From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752060AbcFUUld (ORCPT ); Tue, 21 Jun 2016 16:41:33 -0400 Received: from mail-oi0-f67.google.com ([209.85.218.67]:36273 "EHLO mail-oi0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751639AbcFUUla (ORCPT ); Tue, 21 Jun 2016 16:41:30 -0400 Date: Tue, 21 Jun 2016 15:41:21 -0500 From: Rob Herring To: Kees Cook Cc: LKML , Greg Hackmann , Arnd Bergmann , Markus Pargmann , Olof Johansson , Brian Norris , Anton Vorontsov , Colin Cross , Lee Campbell , Tony Luck , "devicetree@vger.kernel.org" , "linux-doc@vger.kernel.org" Subject: Re: [PATCH v4 0/1] pstore/ram: add Device Tree bindings Message-ID: <20160621204121.GA1595@rob-hp-laptop> References: <1465599059-22665-1-git-send-email-keescook@chromium.org> <20160614215914.GA16454@rob-hp-laptop> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, Jun 14, 2016 at 09:40:47PM -0700, Kees Cook wrote: > On Tue, Jun 14, 2016 at 2:59 PM, Rob Herring wrote: > > On Fri, Jun 10, 2016 at 03:50:58PM -0700, Kees Cook wrote: > >> This is a "v4" of Greg Hackmann's DT bindings for ramoops. This is > >> what I'm going to land in the pstore tree unless there are strong and > >> convincing arguments against it. :) > >> > >> I made a number of changes based people's feedback, and I want to get > >> it unblocked. This patch is already carried by Android, and it doesn't > >> need to be out of tree. > >> > >> To respond to Arnd's comment: I like this as the ramoops node, not the > >> pstore node, since it describes the ramoops backend, not the pstore > >> subsystem, which has different controls, and can only have one backend > >> at a time. So it doesn't make sense to me to have this have a redundant > >> extra pstore node, since the very presence of ramoops implies pstore. > > > > Either I don't follow or you don't get Arnd's comment... > > > > IIRC, his suggestion which I agree with was to remove the memory-region > > phandle and just move all the properties into the reserved memory node > > directly. This simplifies things such that we are just describing > > properties of a chunk of memory rather than a Linux specific node for > > virtual driver. > > Ah! Okay, I'm a DT newbie, so I think I misunderstood Arnd. :) If it's > easy, can you create a patch for that against the v4 I sent of Greg's > patch? I'm not sure how to do what you're suggesting. :) While I want to see this merged, I'm not going to get to anything soon. So here's a DT example of what I mean. This will in addition need an of_platform_populate call on the /reserved-memory node to get the platform device created. {/ reserved-memory { #address-cells = <1>; #size-cells = <1>; ranges; /* global autoconfigured region for contiguous allocations */ linux,cma { compatible = "shared-dma-pool"; reusable; size = <0x4000000>; alignment = <0x2000>; linux,cma-default; }; ramoops@78000000 { compatible = "ramoops"; reg = <0x78000000 0x8000>; record-size = <0x4000>; console-size = <0x4000> }; }; }; Rob