From patchwork Fri Aug 29 11:53:58 2025 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jacopo Mondi X-Patchwork-Id: 24265 Return-Path: X-Original-To: parsemail@patchwork.libcamera.org Delivered-To: parsemail@patchwork.libcamera.org Received: from lancelot.ideasonboard.com (lancelot.ideasonboard.com [92.243.16.209]) by patchwork.libcamera.org (Postfix) with ESMTPS id 52D92BD87C for ; Fri, 29 Aug 2025 11:54:30 +0000 (UTC) Received: from lancelot.ideasonboard.com (localhost [IPv6:::1]) by lancelot.ideasonboard.com (Postfix) with ESMTP id D0F9069328; Fri, 29 Aug 2025 13:54:28 +0200 (CEST) Authentication-Results: lancelot.ideasonboard.com; dkim=pass (1024-bit key; unprotected) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="mB2bij+U"; dkim-atps=neutral Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) by lancelot.ideasonboard.com (Postfix) with ESMTPS id CD2FF692F1 for ; Fri, 29 Aug 2025 13:54:23 +0200 (CEST) Received: from [192.168.1.102] (93-61-96-190.ip145.fastwebnet.it [93.61.96.190]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 8C2CF4AF1; Fri, 29 Aug 2025 13:53:18 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1756468398; bh=Xxs4zUCLpQHSbiJMe2xa6Brcir/RrSeEpTPGcLkb9pI=; h=From:Date:Subject:References:In-Reply-To:To:Cc:From; b=mB2bij+U8B5xkFg26qopvwzssWiOJG1xu9KqQHaG1QFMYRDJLpoYT6CgHz05XS6ak Ge8RWutX7RTWS5kk8m2Caiy8edOtcyErGAf0BYq1KPAxreFrfe0gXNVT4b/kTAfZRy Mr6c7CGiTWML7seLv+GvQcDaz/mC0CwAbblJYSEc= From: Jacopo Mondi Date: Fri, 29 Aug 2025 13:53:58 +0200 Subject: [PATCH 1/4] include: linux: Add v4l2-extensible-params.h MIME-Version: 1.0 Message-Id: <20250829-v4l2-params-v1-1-340773fb69ff@ideasonboard.com> References: <20250829-v4l2-params-v1-0-340773fb69ff@ideasonboard.com> In-Reply-To: <20250829-v4l2-params-v1-0-340773fb69ff@ideasonboard.com> To: libcamera-devel@lists.libcamera.org Cc: Jacopo Mondi X-Mailer: b4 0.14.2 X-Developer-Signature: v=1; a=openpgp-sha256; l=7499; i=jacopo.mondi@ideasonboard.com; h=from:subject:message-id; bh=Xxs4zUCLpQHSbiJMe2xa6Brcir/RrSeEpTPGcLkb9pI=; b=owEBbQKS/ZANAwAKAXI0Bo8WoVY8AcsmYgBosZTuEc0x9eLC6nyHQnCCB4q33G+uXkn1AFJCz g3N1xkd/yCJAjMEAAEKAB0WIQS1xD1IgJogio9YOMByNAaPFqFWPAUCaLGU7gAKCRByNAaPFqFW PEchD/4tKaz17qlzXPboJuCwW9n3996o8a+GJ/DeuoTPYmOagmE8Ee/wVaVnTIOIn1IeKXhEOJ7 Cz16sAwI94svHcmepTB/zV9JsOabOiORFaakJ7mPbqZxCV8bp2FX+gSc8TRx0M8ctBJQH95oSGt T+7505rrrBtqdEtT3lBMPDchRsd0H8wsP+b151BC3axFVQh2gsf8j3bZ2VTn3RL2zQeOvY/ecS9 eDaLDhBKFQCqt4ZD2/5vVUON3wXoI5GnjVX7yQIINeUG6dSrtjbFqt0mn+W0tWwR4ZeyAuin4PL anhzQb/ffMR1dGWe/BNVTVYVZTuqnNdZFKEVzzEzob8B+8StEfM5/R2pa2PgSygvqpVWnB5cpv1 kvy4rR5S1atR8riRV7EQF0j0A4pMC6+k36JTma9wm9CB2xYIQDMkyWJJv5oZgTsRzAOHxF9F7tb WeO7b107J+l1RiDmLmD9vt83oEybTCtb0OJ0QS7lI5sjliOa4GNz5pAZjcZ2RGQNm6TUIFvOq3Z S98e6CyIUkR6XxSIALNZ9sjy0dOFuKPHa7zgjWnT2RsVywUErYOasD0c8CqIwNyNtjHsJOCY0Uf JzUdRUVken8jqU4eLyH8yCLRAp/d5n6K1cxFohSLCJJUFVG1MqTpPwnD+itUqpHQZbu4fj26y42 LqJrOELN9B2hpyg== X-Developer-Key: i=jacopo.mondi@ideasonboard.com; a=openpgp; fpr=72392EDC88144A65C701EA9BA5826A2587AD026B X-BeenThere: libcamera-devel@lists.libcamera.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: libcamera-devel-bounces@lists.libcamera.org Sender: "libcamera-devel" Import the v4l2-extensible-params.h header from the Linux kernel sources. The file has not been merged in mainline Linux yet but is available at: https://lore.kernel.org/all/20250820-extensible-parameters-validation-v4-0-30fe5a99cb1f@ideasonboard.com/ Create the include/linux/media/ directory so that header files exported from the kernel which include this file do not need to be adjusted when imported in libcamera. Signed-off-by: Jacopo Mondi --- include/linux/media/v4l2-extensible-params.h | 144 +++++++++++++++++++++++++++ 1 file changed, 144 insertions(+) diff --git a/include/linux/media/v4l2-extensible-params.h b/include/linux/media/v4l2-extensible-params.h new file mode 100644 index 0000000000000000000000000000000000000000..2b93b5b4c04b3d29ddb7d509b4cbde64238d8c20 --- /dev/null +++ b/include/linux/media/v4l2-extensible-params.h @@ -0,0 +1,144 @@ +/* SPDX-License-Identifier: ((GPL-2.0+ WITH Linux-syscall-note) OR MIT) */ +/* + * Video4Linux2 extensible configuration parameters base types + * + * Copyright (C) 2025 Ideas On Board Oy + * Author: Jacopo Mondi + */ + +#ifndef _V4L2_PARAMS_H_ +#define _V4L2_PARAMS_H_ + +#include + +#define V4L2_PARAMS_FL_BLOCK_DISABLE (1U << 0) +#define V4L2_PARAMS_FL_BLOCK_ENABLE (1U << 1) + +/* + * Reserve the first 8 bits for V4L2_PARAMS_FL_* flag. Platform-specific flags + * should be defined as: + * #define PLATFORM_SPECIFIC_FLAG0 ((1U << V4L2_PARAMS_FL_PLATFORM_FLAGS(0)) + * #define PLATFORM_SPECIFIC_FLAG1 ((1U << V4L2_PARAMS_FL_PLATFORM_FLAGS(1)) + */ +#define V4L2_PARAMS_FL_PLATFORM_FLAGS(n) ((n) << 8) + +/** + * struct v4l2_params_block_header - V4L2 extensible parameters block header + * + * This structure represents the common part of all the ISP configuration + * blocks. Each parameters block shall embed an instance of this structure type + * as its first member, followed by the block-specific configuration data. The + * driver inspects this common header to discern the block type and its size and + * properly handle the block content by casting it to the correct block-specific + * type. + * + * The @type field is one of the values enumerated by each platform-specific ISP + * block types which specifies how the data should be interpreted by the driver. + * The @size field specifies the size of the parameters block and is used by the + * driver for validation purposes. + * + * The @flags field is a bitmask of per-block flags V4L2_PARAMS_FL_* and + * platform-specific flags specified by the platform-specific header. + * + * Documentation of the platform-specific flags handling is specified by the + * platform-specific block header type: + * + * - Rockchip RkISP1: :c:type:`rkisp1_ext_params_block_type` + * - Amlogic C3: :c:type:`c3_isp_params_block_type` + * + * Userspace is responsible for correctly populating the parameters block header + * fields (@type, @flags and @size) and the block-specific parameters. + * + * @type: The parameters block type (platform-specific) + * @flags: A bitmask of block flags (platform-specific) + * @size: Size (in bytes) of the parameters block, including this header + */ +struct v4l2_params_block_header { + __u16 type; + __u16 flags; + __u32 size; +} __attribute__((aligned(8))); + +/** + * v4l2_params_buffer_size - Calculate size of v4l2_params_buffer for a platform + * + * Users of the v4l2 extensible parameters will have differing sized data arrays + * depending on their specific parameter buffers. Drivers and userspace will + * need to be able to calculate the appropriate size of the struct to + * accommodate all ISP configuration blocks provided by the platform. + * This macro provides a convenient tool for the calculation. + * + * Each driver shall provide a definition of their extensible parameters + * implementation data buffer size. As an example: + * + * #define PLATFORM_BLOCKS_MAX_SIZE \ + * sizeof(platform_block_0) + \ + * sizeof(platform_block_1) + * + * #define PLATFORM_BUFFER_SIZE \ + * v4l2_params_buffer_size(PLATFORM_BLOCKS_MAX_SIZE) + * + * Drivers are then responsible for allocating buffers of the proper size + * by assigning PLATFORM_BUFFER_SIZE to the per-plane size of the videobuf2 + * .queue_setup() operation and userspace shall use PLATFORM_BUFFER_SIZE + * when populating the ISP configuration data buffer. + * + * @max_params_size: The total size of the ISP configuration blocks + */ +#define v4l2_params_buffer_size(max_params_size) \ + (offsetof(struct v4l2_params_buffer, data) + (max_params_size)) + +/** + * struct v4l2_params_buffer - V4L2 extensible parameters configuration + * + * This struct contains the configuration parameters of the ISP algorithms, + * serialized by userspace into a data buffer. Each configuration parameter + * block is represented by a block-specific structure which contains a + * :c:type:`v4l2_params_block_header` entry as first member. Userspace populates + * the @data buffer with configuration parameters for the blocks that it intends + * to configure. As a consequence, the data buffer effective size changes + * according to the number of ISP blocks that userspace intends to configure and + * is set by userspace in the @data_size field. + * + * The parameters buffer is versioned by the @version field to allow modifying + * and extending its definition. Userspace shall populate the @version field to + * inform the driver about the version it intends to use. The driver will parse + * and handle the @data buffer according to the data layout specific to the + * indicated version and return an error if the desired version is not + * supported. + * + * For each ISP block that userspace wants to configure, a block-specific + * structure is appended to the @data buffer, one after the other without gaps + * in between nor overlaps. Userspace shall populate the @data_size field with + * the effective size, in bytes, of the @data buffer. + * + * Drivers shall take care of properly sizing of the extensible parameters + * buffer @data array. The v4l2_params_buffer type is defined with a + * flexible-array-member at the end, which resolves to a size of 0 bytes when + * inspected with sizeof(struct v4l2_params_buffer). This of course is not + * suitable for neither buffer allocation in the kernel driver nor for proper + * handling in userspace of the @data buffer it has to populate. + * + * Drivers using this type in their userspace API definition are responsible + * for providing the exact definition of the @data buffer size using the + * v4l2_params_buffer_size() macro. The size shall be used + * by the driver for buffers allocation and by userspace for populating the + * @data buffer before queueing it to the driver + * + * Drivers that were already using extensible-parameters before the introduction + * of this file define their own type-convertible implementation of this + * type, see: + * - Rockchip RkISP1: :c:type:`rkisp1_ext_params_cfg` + * - Amlogic C3: :c:type:`c3_isp_params_cfg` + * + * @version: The parameters buffer version (platform-specific) + * @data_size: The configuration data effective size, excluding this header + * @data: The configuration data + */ +struct v4l2_params_buffer { + __u32 version; + __u32 data_size; + __u8 data[]; +}; + +#endif /* _V4L2_PARAMS_H_ */