From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752242AbbCKRhV (ORCPT ); Wed, 11 Mar 2015 13:37:21 -0400 Received: from muru.com ([72.249.23.125]:36569 "EHLO muru.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750769AbbCKRhS (ORCPT ); Wed, 11 Mar 2015 13:37:18 -0400 Date: Wed, 11 Mar 2015 10:32:13 -0700 From: Tony Lindgren To: Suman Anna Cc: Dave Gerlach , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-omap@vger.kernel.org, devicetree@vger.kernel.org, Ohad Ben-Cohen , Kevin Hilman , Felipe Balbi Subject: Re: [PATCH v2 2/2] ARM: dts: am33xx: Move wkup_m3 node to soc node and add ranges Message-ID: <20150311173212.GC5264@atomide.com> References: <1425528742-3087-1-git-send-email-d-gerlach@ti.com> <1425528742-3087-3-git-send-email-d-gerlach@ti.com> <20150305154039.GD13520@atomide.com> <54F88849.1090708@ti.com> <20150305165727.GE13520@atomide.com> <54FE33CA.4090709@ti.com> <20150310160919.GQ5264@atomide.com> <54FF4C32.5070106@ti.com> <20150311162635.GZ5264@atomide.com> <550078D5.7080700@ti.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <550078D5.7080700@ti.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org * Suman Anna [150311 10:18]: > On 03/11/2015 11:26 AM, Tony Lindgren wrote: > > * Dave Gerlach [150310 12:55]: > >> Suman and I have been looking at this together, so I can comment here. An > >> implementation like this is what Suman is referring to: > >> > >> + l4_wkup: l4_wkup@44c00000 { > >> + compatible = "am335-l4-wkup", "simple-bus"; > >> + #address-cells = <2>; > >> + #size-cells = <1>; > >> + ranges = <0 0 0x44c00000 0x100000>, > >> + <1 0x0 0x44d00000 0x4000>, > >> + <2 0x80000 0x44d80000 0x2000>; > > Actually, this would be slightly different, something like > + ranges = <0 0 0x44c00000 0x100000>, > + <1 0 0x44d00000 0x100000>, > + <2 0 0x44e00000 0x4000>, > + <3 0 0x44e10000 0x2000>; > > and the M3 DMEM entry below will be adjusted as <1 0x80000 0x2000>. > > >> + > >> + wkup_m3: wkup_m3@1,0 { > >> + compatible = "ti,am3353-wkup-m3"; > >> + reg = <1 0x0 0x4000>, /* M3 UMEM */ > >> + <2 0x80000 0x2000>; /* M3 DMEM */ > >> + > >> + ti,hwmods = "wkup_m3"; > >> + ti,pm-firmware = "am335x-pm-firmware.elf"; > >> + }; > >> + }; > >> + > >> > >> The of_* layer automatically translates everything so the pdata-quirks can still > >> match based on wkup_m3@44d00000. The existing wkup_m3_rproc driver works almost > >> entirely as is with this, all cpu addresses are read and mapped correctly but > >> the driver no longer will read the actual device addresses correctly which we > >> need for understanding where to load the firmware sections. > > > > OK. I still don't quite understand how these additional ranges make sense > > for other drivers connected to the l4_wkup. For wkup_m3, it makes sense if > > it allows you to translate directly to the m3 address space, but is that > > really the case here? Maybe you should have the ranges in wkup_m3 instead > > if you want addresses for the m3? > > The idea is to introduce an additional address element (first cell in > ranges) so that the immediate child nodes bus address is referenced as 0 > (second cell) for translation for their child nodes. This is the > approach used by the current scm node in Tero's series for OMAP4+. This > will work tomorrow if we move the prcm, scrm node under l4_wkup with > changes only in those nodes, and have their child nodes reg properties > unchanged. I guess you can see the difference between the following two > patches from Tero's PRCM series, > https://patchwork.kernel.org/patch/5882831/ & > https://patchwork.kernel.org/patch/5882841/ Well I just commented on Tero on that regarding the dra7 patch. I think we need to have separate scm instances for scm_device, scm_core and scm_wkup instead of doing multiple ranges. This based on looking at for example 5432 TRM "Figure 18-1. Control Module Overview". But here I think it's a different issue. You want to use ranges for getting the m3 address space for the firmware? I'm not convinced we should complicate the ranges for all l4_wkup drivers because of that. Regards, Tony