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Date:   Thu, 23 Jun 2022 10:26:45 +0200
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Subject: Re: DMA-buf and uncached system memory
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To:     Thomas Zimmermann <tzimmermann@suse.de>,
        linux-media <linux-media@vger.kernel.org>,
        dri-devel <dri-devel@lists.freedesktop.org>,
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Cc:     "Sharma, Shashank" <Shashank.Sharma@amd.com>
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 <58e11013-01ab-8a2c-732e-860ae83a3df6@suse.de>
From:   =?UTF-8?Q?Christian_K=c3=b6nig?= <christian.koenig@amd.com>
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Am 23.06.22 um 10:13 schrieb Thomas Zimmermann:
> Hi Christian
>
> Am 15.02.21 um 09:58 schrieb Christian König:
>> Hi guys,
>>
>> we are currently working an Freesync and direct scan out from system 
>> memory on AMD APUs in A+A laptops.
>>
>> On problem we stumbled over is that our display hardware needs to 
>> scan out from uncached system memory and we currently don't have a 
>> way to communicate that through DMA-buf.
>>
>> For our specific use case at hand we are going to implement something 
>> driver specific, but the question is should we have something more 
>> generic for this?
>
> I had a patchset here that extends iosys-map (former dma-buf-map) with 
> caching information. I'll post a copy.

Oh, nice. But why on iosys-map? We need that per DMA-buf.

Thanks,
Christian.

>
> Sorry for being late to reply.
>
> Best regards
> Thomas
>
>>
>> After all the system memory access pattern is a PCIe extension and as 
>> such something generic.
>>
>> Regards,
>> Christian.
>> _______________________________________________
>> dri-devel mailing list
>> dri-devel@lists.freedesktop.org
>> https://lists.freedesktop.org/mailman/listinfo/dri-devel
>