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Date:   Tue, 22 Feb 2022 13:46:29 +0300
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Subject: Re: [PATCH v3 8/9] drm/tegra: vic: Implement get_streamid_offset
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To:     Mikko Perttunen <cyndis@kapsi.fi>,
        Mikko Perttunen <mperttunen@nvidia.com>,
        thierry.reding@gmail.com, jonathanh@nvidia.com, joro@8bytes.org,
        will@kernel.org, robh+dt@kernel.org, robin.murphy@arm.com
Cc:     linux-tegra@vger.kernel.org, dri-devel@lists.freedesktop.org,
        iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org,
        devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org
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From:   Dmitry Osipenko <digetx@gmail.com>
In-Reply-To: <30033f5b-3fd1-22c7-896b-af034a4041df@kapsi.fi>
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22.02.2022 11:27, Mikko Perttunen пишет:
> On 2/21/22 22:10, Dmitry Osipenko wrote:
>> 21.02.2022 14:44, Mikko Perttunen пишет:
>>> On 2/19/22 20:54, Dmitry Osipenko wrote:
>>>> 19.02.2022 21:49, Dmitry Osipenko пишет:
>>>>> 18.02.2022 14:39, Mikko Perttunen пишет:
>>>>>> +static int vic_get_streamid_offset(struct tegra_drm_client *client)
>>>>>> +{
>>>>>> +    struct vic *vic = to_vic(client);
>>>>>> +    int err;
>>>>>> +
>>>>>> +    err = vic_load_firmware(vic);
>>>>>
>>>>> You can't invoke vic_load_firmware() while RPM is suspended. Either
>>>>> replace this with RPM get/put or do something else.
>>>
>>> Why not, I'm not seeing any HW accesses in vic_load_firmware? Although
>>> it looks like it might race with the vic_load_firmware call in
>>> vic_runtime_resume which probably needs to be fixed.
>>
>> It was not clear from the function's name that h/w is untouched, I read
>> "load" as "upload" and then looked at vic_runtime_resume(). I'd rename
>> vic_load_firmware() to vic_prepare_firmware_image().
>>
>> And yes, technically lock is needed.
> 
> Yep, I'll consider renaming it.

Looking at this all again, I'd suggest to change:

int get_streamid_offset(client)

to:

int get_streamid_offset(client, *offset)

and bail out if get_streamid_offset() returns error. It's never okay to
ignore errors.