Re: [RFC PATCH V0 0/7] media: platform: Add support for Face Detection (FD) on mt8183 SoC

From: Hans Verkuil <hverkuil@xs4all.nl>
To: Jerry-ch Chen <Jerry-Ch.chen@mediatek.com>,
	hans.verkuil@cisco.com,
	laurent.pinchart+renesas@ideasonboard.com, tfiga@chromium.org,
	matthias.bgg@gmail.com, mchehab@kernel.org
Cc: devicetree@vger.kernel.org, Sean.Cheng@mediatek.com,
	Rynn.Wu@mediatek.com, srv_heupstream@mediatek.com,
	holmes.chiou@mediatek.com, jungo.lin@mediatek.com,
	sj.huang@mediatek.com, yuzhao@chromium.org,
	linux-mediatek@lists.infradead.org, zwisler@chromium.org,
	christie.yu@mediatek.com, frederic.chen@mediatek.com,
	linux-arm-kernel@lists.infradead.org,
	linux-media@vger.kernel.org
Subject: Re: [RFC PATCH V0 0/7] media: platform: Add support for Face Detection (FD) on mt8183 SoC
Date: Thu, 14 Mar 2019 09:40:49 +0100	[thread overview]
Message-ID: <1967d769-48c2-1d49-464a-6895cd2ff102@xs4all.nl> (raw)
In-Reply-To: <1550648893-42050-1-git-send-email-Jerry-Ch.chen@mediatek.com>

Hi Jerry-ch Chen,

On 2/20/19 8:48 AM, Jerry-ch Chen wrote:
> Hello,
> 
> This is the first version of the RFC patch series adding Face Detection
> (FD) driver on Mediatek mt8183 SoC, which will be used in camera features
> on CrOS application. It belongs to the first Mediatek's camera driver
> series based on V4L2 and media controller framework. I posted the main part
> of the FD driver as RFC to discuss first and would like some review
> comments on the overall structure of the driver.
> 
> Face Detection (FD) unit provide hardware accelerated face detection
> feature. It can detect different sizes of faces in a given image.
> Furthermore, it has the capability to detect the faces of Rotation-in-Plane
> from -180 to +180 degrees and Rotation-off-Plane from -90 to +90 degrees.
> 
> The driver is implemented with V4L2 and media controller framework. We have
> the following entities describing the FD path.

Just a high-level comment before you post the next version of this series:

Please compile the latest version of v4l2-compliance (part of
git://linuxtv.org/v4l-utils.git) and run it against your driver:

v4l2-compliance -m /dev/mediaX

Whenever you post a new version of this series, please do a 'git pull' of
the v4l-utils repo, recompile and retest with v4l2-compliance and post the
test results in the cover letter.

Obviously, there should be no FAILs and probably no warnings.

I suspect that streaming (e.g. adding the -s10 option to v4l2-compliance)
probably won't work since v4l2-compliance doesn't know about the meta data
formats.

Regards,

	Hans

> 
> 1. Meta input (output video device): connects to FD sub device. It accepts
>    the input parameter buffer from userspace. The metadata interface used
>    currently is only a temporary solution to kick off driver development
>    and is not ready for reviewed yet.
> 
> 2. RAW (output video device): connects to FD sub device. It accepts input
>    image buffer from userspace.
> 
> 3. FD (sub device): connects to Meta output. When processing an image,
>    FD hardware only returns the statistics of detected faces so it needs
>    only one capture video devices to return the streaming data to the user.
> 
> 4. Meta output (capture video device): Return the result of detected faces
>    as metadata output.
> 
>    The overall file structure of the FD driver is as following:
> 
> * mtk_fd-dev-ctx-core.c: Implements common software flow of FD driver.
> * mtk_fd-v4l2.c: Static FD contexts configuration.
> * mtk_fd.c: Controls the hardware flow.
> * mtk_fd-dev.c: Implements context-independent flow.
> * mtk_fd-ctrl.c: Handles the HW ctrl request from userspace.
> * mtk_fd-smem-drv.c: Provides the shared memory management required
> operation. We reserved a memory region for the co-processor and FD to
> exchange the hardware configuration data.
> * mtk_fd-v4l2-util.c: Implements V4L2 and vb2 ops.
> 
> Jerry-ch Chen (7):
>   dt-bindings: mt8183: Add binding for FD shared memory
>   dts: arm64: mt8183: Add FD shared memory node
>   dt-bindings: mt8183: Added FD-SMEM dt-bindings
>   dt-bindings: mt8183: Added FD dt-bindings
>   dts: arm64: mt8183: Add FD nodes
>   media: platform: Add Mediatek FD driver KConfig
>   platform: mtk-isp: Add Mediatek FD driver
> 
>  .../devicetree/bindings/media/mediatek,fd_smem.txt |   28 +
>  .../bindings/media/mediatek,mt8183-fd.txt          |   30 +
>  .../mediatek,reserve-memory-fd_smem.txt            |   44 +
>  arch/arm64/boot/dts/mediatek/mt8183.dtsi           |   28 +
>  drivers/media/platform/Kconfig                     |    2 +
>  drivers/media/platform/mtk-isp/Kconfig             |   10 +
>  drivers/media/platform/mtk-isp/Makefile            |   16 +
>  drivers/media/platform/mtk-isp/fd/Makefile         |   38 +
>  drivers/media/platform/mtk-isp/fd/mtk_fd-core.h    |  157 +++
>  drivers/media/platform/mtk-isp/fd/mtk_fd-ctx.h     |  299 ++++++
>  .../platform/mtk-isp/fd/mtk_fd-dev-ctx-core.c      |  917 +++++++++++++++++
>  drivers/media/platform/mtk-isp/fd/mtk_fd-dev.c     |  355 +++++++
>  drivers/media/platform/mtk-isp/fd/mtk_fd-dev.h     |  198 ++++
>  .../media/platform/mtk-isp/fd/mtk_fd-smem-drv.c    |  452 +++++++++
>  drivers/media/platform/mtk-isp/fd/mtk_fd-smem.h    |   25 +
>  .../media/platform/mtk-isp/fd/mtk_fd-v4l2-util.c   | 1046 ++++++++++++++++++++
>  drivers/media/platform/mtk-isp/fd/mtk_fd-v4l2.c    |  115 +++
>  drivers/media/platform/mtk-isp/fd/mtk_fd-v4l2.h    |   36 +
>  drivers/media/platform/mtk-isp/fd/mtk_fd.c         |  730 ++++++++++++++
>  drivers/media/platform/mtk-isp/fd/mtk_fd.h         |  127 +++
>  20 files changed, 4653 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/media/mediatek,fd_smem.txt
>  create mode 100644 Documentation/devicetree/bindings/media/mediatek,mt8183-fd.txt
>  create mode 100644 Documentation/devicetree/bindings/reserved-memory/mediatek,reserve-memory-fd_smem.txt
>  create mode 100644 drivers/media/platform/mtk-isp/Kconfig
>  create mode 100644 drivers/media/platform/mtk-isp/Makefile
>  create mode 100644 drivers/media/platform/mtk-isp/fd/Makefile
>  create mode 100644 drivers/media/platform/mtk-isp/fd/mtk_fd-core.h
>  create mode 100644 drivers/media/platform/mtk-isp/fd/mtk_fd-ctx.h
>  create mode 100644 drivers/media/platform/mtk-isp/fd/mtk_fd-dev-ctx-core.c
>  create mode 100644 drivers/media/platform/mtk-isp/fd/mtk_fd-dev.c
>  create mode 100644 drivers/media/platform/mtk-isp/fd/mtk_fd-dev.h
>  create mode 100644 drivers/media/platform/mtk-isp/fd/mtk_fd-smem-drv.c
>  create mode 100644 drivers/media/platform/mtk-isp/fd/mtk_fd-smem.h
>  create mode 100644 drivers/media/platform/mtk-isp/fd/mtk_fd-v4l2-util.c
>  create mode 100644 drivers/media/platform/mtk-isp/fd/mtk_fd-v4l2.c
>  create mode 100644 drivers/media/platform/mtk-isp/fd/mtk_fd-v4l2.h
>  create mode 100644 drivers/media/platform/mtk-isp/fd/mtk_fd.c
>  create mode 100644 drivers/media/platform/mtk-isp/fd/mtk_fd.h
> 