared memory area/mailbox instance
for all standard SCMI protocols, and we have a separate channel/shared
memory area/mailbox driver instance for a proprietary one. They happen
to have difference throughput requirements, hence the split.

If I read Peng's submission correctly, it seems to me that the usage
model described before is still fine.
-- 
Florian