From mboxrd@z Thu Jan 1 00:00:00 1970 From: Rafal Jaworowski Subject: Re: PCI bus node location Date: Wed, 11 Nov 2009 15:17:52 +0100 Message-ID: References: <20091110031218.GG26042@yookeroo.seuss> <839C8AA0-A8B5-434E-9175-16D2B84D74BD@semihalf.com> <20091110234412.GA3235@yookeroo.seuss> Mime-Version: 1.0 (Apple Message framework v1076) Content-Type: text/plain; charset="us-ascii"; Format="flowed"; DelSp="yes" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <20091110234412.GA3235-787xzQ0H9iRg7VrjXcPTGA@public.gmane.org> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org Errors-To: devicetree-discuss-bounces+gldd-devicetree-discuss=m.gmane.org-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org To: David Gibson Cc: devicetree-discuss-uLR06cmDAlY/bJ5BZ2RsiQ@public.gmane.org List-Id: devicetree@vger.kernel.org On 2009-11-11, at 00:44, David Gibson wrote: > On Tue, Nov 10, 2009 at 05:55:33PM +0100, Rafal Jaworowski wrote: >> On 2009-11-10, at 04:12, David Gibson wrote: >>> On Mon, Nov 09, 2009 at 07:36:57PM -0700, Grant Likely wrote: >>>> On Mon, Nov 9, 2009 at 12:20 PM, Rafal Jaworowski > [snip] >>> Right. >>> >>> Under the new scheme, the "soc" node is really a historical >>> misnomer - >>> it represents just the things within the IMMR, not everything on the >>> SoC. A number of chips also have the localbus controller as a >>> separate node, likewise within the SoC but not within the IMMR, so >>> not >>> a child of the soc node. >> >> Hm, how do we know whether something belongs under the IMMR/CCSR >> node or not (even though it physically sits there :-)? > > Well, the basic criterion is whether its registers are relocated with > the rest of the IMMR. Which would cover the PCI control registers, of > course, but they're not there for the reasons given. Yes, it's kind > of nasty. It seems like the soc/simple-bus node is currently a rather arbitrary subset of peripherals available through SOC internal registers range. My concern is that without clear grouping criteria this is quite confusing. >> Is the 'soc' node going to be named something less confusing then? > > I think it should, but it's difficult to change because u-boot has > dependencies on it. I think there are a few newer trees where it's > named IMMR. So is device_type = "soc" deprecated now for new trees, and for this kind of a bus node the only legit differentiator is the compatible = "simple-bus" prop? BTW: in ePAPR examples there is device_type = "simple-bus" in a 8572 soc node, is this a bug or a leftover? Rafal