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author | Sakari Ailus <sakari.ailus@linux.intel.com> | 2018-12-13 04:36:51 -0500 |
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committer | Mauro Carvalho Chehab <mchehab+samsung@kernel.org> | 2018-12-17 15:03:52 -0500 |
commit | 5e44465ccf7a6f088a7e94856d49ebecda12083f (patch) | |
tree | 7082d88c59936a09f1debe9f789b2d0fd16c9025 /Documentation/media | |
parent | d0276a2b830301e2320a96b458973cfe2af0f610 (diff) | |
download | linux-stable-5e44465ccf7a6f088a7e94856d49ebecda12083f.tar.gz linux-stable-5e44465ccf7a6f088a7e94856d49ebecda12083f.tar.bz2 linux-stable-5e44465ccf7a6f088a7e94856d49ebecda12083f.zip |
media: staging/ipu3-imgu: Address documentation comments
Address comments on the documentation after Yong's original patch.
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Diffstat (limited to 'Documentation/media')
-rw-r--r-- | Documentation/media/uapi/v4l/pixfmt-meta-intel-ipu3.rst | 2 | ||||
-rw-r--r-- | Documentation/media/v4l-drivers/ipu3.rst | 343 |
2 files changed, 194 insertions, 151 deletions
diff --git a/Documentation/media/uapi/v4l/pixfmt-meta-intel-ipu3.rst b/Documentation/media/uapi/v4l/pixfmt-meta-intel-ipu3.rst index 8cd30ffbf8b8..dc871006b41a 100644 --- a/Documentation/media/uapi/v4l/pixfmt-meta-intel-ipu3.rst +++ b/Documentation/media/uapi/v4l/pixfmt-meta-intel-ipu3.rst @@ -175,4 +175,4 @@ video node in ``V4L2_BUF_TYPE_META_CAPTURE`` format. Intel IPU3 ImgU uAPI data types =============================== -.. kernel-doc:: include/uapi/linux/intel-ipu3.h +.. kernel-doc:: drivers/staging/media/ipu3/include/intel-ipu3.h diff --git a/Documentation/media/v4l-drivers/ipu3.rst b/Documentation/media/v4l-drivers/ipu3.rst index 045bf4222b1a..f89b51dafadd 100644 --- a/Documentation/media/v4l-drivers/ipu3.rst +++ b/Documentation/media/v4l-drivers/ipu3.rst @@ -9,196 +9,241 @@ Copyright |copy| 2018 Intel Corporation Introduction ============ -This file documents Intel IPU3 (3rd generation Image Processing Unit) Imaging -Unit driver located under drivers/media/pci/intel/ipu3. +This file documents the Intel IPU3 (3rd generation Image Processing Unit) +Imaging Unit drivers located under drivers/media/pci/intel/ipu3 (CIO2) as well +as under drivers/staging/media/ipu3 (ImgU). The Intel IPU3 found in certain Kaby Lake (as well as certain Sky Lake) -platforms (U/Y processor lines) is made up of two parts namely Imaging Unit -(ImgU) and CIO2 device (MIPI CSI2 receiver). +platforms (U/Y processor lines) is made up of two parts namely the Imaging Unit +(ImgU) and the CIO2 device (MIPI CSI2 receiver). -The CIO2 device receives the raw bayer data from the sensors and outputs the -frames in a format that is specific to IPU3 (for consumption by IPU3 ImgU). -CIO2 driver is available as drivers/media/pci/intel/ipu3/ipu3-cio2* and is -enabled through the CONFIG_VIDEO_IPU3_CIO2 config option. +The CIO2 device receives the raw Bayer data from the sensors and outputs the +frames in a format that is specific to the IPU3 (for consumption by the IPU3 +ImgU). The CIO2 driver is available as drivers/media/pci/intel/ipu3/ipu3-cio2* +and is enabled through the CONFIG_VIDEO_IPU3_CIO2 config option. The Imaging Unit (ImgU) is responsible for processing images captured -through IPU3 CIO2 device. The ImgU driver sources can be found under -drivers/media/pci/intel/ipu3 directory. The driver is enabled through the +by the IPU3 CIO2 device. The ImgU driver sources can be found under +drivers/staging/media/ipu3 directory. The driver is enabled through the CONFIG_VIDEO_IPU3_IMGU config option. -The two driver modules are named ipu3-csi2 and ipu3-imgu, respectively. +The two driver modules are named ipu3_csi2 and ipu3_imgu, respectively. -The driver has been tested on Kaby Lake platforms (U/Y processor lines). +The drivers has been tested on Kaby Lake platforms (U/Y processor lines). -The driver implements V4L2, Media controller and V4L2 sub-device interfaces. -Camera sensors that have CSI-2 bus, which are connected to the IPU3 CIO2 -device are supported. Support for lens and flash drivers depends on the -above sensors. +Both of the drivers implement V4L2, Media Controller and V4L2 sub-device +interfaces. The IPU3 CIO2 driver supports camera sensors connected to the CIO2 +MIPI CSI-2 interfaces through V4L2 sub-device sensor drivers. -ImgU device nodes -================= +CIO2 +==== -The ImgU is represented as two V4L2 subdevs, each of which provides a V4L2 -subdev interface to the user space. +The CIO2 is represented as a single V4L2 subdev, which provides a V4L2 subdev +interface to the user space. There is a video node for each CSI-2 receiver, +with a single media controller interface for the entire device. -Each V4L2 subdev represents a pipe, which can support a maximum of 2 -streams. A private ioctl can be used to configure the mode (video or still) -of the pipe. +The CIO2 contains four independent capture channel, each with its own MIPI CSI-2 +receiver and DMA engine. Each channel is modelled as a V4L2 sub-device exposed +to userspace as a V4L2 sub-device node and has two pads: -This helps to support advanced camera features like Continuous View Finder -(CVF) and Snapshot During Video(SDV). +.. tabularcolumns:: |p{0.8cm}|p{4.0cm}|p{4.0cm}| -CIO2 device -=========== +.. flat-table:: -The CIO2 is represented as a single V4L2 subdev, which provides a V4L2 subdev -interface to the user space. There is a video node for each CSI-2 receiver, -with a single media controller interface for the entire device. + * - pad + - direction + - purpose -Media controller ----------------- + * - 0 + - sink + - MIPI CSI-2 input, connected to the sensor subdev -The media device interface allows to configure the ImgU links, which defines -the behavior of the IPU3 firmware. + * - 1 + - source + - Raw video capture, connected to the V4L2 video interface -Device operation ----------------- +The V4L2 video interfaces model the DMA engines. They are exposed to userspace +as V4L2 video device nodes. -With IPU3, once the input video node ("ipu3-imgu 0/1":0, -in <entity>:<pad-number> format) is queued with buffer (in packed raw bayer -format), IPU3 ISP starts processing the buffer and produces the video output -in YUV format and statistics output on respective output nodes. The driver -is expected to have buffers ready for all of parameter, output and -statistics nodes, when input video node is queued with buffer. +Capturing frames in raw Bayer format +------------------------------------ -At a minimum, all of input, main output, 3A statistics and viewfinder -video nodes should be enabled for IPU3 to start image processing. +CIO2 MIPI CSI2 receiver is used to capture frames (in packed raw Bayer format) +from the raw sensors connected to the CSI2 ports. The captured frames are used +as input to the ImgU driver. -Each ImgU V4L2 subdev has the following set of video nodes. +Image processing using IPU3 ImgU requires tools such as raw2pnm [#f1]_, and +yavta [#f2]_ due to the following unique requirements and / or features specific +to IPU3. -input, output and viewfinder video nodes ----------------------------------------- +-- The IPU3 CSI2 receiver outputs the captured frames from the sensor in packed +raw Bayer format that is specific to IPU3. -The frames (in packed raw bayer format specific to IPU3) received by the -input video node is processed by the IPU3 Imaging Unit and is output to 2 -video nodes, with each targeting different purpose (main output and viewfinder -output). +-- Multiple video nodes have to be operated simultaneously. -Details on raw bayer format specific to IPU3 can be found as below. -Documentation/media/uapi/v4l/pixfmt-meta-intel-ipu3.rst +Let us take the example of ov5670 sensor connected to CSI2 port 0, for a +2592x1944 image capture. -The driver supports V4L2 Video Capture Interface as defined at :ref:`devices`. +Using the media contorller APIs, the ov5670 sensor is configured to send +frames in packed raw Bayer format to IPU3 CSI2 receiver. -Only the multi-planar API is supported. More details can be found at -:ref:`planar-apis`. +# This example assumes /dev/media0 as the CIO2 media device +export MDEV=/dev/media0 -parameters video node ---------------------- +# and that ov5670 sensor is connected to i2c bus 10 with address 0x36 -The parameter video node receives the ISP algorithm parameters that are used -to configure how the ISP algorithms process the image. +export SDEV=$(media-ctl -d $MDEV -e "ov5670 10-0036") -Details on raw bayer format specific to IPU3 can be found as below. -Documentation/media/uapi/v4l/pixfmt-meta-intel-ipu3.rst +# Establish the link for the media devices using media-ctl [#f3]_ +media-ctl -d $MDEV -l "ov5670:0 -> ipu3-csi2 0:0[1]" -3A statistics video node ------------------------- +# Set the format for the media devices +media-ctl -d $MDEV -V "ov5670:0 [fmt:SGRBG10/2592x1944]" -3A statistics video node is used by the ImgU driver to output the 3A (auto -focus, auto exposure and auto white balance) statistics for the frames that -are being processed by the ISP to user space applications. User space -applications can use this statistics data to arrive at desired algorithm -parameters for ISP. +media-ctl -d $MDEV -V "ipu3-csi2 0:0 [fmt:SGRBG10/2592x1944]" -CIO2 device nodes -================= +media-ctl -d $MDEV -V "ipu3-csi2 0:1 [fmt:SGRBG10/2592x1944]" -CIO2 is represented as a single V4L2 sub-device with a video node for each -CSI-2 receiver. The video node represents the DMA engine. +Once the media pipeline is configured, desired sensor specific settings +(such as exposure and gain settings) can be set, using the yavta tool. -Configuring the Intel IPU3 -========================== +e.g -The Intel IPU3 ImgU driver supports V4L2 interface. Using V4L2 ioctl calls, -the ISP can be configured and enabled. +yavta -w 0x009e0903 444 $SDEV -The IPU3 ImgU pipelines can be configured using media controller APIs, -defined at :ref:`media_controller`. +yavta -w 0x009e0913 1024 $SDEV -Capturing frames in raw bayer format ------------------------------------- +yavta -w 0x009e0911 2046 $SDEV -IPU3 MIPI CSI2 receiver is used to capture frames (in packed raw bayer -format) from the raw sensors connected to the CSI2 ports. The captured -frames are used as input to the ImgU driver. +Once the desired sensor settings are set, frame captures can be done as below. -Image processing using IPU3 ImgU requires tools such as v4l2n [#f1]_, -raw2pnm [#f1]_, and yavta [#f2]_ due to the following unique requirements -and / or features specific to IPU3. +e.g --- The IPU3 CSI2 receiver outputs the captured frames from the sensor in -packed raw bayer format that is specific to IPU3 +yavta --data-prefix -u -c10 -n5 -I -s2592x1944 --file=/tmp/frame-#.bin \ + -f IPU3_SGRBG10 $(media-ctl -d $MDEV -e "ipu3-cio2 0") --- Multiple video nodes have to be operated simultaneously +With the above command, 10 frames are captured at 2592x1944 resolution, with +sGRBG10 format and output as IPU3_SGRBG10 format. -Let us take the example of ov5670 sensor connected to CSI2 port 0, for a -2592x1944 image capture. +The captured frames are available as /tmp/frame-#.bin files. -Using the media contorller APIs, the ov5670 sensor is configured to send -frames in packed raw bayer format to IPU3 CSI2 receiver. +ImgU +==== -# This example assumes /dev/media0 as the ImgU media device +The ImgU is represented as two V4L2 subdevs, each of which provides a V4L2 +subdev interface to the user space. -export MDEV=/dev/media0 +Each V4L2 subdev represents a pipe, which can support a maximum of 2 streams. +This helps to support advanced camera features like Continuous View Finder (CVF) +and Snapshot During Video(SDV). -# and that ov5670 sensor is connected to i2c bus 10 with address 0x36 +The ImgU contains two independent pipes, each modelled as a V4L2 sub-device +exposed to userspace as a V4L2 sub-device node. -export SDEV="ov5670 10-0036" +Each pipe has two sink pads and three source pads for the following purpose: -# Establish the link for the media devices using media-ctl [#f3]_ -media-ctl -d $MDEV -l "ov5670 ":0 -> "ipu3-csi2 0":0[1] +.. tabularcolumns:: |p{0.8cm}|p{4.0cm}|p{4.0cm}| -media-ctl -d $MDEV -l "ipu3-csi2 0":1 -> "ipu3-cio2 0":0[1] +.. flat-table:: -# Set the format for the media devices -media-ctl -d $MDEV -V "ov5670 ":0 [fmt:SGRBG10/2592x1944] + * - pad + - direction + - purpose -media-ctl -d $MDEV -V "ipu3-csi2 0":0 [fmt:SGRBG10/2592x1944] + * - 0 + - sink + - Input raw video stream -media-ctl -d $MDEV -V "ipu3-csi2 0":1 [fmt:SGRBG10/2592x1944] + * - 1 + - sink + - Processing parameters -Once the media pipeline is configured, desired sensor specific settings -(such as exposure and gain settings) can be set, using the yavta tool. + * - 2 + - source + - Output processed video stream -e.g + * - 3 + - source + - Output viewfinder video stream -yavta -w 0x009e0903 444 $(media-ctl -d $MDEV -e "$SDEV") + * - 4 + - source + - 3A statistics -yavta -w 0x009e0913 1024 $(media-ctl -d $MDEV -e "$SDEV") +Each pad is connected to a corresponding V4L2 video interface, exposed to +userspace as a V4L2 video device node. + +Device operation +---------------- -yavta -w 0x009e0911 2046 $(media-ctl -d $MDEV -e "$SDEV") +With ImgU, once the input video node ("ipu3-imgu 0/1":0, in +<entity>:<pad-number> format) is queued with buffer (in packed raw Bayer +format), ImgU starts processing the buffer and produces the video output in YUV +format and statistics output on respective output nodes. The driver is expected +to have buffers ready for all of parameter, output and statistics nodes, when +input video node is queued with buffer. -Once the desired sensor settings are set, frame captures can be done as below. +At a minimum, all of input, main output, 3A statistics and viewfinder +video nodes should be enabled for IPU3 to start image processing. -e.g +Each ImgU V4L2 subdev has the following set of video nodes. -yavta --data-prefix -u -c10 -n5 -I -s2592x1944 --file=/tmp/frame-#.bin --f IPU3_GRBG10 media-ctl -d $MDEV -e ipu3-cio2 0 +input, output and viewfinder video nodes +---------------------------------------- -With the above command, 10 frames are captured at 2592x1944 resolution, with -sGRBG10 format and output as IPU3_GRBG10 format. +The frames (in packed raw Bayer format specific to the IPU3) received by the +input video node is processed by the IPU3 Imaging Unit and are output to 2 video +nodes, with each targeting a different purpose (main output and viewfinder +output). -The captured frames are available as /tmp/frame-#.bin files. +Details onand the Bayer format specific to the IPU3 can be found in +:ref:`v4l2-pix-fmt-ipu3-sbggr10`. -Processing the image in raw bayer format +The driver supports V4L2 Video Capture Interface as defined at :ref:`devices`. + +Only the multi-planar API is supported. More details can be found at +:ref:`planar-apis`. + +Parameters video node +--------------------- + +The parameters video node receives the ImgU algorithm parameters that are used +to configure how the ImgU algorithms process the image. + +Details on processing parameters specific to the IPU3 can be found in +:ref:`v4l2-meta-fmt-params`. + +3A statistics video node +------------------------ + +3A statistics video node is used by the ImgU driver to output the 3A (auto +focus, auto exposure and auto white balance) statistics for the frames that are +being processed by the ImgU to user space applications. User space applications +can use this statistics data to compute the desired algorithm parameters for +the ImgU. + +Configuring the Intel IPU3 +========================== + +The IPU3 ImgU pipelines can be configured using the Media Controller, defined at +:ref:`media_controller`. + +Firmware binary selection +------------------------- + +The firmware binary is selected using the V4L2_CID_INTEL_IPU3_MODE, currently +defined in drivers/staging/media/ipu3/include/intel-ipu3.h . "VIDEO" and "STILL" +modes are available. + +Processing the image in raw Bayer format ---------------------------------------- Configuring ImgU V4L2 subdev for image processing ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ -The ImgU V4L2 subdevs have to be configured with media controller APIs to -have all the video nodes setup correctly. +The ImgU V4L2 subdevs have to be configured with media controller APIs to have +all the video nodes setup correctly. Let us take "ipu3-imgu 0" subdev as an example. @@ -206,40 +251,38 @@ media-ctl -d $MDEV -r media-ctl -d $MDEV -l "ipu3-imgu 0 input":0 -> "ipu3-imgu 0":0[1] -media-ctl -d $MDEV -l "ipu3-imgu 0":2 -> "output":0[1] +media-ctl -d $MDEV -l "ipu3-imgu 0":2 -> "ipu3-imgu 0 output":0[1] -media-ctl -d $MDEV -l "ipu3-imgu 0":3 -> "viewfinder":0[1] +media-ctl -d $MDEV -l "ipu3-imgu 0":3 -> "ipu3-imgu 0 viewfinder":0[1] -media-ctl -d $MDEV -l "ipu3-imgu 0":4 -> "3a stat":0[1] +media-ctl -d $MDEV -l "ipu3-imgu 0":4 -> "ipu3-imgu 0 3a stat":0[1] -Also the pipe mode of the corresponding V4L2 subdev should be set as -desired (e.g 0 for video mode or 1 for still mode) through the -control id 0x009819a1 as below. - -e.g +Also the pipe mode of the corresponding V4L2 subdev should be set as desired +(e.g 0 for video mode or 1 for still mode) through the control id 0x009819a1 as +below. -v4l2n -d /dev/v4l-subdev7 --ctrl=0x009819A1=1 +yavta -w "0x009819A1 1" /dev/v4l-subdev7 -RAW bayer frames go through the following ISP pipeline HW blocks to -have the processed image output to the DDR memory. +RAW Bayer frames go through the following ImgU pipeline HW blocks to have the +processed image output to the DDR memory. -RAW bayer frame -> Input Feeder -> Bayer Down Scaling (BDS) -> Geometric +RAW Bayer frame -> Input Feeder -> Bayer Down Scaling (BDS) -> Geometric Distortion Correction (GDC) -> DDR -The ImgU V4L2 subdev has to be configured with the supported resolutions -in all the above HW blocks, for a given input resolution. +The ImgU V4L2 subdev has to be configured with the supported resolutions in all +the above HW blocks, for a given input resolution. -For a given supported resolution for an input frame, the Input Feeder, -Bayer Down Scaling and GDC blocks should be configured with the supported -resolutions. This information can be obtained by looking at the following -IPU3 ISP configuration table. +For a given supported resolution for an input frame, the Input Feeder, Bayer +Down Scaling and GDC blocks should be configured with the supported resolutions. +This information can be obtained by looking at the following IPU3 ImgU +configuration table. https://chromium.googlesource.com/chromiumos/overlays/board-overlays/+/master -Under baseboard-poppy/media-libs/arc-camera3-hal-configs-poppy/files/gcss +Under baseboard-poppy/media-libs/cros-camera-hal-configs-poppy/files/gcss directory, graph_settings_ov5670.xml can be used as an example. -The following steps prepare the ImgU ISP pipeline for the image processing. +The following steps prepare the ImgU pipeline for the image processing. 1. The ImgU V4L2 subdev data format should be set by using the VIDIOC_SUBDEV_S_FMT on pad 0, using the GDC width and height obtained above. @@ -257,14 +300,14 @@ For the ov5670 example, for an input frame with a resolution of 2592x1944 for input feeder, BDS and GDC are 2592x1944, 2592x1944 and 2560x1920 respectively. -Once this is done, the received raw bayer frames can be input to the ImgU -V4L2 subdev as below, using the open source application v4l2n. +Once this is done, the received raw Bayer frames can be input to the ImgU +V4L2 subdev as below, using the open source application v4l2n [#f1]_. For an image captured with 2592x1944 [#f4]_ resolution, with desired output resolution as 2560x1920 and viewfinder resolution as 2560x1920, the following -v4l2n command can be used. This helps process the raw bayer frames and -produces the desired results for the main output image and the viewfinder -output, in NV12 format. +v4l2n command can be used. This helps process the raw Bayer frames and produces +the desired results for the main output image and the viewfinder output, in NV12 +format. v4l2n --pipe=4 --load=/tmp/frame-#.bin --open=/dev/video4 --fmt=type:VIDEO_OUTPUT_MPLANE,width=2592,height=1944,pixelformat=0X47337069 @@ -281,7 +324,7 @@ v4l2n --pipe=4 --load=/tmp/frame-#.bin --open=/dev/video4 where /dev/video4, /dev/video5, /dev/video6 and /dev/video7 devices point to input, output, viewfinder and 3A statistics video nodes respectively. -Converting the raw bayer image into YUV domain +Converting the raw Bayer image into YUV domain ---------------------------------------------- The processed images after the above step, can be converted to YUV domain @@ -290,7 +333,7 @@ as below. Main output frames ~~~~~~~~~~~~~~~~~~ -raw2pnm -x2560 -y1920 -fNV12 /tmp/frames.out /tmp/frames.out.pnm +raw2pnm -x2560 -y1920 -fNV12 /tmp/frames.out /tmp/frames.out.ppm where 2560x1920 is output resolution, NV12 is the video format, followed by input frame and output PNM file. @@ -298,7 +341,7 @@ by input frame and output PNM file. Viewfinder output frames ~~~~~~~~~~~~~~~~~~~~~~~~ -raw2pnm -x2560 -y1920 -fNV12 /tmp/frames.vf /tmp/frames.vf.pnm +raw2pnm -x2560 -y1920 -fNV12 /tmp/frames.vf /tmp/frames.vf.ppm where 2560x1920 is output resolution, NV12 is the video format, followed by input frame and output PNM file. @@ -315,7 +358,7 @@ The source can be located under hal/intel directory. References ========== -include/uapi/linux/intel-ipu3.h +.. [#f5] include/uapi/linux/intel-ipu3.h .. [#f1] https://github.com/intel/nvt |