From: "Otavio Salvador" <otavio.salvador@ossystems.com.br>
To: Carlos Rafael Giani <crg7475@mailbox.org>
Cc: meta-freescale@lists.yoctoproject.org
Subject: Re: [meta-freescale] Enabling ION with CMA heap on imx6
Date: Tue, 20 Oct 2020 08:31:21 -0300 [thread overview]
Message-ID: <CAP9ODKqf_6Yz8avbhWPdFCNrgNDAM2_6=bpi20d3xN4bDnQzEA@mail.gmail.com> (raw)
In-Reply-To: <1ec795f6-53b7-52c7-f2dc-05c39c2f0d03@mailbox.org>
Hello Carlos,
Em ter., 20 de out. de 2020 às 05:19, Carlos Rafael Giani via
lists.yoctoproject.org <crg7475=mailbox.org@lists.yoctoproject.org>
escreveu:
> On i.MX6 machines, it is currently not possible to use the ION
> allocator. However, there is no hardware limitation that requires ION to
> be disabled.
>
> If ION were enabled, with a CMA heap, then it would be possible for
> userspace to allocate DMA-BUF buffers. I could then enable the ion
> packageconfig in the libimxdmabuffer recipe.
>
> The defconfig only needs these additions:
>
> CONFIG_ION=y
> CONFIG_ION_SYSTEM_HEAP=y
> CONFIG_ION_CMA_HEAP=y
>
> I tried it out, worked fine.
>
> Using DMA-BUF for allocating physically contiguous memory (via CMA) is
> preferable over using other allocators (like the ones from the VPU, IPU
> etc.) since it allows for proper buffer sharing, ownership transfer, is
> based on FDs (though physical address are accessible via an NXP
> extension), and there are extensions in OpenCL, OpenGL etc. for
> importing DMA-BUF. V4L2 also has DMA-BUF support.
>
> Opinions?
Please prepare the PR for it; also see if i.MX8 couldn't also benefit from it.
--
Otavio Salvador O.S. Systems
http://www.ossystems.com.br http://code.ossystems.com.br
Mobile: +55 (53) 9 9981-7854 Mobile: +1 (347) 903-9750
next prev parent reply other threads:[~2020-10-20 11:31 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-10-20 8:19 Enabling ION with CMA heap on imx6 Carlos Rafael Giani
2020-10-20 11:31 ` Otavio Salvador [this message]
2020-10-20 17:11 ` [meta-freescale] " Carlos Rafael Giani
2020-10-20 11:38 ` Andrey Zhizhikin
2020-10-20 17:13 ` Carlos Rafael Giani
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