答复: [PATCH v2 3/4] [NOT FOR REVIEW] videobuf2-dc: Let drivers specify DMA attrs

Jun Zhao jung.zhao at rock-chips.com
Wed Feb 17 17:08:39 PST 2016


Hi Doug,
Thanks for your work. I will fix this mistake.

Best regards,
Jung

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福州瑞芯微电子有限公司 (Rockchip)
赵俊 (Jung Zhao)
算法工程师 (Algorithm Engineer)
+86-591-83991906-8944
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-----邮件原件-----
发件人: dianders at google.com [mailto:dianders at google.com] 代表 Doug Anderson
发送时间: 2016年2月18日 0:12
收件人: Jung Zhao
抄送: Tomasz Figa; Pawel Osciak; Mauro Carvalho Chehab; Hans Verkuil; Laurent Pinchart; Guennadi Liakhovetski; Philipp Zabel; open list:ARM/Rockchip SoC...; Linux Media Mailing List
主题: Re: [PATCH v2 3/4] [NOT FOR REVIEW] videobuf2-dc: Let drivers specify DMA attrs

Hi,

On Wed, Feb 17, 2016 at 2:42 AM, Jung Zhao <jung.zhao at rock-chips.com> wrote:
> From: Tomasz Figa <tfiga at chromium.org>
>
> DMA allocations might be subject to certain reqiurements specific to the
> hardware using the buffers, such as availability of kernel mapping (for
> contents fix-ups in the driver). The only entity that knows them is the
> driver, so it must share this knowledge with vb2-dc.
>
> This patch extends the alloc_ctx initialization interface to let the
> driver specify DMA attrs, which are then stored inside the allocation
> context and will be used for all allocations with that context.
>
> As a side effect, all dma_*_coherent() calls are turned into
> dma_*_attrs() calls, because the attributes need to be carried over
> through all DMA operations.
>
> Signed-off-by: Tomasz Figa <tfiga at chromium.org>
> Signed-off-by: Jung Zhao <jung.zhao at rock-chips.com>
> ---
> Changes in v2: None
>
>  drivers/media/v4l2-core/videobuf2-dma-contig.c | 33 +++++++++++++++++---------
>  include/media/videobuf2-dma-contig.h           | 11 ++++++++-
>  2 files changed, 32 insertions(+), 12 deletions(-)

This patch is already present in linuxnext.  I submitted it to Russell
King's Patch Tracking System a bit ago and got notice that it landed.
Checking linuxnext today I see:

ccc66e738252 ARM: 8508/2: videobuf2-dc: Let drivers specify DMA attrs

-Doug






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