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{ "id": 11299, "url": "https://patchwork.libcamera.org/api/covers/11299/?format=api", "web_url": "https://patchwork.libcamera.org/cover/11299/", "project": { "id": 1, "url": "https://patchwork.libcamera.org/api/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": "<20210216085342.1012717-1-naush@raspberrypi.com>", "date": "2021-02-16T08:53:37", "name": "[libcamera-devel,v2,0/5] DelayedControls updates and fixes", "submitter": { "id": 34, "url": "https://patchwork.libcamera.org/api/people/34/?format=api", "name": "Naushir Patuck", "email": "naush@raspberrypi.com" }, "mbox": "https://patchwork.libcamera.org/cover/11299/mbox/", "series": [ { "id": 1694, "url": "https://patchwork.libcamera.org/api/series/1694/?format=api", "web_url": "https://patchwork.libcamera.org/project/libcamera/list/?series=1694", "date": "2021-02-16T08:53:37", "name": "DelayedControls updates and fixes", "version": 2, "mbox": "https://patchwork.libcamera.org/series/1694/mbox/" } ], "comments": "https://patchwork.libcamera.org/api/covers/11299/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 98ECBBD1EF\n\tfor <parsemail@patchwork.libcamera.org>;\n\tTue, 16 Feb 2021 08:53:49 +0000 (UTC)", "from lancelot.ideasonboard.com (localhost [IPv6:::1])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTP id 0056B637D2;\n\tTue, 16 Feb 2021 09:53:48 +0100 (CET)", "from mail-wm1-x334.google.com (mail-wm1-x334.google.com\n\t[IPv6:2a00:1450:4864:20::334])\n\tby lancelot.ideasonboard.com (Postfix) with ESMTPS id C65E963762\n\tfor <libcamera-devel@lists.libcamera.org>;\n\tTue, 16 Feb 2021 09:53:47 +0100 (CET)", "by mail-wm1-x334.google.com with SMTP id a207so485187wmd.1\n\tfor <libcamera-devel@lists.libcamera.org>;\n\tTue, 16 Feb 2021 00:53:47 -0800 (PST)", "from naush-laptop.patuck.local ([88.97.76.4])\n\tby smtp.gmail.com with ESMTPSA id\n\te1sm9300369wrd.44.2021.02.16.00.53.46\n\t(version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256);\n\tTue, 16 Feb 2021 00:53:46 -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=\"Hz7Ce4pk\"; 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\n\tTue, 16 Feb 2021 00:53:46 -0800 (PST)", "From": "Naushir Patuck <naush@raspberrypi.com>", "To": "libcamera-devel@lists.libcamera.org", "Date": "Tue, 16 Feb 2021 08:53:37 +0000", "Message-Id": "<20210216085342.1012717-1-naush@raspberrypi.com>", "X-Mailer": "git-send-email 2.25.1", "MIME-Version": "1.0", "Subject": "[libcamera-devel] [PATCH v2 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,\n\nHere is a revised version of the DelayedControls patch. The only difference between v2 and v1 is in patch 4/5 where the fix was incomplete. To reiterate, here is a summary of the patches:\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. This problem is mostly inconsequential.\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\nAs a consequence of this change, we must also ensure that controls that have been sent\nto the device must have the update flag cleared or there is a change it may be re-used\nwhen going around the ring buffer. \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\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 | 79 ++++++++++-----\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 | 98 +++++++++++++++++++\n 7 files changed, 183 insertions(+), 56 deletions(-)\n create mode 100644 utils/raspberrypi/delayedctrls_parse.py" }