From mboxrd@z Thu Jan 1 00:00:00 1970 From: dwmw2@infradead.org (David Woodhouse) Date: Fri, 26 Jul 2013 14:41:10 +0100 Subject: [Ksummit-2013-discuss] DT bindings as ABI [was: Do we have people interested in device tree janitoring / cleanup?] In-Reply-To: <20130726132709.GH29916@titan.lakedaemon.net> References: <20130725175702.GC22291@e106331-lin.cambridge.arm.com> <51F168FC.9070906@wwwdotorg.org> <20130725182920.GA24955@e106331-lin.cambridge.arm.com> <20130725184834.GA8296@netboy> <20130725213753.GC17616@obsidianresearch.com> <20130726080115.GA5436@netboy> <1374831744.2923.42.camel@shinybook.infradead.org> <20130726130927.GC4219@netboy> <20130726132709.GH29916@titan.lakedaemon.net> Message-ID: <1374846070.14574.92.camel@i7.infradead.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Fri, 2013-07-26 at 09:27 -0400, Jason Cooper wrote: > > The other dynamic change that bears mentioning here is attributes which > have been configured by the bootloader. For example, in mvebu, we have > the Schrodinger's Cat register. It allows you to reconfigure the base > address of the registers from *within* that register range. If the > bootloader does this, the DT needs to be updated to reflect the current > hardware configuration. Otherwise, the kernel is stuck poking around at > memory addresses hoping to find something sane. > > But this falls into the same category as you mentioned, but outside of > chosen {};. Yeah, /chosen was given as an example of stuff that's almost *exclusively* "configuration" stuff. But there's plenty outside there that can reasonably change. It's OK to change the data, and of *course* the base address reported in the DT should actually match reality *today*, if it changes on the fly. It's not OK to change the *schema* in which those data are expressed. That's the ABI we're talking about. -- dwmw2 -------------- next part -------------- A non-text attachment was scrubbed... Name: smime.p7s Type: application/x-pkcs7-signature Size: 5745 bytes Desc: not available URL: