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Date:   Fri, 15 Sep 2023 15:04:57 +0800
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Subject: Re: [PATCH] mailbox: pcc: export the PCC subspace type
To:     Sudeep Holla <sudeep.holla@arm.com>
CC:     <rafael@kernel.org>, <rafael.j.wysocki@intel.com>,
        <linux-acpi@vger.kernel.org>, <linux-kernel@vger.kernel.org>,
        <liuyonglong@huawei.com>
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 <20230914161335.rz6fn4w2pqzz4wdp@bogus>
From:   "lihuisong (C)" <lihuisong@huawei.com>
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在 2023/9/15 0:13, Sudeep Holla 写道:
> On Thu, Sep 14, 2023 at 07:57:53PM +0800, Huisong Li wrote:
>> As stated in APCI spec, the size of the subspace shared memory region may
>> be different for different types. So it is useful for driver to fill PCC
>> communication space. But the driver used this PCC channel doesn't know what
>> is the subspace type of the channel.
>>
>> So export the PCC subspace type by requesting PCC channel.
>>
> I would prefer to avoid this, but please post it with user to get better
> understanding of it.
Hi Sudeep,

Thanks for your fast review.
Sorry, I cannot fully understand what you mean. What should I do for it?
Currently, it seems that the subspace type in all drivers used PCC is 
fixed and not obtained from their platform.
IMO, PCCT is a best natural way to export it.

/Huisong