From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mitch Bradley Subject: Re: Device tree bindings for linux ramoops use Date: Thu, 05 Jan 2012 21:22:08 -1000 Message-ID: <4F06A120.8080505@firmworks.com> References: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org Sender: devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org To: Olof Johansson Cc: Marco Stornelli , devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org, Rob Herring List-Id: devicetree@vger.kernel.org On 1/5/2012 6:39 PM, Olof Johansson wrote: > Hi, > > I'm considering how to best describe the data that ramoops needs in > the device tree. > > The idea is really about describing a memory area that is (likely to > be) nonvolatile across reboots. Said area is not to be included in the > regular memory map of the system (i.e. not covered by /memory). > > I have a few options on where to do it. It's not really a hardware > device per se, so it's a gray area for the device tree alltogether. > > How about something like? > > compatible = "linux,ramoops" > linux,ramoops-start = > linux,ramoops-size = ... > linux,ramoops-record-size = ... > linux,ramoops-include-oopses = ... (this one is a bit of a corner > case, it's truly a software setting -- probably leave it out) > > Anybody have a better idea? If it is addressable, it should appear as a device node underneath the node that creates the address space in which it appears, and the start and size should be described by a "reg" property. > > I could do a platform-specific binding that describes the nonvolatile > ram area as a separate "device", and then have some platform code that > translates that into the ramoops platform pdata parameters (since it > can't really be assumed that ramoops has ownership of the whole > area/device). That seems pretty awkward too though, and I'm not sure > it buys us a whole lot. > > > -Olof > _______________________________________________ > devicetree-discuss mailing list > devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org > https://lists.ozlabs.org/listinfo/devicetree-discuss >