From mboxrd@z Thu Jan 1 00:00:00 1970 From: Frank Rowand Subject: Re: devicetree repository separation/migration Date: Wed, 19 Feb 2014 12:16:02 -0800 Message-ID: <53051102.8060801@gmail.com> References: <20140217180544.GU7862@titan.lakedaemon.net> <20140218155750.GS17250@pengutronix.de> <20140218181854.GB7862@titan.lakedaemon.net> <20140219090854.GW17250@pengutronix.de> Reply-To: frowand.list-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20140219090854.GW17250-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org> Sender: devicetree-compiler-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Sascha Hauer Cc: Tim Bird , Olof Johansson , Jason Cooper , Grant Likely , Rob Herring , Ian Campbell , Pawel Moll , Mark Rutland , Kumar Gala , Rob Landley , "devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org" , devicetree-spec-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, devicetree-compiler-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: devicetree@vger.kernel.org On 2/19/2014 1:08 AM, Sascha Hauer wrote: > On Tue, Feb 18, 2014 at 02:44:15PM -0800, Tim Bird wrote: >> I'm not in favor of separating the device tree information from the kernel. >> >> If we switch, then whatever synchronization issues other projects >> are having now with synching with the device tree info from the kernel will >> just then become the problem of the kernel developers, who will then >> have to sync with the device tree info from another repository. If the >> sync issues can't be solved now for them, why or how would it be solved >> post-separation for us? (It sounds like a zero-sum game of pain transfer >> to me.) >> >> I'm relatively unfamiliar with the arguments. Can someone provide >> a brief list of reasons this is needed, and how the inconvenience to Linux >> kernel developers will be minimized, should it proceed? > > One of the reasons for doing devicetrees is to separate the hardware > description from the code so that: > - Other OSes (and bootloaders) can use the same description to start on > a given hardware > - A generic Kernel can be started on any hardware > - A hardware describes itself, makes itself more introspecitve so we can > go away from very specialized kernels Tim knows this ^^^^. He was asking for the arguments for moving dts files out of the linux kernel source tree. Can you answer his question? > > This can't be archieved when the devicetrees are constantly changing. So > we should separate the devicetrees from the kernel to make them usable > for other projects, but also to make the kernel more universally usable. > Compatibility issues will be far more obvious when kernel and > devicetrees are separated, but this will make people behave more > carefully and helps making the devicetree interface more stable and > usable. So come up with a way of making dts files more stable while still in the linux kernel source tree. Moving the files to another repository is not going to magically make them more stable. > > Just to make that sure: It's an illusion that future kernels will be > 100% compatible with old devicetrees, but we should at least follow a > best effort approach. If they are compatible enough to at least bring up > the hardware then this is at least enough to install a better > devicetree. > > Sascha > -Frank -- To unsubscribe from this list: send the line "unsubscribe devicetree-compiler" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html