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Date:   Tue, 19 Sep 2023 19:51:10 +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>
References: <20230914115753.9064-1-lihuisong@huawei.com>
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From:   "lihuisong (C)" <lihuisong@huawei.com>
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在 2023/9/18 16:43, Sudeep Holla 写道:
> On Fri, Sep 15, 2023 at 03:04:57PM +0800, lihuisong (C) wrote:
>> 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.
>>
> OK, but please post the changes in the *driver* you ought to use this channel
> type. Your change just allows the drivers to use it but it doesn't contain
> any driver making use of it. So please post that change as well to understand
> the issue better. It helps in the review.
All right, I will post it ASAP.
>