From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from de01egw01.freescale.net (de01egw01.freescale.net [192.88.165.102]) by ozlabs.org (Postfix) with ESMTP id 582EBDDE37 for ; Thu, 15 Feb 2007 08:58:08 +1100 (EST) Message-ID: <45D385E9.4020808@freescale.com> Date: Wed, 14 Feb 2007 15:58:01 -0600 From: Timur Tabi MIME-Version: 1.0 To: Benjamin Herrenschmidt Subject: Re: [PATCH] powerpc: delete boot-cpu and chosen nodes from all DTS files References: <1171409687840-git-send-email-timur@freescale.com> <1171411075.20192.116.camel@localhost.localdomain> <45D29AE5.7090004@freescale.com> <1171430877.20192.133.camel@localhost.localdomain> <45D29EB1.5060801@freescale.com> <1171431334.20192.138.camel@localhost.localdomain> <45D316CD.9070901@freescale.com> <1171486473.20192.147.camel@localhost.localdomain> <45D378F4.3040003@freescale.com> <1171487822.20192.163.camel@localhost.localdomain> In-Reply-To: <1171487822.20192.163.camel@localhost.localdomain> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Cc: linuxppc-dev@ozlabs.org, paulus@samba.org, Stuart Yoder List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Benjamin Herrenschmidt wrote: > In case somebody wants to use something else than uboot ? I'd like the > base structure of the mandatory nodes to be there. /chosen is mandatory, > so it should be there. I just posted a new patch that just deletes linux,boot-cpu and leaves the 'chosen' node alone. However, there is a valid reason for *not* having a 'chosen' node in the DTS. Currently, U-Boot does not update the existing 'chosen' node. Instead, it creates a new one. This means that if one existed in the DTS, then there would be *two* in the device tree that is passed to the kernel. There is no way to guarantee that the kernel will use the right one. Of course, the real solution to this problem is to fix U-Boot. However, there isn't any signed up to do that, and even if someone posted a patch right now, there's no telling when it will get applied. And even if it got applied today, all current U-Boot installations would be broken. Many of these systems will never be updated. Therefore, I would say that having a 'chosen' node in the DTS is actually a *bad* thing, on systems that use U-Boot. Another work-around would be to update the compiler to delete the chosen node when it builds the DTB. That's not a bad idea, I think, but until that feature is implemented, the DTS files should not have a 'chosen' node. -- Timur Tabi Linux Kernel Developer @ Freescale