Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20;
MIME-Version: 1.0
References: <20221121214722.22563-1-umang.jain@ideasonboard.com> <Y3v4uZuhZTve2UI5@pendragon.ideasonboard.com>
In-Reply-To: <Y3v4uZuhZTve2UI5@pendragon.ideasonboard.com>
From:   Dave Stevenson <dave.stevenson@raspberrypi.com>
Date:   Tue, 22 Nov 2022 11:42:23 +0000
Message-ID: <CAPY8ntBrLvj_m_Rwt5SOjHypM5W3Foc6wRemFCcc1rpNQjMV0g@mail.gmail.com>
Subject: Re: [PATCH 00/14] staging: vc04_services: bcm2835-isp support
To:     Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Cc:     Umang Jain <umang.jain@ideasonboard.com>,
        linux-media@vger.kernel.org, kernel-list@raspberrypi.com,
        linux-kernel@vger.kernel.org, linux-rpi-kernel@lists.infradead.org,
        linux-arm-kernel@lists.infradead.org,
        linux-staging@lists.linux.dev,
        Broadcom internal kernel review list 
        <bcm-kernel-feedback-list@broadcom.com>,
        Florian Fainelli <f.fainelli@gmail.com>,
        Naushir Patuck <naush@raspberrypi.com>,
        David Plowman <david.plowman@raspberrypi.com>,
        Kieran Bingham <kieran.bingham@ideasonboard.com>
Content-Type: text/plain; charset="UTF-8"
Precedence: bulk

Hi Umang and Laurent

On Mon, 21 Nov 2022 at 22:16, Laurent Pinchart
<laurent.pinchart@ideasonboard.com> wrote:
>
> Hi Umang,
>
> Nice to see this series on the list !
>
> On Tue, Nov 22, 2022 at 03:17:08AM +0530, Umang Jain wrote:
> > This series aims to upport bcm2835-isp from the RPi kernel [1] and is a
> > independent subset of earlier series [2] posted to upport CSI-2/CCP2
> > receiver IP core("Unicam) + the ISP driver found in BCM283x and compatible
> > SoCs (namely BCM2711). Unicam is still under active development to work
> > with multistream support to get into mainline. Hence only the ISP driver
> > will remain the primary area of this series.
> >
> > Patch (01-02)/14  adds a new driver named vc-sm-cma to handle memory sharing
> > with the VC4 VPU.
> >
> > Patch 03/14 adds a small extension to videobuf2 to allow exporting as a
> > dma_buf instead of a file-descriptor.
> >
> > Patch (04-05)/14 adds a couple of improvements/support for
> > bcm2835-isp(event callback and zero-copy) to vchiq-mmal.
> >
> > Patch (06-09)/14 adds the core bcm2835-isp driver along with headers
> > and format defintions.
> >
> > Patch (10-11)/14 deals with the colorspace support.
> > Note: This is still WIP since the implementation of colorspace is still
> > getting ironed out (especially around setting of colorspace flags handling).
> >
> > Patch 12/14 allows multiple instances of the ISP.
> >
> > Patch 13/14 adds a admin-guide document on bcm2835-isp.
> >
> > Patch 14/14 wires all this up with the vchiq-mmal driver.
> >
> > Testing:
> > Tested with RPi Model 4B running linux mainline v6.1-rc6. To test
> > end-to-end, I choose to cherry-pick the Unicam patches and OV5647 DT
> > bindings from [1]). Once done, functional testing was conducted with
> > libcamera[3] and its utility tools.
> >
> > Also note: Reviews given on [2] for the relevant ISP driver patches have
> > been incorporated in this version.
> >
> > Known issues:
> > - Colorspace handling
>
> This will require further discussions, I'll try to comment on this topic
> in the review of the ISP driver patch.
>
> > - vc-sm-cma spamming kernel log with
> >       - pr_err("%s: Expecting an uncached alias for dma_addr %pad\n"
>
> Do you have any plan to address this ? Is the root cause known ?

You've picked up an old version of the downstream driver.
Pi0&1 share the VPU L2 cache with the ARM in the architecture, so they
use the 0x8 cache alias.
See https://github.com/raspberrypi/linux/commit/e22927f8ec9dc87772ac61d6aba00dc8046b4f49

  Dave

> > [1]: https://github.com/raspberrypi/linux
> > [2]: https://lore.kernel.org/linux-media/20200504092611.9798-1-laurent.pinchart@ideasonboard.com/
> > [3]: https://libcamera.org/getting-started.html
> >
> > Dave Stevenson (7):
> >   staging: vc04_services: Add new vc-sm-cma driver
> >   staging: vchiq_arm: Register vcsm-cma as a platform driver
> >   media: videobuf2: Allow exporting of a struct dmabuf
> >   staging: mmal-vchiq: Add support for event callbacks
> >   staging: mmal-vchiq: Use vc-sm-cma to support zero copy
> >   staging: mmal_vchiq: Add image formats to be used by bcm2835-isp
> >   uapi: bcm2835-isp: Add bcm2835-isp uapi header file
> >
> > David Plowman (2):
> >   vc04_services: bcm2835-isp: Allow formats with different colour spaces
> >   vc04_services: bcm2835-isp: Permit all sRGB colour spaces on ISP
> >     outputs
> >
> > Naushir Patuck (5):
> >   media: uapi: v4l2-core: Add ISP statistics output V4L2 fourcc type
> >   staging: vc04_services: bcm2835-isp: Add a more complex ISP processing
> >     component
> >   staging: vc04_services: bcm2835_isp: Allow multiple users
> >   docs: admin-guide: media: bcm2835-isp: Add documentation for
> >     bcm2835-isp
> >   staging: vc04_services: vchiq: Load bcm2835_isp driver from vchiq
> >
> >  .../admin-guide/media/bcm2835-isp.rst         |  127 ++
> >  .../userspace-api/media/drivers/index.rst     |    1 +
> >  .../userspace-api/media/v4l/meta-formats.rst  |    1 +
> >  .../v4l/pixfmt-meta-bcm2835-isp-stats.rst     |   41 +
> >  MAINTAINERS                                   |    9 +
> >  .../media/common/videobuf2/videobuf2-core.c   |   36 +-
> >  drivers/media/v4l2-core/v4l2-ioctl.c          |    1 +
> >  drivers/staging/vc04_services/Kconfig         |    4 +
> >  drivers/staging/vc04_services/Makefile        |    2 +
> >  .../staging/vc04_services/bcm2835-isp/Kconfig |   14 +
> >  .../vc04_services/bcm2835-isp/Makefile        |    8 +
> >  .../bcm2835-isp/bcm2835-isp-ctrls.h           |   72 +
> >  .../bcm2835-isp/bcm2835-isp-fmts.h            |  558 +++++
> >  .../bcm2835-isp/bcm2835-v4l2-isp.c            | 1817 +++++++++++++++++
> >  .../interface/vchiq_arm/vchiq_arm.c           |    6 +
> >  .../staging/vc04_services/vc-sm-cma/Kconfig   |   10 +
> >  .../staging/vc04_services/vc-sm-cma/Makefile  |   12 +
> >  .../staging/vc04_services/vc-sm-cma/vc_sm.c   |  801 ++++++++
> >  .../staging/vc04_services/vc-sm-cma/vc_sm.h   |   54 +
> >  .../vc04_services/vc-sm-cma/vc_sm_cma_vchi.c  |  507 +++++
> >  .../vc04_services/vc-sm-cma/vc_sm_cma_vchi.h  |   63 +
> >  .../vc04_services/vc-sm-cma/vc_sm_defs.h      |  187 ++
> >  .../vc04_services/vc-sm-cma/vc_sm_knl.h       |   28 +
> >  .../staging/vc04_services/vchiq-mmal/Kconfig  |    1 +
> >  .../vc04_services/vchiq-mmal/mmal-common.h    |    5 +
> >  .../vc04_services/vchiq-mmal/mmal-encodings.h |   66 +
> >  .../vc04_services/vchiq-mmal/mmal-msg.h       |   35 +
> >  .../vchiq-mmal/mmal-parameters.h              |  165 +-
> >  .../vc04_services/vchiq-mmal/mmal-vchiq.c     |  253 ++-
> >  .../vc04_services/vchiq-mmal/mmal-vchiq.h     |    5 +
> >  include/media/videobuf2-core.h                |   15 +
> >  include/uapi/linux/bcm2835-isp.h              |  347 ++++
> >  include/uapi/linux/v4l2-controls.h            |    6 +
> >  include/uapi/linux/videodev2.h                |    1 +
> >  34 files changed, 5225 insertions(+), 33 deletions(-)
> >  create mode 100644 Documentation/admin-guide/media/bcm2835-isp.rst
> >  create mode 100644 Documentation/userspace-api/media/v4l/pixfmt-meta-bcm2835-isp-stats.rst
> >  create mode 100644 drivers/staging/vc04_services/bcm2835-isp/Kconfig
> >  create mode 100644 drivers/staging/vc04_services/bcm2835-isp/Makefile
> >  create mode 100644 drivers/staging/vc04_services/bcm2835-isp/bcm2835-isp-ctrls.h
> >  create mode 100644 drivers/staging/vc04_services/bcm2835-isp/bcm2835-isp-fmts.h
> >  create mode 100644 drivers/staging/vc04_services/bcm2835-isp/bcm2835-v4l2-isp.c
> >  create mode 100644 drivers/staging/vc04_services/vc-sm-cma/Kconfig
> >  create mode 100644 drivers/staging/vc04_services/vc-sm-cma/Makefile
> >  create mode 100644 drivers/staging/vc04_services/vc-sm-cma/vc_sm.c
> >  create mode 100644 drivers/staging/vc04_services/vc-sm-cma/vc_sm.h
> >  create mode 100644 drivers/staging/vc04_services/vc-sm-cma/vc_sm_cma_vchi.c
> >  create mode 100644 drivers/staging/vc04_services/vc-sm-cma/vc_sm_cma_vchi.h
> >  create mode 100644 drivers/staging/vc04_services/vc-sm-cma/vc_sm_defs.h
> >  create mode 100644 drivers/staging/vc04_services/vc-sm-cma/vc_sm_knl.h
> >  create mode 100644 include/uapi/linux/bcm2835-isp.h
>
> --
> Regards,
>
> Laurent Pinchart