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 phobos.denx.de (phobos.denx.de [85.214.62.61]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 1F4EAC47DDB for ; Tue, 23 Jan 2024 00:59:33 +0000 (UTC) Received: from h2850616.stratoserver.net (localhost [IPv6:::1]) by phobos.denx.de (Postfix) with ESMTP id BE4E887895; Tue, 23 Jan 2024 01:59:31 +0100 (CET) Authentication-Results: phobos.denx.de; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: phobos.denx.de; spf=pass smtp.mailfrom=u-boot-bounces@lists.denx.de Received: by phobos.denx.de (Postfix, from userid 109) id 9A91B87B41; Tue, 23 Jan 2024 01:59:30 +0100 (CET) Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by phobos.denx.de (Postfix) with ESMTP id 522D887895; Tue, 23 Jan 2024 01:59:28 +0100 (CET) Authentication-Results: phobos.denx.de; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: phobos.denx.de; spf=pass smtp.mailfrom=andre.przywara@arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 119101FB; Mon, 22 Jan 2024 17:00:13 -0800 (PST) Received: from minigeek.lan (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id CE2983F762; Mon, 22 Jan 2024 16:59:23 -0800 (PST) Date: Tue, 23 Jan 2024 00:58:34 +0000 From: Andre Przywara To: Tom Rini Cc: Sumit Garg , u-boot@lists.denx.de, u-boot-amlogic@groups.io, u-boot-custodians@lists.denx.de, sjg@chromium.org, robh+dt@kernel.org, krzysztof.kozlowski+dt@linaro.org, conor@kernel.org, neil.armstrong@linaro.org, caleb.connolly@linaro.org, ff@shokubai.tech, daniel.thompson@linaro.org, dgilmore@fedoraproject.org, pbrobinson@gmail.com, ilias.apalodimas@linaro.org, maxim.uvarov@linaro.org, b.galvani@gmail.com, xypron.glpk@gmx.de, michal.simek@amd.com, seanga2@gmail.com, rasmus.villemoes@prevas.dk, peng.fan@nxp.com, jh80.chung@samsung.com, rfried.dev@gmail.com, marex@denx.de, mibodhi@gmail.com, bb@ti.com, mark.kettenis@xs4all.nl Subject: Re: [PATCH v4 00/11] An effort to bring DT bindings compliance within U-Boot Message-ID: <20240123005834.4ab47bf5@minigeek.lan> In-Reply-To: <20240122164959.GN3652023@bill-the-cat> References: <20240110103547.719757-1-sumit.garg@linaro.org> <20240122114515.760e9cd3@donnerap.manchester.arm.com> <20240122164959.GN3652023@bill-the-cat> Organization: Arm Ltd. X-Mailer: Claws Mail 4.2.0 (GTK 3.24.31; x86_64-slackware-linux-gnu) MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit X-BeenThere: u-boot@lists.denx.de X-Mailman-Version: 2.1.39 Precedence: list List-Id: U-Boot discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: u-boot-bounces@lists.denx.de Sender: "U-Boot" X-Virus-Scanned: clamav-milter 0.103.8 at phobos.denx.de X-Virus-Status: Clean On Mon, 22 Jan 2024 11:49:59 -0500 Tom Rini wrote: Hi Tom, > On Mon, Jan 22, 2024 at 11:45:15AM +0000, Andre Przywara wrote: > > On Wed, 10 Jan 2024 16:05:36 +0530 > > Sumit Garg wrote: > > > > Hi, > > > > I certainly welcome this more automatic synchronisation of the DTs, > > however have one comment about the upcoming sync process: > > > > > ... > > > However, Linux kernel DT maintainers proposed [2] for U-Boot to rather > > > use devicetree-rebasing repo [3] which is a forked copy from Linux > > > kernel for DT source files as well as bindings. It is tagged at every > > > Linux kernel major release or intermideate release candidates. So here I > > > have tried to reuse that to bring DT bingings compliance as well as a > > > standard way to maintain a regular sync of DT source files with Linux > > > kernel. > > > > > > In order to maintain devicetree files sync, U-Boot will maintains a Git > > > subtree for devicetee-rebasing repo as `dts/upstream` sub-directory. > > > U-Boot will regularly sync `dts/upstream/` subtree whenever the next window > > > opens with the next available kernel major release. > > > > I hope this doesn't need to stay that restricted? Can we either sync more > > often, or at least on the kernel's -rc1, and not only on a "full" release? > > > > The reason I ask is that we have a chicken-egg problem here: without a DT > > merged into the kernel tree, no U-Boot board support can be merged. And > > without U-Boot support, we cannot boot a kernel, at least not in the > > canonical way. > > > > Since the U-Boot and kernel merge windows are not in phase, for sunxi I try > > to sync the kernel DTs either as early as possible (-rc1, sometimes even > > before, when the maintainers have merged them into their tree), or > > sometimes "out of season", if a board defconfig patch is coming up. > > > > Otherwise new board support, which typically has a very low regression risk > > for the rest of the code base, would need to be delayed until the next > > release. In the worst case the U-Boot merge windows opens one week before > > a kernel release, then new boards need to wait three months? > > Would it be to bad to bring in board X with OF_UPSTREAM=n for one U-Boot > release, and then with the next one switch to OF_UPSTREAM=y (and delete > the dts from arch/) for the next release, when we would have gotten back > in sync? Ah, I didn't look into the actual patches, but if this provision is there, that sounds surely acceptable. It might still be good to sync earlier than the .0 kernel release: if it appears in Linus' tree, it had already seen a good share of review and testing. And with the U-Boot releases being always further away than the next kernel release, we could pull fixes still in time. So we could pick the latest -rc (or .0 release, whichever is more recent) when the U-Boot merge window opens? Cheers, Andre