[2/8] uapi: videodev2: Add V4L2_META_FMT_RK_ISP1_EXT_PARAMS
Commit Message
Add a new format definition for the RkISP1 extensible parameters
format and document it.
Document the usage of the new format in the rkisp1 admin guide.
Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
---
Documentation/admin-guide/media/rkisp1.rst | 11 +++-
.../media/v4l/metafmt-rkisp1.rst | 62 ++++++++++++++++---
drivers/media/v4l2-core/v4l2-ioctl.c | 1 +
include/uapi/linux/videodev2.h | 1 +
4 files changed, 64 insertions(+), 11 deletions(-)
Comments
Hi Jacopo
On 05/06/2024 17:54, Jacopo Mondi wrote:
> Add a new format definition for the RkISP1 extensible parameters
> format and document it.
>
> Document the usage of the new format in the rkisp1 admin guide.
>
> Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
> ---
> Documentation/admin-guide/media/rkisp1.rst | 11 +++-
> .../media/v4l/metafmt-rkisp1.rst | 62 ++++++++++++++++---
> drivers/media/v4l2-core/v4l2-ioctl.c | 1 +
> include/uapi/linux/videodev2.h | 1 +
> 4 files changed, 64 insertions(+), 11 deletions(-)
>
> diff --git a/Documentation/admin-guide/media/rkisp1.rst b/Documentation/admin-guide/media/rkisp1.rst
> index 6f14d9561fa5..934c25e191df 100644
> --- a/Documentation/admin-guide/media/rkisp1.rst
> +++ b/Documentation/admin-guide/media/rkisp1.rst
> @@ -114,11 +114,18 @@ to be applied to the hardware during a video stream, allowing userspace
> to dynamically modify values such as black level, cross talk corrections
> and others.
>
> -The buffer format is defined by struct :c:type:`rkisp1_params_cfg`, and
> -userspace should set
> +The ISP driver supports two different parameters configuration methods, the
> +`fixed parameters format` or the `extensible parameters format`.
> +
> +When using the `fixed parameters` method the buffer format is defined by struct
> +:c:type:`rkisp1_params_cfg`, and userspace set
> :ref:`V4L2_META_FMT_RK_ISP1_PARAMS <v4l2-meta-fmt-rk-isp1-params>` as the
> dataformat.
>
> +When using the fixed parameters method the buffer format is defined by struct
> +:c:type:`rkisp1_ext_params_cfg`, and userspace set
s/set/should set
> +:ref:`V4L2_META_FMT_RK_ISP1_EXT_PARAMS <v4l2-meta-fmt-rk-isp1-ext-params>` as
> +the dataformat.
>
> Capturing Video Frames Example
> ==============================
> diff --git a/Documentation/userspace-api/media/v4l/metafmt-rkisp1.rst b/Documentation/userspace-api/media/v4l/metafmt-rkisp1.rst
> index fa04f00bcd2e..6ff776d071a3 100644
> --- a/Documentation/userspace-api/media/v4l/metafmt-rkisp1.rst
> +++ b/Documentation/userspace-api/media/v4l/metafmt-rkisp1.rst
> @@ -1,28 +1,72 @@
> .. SPDX-License-Identifier: GPL-2.0
>
> -.. _v4l2-meta-fmt-rk-isp1-params:
> -
> .. _v4l2-meta-fmt-rk-isp1-stat-3a:
>
> -*****************************************************************************
> -V4L2_META_FMT_RK_ISP1_PARAMS ('rk1p'), V4L2_META_FMT_RK_ISP1_STAT_3A ('rk1s')
> -*****************************************************************************
> +************************************************************************************************************************
> +V4L2_META_FMT_RK_ISP1_PARAMS ('rk1p'), V4L2_META_FMT_RK_ISP1_STAT_3A ('rk1s'), V4L2_META_FMT_RK_ISP1_EXT_PARAMS ('rk1e')
> +************************************************************************************************************************
>
> +========================
> Configuration parameters
> ========================
>
> -The configuration parameters are passed to the
> +The configuration of the RkISP1 ISP is performed by userspace by providing
> +parameters for the ISP to the driver using the :c:type:`v4l2_meta_format`
> +interface.
> +
> +There are currently two methods that allow to configure the ISP, the `fixed
> +parameters` configuration format and the `extensible parameters` configuration
> +format.
> +
> +.. _v4l2-meta-fmt-rk-isp1-params:
> +
> +Fixed parameters configuration format
> +=====================================
> +
> +When using the fixed configuration format, parameters are passed to the
> :ref:`rkisp1_params <rkisp1_params>` metadata output video node, using
> -the :c:type:`v4l2_meta_format` interface. The buffer contains
> -a single instance of the C structure :c:type:`rkisp1_params_cfg` defined in
> -``rkisp1-config.h``. So the structure can be obtained from the buffer by:
> +the `V4L2_META_FMT_RK_ISP1_PARAMS` meta pixel format.
> +
> +The buffer contains a single instance of the C structure
> +:c:type:`rkisp1_params_cfg` defined in ``rkisp1-config.h``. So the structure can
> +be obtained from the buffer by:
>
> .. code-block:: c
>
> struct rkisp1_params_cfg *params = (struct rkisp1_params_cfg*) buffer;
>
> +As the members of :c:type:`rkisp1_params_cfg` are defined in the
> +``rkisp1-config.h`` header, the structure layout is immutable and cannot be
> +extended further. For this reason the fixed configuration format only allows the
> +configuration of the ISP blocks supported at the time when the structure had
> +been defined in the header file, as introducing new parameters or modifying the
> +existing ones would change the buffer layout and cause breakages in existing
> +applications.
I'm not sure I'd bother with the last sentence; up to you though. Possibly a quick explainer as to
why there's two separate methods and why the extensible one should be preferred could be in the
"Configuration parameters" section instead.
> +
> +.. _v4l2-meta-fmt-rk-isp1-ext-params:
> +
> +Extensible parameters configuration format
> +==========================================
> +
> +When using the extensible configuration format, parameters are passed to the
> +:ref:`rkisp1_params <rkisp1_params>` metadata output video node, using
> +the `V4L2_META_FMT_RK_ISP1_EXT_PARAMS` meta pixel format.
> +
> +The buffer contains a single instance of the C structure
> +:c:type:`rkisp1_ext_params_cfg` defined in ``rkisp1-config.h``. The
> +:c:type:`rkisp1_ext_params_cfg` structure is designed to allow userspace to
> +populate the data buffer with only the configuration data for the ISP block it
s/block/block(s)?
> +intends to configure. The extensible parameters format design allows to define
> +new block types and new configuration parameters and defines a versioning scheme
Perhaps "allows developers to define new block types to support new configuration parameters"?
> +so that it can be extended and versioned without breaking compatibility with
> +existing applications.
> +
> +For these reasons, this configuration method if preferred over the `fixed
> +parameters` format alternative.
> +
> .. rkisp1_stat_buffer
>
> +===========================
> 3A and histogram statistics
> ===========================
>
> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
> index 4c76d17b4629..aefdc1efd24b 100644
> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
> @@ -1456,6 +1456,7 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
> case V4L2_META_FMT_VIVID: descr = "Vivid Metadata"; break;
> case V4L2_META_FMT_RK_ISP1_PARAMS: descr = "Rockchip ISP1 3A Parameters"; break;
> case V4L2_META_FMT_RK_ISP1_STAT_3A: descr = "Rockchip ISP1 3A Statistics"; break;
> + case V4L2_META_FMT_RK_ISP1_EXT_PARAMS: descr = "Rockchip ISP1 Ext 3A Params"; break;
I think spell out "Extensible" personally; we already allow breaking like length limits here.
Reviewed-by: Daniel Scally <dan.scally@ideasonboard.com>
> case V4L2_PIX_FMT_NV12_8L128: descr = "NV12 (8x128 Linear)"; break;
> case V4L2_PIX_FMT_NV12M_8L128: descr = "NV12M (8x128 Linear)"; break;
> case V4L2_PIX_FMT_NV12_10BE_8L128: descr = "10-bit NV12 (8x128 Linear, BE)"; break;
> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
> index fe6b67e83751..7c2a303c6f59 100644
> --- a/include/uapi/linux/videodev2.h
> +++ b/include/uapi/linux/videodev2.h
> @@ -840,6 +840,7 @@ struct v4l2_pix_format {
> /* Vendor specific - used for RK_ISP1 camera sub-system */
> #define V4L2_META_FMT_RK_ISP1_PARAMS v4l2_fourcc('R', 'K', '1', 'P') /* Rockchip ISP1 3A Parameters */
> #define V4L2_META_FMT_RK_ISP1_STAT_3A v4l2_fourcc('R', 'K', '1', 'S') /* Rockchip ISP1 3A Statistics */
> +#define V4L2_META_FMT_RK_ISP1_EXT_PARAMS v4l2_fourcc('R', 'K', '1', 'E') /* Rockchip ISP1 3a Extensible Parameters */
>
> #ifdef __KERNEL__
> /*
On Wed, Jun 12, 2024 at 11:00:37AM +0100, Daniel Scally wrote:
> On 05/06/2024 17:54, Jacopo Mondi wrote:
> > Add a new format definition for the RkISP1 extensible parameters
> > format and document it.
> >
> > Document the usage of the new format in the rkisp1 admin guide.
> >
> > Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
> > ---
> > Documentation/admin-guide/media/rkisp1.rst | 11 +++-
> > .../media/v4l/metafmt-rkisp1.rst | 62 ++++++++++++++++---
> > drivers/media/v4l2-core/v4l2-ioctl.c | 1 +
> > include/uapi/linux/videodev2.h | 1 +
> > 4 files changed, 64 insertions(+), 11 deletions(-)
> >
> > diff --git a/Documentation/admin-guide/media/rkisp1.rst b/Documentation/admin-guide/media/rkisp1.rst
> > index 6f14d9561fa5..934c25e191df 100644
> > --- a/Documentation/admin-guide/media/rkisp1.rst
> > +++ b/Documentation/admin-guide/media/rkisp1.rst
> > @@ -114,11 +114,18 @@ to be applied to the hardware during a video stream, allowing userspace
> > to dynamically modify values such as black level, cross talk corrections
> > and others.
> >
> > -The buffer format is defined by struct :c:type:`rkisp1_params_cfg`, and
> > -userspace should set
> > +The ISP driver supports two different parameters configuration methods, the
> > +`fixed parameters format` or the `extensible parameters format`.
> > +
> > +When using the `fixed parameters` method the buffer format is defined by struct
> > +:c:type:`rkisp1_params_cfg`, and userspace set
> > :ref:`V4L2_META_FMT_RK_ISP1_PARAMS <v4l2-meta-fmt-rk-isp1-params>` as the
> > dataformat.
> >
> > +When using the fixed parameters method the buffer format is defined by struct
> > +:c:type:`rkisp1_ext_params_cfg`, and userspace set
>
> s/set/should set
Above too.
> > +:ref:`V4L2_META_FMT_RK_ISP1_EXT_PARAMS <v4l2-meta-fmt-rk-isp1-ext-params>` as
> > +the dataformat.
> >
> > Capturing Video Frames Example
> > ==============================
> > diff --git a/Documentation/userspace-api/media/v4l/metafmt-rkisp1.rst b/Documentation/userspace-api/media/v4l/metafmt-rkisp1.rst
> > index fa04f00bcd2e..6ff776d071a3 100644
> > --- a/Documentation/userspace-api/media/v4l/metafmt-rkisp1.rst
> > +++ b/Documentation/userspace-api/media/v4l/metafmt-rkisp1.rst
> > @@ -1,28 +1,72 @@
> > .. SPDX-License-Identifier: GPL-2.0
> >
> > -.. _v4l2-meta-fmt-rk-isp1-params:
> > -
> > .. _v4l2-meta-fmt-rk-isp1-stat-3a:
> >
> > -*****************************************************************************
> > -V4L2_META_FMT_RK_ISP1_PARAMS ('rk1p'), V4L2_META_FMT_RK_ISP1_STAT_3A ('rk1s')
> > -*****************************************************************************
> > +************************************************************************************************************************
> > +V4L2_META_FMT_RK_ISP1_PARAMS ('rk1p'), V4L2_META_FMT_RK_ISP1_STAT_3A ('rk1s'), V4L2_META_FMT_RK_ISP1_EXT_PARAMS ('rk1e')
> > +************************************************************************************************************************
> >
> > +========================
> > Configuration parameters
> > ========================
> >
> > -The configuration parameters are passed to the
> > +The configuration of the RkISP1 ISP is performed by userspace by providing
> > +parameters for the ISP to the driver using the :c:type:`v4l2_meta_format`
> > +interface.
> > +
> > +There are currently two methods that allow to configure the ISP, the `fixed
s/currently //
> > +parameters` configuration format and the `extensible parameters` configuration
> > +format.
> > +
> > +.. _v4l2-meta-fmt-rk-isp1-params:
> > +
> > +Fixed parameters configuration format
> > +=====================================
> > +
> > +When using the fixed configuration format, parameters are passed to the
> > :ref:`rkisp1_params <rkisp1_params>` metadata output video node, using
> > -the :c:type:`v4l2_meta_format` interface. The buffer contains
> > -a single instance of the C structure :c:type:`rkisp1_params_cfg` defined in
> > -``rkisp1-config.h``. So the structure can be obtained from the buffer by:
> > +the `V4L2_META_FMT_RK_ISP1_PARAMS` meta pixel format.
s/meta pixel format/meta format/ I think. Same below.
> > +
> > +The buffer contains a single instance of the C structure
> > +:c:type:`rkisp1_params_cfg` defined in ``rkisp1-config.h``. So the structure can
> > +be obtained from the buffer by:
> >
> > .. code-block:: c
> >
> > struct rkisp1_params_cfg *params = (struct rkisp1_params_cfg*) buffer;
> >
> > +As the members of :c:type:`rkisp1_params_cfg` are defined in the
> > +``rkisp1-config.h`` header, the structure layout is immutable and cannot be
> > +extended further. For this reason the fixed configuration format only allows the
> > +configuration of the ISP blocks supported at the time when the structure had
> > +been defined in the header file, as introducing new parameters or modifying the
> > +existing ones would change the buffer layout and cause breakages in existing
> > +applications.
>
> I'm not sure I'd bother with the last sentence; up to you though.
> Possibly a quick explainer as to why there's two separate methods and
> why the extensible one should be preferred could be in the
> "Configuration parameters" section instead.
I agree. The last sentence here belongs to a commit message more than to
the in-kernel documentation. I would replace it with "This method
supports a subset of the ISP features only, new applications should use
the extensible parameters method." or something similar.
> > +
> > +.. _v4l2-meta-fmt-rk-isp1-ext-params:
> > +
> > +Extensible parameters configuration format
> > +==========================================
> > +
> > +When using the extensible configuration format, parameters are passed to the
> > +:ref:`rkisp1_params <rkisp1_params>` metadata output video node, using
> > +the `V4L2_META_FMT_RK_ISP1_EXT_PARAMS` meta pixel format.
> > +
> > +The buffer contains a single instance of the C structure
> > +:c:type:`rkisp1_ext_params_cfg` defined in ``rkisp1-config.h``. The
> > +:c:type:`rkisp1_ext_params_cfg` structure is designed to allow userspace to
> > +populate the data buffer with only the configuration data for the ISP block it
>
> s/block/block(s)?
>
> > +intends to configure. The extensible parameters format design allows to define
> > +new block types and new configuration parameters and defines a versioning scheme
>
> Perhaps "allows developers to define new block types to support new configuration parameters"?
>
> > +so that it can be extended and versioned without breaking compatibility with
> > +existing applications.
> > +
> > +For these reasons, this configuration method if preferred over the `fixed
> > +parameters` format alternative.
> > +
> > .. rkisp1_stat_buffer
> >
> > +===========================
> > 3A and histogram statistics
> > ===========================
> >
> > diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
> > index 4c76d17b4629..aefdc1efd24b 100644
> > --- a/drivers/media/v4l2-core/v4l2-ioctl.c
> > +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
> > @@ -1456,6 +1456,7 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
> > case V4L2_META_FMT_VIVID: descr = "Vivid Metadata"; break;
> > case V4L2_META_FMT_RK_ISP1_PARAMS: descr = "Rockchip ISP1 3A Parameters"; break;
> > case V4L2_META_FMT_RK_ISP1_STAT_3A: descr = "Rockchip ISP1 3A Statistics"; break;
> > + case V4L2_META_FMT_RK_ISP1_EXT_PARAMS: descr = "Rockchip ISP1 Ext 3A Params"; break;
>
> I think spell out "Extensible" personally; we already allow breaking like length limits here.
Format descriptions are limited to 32 bytes in the UAPI :-(
> Reviewed-by: Daniel Scally <dan.scally@ideasonboard.com>
>
> > case V4L2_PIX_FMT_NV12_8L128: descr = "NV12 (8x128 Linear)"; break;
> > case V4L2_PIX_FMT_NV12M_8L128: descr = "NV12M (8x128 Linear)"; break;
> > case V4L2_PIX_FMT_NV12_10BE_8L128: descr = "10-bit NV12 (8x128 Linear, BE)"; break;
> > diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
> > index fe6b67e83751..7c2a303c6f59 100644
> > --- a/include/uapi/linux/videodev2.h
> > +++ b/include/uapi/linux/videodev2.h
> > @@ -840,6 +840,7 @@ struct v4l2_pix_format {
> > /* Vendor specific - used for RK_ISP1 camera sub-system */
> > #define V4L2_META_FMT_RK_ISP1_PARAMS v4l2_fourcc('R', 'K', '1', 'P') /* Rockchip ISP1 3A Parameters */
> > #define V4L2_META_FMT_RK_ISP1_STAT_3A v4l2_fourcc('R', 'K', '1', 'S') /* Rockchip ISP1 3A Statistics */
> > +#define V4L2_META_FMT_RK_ISP1_EXT_PARAMS v4l2_fourcc('R', 'K', '1', 'E') /* Rockchip ISP1 3a Extensible Parameters */
> >
> > #ifdef __KERNEL__
> > /*
On 12/06/2024 15:35, Laurent Pinchart wrote:
> On Wed, Jun 12, 2024 at 11:00:37AM +0100, Daniel Scally wrote:
>> On 05/06/2024 17:54, Jacopo Mondi wrote:
>>> Add a new format definition for the RkISP1 extensible parameters
>>> format and document it.
>>>
>>> Document the usage of the new format in the rkisp1 admin guide.
>>>
>>> Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
>>> ---
>>> Documentation/admin-guide/media/rkisp1.rst | 11 +++-
>>> .../media/v4l/metafmt-rkisp1.rst | 62 ++++++++++++++++---
>>> drivers/media/v4l2-core/v4l2-ioctl.c | 1 +
>>> include/uapi/linux/videodev2.h | 1 +
>>> 4 files changed, 64 insertions(+), 11 deletions(-)
>>>
>>> diff --git a/Documentation/admin-guide/media/rkisp1.rst b/Documentation/admin-guide/media/rkisp1.rst
>>> index 6f14d9561fa5..934c25e191df 100644
>>> --- a/Documentation/admin-guide/media/rkisp1.rst
>>> +++ b/Documentation/admin-guide/media/rkisp1.rst
>>> @@ -114,11 +114,18 @@ to be applied to the hardware during a video stream, allowing userspace
>>> to dynamically modify values such as black level, cross talk corrections
>>> and others.
>>>
>>> -The buffer format is defined by struct :c:type:`rkisp1_params_cfg`, and
>>> -userspace should set
>>> +The ISP driver supports two different parameters configuration methods, the
>>> +`fixed parameters format` or the `extensible parameters format`.
>>> +
>>> +When using the `fixed parameters` method the buffer format is defined by struct
>>> +:c:type:`rkisp1_params_cfg`, and userspace set
>>> :ref:`V4L2_META_FMT_RK_ISP1_PARAMS <v4l2-meta-fmt-rk-isp1-params>` as the
>>> dataformat.
>>>
>>> +When using the fixed parameters method the buffer format is defined by struct
>>> +:c:type:`rkisp1_ext_params_cfg`, and userspace set
>> s/set/should set
> Above too.
>
>>> +:ref:`V4L2_META_FMT_RK_ISP1_EXT_PARAMS <v4l2-meta-fmt-rk-isp1-ext-params>` as
>>> +the dataformat.
>>>
>>> Capturing Video Frames Example
>>> ==============================
>>> diff --git a/Documentation/userspace-api/media/v4l/metafmt-rkisp1.rst b/Documentation/userspace-api/media/v4l/metafmt-rkisp1.rst
>>> index fa04f00bcd2e..6ff776d071a3 100644
>>> --- a/Documentation/userspace-api/media/v4l/metafmt-rkisp1.rst
>>> +++ b/Documentation/userspace-api/media/v4l/metafmt-rkisp1.rst
>>> @@ -1,28 +1,72 @@
>>> .. SPDX-License-Identifier: GPL-2.0
>>>
>>> -.. _v4l2-meta-fmt-rk-isp1-params:
>>> -
>>> .. _v4l2-meta-fmt-rk-isp1-stat-3a:
>>>
>>> -*****************************************************************************
>>> -V4L2_META_FMT_RK_ISP1_PARAMS ('rk1p'), V4L2_META_FMT_RK_ISP1_STAT_3A ('rk1s')
>>> -*****************************************************************************
>>> +************************************************************************************************************************
>>> +V4L2_META_FMT_RK_ISP1_PARAMS ('rk1p'), V4L2_META_FMT_RK_ISP1_STAT_3A ('rk1s'), V4L2_META_FMT_RK_ISP1_EXT_PARAMS ('rk1e')
>>> +************************************************************************************************************************
>>>
>>> +========================
>>> Configuration parameters
>>> ========================
>>>
>>> -The configuration parameters are passed to the
>>> +The configuration of the RkISP1 ISP is performed by userspace by providing
>>> +parameters for the ISP to the driver using the :c:type:`v4l2_meta_format`
>>> +interface.
>>> +
>>> +There are currently two methods that allow to configure the ISP, the `fixed
> s/currently //
>
>>> +parameters` configuration format and the `extensible parameters` configuration
>>> +format.
>>> +
>>> +.. _v4l2-meta-fmt-rk-isp1-params:
>>> +
>>> +Fixed parameters configuration format
>>> +=====================================
>>> +
>>> +When using the fixed configuration format, parameters are passed to the
>>> :ref:`rkisp1_params <rkisp1_params>` metadata output video node, using
>>> -the :c:type:`v4l2_meta_format` interface. The buffer contains
>>> -a single instance of the C structure :c:type:`rkisp1_params_cfg` defined in
>>> -``rkisp1-config.h``. So the structure can be obtained from the buffer by:
>>> +the `V4L2_META_FMT_RK_ISP1_PARAMS` meta pixel format.
> s/meta pixel format/meta format/ I think. Same below.
>
>>> +
>>> +The buffer contains a single instance of the C structure
>>> +:c:type:`rkisp1_params_cfg` defined in ``rkisp1-config.h``. So the structure can
>>> +be obtained from the buffer by:
>>>
>>> .. code-block:: c
>>>
>>> struct rkisp1_params_cfg *params = (struct rkisp1_params_cfg*) buffer;
>>>
>>> +As the members of :c:type:`rkisp1_params_cfg` are defined in the
>>> +``rkisp1-config.h`` header, the structure layout is immutable and cannot be
>>> +extended further. For this reason the fixed configuration format only allows the
>>> +configuration of the ISP blocks supported at the time when the structure had
>>> +been defined in the header file, as introducing new parameters or modifying the
>>> +existing ones would change the buffer layout and cause breakages in existing
>>> +applications.
>> I'm not sure I'd bother with the last sentence; up to you though.
>> Possibly a quick explainer as to why there's two separate methods and
>> why the extensible one should be preferred could be in the
>> "Configuration parameters" section instead.
> I agree. The last sentence here belongs to a commit message more than to
> the in-kernel documentation. I would replace it with "This method
> supports a subset of the ISP features only, new applications should use
> the extensible parameters method." or something similar.
>
>>> +
>>> +.. _v4l2-meta-fmt-rk-isp1-ext-params:
>>> +
>>> +Extensible parameters configuration format
>>> +==========================================
>>> +
>>> +When using the extensible configuration format, parameters are passed to the
>>> +:ref:`rkisp1_params <rkisp1_params>` metadata output video node, using
>>> +the `V4L2_META_FMT_RK_ISP1_EXT_PARAMS` meta pixel format.
>>> +
>>> +The buffer contains a single instance of the C structure
>>> +:c:type:`rkisp1_ext_params_cfg` defined in ``rkisp1-config.h``. The
>>> +:c:type:`rkisp1_ext_params_cfg` structure is designed to allow userspace to
>>> +populate the data buffer with only the configuration data for the ISP block it
>> s/block/block(s)?
>>
>>> +intends to configure. The extensible parameters format design allows to define
>>> +new block types and new configuration parameters and defines a versioning scheme
>> Perhaps "allows developers to define new block types to support new configuration parameters"?
>>
>>> +so that it can be extended and versioned without breaking compatibility with
>>> +existing applications.
>>> +
>>> +For these reasons, this configuration method if preferred over the `fixed
>>> +parameters` format alternative.
>>> +
>>> .. rkisp1_stat_buffer
>>>
>>> +===========================
>>> 3A and histogram statistics
>>> ===========================
>>>
>>> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
>>> index 4c76d17b4629..aefdc1efd24b 100644
>>> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
>>> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
>>> @@ -1456,6 +1456,7 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
>>> case V4L2_META_FMT_VIVID: descr = "Vivid Metadata"; break;
>>> case V4L2_META_FMT_RK_ISP1_PARAMS: descr = "Rockchip ISP1 3A Parameters"; break;
>>> case V4L2_META_FMT_RK_ISP1_STAT_3A: descr = "Rockchip ISP1 3A Statistics"; break;
>>> + case V4L2_META_FMT_RK_ISP1_EXT_PARAMS: descr = "Rockchip ISP1 Ext 3A Params"; break;
>> I think spell out "Extensible" personally; we already allow breaking like length limits here.
> Format descriptions are limited to 32 bytes in the UAPI :-(
Today I learned!
>
>> Reviewed-by: Daniel Scally <dan.scally@ideasonboard.com>
>>
>>> case V4L2_PIX_FMT_NV12_8L128: descr = "NV12 (8x128 Linear)"; break;
>>> case V4L2_PIX_FMT_NV12M_8L128: descr = "NV12M (8x128 Linear)"; break;
>>> case V4L2_PIX_FMT_NV12_10BE_8L128: descr = "10-bit NV12 (8x128 Linear, BE)"; break;
>>> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
>>> index fe6b67e83751..7c2a303c6f59 100644
>>> --- a/include/uapi/linux/videodev2.h
>>> +++ b/include/uapi/linux/videodev2.h
>>> @@ -840,6 +840,7 @@ struct v4l2_pix_format {
>>> /* Vendor specific - used for RK_ISP1 camera sub-system */
>>> #define V4L2_META_FMT_RK_ISP1_PARAMS v4l2_fourcc('R', 'K', '1', 'P') /* Rockchip ISP1 3A Parameters */
>>> #define V4L2_META_FMT_RK_ISP1_STAT_3A v4l2_fourcc('R', 'K', '1', 'S') /* Rockchip ISP1 3A Statistics */
>>> +#define V4L2_META_FMT_RK_ISP1_EXT_PARAMS v4l2_fourcc('R', 'K', '1', 'E') /* Rockchip ISP1 3a Extensible Parameters */
>>>
>>> #ifdef __KERNEL__
>>> /*
On Wed, Jun 05, 2024 at 06:54:21PM +0200, Jacopo Mondi wrote:
> Add a new format definition for the RkISP1 extensible parameters
> format and document it.
>
> Document the usage of the new format in the rkisp1 admin guide.
>
> Signed-off-by: Jacopo Mondi <jacopo.mondi@ideasonboard.com>
> ---
> Documentation/admin-guide/media/rkisp1.rst | 11 +++-
> .../media/v4l/metafmt-rkisp1.rst | 62 ++++++++++++++++---
> drivers/media/v4l2-core/v4l2-ioctl.c | 1 +
> include/uapi/linux/videodev2.h | 1 +
> 4 files changed, 64 insertions(+), 11 deletions(-)
>
> diff --git a/Documentation/admin-guide/media/rkisp1.rst b/Documentation/admin-guide/media/rkisp1.rst
> index 6f14d9561fa5..934c25e191df 100644
> --- a/Documentation/admin-guide/media/rkisp1.rst
> +++ b/Documentation/admin-guide/media/rkisp1.rst
> @@ -114,11 +114,18 @@ to be applied to the hardware during a video stream, allowing userspace
> to dynamically modify values such as black level, cross talk corrections
> and others.
>
> -The buffer format is defined by struct :c:type:`rkisp1_params_cfg`, and
> -userspace should set
> +The ISP driver supports two different parameters configuration methods, the
> +`fixed parameters format` or the `extensible parameters format`.
> +
> +When using the `fixed parameters` method the buffer format is defined by struct
> +:c:type:`rkisp1_params_cfg`, and userspace set
> :ref:`V4L2_META_FMT_RK_ISP1_PARAMS <v4l2-meta-fmt-rk-isp1-params>` as the
> dataformat.
>
> +When using the fixed parameters method the buffer format is defined by struct
s/fixed/extensible/ ?
> +:c:type:`rkisp1_ext_params_cfg`, and userspace set
> +:ref:`V4L2_META_FMT_RK_ISP1_EXT_PARAMS <v4l2-meta-fmt-rk-isp1-ext-params>` as
> +the dataformat.
>
> Capturing Video Frames Example
> ==============================
> diff --git a/Documentation/userspace-api/media/v4l/metafmt-rkisp1.rst b/Documentation/userspace-api/media/v4l/metafmt-rkisp1.rst
> index fa04f00bcd2e..6ff776d071a3 100644
> --- a/Documentation/userspace-api/media/v4l/metafmt-rkisp1.rst
> +++ b/Documentation/userspace-api/media/v4l/metafmt-rkisp1.rst
> @@ -1,28 +1,72 @@
> .. SPDX-License-Identifier: GPL-2.0
>
> -.. _v4l2-meta-fmt-rk-isp1-params:
> -
> .. _v4l2-meta-fmt-rk-isp1-stat-3a:
>
> -*****************************************************************************
> -V4L2_META_FMT_RK_ISP1_PARAMS ('rk1p'), V4L2_META_FMT_RK_ISP1_STAT_3A ('rk1s')
> -*****************************************************************************
> +************************************************************************************************************************
> +V4L2_META_FMT_RK_ISP1_PARAMS ('rk1p'), V4L2_META_FMT_RK_ISP1_STAT_3A ('rk1s'), V4L2_META_FMT_RK_ISP1_EXT_PARAMS ('rk1e')
> +************************************************************************************************************************
>
> +========================
> Configuration parameters
> ========================
>
> -The configuration parameters are passed to the
> +The configuration of the RkISP1 ISP is performed by userspace by providing
> +parameters for the ISP to the driver using the :c:type:`v4l2_meta_format`
> +interface.
> +
> +There are currently two methods that allow to configure the ISP, the `fixed
> +parameters` configuration format and the `extensible parameters` configuration
> +format.
> +
> +.. _v4l2-meta-fmt-rk-isp1-params:
> +
> +Fixed parameters configuration format
> +=====================================
> +
> +When using the fixed configuration format, parameters are passed to the
> :ref:`rkisp1_params <rkisp1_params>` metadata output video node, using
> -the :c:type:`v4l2_meta_format` interface. The buffer contains
> -a single instance of the C structure :c:type:`rkisp1_params_cfg` defined in
> -``rkisp1-config.h``. So the structure can be obtained from the buffer by:
> +the `V4L2_META_FMT_RK_ISP1_PARAMS` meta pixel format.
> +
> +The buffer contains a single instance of the C structure
> +:c:type:`rkisp1_params_cfg` defined in ``rkisp1-config.h``. So the structure can
> +be obtained from the buffer by:
>
> .. code-block:: c
>
> struct rkisp1_params_cfg *params = (struct rkisp1_params_cfg*) buffer;
>
> +As the members of :c:type:`rkisp1_params_cfg` are defined in the
> +``rkisp1-config.h`` header, the structure layout is immutable and cannot be
> +extended further. For this reason the fixed configuration format only allows the
> +configuration of the ISP blocks supported at the time when the structure had
> +been defined in the header file, as introducing new parameters or modifying the
> +existing ones would change the buffer layout and cause breakages in existing
> +applications.
> +
> +.. _v4l2-meta-fmt-rk-isp1-ext-params:
> +
> +Extensible parameters configuration format
> +==========================================
> +
> +When using the extensible configuration format, parameters are passed to the
> +:ref:`rkisp1_params <rkisp1_params>` metadata output video node, using
> +the `V4L2_META_FMT_RK_ISP1_EXT_PARAMS` meta pixel format.
> +
> +The buffer contains a single instance of the C structure
> +:c:type:`rkisp1_ext_params_cfg` defined in ``rkisp1-config.h``. The
> +:c:type:`rkisp1_ext_params_cfg` structure is designed to allow userspace to
> +populate the data buffer with only the configuration data for the ISP block it
> +intends to configure. The extensible parameters format design allows to define
s/allows to define/allows defining/
> +new block types and new configuration parameters and defines a versioning scheme
s/parameters/parameters,/
Reviewed-by: Paul Elder <paul.elder@ideasonboard.com>
> +so that it can be extended and versioned without breaking compatibility with
> +existing applications.
> +
> +For these reasons, this configuration method if preferred over the `fixed
> +parameters` format alternative.
> +
> .. rkisp1_stat_buffer
>
> +===========================
> 3A and histogram statistics
> ===========================
>
> diff --git a/drivers/media/v4l2-core/v4l2-ioctl.c b/drivers/media/v4l2-core/v4l2-ioctl.c
> index 4c76d17b4629..aefdc1efd24b 100644
> --- a/drivers/media/v4l2-core/v4l2-ioctl.c
> +++ b/drivers/media/v4l2-core/v4l2-ioctl.c
> @@ -1456,6 +1456,7 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
> case V4L2_META_FMT_VIVID: descr = "Vivid Metadata"; break;
> case V4L2_META_FMT_RK_ISP1_PARAMS: descr = "Rockchip ISP1 3A Parameters"; break;
> case V4L2_META_FMT_RK_ISP1_STAT_3A: descr = "Rockchip ISP1 3A Statistics"; break;
> + case V4L2_META_FMT_RK_ISP1_EXT_PARAMS: descr = "Rockchip ISP1 Ext 3A Params"; break;
> case V4L2_PIX_FMT_NV12_8L128: descr = "NV12 (8x128 Linear)"; break;
> case V4L2_PIX_FMT_NV12M_8L128: descr = "NV12M (8x128 Linear)"; break;
> case V4L2_PIX_FMT_NV12_10BE_8L128: descr = "10-bit NV12 (8x128 Linear, BE)"; break;
> diff --git a/include/uapi/linux/videodev2.h b/include/uapi/linux/videodev2.h
> index fe6b67e83751..7c2a303c6f59 100644
> --- a/include/uapi/linux/videodev2.h
> +++ b/include/uapi/linux/videodev2.h
> @@ -840,6 +840,7 @@ struct v4l2_pix_format {
> /* Vendor specific - used for RK_ISP1 camera sub-system */
> #define V4L2_META_FMT_RK_ISP1_PARAMS v4l2_fourcc('R', 'K', '1', 'P') /* Rockchip ISP1 3A Parameters */
> #define V4L2_META_FMT_RK_ISP1_STAT_3A v4l2_fourcc('R', 'K', '1', 'S') /* Rockchip ISP1 3A Statistics */
> +#define V4L2_META_FMT_RK_ISP1_EXT_PARAMS v4l2_fourcc('R', 'K', '1', 'E') /* Rockchip ISP1 3a Extensible Parameters */
>
> #ifdef __KERNEL__
> /*
> --
> 2.45.1
>
@@ -114,11 +114,18 @@ to be applied to the hardware during a video stream, allowing userspace
to dynamically modify values such as black level, cross talk corrections
and others.
-The buffer format is defined by struct :c:type:`rkisp1_params_cfg`, and
-userspace should set
+The ISP driver supports two different parameters configuration methods, the
+`fixed parameters format` or the `extensible parameters format`.
+
+When using the `fixed parameters` method the buffer format is defined by struct
+:c:type:`rkisp1_params_cfg`, and userspace set
:ref:`V4L2_META_FMT_RK_ISP1_PARAMS <v4l2-meta-fmt-rk-isp1-params>` as the
dataformat.
+When using the fixed parameters method the buffer format is defined by struct
+:c:type:`rkisp1_ext_params_cfg`, and userspace set
+:ref:`V4L2_META_FMT_RK_ISP1_EXT_PARAMS <v4l2-meta-fmt-rk-isp1-ext-params>` as
+the dataformat.
Capturing Video Frames Example
==============================
@@ -1,28 +1,72 @@
.. SPDX-License-Identifier: GPL-2.0
-.. _v4l2-meta-fmt-rk-isp1-params:
-
.. _v4l2-meta-fmt-rk-isp1-stat-3a:
-*****************************************************************************
-V4L2_META_FMT_RK_ISP1_PARAMS ('rk1p'), V4L2_META_FMT_RK_ISP1_STAT_3A ('rk1s')
-*****************************************************************************
+************************************************************************************************************************
+V4L2_META_FMT_RK_ISP1_PARAMS ('rk1p'), V4L2_META_FMT_RK_ISP1_STAT_3A ('rk1s'), V4L2_META_FMT_RK_ISP1_EXT_PARAMS ('rk1e')
+************************************************************************************************************************
+========================
Configuration parameters
========================
-The configuration parameters are passed to the
+The configuration of the RkISP1 ISP is performed by userspace by providing
+parameters for the ISP to the driver using the :c:type:`v4l2_meta_format`
+interface.
+
+There are currently two methods that allow to configure the ISP, the `fixed
+parameters` configuration format and the `extensible parameters` configuration
+format.
+
+.. _v4l2-meta-fmt-rk-isp1-params:
+
+Fixed parameters configuration format
+=====================================
+
+When using the fixed configuration format, parameters are passed to the
:ref:`rkisp1_params <rkisp1_params>` metadata output video node, using
-the :c:type:`v4l2_meta_format` interface. The buffer contains
-a single instance of the C structure :c:type:`rkisp1_params_cfg` defined in
-``rkisp1-config.h``. So the structure can be obtained from the buffer by:
+the `V4L2_META_FMT_RK_ISP1_PARAMS` meta pixel format.
+
+The buffer contains a single instance of the C structure
+:c:type:`rkisp1_params_cfg` defined in ``rkisp1-config.h``. So the structure can
+be obtained from the buffer by:
.. code-block:: c
struct rkisp1_params_cfg *params = (struct rkisp1_params_cfg*) buffer;
+As the members of :c:type:`rkisp1_params_cfg` are defined in the
+``rkisp1-config.h`` header, the structure layout is immutable and cannot be
+extended further. For this reason the fixed configuration format only allows the
+configuration of the ISP blocks supported at the time when the structure had
+been defined in the header file, as introducing new parameters or modifying the
+existing ones would change the buffer layout and cause breakages in existing
+applications.
+
+.. _v4l2-meta-fmt-rk-isp1-ext-params:
+
+Extensible parameters configuration format
+==========================================
+
+When using the extensible configuration format, parameters are passed to the
+:ref:`rkisp1_params <rkisp1_params>` metadata output video node, using
+the `V4L2_META_FMT_RK_ISP1_EXT_PARAMS` meta pixel format.
+
+The buffer contains a single instance of the C structure
+:c:type:`rkisp1_ext_params_cfg` defined in ``rkisp1-config.h``. The
+:c:type:`rkisp1_ext_params_cfg` structure is designed to allow userspace to
+populate the data buffer with only the configuration data for the ISP block it
+intends to configure. The extensible parameters format design allows to define
+new block types and new configuration parameters and defines a versioning scheme
+so that it can be extended and versioned without breaking compatibility with
+existing applications.
+
+For these reasons, this configuration method if preferred over the `fixed
+parameters` format alternative.
+
.. rkisp1_stat_buffer
+===========================
3A and histogram statistics
===========================
@@ -1456,6 +1456,7 @@ static void v4l_fill_fmtdesc(struct v4l2_fmtdesc *fmt)
case V4L2_META_FMT_VIVID: descr = "Vivid Metadata"; break;
case V4L2_META_FMT_RK_ISP1_PARAMS: descr = "Rockchip ISP1 3A Parameters"; break;
case V4L2_META_FMT_RK_ISP1_STAT_3A: descr = "Rockchip ISP1 3A Statistics"; break;
+ case V4L2_META_FMT_RK_ISP1_EXT_PARAMS: descr = "Rockchip ISP1 Ext 3A Params"; break;
case V4L2_PIX_FMT_NV12_8L128: descr = "NV12 (8x128 Linear)"; break;
case V4L2_PIX_FMT_NV12M_8L128: descr = "NV12M (8x128 Linear)"; break;
case V4L2_PIX_FMT_NV12_10BE_8L128: descr = "10-bit NV12 (8x128 Linear, BE)"; break;
@@ -840,6 +840,7 @@ struct v4l2_pix_format {
/* Vendor specific - used for RK_ISP1 camera sub-system */
#define V4L2_META_FMT_RK_ISP1_PARAMS v4l2_fourcc('R', 'K', '1', 'P') /* Rockchip ISP1 3A Parameters */
#define V4L2_META_FMT_RK_ISP1_STAT_3A v4l2_fourcc('R', 'K', '1', 'S') /* Rockchip ISP1 3A Statistics */
+#define V4L2_META_FMT_RK_ISP1_EXT_PARAMS v4l2_fourcc('R', 'K', '1', 'E') /* Rockchip ISP1 3a Extensible Parameters */
#ifdef __KERNEL__
/*