From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0F17DC4332F for ; Wed, 23 Nov 2022 16:34:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238106AbiKWQeA (ORCPT ); Wed, 23 Nov 2022 11:34:00 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59228 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S237578AbiKWQd7 (ORCPT ); Wed, 23 Nov 2022 11:33:59 -0500 Received: from mail-ed1-x531.google.com (mail-ed1-x531.google.com [IPv6:2a00:1450:4864:20::531]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9F18E27DC1 for ; Wed, 23 Nov 2022 08:33:58 -0800 (PST) Received: by mail-ed1-x531.google.com with SMTP id x102so25658007ede.0 for ; Wed, 23 Nov 2022 08:33:58 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ffwll.ch; s=google; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date:from:to :cc:subject:date:message-id:reply-to; bh=vQ8nm6+WyKeJ4NSkaQqYp2teKXcJsmSR2OlnL5nJCng=; b=LTaFlYw0Pm8utr+zS/UXk0FrQTM6S4ZrXc7dE2wTm7nTS9rZ8ucryQq8shd4RhG9kc r71lmcHkASsmyfN1/CaYdQBfvLaqjDdGshMjTLB6NY6FGg2bX5UtJmqsuDDXnT6Fjk47 ERYCfdANhr7rbF2w+N6ES5m3u7CEOUYzqV9sw= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-transfer-encoding:content-disposition :mime-version:references:message-id:subject:cc:to:from:date :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=vQ8nm6+WyKeJ4NSkaQqYp2teKXcJsmSR2OlnL5nJCng=; b=aExchVgu7P44VOVoXCwVmQl3ueEKYvH0q1O+IfDSolosL4kmrx2ZILrxaVKy5pQisn IF//8S4qQTMPqFa7Ol0JIhGl91wRYVNIjzuwQOvDRyE6FB+P2UBXmKOwmz4tVdasMvEN qNfPT+0LQkx0c4ZzSL3eAEjvKgjvohG/yFLnpl8oC0dV9BYY75XFqJfZqJCgRkQrnBYe y5oPmBQT/Y1m7LtMFnKNy9c4mcaSR4m31Z4luNcyX4yIL6aIYEmSh48h1SVLEJ7HOA5b qS9REJwS5Y7o7S8K38RQxUt/m34XyBVcWkyqIBIvQnb1PYC1lRG8+dkwr3NExr5WKKdv uUPw== X-Gm-Message-State: ANoB5pkPtgLGW88/mh+KcOjiBgW+A9D9FWYkmQEncY4lYHJZn1jTLmZj hMXKaq5j9TQ9peDFdpXr5ds6Bg== X-Google-Smtp-Source: AA0mqf4Enr1qM6eoPL9aF0axGh9DxgF+M99FiwcrAbYtdUzrx2lqXegdh98KtI4edE32ukwrcdXh6Q== X-Received: by 2002:a05:6402:3719:b0:461:4f34:d8f4 with SMTP id ek25-20020a056402371900b004614f34d8f4mr26937012edb.144.1669221236923; Wed, 23 Nov 2022 08:33:56 -0800 (PST) Received: from phenom.ffwll.local (212-51-149-33.fiber7.init7.net. [212.51.149.33]) by smtp.gmail.com with ESMTPSA id ez6-20020a056402450600b004643f1524f3sm7770969edb.44.2022.11.23.08.33.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 23 Nov 2022 08:33:56 -0800 (PST) Date: Wed, 23 Nov 2022 17:33:54 +0100 From: Daniel Vetter To: Pekka Paalanen Cc: Christian =?iso-8859-1?Q?K=F6nig?= , Daniel Vetter , Rob Clark , Nicolas Dufresne , Tomasz Figa , Lucas Stach , Daniel Stone , sumit.semwal@linaro.org, dri-devel@lists.freedesktop.org, linaro-mm-sig@lists.linaro.org, linux-media@vger.kernel.org Subject: Re: Try to address the DMA-buf coherency problem Message-ID: References: <0abc6efddb8dfc1888de15a1bedaaac6688fd078.camel@pengutronix.de> <1e2a6750-9849-e9ee-69d6-e4bfdcfb64f3@gmail.com> <346d6ad023ef8697aafd93ac1b100890f3637e44.camel@ndufresne.ca> <20221123103338.238571e1@eldfell> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <20221123103338.238571e1@eldfell> X-Operating-System: Linux phenom 5.19.0-2-amd64 Precedence: bulk List-ID: X-Mailing-List: linux-media@vger.kernel.org On Wed, Nov 23, 2022 at 10:33:38AM +0200, Pekka Paalanen wrote: > On Tue, 22 Nov 2022 18:33:59 +0100 > Christian König wrote: > > > We should have come up with dma-heaps earlier and make it clear that > > exporting a DMA-buf from a device gives you something device specific > > which might or might not work with others. > > > > Apart from that I agree, DMA-buf should be capable of handling this. > > Question left is what documentation is missing to make it clear how > > things are supposed to work? > > Perhaps somewhat related from Daniel Stone that seems to have been > forgotten: > https://lore.kernel.org/dri-devel/20210905122742.86029-1-daniels@collabora.com/ > > It aimed mostly at userspace, but sounds to me like the coherency stuff > could use a section of its own there? Hm yeah it would be great to land that and then eventually extend. Daniel? -Daniel -- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch