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[2604:1380:4601:e00::3]) by mx.google.com with ESMTPS id o5-20020a170906288500b00a522ef880d4si7665740ejd.559.2024.04.23.19.50.32 for (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 23 Apr 2024 19:50:32 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel+bounces-156170-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:4601:e00::3 as permitted sender) client-ip=2604:1380:4601:e00::3; Authentication-Results: mx.google.com; arc=pass (i=1 spf=pass spfdomain=toshiba.co.jp dmarc=pass fromdomain=toshiba.co.jp); spf=pass (google.com: domain of linux-kernel+bounces-156170-linux.lists.archive=gmail.com@vger.kernel.org designates 2604:1380:4601:e00::3 as permitted sender) smtp.mailfrom="linux-kernel+bounces-156170-linux.lists.archive=gmail.com@vger.kernel.org"; dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=toshiba.co.jp Received: from smtp.subspace.kernel.org (wormhole.subspace.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by am.mirrors.kernel.org (Postfix) with ESMTPS id B76D81F24508 for ; Wed, 24 Apr 2024 02:50:31 +0000 (UTC) Received: from localhost.localdomain (localhost.localdomain [127.0.0.1]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 09E19143C5B; Wed, 24 Apr 2024 02:48:19 +0000 (UTC) Received: from mo-csw.securemx.jp (mo-csw1801.securemx.jp [210.130.202.135]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3150112FB38; Wed, 24 Apr 2024 02:48:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=210.130.202.135 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713926897; cv=none; b=r5PK4pyhTFPEt0Iq7IyMObWtPvbZNDmzHyuIWrZykGHWbm9VJ9IwL2HIhmt0VPZrfTHpWFOjkwzwm3Dm9L/PLYbH8tLTwJ9EJ3ZiE4f1RGXmVuj+a3QVAGFiAPhM6W+nW747mpw5niIzR7ue/85mQCRK6DhX+Vu9TboHAcisaf8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1713926897; c=relaxed/simple; bh=oBkaJ+c37KRZOYS0Ox9TtOjrL/EE+7lyjeMgEPOwb0k=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=QjlNBSq5z0dGAWsbq/JsZuc/KOqh7i6cG1RJzzQ/j4bxx66PbTwThOiKGS1rp5KDtuqDBvh+SrStGGP8E/0xxip12T1W0lPo0kyE1eS2/I81E7hLFFMwNay1//oiGyDnHnByhdtnSw47wRrXr1n46+lmJxG7HPwAAh/tpMCFE14= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=toshiba.co.jp; spf=pass smtp.mailfrom=toshiba.co.jp; arc=none smtp.client-ip=210.130.202.135 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=toshiba.co.jp Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=toshiba.co.jp Received: by mo-csw.securemx.jp (mx-mo-csw1801) id 43O2lgs33503872; Wed, 24 Apr 2024 11:47:42 +0900 X-Iguazu-Qid: 2yAbLYkr5BMomgzZgL X-Iguazu-QSIG: v=2; s=0; t=1713926861; q=2yAbLYkr5BMomgzZgL; m=3GSGlEv+dwGzf9o0K+OlFkOxsgoD11tzV5SklFxQtOs= Received: from imx12-a.toshiba.co.jp ([38.106.60.135]) by relay.securemx.jp (mx-mr1802) id 43O2ldI82096958 (version=TLSv1.3 cipher=TLS_AES_256_GCM_SHA384 bits=256 verify=NOT); Wed, 24 Apr 2024 11:47:40 +0900 X-SA-MID: 20405598 From: Yuji Ishikawa To: Hans Verkuil , Laurent Pinchart , Mauro Carvalho Chehab , Rob Herring , Krzysztof Kozlowski , Conor Dooley , "Rafael J . Wysocki" , Nobuhiro Iwamatsu , Yuji Ishikawa Cc: linux-media@vger.kernel.org, devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org Subject: [PATCH v10 5/6] documentation: media: add documentation for Toshiba Visconti Video Input Interface driver Date: Wed, 24 Apr 2024 11:42:14 +0900 X-TSB-HOP2: ON Message-Id: <20240424024215.1624299-6-yuji2.ishikawa@toshiba.co.jp> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240424024215.1624299-1-yuji2.ishikawa@toshiba.co.jp> References: <20240424024215.1624299-1-yuji2.ishikawa@toshiba.co.jp> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Added description of Video Input Interface driver of Toshiba Visconti architecture. It includes hardware organization, structure of the driver and metadata format for embedded image signal processor. Signed-off-by: Yuji Ishikawa --- Changelog v3: - Newly add documentation to describe SW and HW Changelog v4: - no change Changelog v5: - no change Changelog v6: - add description of CSI2RX subdevice - add ordering of ioctl(S_FMT) and ioctl(S_EXT_CTRLS) Changelog v7: - no change Changelog v8: - add usage of V4L2_CTRL_TYPE_VISCONTI_ISP Changelog v9: - fix warning: set reference target for keyword V4L2_CTRL_TYPE_VISCONTI_ISP Changelog v10: - use parameter buffers instead of compound control - removed description of vendor specific compound control - add description of parameter buffers for ISP control - update directory structure - remove documents under driver-api - add documents to admin-guide, userspace-api .../admin-guide/media/v4l-drivers.rst | 1 + .../admin-guide/media/visconti-viif.dot | 18 ++ .../admin-guide/media/visconti-viif.rst | 252 ++++++++++++++++++ .../userspace-api/media/v4l/meta-formats.rst | 1 + .../media/v4l/metafmt-visconti-viif.rst | 48 ++++ 5 files changed, 320 insertions(+) create mode 100644 Documentation/admin-guide/media/visconti-viif.dot create mode 100644 Documentation/admin-guide/media/visconti-viif.rst create mode 100644 Documentation/userspace-api/media/v4l/metafmt-visconti-viif.rst diff --git a/Documentation/admin-guide/media/v4l-drivers.rst b/Documentation/admin-guide/media/v4l-drivers.rst index f4bb2605f0..acf62dcd65 100644 --- a/Documentation/admin-guide/media/v4l-drivers.rst +++ b/Documentation/admin-guide/media/v4l-drivers.rst @@ -30,5 +30,6 @@ Video4Linux (V4L) driver-specific documentation si476x starfive_camss vimc + visconti-viif visl vivid diff --git a/Documentation/admin-guide/media/visconti-viif.dot b/Documentation/admin-guide/media/visconti-viif.dot new file mode 100644 index 0000000000..239d9fa2b3 --- /dev/null +++ b/Documentation/admin-guide/media/visconti-viif.dot @@ -0,0 +1,18 @@ +digraph board { + rankdir=TB + n00000001 [label="{{ 0} | visconti-viif:csi2rx\n/dev/v4l-subdev0 | { 1}}", shape=Mrecord, style=filled, fillcolor=green] + n00000001:port1 -> n00000004:port0 + n00000004 [label="{{ 0 | 4} | visconti-viif:isp\n/dev/v4l-subdev1 | { 1 | 2 | 3 | 5}}", shape=Mrecord, style=filled, fillcolor=green] + n00000004:port1 -> n0000000b + n00000004:port2 -> n0000000f + n00000004:port3 -> n00000013 + n00000004:port5 -> n0000001b + n0000000b [label="viif_capture_post0\n/dev/video0", shape=box, style=filled, fillcolor=yellow] + n0000000f [label="viif_capture_post1\n/dev/video1", shape=box, style=filled, fillcolor=yellow] + n00000013 [label="viif_capture_sub\n/dev/video2", shape=box, style=filled, fillcolor=yellow] + n00000017 [label="viif_params\n/dev/video3", shape=box, style=filled, fillcolor=yellow] + n00000017 -> n00000004:port4 + n0000001b [label="viif_stats\n/dev/video4", shape=box, style=filled, fillcolor=yellow] + n0000002b [label="{{} | imx219 1-0010\n/dev/v4l-subdev2 | { 0}}", shape=Mrecord, style=filled, fillcolor=green] + n0000002b:port0 -> n00000001:port0 +} diff --git a/Documentation/admin-guide/media/visconti-viif.rst b/Documentation/admin-guide/media/visconti-viif.rst new file mode 100644 index 0000000000..13d59cd379 --- /dev/null +++ b/Documentation/admin-guide/media/visconti-viif.rst @@ -0,0 +1,252 @@ +.. SPDX-License-Identifier: GPL-2.0 + +====================================================== +Visconti Video Input Interface Driver (visconti-viif) +====================================================== + +Introduction +============ + +This file documents the driver for the Video Input Interface (VIIF) that is +part of Toshiba Visconti SoCs. +The driver is located under drivers/media/platform/toshiba/visconti and uses +the Media-Controller API. + +The Visconti VIIF Hardware +========================== + +The Visconti VIIF hardware is a proprietary video capture device. +Following function modules are integrated: + +* MIPI CSI2 receiver (CSI2RX) +* L1 Image Signal Processor (L1ISP) + + * Correction, enhancement, adjustment on RAW pictures. + +* L2 Image Signal Processor (L2ISP) + + * Lens distortion correction + * Scaling + * Cropping + +* Video DMAC + + * format picture (RGB, YUV, Grayscale, ...) + * write picture into DRAM + +Visconti5 SoC has two VIIF hardware instances. + +Topology +======== + +.. _visconti_viif_topology_graph: + +.. kernel-figure:: visconti-viif.dot + :alt: Diagram of the default media pipeline topology + :align: center + +The driver has 5 video devices: + +- viif_capture_post0: capture device for image. + - corresponds to L2ISP and Video DMAC HW. +- viif_capture_post1: capture device for image. + - corresponds to L2ISP and Video DMAC HW. +- viif_capture_sub: capture device for RAW image. + - corresponds to Video DMAC HW. +- viif_params: a metadata output device that receives ISP parameters. + - corresponds to L1ISP and L2ISP HW. +- viif_stats: a metadata capture device that sends statistics. + - corresponds to L1ISP and L2ISP HW. + +The driver has 2 subdevices: + +- visconti-viif:csi2rx: CSI2 receiver operation. + - corresponds to CSI2RX HW. +- visconti-viif:isp: Image Signal Processor operation. + - corresponds to L1ISP and L2ISP HW. + +viif_capture_post0, viif_capture_post1 - Processed Image Capture Video Node +--------------------------------------------------------------------------- + +These video nodes are used for capturing images processed at ISPs. +They capture only following formats: + +- RGB3 +- AR24 +- YM16 +- YM24 +- Y16 + +Bayer format is not supported. Use viif_capture_sub instead. + +POST0 and POST1 can output images from the same input image +using different cropping and scaling settings. + +viif_capture_sub - Raw Image Capture Video Node +----------------------------------------------- + +This video node is used for capturing bayer image from the sensor. +The output picture has exactly the same resolution and format as the sensor input. +The following depth of bayer format is supported: + +- 8bit +- 10bit +- 12bit +- 14bit + +visconti-viif:csi2rx - CSI2 Receiver Subdevice Node +--------------------------------------------------- + +This subdevice node corresponds to a MIPI CSI2 receiver. +It resides between an image sensor subdevice and the ISP subdevice. +It controls CSI2 link configuration and training process. + +visconti-viif:isp - ISP Subdevice Node +-------------------------------------- + +This subdevice node corresponds to L1/L2 ISPs. +It receives pictures from an sensor (via CSI2RX), +applies multiple operations on pictures, then passes resulting images to capture nodes. + +L1 ISP provides following operations: + +- Input: accepts 8, 10, 12, 14bit bayer format +- Preprocessing: generate intermediate data (24bit RAW) + - HDRE: HDR expansion (only for PWL image); + see :c:type:`viif_l1_hdre_config`, :c:type:`viif_l1_input_mode_config` + - SLIC: Image Extraction (x3 12bit planes for preprocessing); + see :c:type:`viif_l1_img_extraction_config` + - ABPC/DPC: Defect pixel correction :c:type:`viif_l1_dpc_config` + - PWHB: Preset white balance; see :c:type:`viif_l1_preset_white_balance_config` + - RCNR: RAW color noise reduction; see :c:type:`viif_l1_raw_color_noise_reduction_config` + - HDRS: HDR synthesis; see :c:type:`viif_l1_hdrs_config` +- Processing on RAW image + - BLVC: black level correction and normalization; + see :c:type:`viif_l1_black_level_correction_config` + - LSSC: Lens shading correction; see :c:type:`viif_l1_lsc_config` + - MPRO: digital amplifier; see :c:type:`viif_l1_main_process_config` + - MPRO: bayer demosaicing; see :c:type:`viif_l1_main_process_config` + - MPRO: color matrix correction; see :c:type:`viif_l1_main_process_config` + - HDRC: HDR compression; + see :c:type:`viif_l1_hdrc_config`, :c:type:`viif_l1_hdrc_ltm_config`, + :c:type:`viif_l1_rgb_to_y_coef_config` +- Processing on RGB/YUV image + - VPRO: gamma correction; see :c:type:`viif_l1_gamma_config` + - VPRO: RGB2YUV; + see :c:type:`viif_l1_rgb_to_y_coef_config`, + :c:type:`viif_l1_img_quality_adjustment_config` + - VPRO: image quality adjustment; see :c:type:`viif_l1_img_quality_adjustment_config` +- Output: 16bit YUV +- Feedback loop with software + - AWHB: auto white balance; see :c:type:`viif_l1_awb_config`, + :c:type:`viif_isp_capture_status` + - AEXP: auto exposure (average luminance calculation); + see :c:type:`viif_l1_avg_lum_generation_config`, + :c:type:`viif_l1_rgb_to_y_coef_config`, :c:type:`viif_isp_capture_status` + - AG: analog gain calculation; + see :c:type:`viif_l1_ag_mode_config`, :c:type:`viif_l1_ag_config` + +L2 ISP provides following operations: + +- Input: accepts 16bit YUV +- Operations: + - Lens undistortion; see :c:type:`viif_l2_undist` + - Scaling; see :c:type:`viif_l2_roi` + - Cropping; see :c:type:`viif_l2_roi` + - Gamma correction; see :c:type:`viif_l2_gamma_config` + - YUV2RGB +- Output: RGB, YUV422, YUV444 + +ISP configurations/parameters are passed from userland via viif_params node. +The status of ISP operations are passed to userland via viif_stats node. + +.. _viif_params: + +viif_params - ISP Parameters Video Node +--------------------------------------- + +The viif_params video node receives a set of ISP parameters from userspace +to be applied to the hardware during a video stream. + +The buffer format is defined by struct :c:type:`visconti_viif_isp_config`, and userspace should set +:ref:`V4L2_META_FMT_VISCONTI_VIIF_PARAMS ` as the data format. + +.. _viif_stats: + +viif_stats - Statistics Video Node +---------------------------------- + +The viif_stats video node provides current status of ISP. + +Following information is included: + +* statistics of auto white balance +* average luminance information which can be used by auto exposure software impl. + +The buffer format is defined by struct :c:type:`visconti_viif_isp_stat`, and userspace should set +:ref:`V4L2_META_FMT_VISCONTI_VIIF_STATS ` as the data format. + +Capturing Video Frames Example +============================== + +In the following example, +imx219 camera is connected to pad 0 of 'visconti-viif:isp'. + +The following commands can be used to capture video from the main path 0 +with dimension 1024x1024 and RGB format. + +.. code-block:: bash + + # set the links + media-ctl -d platform:visconti-viif-0 -r + media-ctl -d platform:visconti-viif-0 -l '"imx219 1-0010":0 -> "visconti-viif:csi2rx":0 [1]' + media-ctl -d platform:visconti-viif-0 -l '"visconti-viif:csi2rx":1 -> "visconti-viif:isp":0 [1]' + media-ctl -d platform:visconti-viif-0 -l '"visconti-viif:isp":1 -> "viif_capture_post0":0 [1]' + media-ctl -d platform:visconti-viif-0 -l '"visconti-viif:isp":2 -> "viif_capture_post1":0 [1]' + media-ctl -d platform:visconti-viif-0 -l '"visconti-viif:isp":3 -> "viif_capture_sub":0 [1]' + media-ctl -d platform:visconti-viif-0 -l '"viif_params":0 -> "visconti-viif:isp":4 [1]' + media-ctl -d platform:visconti-viif-0 -l '"visconti-viif:isp":5 -> "viif_stats":0 [1]' + + # set format for imx219 + media-ctl -d platform:visconti-viif-0 --set-v4l2 '"imx219 1-0010":0 [fmt:SRGGB10_1X10/1920x1080]' + + # set format for csi2rx + media-ctl -d platform:visconti-viif-0 --set-v4l2 '"visconti-viif:csi2rx":1 [fmt:SRGGB10_1X10/1920x1080]' + + # set format for isp pads ( + media-ctl -d platform:visconti-viif-0 --set-v4l2 '"visconti-viif:isp":1 [fmt:YUV8_1X24/1024 crop:(640,0)/1024x1024]' + + # set format for main path0 + v4l2-ctl -z platform:visconti-viif-0 -d viif_capture_post0 -v "width=1024,height=1024" + v4l2-ctl -z platform:visconti-viif-0 -d viif_capture_post0 -v "pixelformat=RGB3" + + # start streaming + v4l2-ctl -z platform:visconti-viif-0 -d viif_capture_post0 --stream-mmap --stream-count 10 + + +Use of coherent memory +====================== + +Visconti5 SoC has two independent DDR SDRAM controllers. +Each controller is mapped to 36bit address space. + +Accelerator bus masters have two paths to access memory; +one is directly connected to SDRAM controller, +the another is connected via a cache coherency bus +which keeps coherency among CPUs. + +From accelerators and CPUs, the address map is following: + +* 0x0_8000_0000 DDR0 direct access +* 0x4_8000_0000 DDR0 coherency bus +* 0x8_8000_0000 DDR1 direct access +* 0xC_8000_0000 DDR1 coherency bus + +The base address can be specified with "memory" and "reserved-memory" elements +in a device tree description. +It's not recommended to mix direct address and coherent address. + +The Visconti5 VIIF driver always use only direct address to configure Video DMACs of the hardware. +This design is to avoid great performance loss at coherency bus caused by massive memory access. +You should not put the dma_coherent attribute to viif element in device tree. +Cache operations are done automatically by videobuf2 driver. diff --git a/Documentation/userspace-api/media/v4l/meta-formats.rst b/Documentation/userspace-api/media/v4l/meta-formats.rst index 0bb61fc5bc..b7def3d2c6 100644 --- a/Documentation/userspace-api/media/v4l/meta-formats.rst +++ b/Documentation/userspace-api/media/v4l/meta-formats.rst @@ -18,4 +18,5 @@ These formats are used for the :ref:`metadata` interface only. metafmt-uvc metafmt-vsp1-hgo metafmt-vsp1-hgt + metafmt-visconti-viif metafmt-vivid diff --git a/Documentation/userspace-api/media/v4l/metafmt-visconti-viif.rst b/Documentation/userspace-api/media/v4l/metafmt-visconti-viif.rst new file mode 100644 index 0000000000..dc4b31627f --- /dev/null +++ b/Documentation/userspace-api/media/v4l/metafmt-visconti-viif.rst @@ -0,0 +1,48 @@ +.. SPDX-License-Identifier: GPL-2.0 + +.. _v4l2-meta-fmt-visconti-viif-params: + +.. _v4l2-meta-fmt-visconti-viif-stats: + +*************************************************************************************** +V4L2_META_FMT_VISCONTI_VIIF_PARAMS ('vifp'), V4L2_META_FMT_VISCONTI_VIIF_STATS ('vifs') +*************************************************************************************** + +Configuration parameters +======================== + +The configuration parameters are passed to the +:ref:`viif_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:`visconti_viif_isp_config` defined in +``visconti_viif.h``. So the structure can be obtained from the buffer by: + +.. code-block:: c + + struct visconti_viif_isp_config *params = (struct visconti_viif_isp_config*) buffer; + +VIIF statistics +=============== + +The VIIF device collects different statistics over an input Bayer frame. +Those statistics are obtained from the :ref:`viif_stats ` +metadata capture video node, +using the :c:type:`v4l2_meta_format` interface. The buffer contains a single +instance of the C structure :c:type:`visconti_viif_isp_stat` defined in +``visconti_viif.h``. So the structure can be obtained from the buffer by: + +.. code-block:: c + + struct visconti_viif_isp_stat *stats = (struct visconti_viif_isp_stat*) buffer; + +The statistics collected are Exposure, AWB (auto white balance) and errors. +See :c:type:`visconti_viif_isp_stat` for details of the statistics. + +The statistics and configuration parameters described here are usually +consumed and produced by dedicated user space libraries that comprise the +tuning tools using software control loop. + +visconti viif uAPI data types +============================= + +.. kernel-doc:: include/uapi/linux/visconti_viif.h -- 2.25.1