From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from perceval.ideasonboard.com (perceval.ideasonboard.com [213.167.242.64]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9ED551C9B87; Thu, 24 Oct 2024 11:08:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.167.242.64 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729768136; cv=none; b=XsajUsis42W1G7Jci6/Ak3wlqXpquhgV9sUnPRGrd9irn1Oy3B8Rcng96UzXStZw/5WrMxilRgslKVOpmTi24hszcZDV08w3eVil7T7zywW88n0CZjvlSfvYqQ4sMsDA/J3VLJhJkCHHjyqxt4Ks9l+reERWp7W085L5mWz4JzI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729768136; c=relaxed/simple; bh=eXJrCgkDKcZTI6gMXzDZwu5wzmDIPGiDJmpLeVOLhmQ=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=bB0m/I1vzmRIKOXBiXRrlrTzY4QpaazKQzs6WK+1jLHnCeT14StZnyVCADFkuehPkfCYJmjIqYAM8VdzT8L7POUorpslQ/22whtd5LW6FqION61mAUQh3xqtGdBPtbcridIemDlmhOs5NBaDS0HYwa0f1vl0135FV2/u5PB1uJM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=ideasonboard.com; spf=pass smtp.mailfrom=ideasonboard.com; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b=XA5sTyX7; arc=none smtp.client-ip=213.167.242.64 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=ideasonboard.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=ideasonboard.com header.i=@ideasonboard.com header.b="XA5sTyX7" Received: from [192.168.88.20] (91-157-155-49.elisa-laajakaista.fi [91.157.155.49]) by perceval.ideasonboard.com (Postfix) with ESMTPSA id 43FA93D5; Thu, 24 Oct 2024 13:06:57 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=ideasonboard.com; s=mail; t=1729768018; bh=eXJrCgkDKcZTI6gMXzDZwu5wzmDIPGiDJmpLeVOLhmQ=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=XA5sTyX7XyLi5Gc4fBL/ZmgzC+0Ef0pK49CEE1KacdR3q6sSSot6smcJ7jIVE7b29 0Nq/nS/ZZxIQIegpng8jF71eUF8Nbq5F+I1lB1GJZOpHLbS6f1dLUev+fqk9n4LEw6 b+Xb6keo64nC9W7NkZerTKWyfzieo8u15pQpmsCs= Message-ID: Date: Thu, 24 Oct 2024 14:08:42 +0300 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v6 3/4] media: raspberrypi: Add support for RP1-CFE To: Hans Verkuil Cc: Mauro Carvalho Chehab , Raspberry Pi Kernel Maintenance , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Florian Fainelli , Broadcom internal kernel review list , Rob Herring , Krzysztof Kozlowski , linux-media@vger.kernel.org, linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org, Naushir Patuck , Laurent Pinchart , Sakari Ailus , Jacopo Mondi , Kieran Bingham References: <20241003-rp1-cfe-v6-0-d6762edd98a8@ideasonboard.com> <20241003-rp1-cfe-v6-3-d6762edd98a8@ideasonboard.com> <4d9e340e-2ae7-495b-8623-0d10398e1c3d@xs4all.nl> Content-Language: en-US From: Tomi Valkeinen Autocrypt: addr=tomi.valkeinen@ideasonboard.com; keydata= xsFNBE6ms0cBEACyizowecZqXfMZtnBniOieTuFdErHAUyxVgtmr0f5ZfIi9Z4l+uUN4Zdw2 wCEZjx3o0Z34diXBaMRJ3rAk9yB90UJAnLtb8A97Oq64DskLF81GCYB2P1i0qrG7UjpASgCA Ru0lVvxsWyIwSfoYoLrazbT1wkWRs8YBkkXQFfL7Mn3ZMoGPcpfwYH9O7bV1NslbmyJzRCMO eYV258gjCcwYlrkyIratlHCek4GrwV8Z9NQcjD5iLzrONjfafrWPwj6yn2RlL0mQEwt1lOvn LnI7QRtB3zxA3yB+FLsT1hx0va6xCHpX3QO2gBsyHCyVafFMrg3c/7IIWkDLngJxFgz6DLiA G4ld1QK/jsYqfP2GIMH1mFdjY+iagG4DqOsjip479HCWAptpNxSOCL6z3qxCU8MCz8iNOtZk DYXQWVscM5qgYSn+fmMM2qN+eoWlnCGVURZZLDjg387S2E1jT/dNTOsM/IqQj+ZROUZuRcF7 0RTtuU5q1HnbRNwy+23xeoSGuwmLQ2UsUk7Q5CnrjYfiPo3wHze8avK95JBoSd+WIRmV3uoO rXCoYOIRlDhg9XJTrbnQ3Ot5zOa0Y9c4IpyAlut6mDtxtKXr4+8OzjSVFww7tIwadTK3wDQv Bus4jxHjS6dz1g2ypT65qnHen6mUUH63lhzewqO9peAHJ0SLrQARAQABzTBUb21pIFZhbGtl aW5lbiA8dG9taS52YWxrZWluZW5AaWRlYXNvbmJvYXJkLmNvbT7CwY4EEwEIADgWIQTEOAw+ ll79gQef86f6PaqMvJYe9QUCX/HruAIbAwULCQgHAgYVCgkICwIEFgIDAQIeAQIXgAAKCRD6 PaqMvJYe9WmFD/99NGoD5lBJhlFDHMZvO+Op8vCwnIRZdTsyrtGl72rVh9xRfcSgYPZUvBuT VDxE53mY9HaZyu1eGMccYRBaTLJSfCXl/g317CrMNdY0k40b9YeIX10feiRYEWoDIPQ3tMmA 0nHDygzcnuPiPT68JYZ6tUOvAt7r6OX/litM+m2/E9mtp8xCoWOo/kYO4mOAIoMNvLB8vufi uBB4e/AvAjtny4ScuNV5c5q8MkfNIiOyag9QCiQ/JfoAqzXRjVb4VZG72AKaElwipiKCWEcU R4+Bu5Qbaxj7Cd36M/bI54OrbWWETJkVVSV1i0tghCd6HHyquTdFl7wYcz6cL1hn/6byVnD+ sR3BLvSBHYp8WSwv0TCuf6tLiNgHAO1hWiQ1pOoXyMEsxZlgPXT+wb4dbNVunckwqFjGxRbl Rz7apFT/ZRwbazEzEzNyrBOfB55xdipG/2+SmFn0oMFqFOBEszXLQVslh64lI0CMJm2OYYe3 PxHqYaztyeXsx13Bfnq9+bUynAQ4uW1P5DJ3OIRZWKmbQd/Me3Fq6TU57LsvwRgE0Le9PFQs dcP2071rMTpqTUteEgODJS4VDf4lXJfY91u32BJkiqM7/62Cqatcz5UWWHq5xeF03MIUTqdE qHWk3RJEoWHWQRzQfcx6Fn2fDAUKhAddvoopfcjAHfpAWJ+ENc7BTQROprNHARAAx0aat8GU hsusCLc4MIxOQwidecCTRc9Dz/7U2goUwhw2O5j9TPqLtp57VITmHILnvZf6q3QAho2QMQyE DDvHubrdtEoqaaSKxKkFie1uhWNNvXPhwkKLYieyL9m2JdU+b88HaDnpzdyTTR4uH7wk0bBa KbTSgIFDDe5lXInypewPO30TmYNkFSexnnM3n1PBCqiJXsJahE4ZQ+WnV5FbPUj8T2zXS2xk 0LZ0+DwKmZ0ZDovvdEWRWrz3UzJ8DLHb7blPpGhmqj3ANXQXC7mb9qJ6J/VSl61GbxIO2Dwb xPNkHk8fwnxlUBCOyBti/uD2uSTgKHNdabhVm2dgFNVuS1y3bBHbI/qjC3J7rWE0WiaHWEqy UVPk8rsph4rqITsj2RiY70vEW0SKePrChvET7D8P1UPqmveBNNtSS7In+DdZ5kUqLV7rJnM9 /4cwy+uZUt8cuCZlcA5u8IsBCNJudxEqBG10GHg1B6h1RZIz9Q9XfiBdaqa5+CjyFs8ua01c 9HmyfkuhXG2OLjfQuK+Ygd56mV3lq0aFdwbaX16DG22c6flkkBSjyWXYepFtHz9KsBS0DaZb 4IkLmZwEXpZcIOQjQ71fqlpiXkXSIaQ6YMEs8WjBbpP81h7QxWIfWtp+VnwNGc6nq5IQDESH mvQcsFS7d3eGVI6eyjCFdcAO8eMAEQEAAcLBXwQYAQIACQUCTqazRwIbDAAKCRD6PaqMvJYe 9fA7EACS6exUedsBKmt4pT7nqXBcRsqm6YzT6DeCM8PWMTeaVGHiR4TnNFiT3otD5UpYQI7S suYxoTdHrrrBzdlKe5rUWpzoZkVK6p0s9OIvGzLT0lrb0HC9iNDWT3JgpYDnk4Z2mFi6tTbq xKMtpVFRA6FjviGDRsfkfoURZI51nf2RSAk/A8BEDDZ7lgJHskYoklSpwyrXhkp9FHGMaYII m9EKuUTX9JPDG2FTthCBrdsgWYPdJQvM+zscq09vFMQ9Fykbx5N8z/oFEUy3ACyPqW2oyfvU CH5WDpWBG0s5BALp1gBJPytIAd/pY/5ZdNoi0Cx3+Z7jaBFEyYJdWy1hGddpkgnMjyOfLI7B CFrdecTZbR5upjNSDvQ7RG85SnpYJTIin+SAUazAeA2nS6gTZzumgtdw8XmVXZwdBfF+ICof 92UkbYcYNbzWO/GHgsNT1WnM4sa9lwCSWH8Fw1o/3bX1VVPEsnESOfxkNdu+gAF5S6+I6n3a ueeIlwJl5CpT5l8RpoZXEOVtXYn8zzOJ7oGZYINRV9Pf8qKGLf3Dft7zKBP832I3PQjeok7F yjt+9S+KgSFSHP3Pa4E7lsSdWhSlHYNdG/czhoUkSCN09C0rEK93wxACx3vtxPLjXu6RptBw 3dRq7n+mQChEB1am0BueV1JZaBboIL0AGlSJkm23kw== In-Reply-To: <4d9e340e-2ae7-495b-8623-0d10398e1c3d@xs4all.nl> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Hi Hans, On 24/10/2024 11:20, Hans Verkuil wrote: > Hi Tomi, > > I know this driver is already merged, but while checking for drivers that use > q->max_num_buffers I stumbled on this cfe code: > > > >> +/* >> + * vb2 ops >> + */ >> + >> +static int cfe_queue_setup(struct vb2_queue *vq, unsigned int *nbuffers, >> + unsigned int *nplanes, unsigned int sizes[], >> + struct device *alloc_devs[]) >> +{ >> + struct cfe_node *node = vb2_get_drv_priv(vq); >> + struct cfe_device *cfe = node->cfe; >> + unsigned int size = is_image_node(node) ? >> + node->vid_fmt.fmt.pix.sizeimage : >> + node->meta_fmt.fmt.meta.buffersize; >> + >> + cfe_dbg(cfe, "%s: [%s] type:%u\n", __func__, node_desc[node->id].name, >> + node->buffer_queue.type); >> + >> + if (vq->max_num_buffers + *nbuffers < 3) >> + *nbuffers = 3 - vq->max_num_buffers; > > This makes no sense: max_num_buffers is 32, unless explicitly set when vb2_queue_init > is called. So 32 + *nbuffers is never < 3. > > If the idea is that at least 3 buffers should be allocated by REQBUFS, then set > q->min_reqbufs_allocation = 3; before calling vb2_queue_init and vb2 will handle this > for you. > > Drivers shouldn't modify *nbuffers, except in very rare circumstances, especially > since the code is almost always wrong. Indeed, the code doesn't make sense. I have to say I don't know what was the intent here, but I think "at least 3 buffers should be allocated by REQBUFS" is the likely explanation. I think the hardware should work with even just a single buffer, so is it then fine to not set either q->min_queued_buffers nor q->min_reqbufs_allocation before calling vb2_queue_init()? This seems to result in REQBUFS giving at least two buffers. Tomi > > Regards, > > Hans > >> + >> + if (*nplanes) { >> + if (sizes[0] < size) { >> + cfe_err(cfe, "sizes[0] %i < size %u\n", sizes[0], size); >> + return -EINVAL; >> + } >> + size = sizes[0]; >> + } >> + >> + *nplanes = 1; >> + sizes[0] = size; >> + >> + return 0; >> +} >