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{ "id": 11253, "url": "https://patchwork.libcamera.org/api/1.1/covers/11253/?format=api", "web_url": "https://patchwork.libcamera.org/cover/11253/", "project": { "id": 1, "url": "https://patchwork.libcamera.org/api/1.1/projects/1/?format=api", "name": "libcamera", "link_name": "libcamera", "list_id": "libcamera_core", "list_email": "libcamera-devel@lists.libcamera.org", "web_url": "", "scm_url": "", "webscm_url": "" }, "msgid": "<20210212113312.239076-1-naush@raspberrypi.com>", "date": "2021-02-12T11:33:07", "name": "[libcamera-devel,0/5] DelayedControls updates and fixes", "submitter": { "id": 34, "url": "https://patchwork.libcamera.org/api/1.1/people/34/?format=api", "name": "Naushir Patuck", "email": "naush@raspberrypi.com" }, "mbox": "https://patchwork.libcamera.org/cover/11253/mbox/", "series": [ { "id": 1683, "url": "https://patchwork.libcamera.org/api/1.1/series/1683/?format=api", "web_url": "https://patchwork.libcamera.org/project/libcamera/list/?series=1683", "date": "2021-02-12T11:33:07", "name": "DelayedControls updates and fixes", "version": 1, "mbox": "https://patchwork.libcamera.org/series/1683/mbox/" } ], "comments": "https://patchwork.libcamera.org/api/covers/11253/comments/", "headers": { "Return-Path": "<libcamera-devel-bounces@lists.libcamera.org>", "X-Original-To": "parsemail@patchwork.libcamera.org", "Delivered-To": "parsemail@patchwork.libcamera.org", "Received": [ "from lancelot.ideasonboard.com (lancelot.ideasonboard.com\n\t[92.243.16.209])\n\tby patchwork.libcamera.org (Postfix) with ESMTPS id 2DFACBD160\n\tfor <parsemail@patchwork.libcamera.org>;\n\tFri, 12 Feb 2021 11:37:34 +0000 (UTC)", "from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 667DC63776;\n\tFri, 12 Feb 2021 12:37:33 +0100 (CET)", "from mail-wm1-x32c.google.com (mail-wm1-x32c.google.com\n\t[IPv6:2a00:1450:4864:20::32c])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id D560B6376F\n\tfor <libcamera-devel@lists.libcamera.org>;\n\tFri, 12 Feb 2021 12:37:31 +0100 (CET)", "by mail-wm1-x32c.google.com with SMTP id y134so653508wmd.3\n\tfor <libcamera-devel@lists.libcamera.org>;\n\tFri, 12 Feb 2021 03:37:31 -0800 (PST)", "from naush-laptop.patuck.local ([88.97.76.4])\n\tby smtp.gmail.com with ESMTPSA id\n\tv5sm10005020wro.71.2021.02.12.03.37.30\n\t(version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256);\n\tFri, 12 Feb 2021 03:37:30 -0800 (PST)" ], "Authentication-Results": "lancelot.ideasonboard.com;\n\tdkim=fail reason=\"signature verification failed\" (2048-bit key;\n\tunprotected) header.d=raspberrypi.com header.i=@raspberrypi.com\n\theader.b=\"lq+06Qyg\"; dkim-atps=neutral", "DKIM-Signature": "v=1; a=rsa-sha256; c=relaxed/relaxed;\n\td=raspberrypi.com; s=google;\n\th=from:to:cc:subject:date:message-id:mime-version\n\t:content-transfer-encoding;\n\tbh=0qhb53j9t0gM4sA8vnT7g+jOOUA5U3dRZj1Rfci4bIU=;\n\tb=lq+06Qyg1aOKCHuICq494ZpzkX7oW7r0ti2WWiOtZwBZwy1uOAUcEHoQHcHVdb2fHE\n\tQkycBeviYUXLdxqygP2EgoMvT7NA9HBJWBwj/G9eso0zLWOUj07+jT5yOKhoi1EvByh5\n\tqatXDD9AI2eVpZ5R03qqCuU992P2baVowZPcURjzuyknLYnx94b6znC/mgnRtFI9JplT\n\tqaZls/bwSFYaWzwEGXfMWsEzv34IhqH87HGMVtjSoQL4UwFGBSCLlXex4WkRNuFN1KFH\n\t9v8RFexvjBkWhwYbtNBYMohEMaEzzuvU/DugWpmPmJdvJtHC1hm1Kl+d6aFUvfOnu62n\n\tm1zg==", "X-Google-DKIM-Signature": "v=1; a=rsa-sha256; c=relaxed/relaxed;\n\td=1e100.net; s=20161025;\n\th=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version\n\t:content-transfer-encoding;\n\tbh=0qhb53j9t0gM4sA8vnT7g+jOOUA5U3dRZj1Rfci4bIU=;\n\tb=RbYL3VCWkx7wd+C9E+GQk9TsEBq+v7bsBs6i1fzHPE5DvBSfCcSENK78kwUT4EnW7Q\n\tlygDnL+vbqoTJzTEhBW6cj47OauMoxew6Uygu3HlLUhlk9WjurFdO09pPAVe53vEpe/4\n\t+xa9vY6ndg7bvLFazkULL8IsY5/xqKGSR3rVjKClKjmFtXz6N45yO+G8psbX5eQk2CzP\n\tkD/Kc/S2UkcxxjcrCdlTw47SvKGG2smAT+7NQJjrg4rNTtwEqZgDQkTQjXDMYFz93nK0\n\tTS2QyQtn2BFMT7jYQ3SKVYxZG0m/cgYqScSWP/6Goru4/odzavRhmjejNU5NSR/kCwrg\n\tzUPw==", "X-Gm-Message-State": "AOAM531QL+DBVzWUQ9HkuQ48poOwgPdD/HAHAQ+jNH2g93+E0Q/JyobJ\n\t3WCu38GuW4mt7pq5rw8aBesVVgcsTHUOgQuU", "X-Google-Smtp-Source": "ABdhPJxI27fHa5EICCUrQ+9MD105RojGYQhj+vh+jMiCZJfqjjy6HSzC9RP2NqN0jW2WcMB53LYqOA==", "X-Received": "by 2002:a1c:29c4:: with SMTP id p187mr2130004wmp.8.1613129851065;\n\tFri, 12 Feb 2021 03:37:31 -0800 (PST)", "From": "Naushir Patuck <naush@raspberrypi.com>", "To": "libcamera-devel@lists.libcamera.org", "Date": "Fri, 12 Feb 2021 11:33:07 +0000", "Message-Id": "<20210212113312.239076-1-naush@raspberrypi.com>", "X-Mailer": "git-send-email 2.25.1", "MIME-Version": "1.0", "Subject": "[libcamera-devel] [PATCH 0/5] DelayedControls updates and fixes", "X-BeenThere": "libcamera-devel@lists.libcamera.org", "X-Mailman-Version": "2.1.29", "Precedence": "list", "List-Id": "<libcamera-devel.lists.libcamera.org>", "List-Unsubscribe": "<https://lists.libcamera.org/options/libcamera-devel>,\n\t<mailto:libcamera-devel-request@lists.libcamera.org?subject=unsubscribe>", "List-Archive": "<https://lists.libcamera.org/pipermail/libcamera-devel/>", "List-Post": "<mailto:libcamera-devel@lists.libcamera.org>", "List-Help": "<mailto:libcamera-devel-request@lists.libcamera.org?subject=help>", "List-Subscribe": "<https://lists.libcamera.org/listinfo/libcamera-devel>,\n\t<mailto:libcamera-devel-request@lists.libcamera.org?subject=subscribe>", "Content-Type": "text/plain; charset=\"us-ascii\"", "Content-Transfer-Encoding": "7bit", "Errors-To": "libcamera-devel-bounces@lists.libcamera.org", "Sender": "\"libcamera-devel\" <libcamera-devel-bounces@lists.libcamera.org>" }, "content": "Hi all,\n\nThis patchset mainly addresses some minor issues we have encountered with DelayedControls\nwhen running on the Raspberry Pi platform. Apologies for the slightly long cover letter,\nbut I wanted to explain the problems we are seeing in a bit of detail :-)\n\nPatch 1/5\nThis adds the notion of priority write to fixup the known issue of settings VBLANK and\nEXPOSURE in a single batch. It is simply a port of the fix applied to StaggeredCtrl\nthat had been reviewed and subsequently deprecated, so hopefully nothing too controversial.\n\nPatch 2/5\nThis is simply a python script that I am using to debug the small problems (more details\nbelow) that we have encountered. It parses the DelayedControls logs and nicely tabulates\nthe results to show what controls and values have been set/queued/get on each frame.\nThis has helped me tremendously in identifying problems and fixing them. However, this\nmay not be useful to others, so I am happy to not have this merged if folks do not think\nit is the right place to put it.\n\nPatch 3/5\nFixes a spurious write to the device on startup. The following is an extract from using\nthe script to parse the logs:\n\nFrame Action Gain Exposure Vblank\n0 Write 0 [0] 52 [0] 531 [0] <<<<<\n0 Get 0 [0] 52 [0] 531 [0]\n0 Queue --- [-] --- [-] --- [-]\n1 Write 0 [0] --- [-] --- [-]\n1 Get 0 [0] 52 [0] 531 [0]\n1 Queue --- [-] --- [-] --- [-]\n2 Write --- [-] --- [-] --- [-]\n2 Get 0 [1] 52 [1] 531 [1]\n2 Queue 192 [4] 1664 [4] 531 [4]\n\nYou can see above, on frame 0 we are writing controls to the sensor, but this is unneeded.\nThis spurious write should really not happen as there is no controls queued by the\npipeline_handler at this point. It is, however, mostly inconsequential at runtime.\n\nPatch 4/5\nThis fixes an issue where controls queued by the pipeline handler are delayed by and\nadditional frame when writing. You can see better in the parsed log:\n\nFrame Action Gain Exposure Vblank\n2 Write --- [-] --- [-] --- [-]\n2 Get 0 [1] 52 [1] 531 [1]\n2 Queue 192 [4] 1664 [4] 531 [4] <<<<<\n3 Write --- [-] --- [-] --- [-] <<<<<\n3 Get 0 [2] 52 [2] 531 [2]\n3 Queue 192 [5] 1664 [5] 531 [5]\n4 Write --- [-] 1664 [4] 531 [4] <<<<<\n4 Get 0 [3] 52 [3] 531 [3]\n4 Queue 192 [6] 1664 [6] 531 [6]\n\nOn frame 2, we queue controls from the pipeline handler. Exposure and Vblank must be\nwritten one frame before gain, so you would expect them to be written on frame 3 as\nnothing else is in the queue. However, they only get written on frame 4, one frame\nlater than expected.\n\nThis is because of how DelayedControls handles \"no-op\" queue items, i.e. frames where\nwe do not provide the helper with controls to use. It was adding one more no-op than\nneeded, and causing an extra frame delay when setting the control on the device.\n\nPatch 5/5\nWe had an off-by-one error when reading back values from the queues. See the parsed\nlogs below:\n\nFrame Action Gain Exposure Vblank\n7 Write 192 [6] 1664 [7] 531 [7] <<<<<\n7 Get 192 [6] 1664 [6] 531 [6]\n7 Queue 210 [9] 3174 [9] 1946 [9]\n8 Write 192 [7] 3526 [8] 2298 [8]\n8 Get 192 [7] 1664 [7] 531 [7] <<<<<\n8 Queue 210 [10] 3174 [10] 1946 [10]\n9 Write 213 [8] 3174 [9] 1946 [9]\n9 Get 213 [8] 3526 [8] 2298 [8] <<<<<\n9 Queue 213 [12] 3526 [12] 2298 [12]\n\nOn frame 7, we write exposure and vblank with values 1664 and 531 respectively. These\nvalues take 2 frames to consume, so should be retuned to the pipeline handler by the\nDelayedControls::get() on frame 9. However, it returns on frame 8 instead.\n\nThis only causes slight (but visible) oscillations in brightness in the AGC loop as\nthe values used by the sensor are not in lock-step to what is reported by DelayedControls::get().\n\nHope that is all reasonably well explained :-) Any questions, please do shout.\n\nRegards,\nNaush\n\nNaushir Patuck (5):\n libcamera: delayed_controls: Add notion of priority write\n utils: raspberrypi: Add a DelayedControls log parser\n libcamera: delayed_controls: Remove unneeded write when starting up\n libcamera: delayed_controls: Remove spurious no-op queued controls\n libcamera: delayed_controls: Fix off-by-one error in get()\n\n include/libcamera/internal/delayed_controls.h | 13 ++-\n src/libcamera/delayed_controls.cpp | 72 ++++++++++------\n src/libcamera/pipeline/ipu3/ipu3.cpp | 8 +-\n .../pipeline/raspberrypi/raspberrypi.cpp | 13 ++-\n src/libcamera/pipeline/rkisp1/rkisp1.cpp | 8 +-\n test/delayed_contols.cpp | 20 ++---\n utils/raspberrypi/delayedctrls_parse.py | 82 +++++++++++++++++++\n 7 files changed, 162 insertions(+), 54 deletions(-)\n create mode 100644 utils/raspberrypi/delayedctrls_parse.py" }