Merge tag 'media/v6.19-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media

digraph board {

        rankdir=TB

        n00000001 [label="{{} | mali-c55 tpg\n/dev/v4l-subdev0 | {<port0> 0}}", shape=Mrecord, style=filled, fillcolor=green]

        n00000001:port0 -> n00000003:port0 [style=dashed]

        n00000003 [label="{{<port0> 0} | mali-c55 isp\n/dev/v4l-subdev1 | {<port1> 1 | <port2> 2}}", shape=Mrecord, style=filled, fillcolor=green]

        n00000003:port1 -> n00000007:port0 [style=bold]

        n00000003:port2 -> n00000007:port2 [style=bold]

        n00000003:port1 -> n0000000b:port0 [style=bold]

        n00000007 [label="{{<port0> 0 | <port2> 2} | mali-c55 resizer fr\n/dev/v4l-subdev2 | {<port1> 1}}", shape=Mrecord, style=filled, fillcolor=green]

        n00000007:port1 -> n0000000e [style=bold]

        n0000000b [label="{{<port0> 0} | mali-c55 resizer ds\n/dev/v4l-subdev3 | {<port1> 1}}", shape=Mrecord, style=filled, fillcolor=green]

        n0000000b:port1 -> n00000012 [style=bold]

        n0000000e [label="mali-c55 fr\n/dev/video0", shape=box, style=filled, fillcolor=yellow]

        n00000012 [label="mali-c55 ds\n/dev/video1", shape=box, style=filled, fillcolor=yellow]

        n00000022 [label="{{<port0> 0} | csi2-rx\n/dev/v4l-subdev4 | {<port1> 1}}", shape=Mrecord, style=filled, fillcolor=green]

        n00000022:port1 -> n00000003:port0

        n00000027 [label="{{} | imx415 1-001a\n/dev/v4l-subdev5 | {<port0> 0}}", shape=Mrecord, style=filled, fillcolor=green]

        n00000027:port0 -> n00000022:port0 [style=bold]

}

 No newline at end of file

.. SPDX-License-Identifier: GPL-2.0

==========================================

ARM Mali-C55 Image Signal Processor driver

==========================================

Introduction

============

This file documents the driver for ARM's Mali-C55 Image Signal Processor. The

driver is located under drivers/media/platform/arm/mali-c55.

The Mali-C55 ISP receives data in either raw Bayer format or RGB/YUV format from

sensors through either a parallel interface or a memory bus before processing it

and outputting it through an internal DMA engine. Two output pipelines are

possible (though one may not be fitted, depending on the implementation). These

are referred to as "Full resolution" and "Downscale", but the naming is historic

and both pipes are capable of cropping/scaling operations. The full resolution

pipe is also capable of outputting RAW data, bypassing much of the ISP's

processing. The downscale pipe cannot output RAW data. An integrated test

pattern generator can be used to drive the ISP and produce image data in the

absence of a connected camera sensor. The driver module is named mali_c55, and

is enabled through the CONFIG_VIDEO_MALI_C55 config option.

The driver implements V4L2, Media Controller and V4L2 Subdevice interfaces and

expects camera sensors connected to the ISP to have V4L2 subdevice interfaces.

Mali-C55 ISP hardware

=====================

A high level functional view of the Mali-C55 ISP is presented below. The ISP

takes input from either a live source or through a DMA engine for memory input,

depending on the SoC integration.::

  +---------+    +----------+                                     +--------+

  | Sensor  |--->| CSI-2 Rx |                "Full Resolution"    |  DMA   |

  +---------+    +----------+   |\                 Output    +--->| Writer |

                       |        | \                          |    +--------+

                       |        |  \    +----------+  +------+---> Streaming I/O

  +------------+       +------->|   |   |          |  |

  |            |                |   |-->| Mali-C55 |--+

  | DMA Reader |--------------->|   |   |    ISP   |  |

  |            |                |  /    |          |  |      +---> Streaming I/O

  +------------+                | /     +----------+  |      |

                                |/                    +------+

                                                             |    +--------+

                                                             +--->|  DMA   |

                                               "Downscaled"       | Writer |

                                                  Output          +--------+

Media Controller Topology

=========================

An example of the ISP's topology (as implemented in a system with an IMX415

camera sensor and generic CSI-2 receiver) is below:

.. kernel-figure:: mali-c55-graph.dot

    :alt:   mali-c55-graph.dot

    :align: center

The driver has 4 V4L2 subdevices:

- `mali_c55 isp`: Responsible for configuring input crop and color space

                  conversion

- `mali_c55 tpg`: The test pattern generator, emulating a camera sensor.

- `mali_c55 resizer fr`: The Full-Resolution pipe resizer

- `mali_c55 resizer ds`: The Downscale pipe resizer

The driver has 3 V4L2 video devices:

- `mali-c55 fr`: The full-resolution pipe's capture device

- `mali-c55 ds`: The downscale pipe's capture device

- `mali-c55 3a stats`: The 3A statistics capture device

Frame sequences are synchronised across to two capture devices, meaning if one

pipe is started later than the other the sequence numbers returned in its

buffers will match those of the other pipe rather than starting from zero.

Idiosyncrasies

--------------

**mali-c55 isp**

The `mali-c55 isp` subdevice has a single sink pad to which all sources of data

should be connected. The active source is selected by enabling the appropriate

media link and disabling all others. The ISP has two source pads, reflecting the

different paths through which it can internally route data. Tap points within

the ISP allow users to divert data to avoid processing by some or all of the

hardware's processing steps. The diagram below is intended only to highlight how

the bypassing works and is not a true reflection of those processing steps; for

a high-level functional block diagram see ARM's developer page for the

ISP [3]_::

  +--------------------------------------------------------------+

  |                Possible Internal ISP Data Routes             |

  |          +------------+  +----------+  +------------+        |

  +---+      |            |  |          |  |  Colour    |    +---+

  | 0 |--+-->| Processing |->| Demosaic |->|   Space    |--->| 1 |

  +---+  |   |            |  |          |  | Conversion |    +---+

  |      |   +------------+  +----------+  +------------+        |

  |      |                                                   +---+

  |      +---------------------------------------------------| 2 |

  |                                                          +---+

  |                                                              |

  +--------------------------------------------------------------+

.. flat-table::

    :header-rows: 1

    * - Pad

      - Direction

      - Purpose

    * - 0

      - sink

      - Data input, connected to the TPG and camera sensors

    * - 1

      - source

      - RGB/YUV data, connected to the FR and DS V4L2 subdevices

    * - 2

      - source

      - RAW bayer data, connected to the FR V4L2 subdevices

The ISP is limited to both input and output resolutions between 640x480 and

8192x8192, and this is reflected in the ISP and resizer subdevice's .set_fmt()

operations.

**mali-c55 resizer fr**

The `mali-c55 resizer fr` subdevice has two _sink_ pads to reflect the different

insertion points in the hardware (either RAW or demosaiced data):

.. flat-table::

    :header-rows: 1

    * - Pad

      - Direction

      - Purpose

    * - 0

      - sink

      - Data input connected to the ISP's demosaiced stream.

    * - 1

      - source

      - Data output connected to the capture video device

    * - 2

      - sink

      - Data input connected to the ISP's raw data stream

The data source in use is selected through the routing API; two routes each of a

single stream are available:

.. flat-table::

    :header-rows: 1

    * - Sink Pad

      - Source Pad

      - Purpose

    * - 0

      - 1

      - Demosaiced data route

    * - 2

      - 1

      - Raw data route

If the demosaiced route is active then the FR pipe is only capable of output

in RGB/YUV formats. If the raw route is active then the output reflects the

input (which may be either Bayer or RGB/YUV data).

Using the driver to capture video

=================================

Using the media controller APIs we can configure the input source and ISP to

capture images in a variety of formats. In the examples below, configuring the

media graph is done with the v4l-utils [1]_ package's media-ctl utility.

Capturing the images is done with yavta [2]_.

Configuring the input source

----------------------------

The first step is to set the input source that we wish by enabling the correct

media link. Using the example topology above, we can select the TPG as follows:

.. code-block:: none

    media-ctl -l "'lte-csi2-rx':1->'mali-c55 isp':0[0]"

    media-ctl -l "'mali-c55 tpg':0->'mali-c55 isp':0[1]"

Configuring which video devices will stream data

------------------------------------------------

The driver will wait for all video devices to have their VIDIOC_STREAMON ioctl

called before it tells the sensor to start streaming. To facilitate this we need

to enable links to the video devices that we want to use. In the example below

we enable the links to both of the image capture video devices

.. code-block:: none

    media-ctl -l "'mali-c55 resizer fr':1->'mali-c55 fr':0[1]"

    media-ctl -l "'mali-c55 resizer ds':1->'mali-c55 ds':0[1]"

Capturing bayer data from the source and processing to RGB/YUV

--------------------------------------------------------------

To capture 1920x1080 bayer data from the source and push it through the ISP's

full processing pipeline, we configure the data formats appropriately on the

source, ISP and resizer subdevices and set the FR resizer's routing to select

processed data. The media bus format on the resizer's source pad will be either

RGB121212_1X36 or YUV10_1X30, depending on whether you want to capture RGB or

YUV. The ISP's debayering block outputs RGB data natively, setting the source

pad format to YUV10_1X30 enables the colour space conversion block.

In this example we target RGB565 output, so select RGB121212_1X36 as the resizer

source pad's format:

.. code-block:: none

    # Set formats on the TPG and ISP

    media-ctl -V "'mali-c55 tpg':0[fmt:SRGGB20_1X20/1920x1080]"

    media-ctl -V "'mali-c55 isp':0[fmt:SRGGB20_1X20/1920x1080]"

    media-ctl -V "'mali-c55 isp':1[fmt:SRGGB20_1X20/1920x1080]"

    # Set routing on the FR resizer

    media-ctl -R "'mali-c55 resizer fr'[0/0->1/0[1],2/0->1/0[0]]"

    # Set format on the resizer, must be done AFTER the routing.

    media-ctl -V "'mali-c55 resizer fr':1[fmt:RGB121212_1X36/1920x1080]"

The downscale output can also be used to stream data at the same time. In this

case since only processed data can be captured through the downscale output no

routing need be set:

.. code-block:: none

    # Set format on the resizer

    media-ctl -V "'mali-c55 resizer ds':1[fmt:RGB121212_1X36/1920x1080]"

Following which images can be captured from both the FR and DS output's video

devices (simultaneously, if desired):

.. code-block:: none

    yavta -f RGB565 -s 1920x1080 -c10 /dev/video0

    yavta -f RGB565 -s 1920x1080 -c10 /dev/video1

Cropping the image

~~~~~~~~~~~~~~~~~~

Both the full resolution and downscale pipes can crop to a minimum resolution of

640x480. To crop the image simply configure the resizer's sink pad's crop and

compose rectangles and set the format on the video device:

.. code-block:: none

    media-ctl -V "'mali-c55 resizer fr':0[fmt:RGB121212_1X36/1920x1080 crop:(480,270)/640x480 compose:(0,0)/640x480]"

    media-ctl -V "'mali-c55 resizer fr':1[fmt:RGB121212_1X36/640x480]"

    yavta -f RGB565 -s 640x480 -c10 /dev/video0

Downscaling the image

~~~~~~~~~~~~~~~~~~~~~

Both the full resolution and downscale pipes can downscale the image by up to 8x

provided the minimum 640x480 output resolution is adhered to. For the best image

result the scaling ratio for each direction should be the same. To configure

scaling we use the compose rectangle on the resizer's sink pad:

.. code-block:: none

    media-ctl -V "'mali-c55 resizer fr':0[fmt:RGB121212_1X36/1920x1080 crop:(0,0)/1920x1080 compose:(0,0)/640x480]"

    media-ctl -V "'mali-c55 resizer fr':1[fmt:RGB121212_1X36/640x480]"

    yavta -f RGB565 -s 640x480 -c10 /dev/video0

Capturing images in YUV formats

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

If we need to output YUV data rather than RGB the color space conversion block

needs to be active, which is achieved by setting MEDIA_BUS_FMT_YUV10_1X30 on the

resizer's source pad. We can then configure a capture format like NV12 (here in

its multi-planar variant)

.. code-block:: none

    media-ctl -V "'mali-c55 resizer fr':1[fmt:YUV10_1X30/1920x1080]"

    yavta -f NV12M -s 1920x1080 -c10 /dev/video0

Capturing RGB data from the source and processing it with the resizers

----------------------------------------------------------------------

The Mali-C55 ISP can work with sensors capable of outputting RGB data. In this

case although none of the image quality blocks would be used it can still

crop/scale the data in the usual way. For this reason RGB data input to the ISP

still goes through the ISP subdevice's pad 1 to the resizer.

To achieve this, the ISP's sink pad's format is set to

MEDIA_BUS_FMT_RGB202020_1X60 - this reflects the format that data must be in to

work with the ISP. Converting the camera sensor's output to that format is the

responsibility of external hardware.

In this example we ask the test pattern generator to give us RGB data instead of

bayer.

.. code-block:: none

    media-ctl -V "'mali-c55 tpg':0[fmt:RGB202020_1X60/1920x1080]"

    media-ctl -V "'mali-c55 isp':0[fmt:RGB202020_1X60/1920x1080]"

Cropping or scaling the data can be done in exactly the same way as outlined

earlier.

Capturing raw data from the source and outputting it unmodified

-----------------------------------------------------------------

The ISP can additionally capture raw data from the source and output it on the

full resolution pipe only, completely unmodified. In this case the downscale

pipe can still process the data normally and be used at the same time.

To configure raw bypass the FR resizer's subdevice's routing table needs to be

configured, followed by formats in the appropriate places:

.. code-block:: none

    media-ctl -R "'mali-c55 resizer fr'[0/0->1/0[0],2/0->1/0[1]]"

    media-ctl -V "'mali-c55 isp':0[fmt:RGB202020_1X60/1920x1080]"

    media-ctl -V "'mali-c55 resizer fr':2[fmt:RGB202020_1X60/1920x1080]"

    media-ctl -V "'mali-c55 resizer fr':1[fmt:RGB202020_1X60/1920x1080]"

    # Set format on the video device and stream

    yavta -f RGB565 -s 1920x1080 -c10 /dev/video0

.. _mali-c55-3a-stats:

Capturing ISP Statistics

========================

The ISP is capable of producing statistics for consumption by image processing

algorithms running in userspace. These statistics can be captured by queueing

buffers to the `mali-c55 3a stats` V4L2 Device whilst the ISP is streaming. Only

the :ref:`V4L2_META_FMT_MALI_C55_STATS <v4l2-meta-fmt-mali-c55-stats>`

format is supported, so no format-setting need be done:

.. code-block:: none

    # We assume the media graph has been configured to support RGB565 capture

    # from the mali-c55 fr V4L2 Device, which is at /dev/video0. The statistics

    # V4L2 device is at /dev/video3

    yavta -f RGB565 -s 1920x1080 -c32 /dev/video0 && \

    yavta -c10 -F /dev/video3

The layout of the buffer is described by :c:type:`mali_c55_stats_buffer`,

but broadly statistics are generated to support three image processing

algorithms; AEXP (Auto-Exposure), AWB (Auto-White Balance) and AF (Auto-Focus).

These stats can be drawn from various places in the Mali C55 ISP pipeline, known

as "tap points". This high-level block diagram is intended to explain where in

the processing flow the statistics can be drawn from::

                  +--> AEXP-2            +----> AEXP-1          +--> AF-0

                  |                      +----> AF-1            |

                  |                      |                      |

      +---------+ |   +--------------+   |   +--------------+   |

      |  Input  +-+-->+ Digital Gain +---+-->+ Black Level  +---+---+

      +---------+     +--------------+       +--------------+       |

  +-----------------------------------------------------------------+

  |

  |   +--------------+ +---------+       +----------------+

  +-->| Sinter Noise +-+  White  +--+--->|  Lens Shading  +--+---------------+

      |   Reduction  | | Balance |  |    |                |  |               |

      +--------------+ +---------+  |    +----------------+  |               |

                                    +---> AEXP-0 (A)         +--> AEXP-0 (B) |

  +--------------------------------------------------------------------------+

  |

  |   +----------------+      +--------------+  +----------------+

  +-->|  Tone mapping  +-+--->| Demosaicing  +->+ Purple Fringe  +-+-----------+

      |                | |    +--------------+  |   Correction   | |           |

      +----------------+ +-> AEXP-IRIDIX        +----------------+ +---> AWB-0 |

  +----------------------------------------------------------------------------+

  |                    +-------------+        +-------------+

  +------------------->|   Colour    +---+--->|    Output   |

                       | Correction  |   |    |  Pipelines  |

                       +-------------+   |    +-------------+

                                         +-->  AWB-1

By default all statistics are drawn from the 0th tap point for each algorithm;

I.E. AEXP statistics from AEXP-0 (A), AWB statistics from AWB-0 and AF

statistics from AF-0. This is configurable for AEXP and AWB statsistics through

programming the ISP's parameters.

.. _mali-c55-3a-params:

Programming ISP Parameters

==========================

The ISP can be programmed with various parameters from userspace to apply to the

hardware before and during video stream. This allows userspace to dynamically

change values such as black level, white balance and lens shading gains and so

on.

The buffer format and how to populate it are described by the

:ref:`V4L2_META_FMT_MALI_C55_PARAMS <v4l2-meta-fmt-mali-c55-params>` format,

which should be set as the data format for the `mali-c55 3a params` video node.

References

==========

.. [1] https://git.linuxtv.org/v4l-utils.git/

.. [2] https://git.ideasonboard.org/yavta.git

.. [3] https://developer.arm.com/Processors/Mali-C55

aspeed-video       Aspeed AST2400 and AST2500

atmel-isc          ATMEL Image Sensor Controller (ISC)

atmel-isi          ATMEL Image Sensor Interface (ISI)

c8sectpfe          SDR platform devices

c8sectpfe          SDR platform devices

cafe_ccic          Marvell 88ALP01 (Cafe) CMOS Camera Controller

cdns-csi2rx        Cadence MIPI-CSI2 RX Controller

cdns-csi2tx        Cadence MIPI-CSI2 TX Controller

digraph board {

        rankdir=TB

        n00000001 [label="{{<port0> 0} | rkcif-dvp0\n/dev/v4l-subdev0 | {<port1> 1}}", shape=Mrecord, style=filled, fillcolor=green]

        n00000001:port1 -> n00000004

        n00000004 [label="rkcif-dvp0-id0\n/dev/video0", shape=box, style=filled, fillcolor=yellow]

        n00000025 [label="{{} | it6801 2-0048\n/dev/v4l-subdev1 | {<port0> 0}}", shape=Mrecord, style=filled, fillcolor=green]

        n00000025:port0 -> n00000001:port0

}

.. SPDX-License-Identifier: GPL-2.0

=========================================

Rockchip Camera Interface (CIF)

=========================================

Introduction

============

The Rockchip Camera Interface (CIF) is featured in many Rockchip SoCs in

different variants.

The different variants are combinations of common building blocks, such as

* INTERFACE blocks of different types, namely

  * the Digital Video Port (DVP, a parallel data interface)

  * the interface block for the MIPI CSI-2 receiver

* CROP units

* MIPI CSI-2 receiver (not available on all variants): This unit is referred

  to as MIPI CSI HOST in the Rockchip documentation.

  Technically, it is a separate hardware block, but it is strongly coupled to

  the CIF and therefore included here.

* MUX units (not available on all variants) that pass the video data to an

  image signal processor (ISP)

* SCALE units (not available on all variants)

* DMA engines that transfer video data into system memory using a

  double-buffering mechanism called ping-pong mode

* Support for four streams per INTERFACE block (not available on all

  variants), e.g., for MIPI CSI-2 Virtual Channels (VCs)

This document describes the different variants of the CIF, their hardware

layout, as well as their representation in the media controller centric rkcif

device driver, which is located under drivers/media/platform/rockchip/rkcif.

Variants

========

Rockchip PX30 Video Input Processor (VIP)

-----------------------------------------

The PX30 Video Input Processor (VIP) features a digital video port that accepts

parallel video data or BT.656.

Since these protocols do not feature multiple streams, the VIP has one DMA

engine that transfers the input video data into system memory.

The rkcif driver represents this hardware variant by exposing one V4L2 subdevice

(the DVP INTERFACE/CROP block) and one V4L2 device (the DVP DMA engine).

Rockchip RK3568 Video Capture (VICAP)

-------------------------------------

The RK3568 Video Capture (VICAP) unit features a digital video port and a MIPI

CSI-2 receiver that can receive video data independently.

The DVP accepts parallel video data, BT.656 and BT.1120.

Since the BT.1120 protocol may feature more than one stream, the RK3568 VICAP

DVP features four DMA engines that can capture different streams.

Similarly, the RK3568 VICAP MIPI CSI-2 receiver features four DMA engines to

handle different Virtual Channels (VCs).

The rkcif driver represents this hardware variant by exposing up the following

V4L2 subdevices:

* rkcif-dvp0: INTERFACE/CROP block for the DVP

and the following video devices:

* rkcif-dvp0-id0: The support for multiple streams on the DVP is not yet

  implemented, as it is hard to find test hardware. Thus, this video device

  represents the first DMA engine of the RK3568 DVP.

.. kernel-figure:: rkcif-rk3568-vicap.dot

    :alt:   Topology of the RK3568 Video Capture (VICAP) unit

    :align: center