From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Message-ID: <4612EA16.7070102@am.sony.com> Date: Tue, 03 Apr 2007 16:58:14 -0700 From: Geoff Levand MIME-Version: 1.0 To: Arnd Bergmann Subject: Re: [Cbe-oss-dev] [PATCH] Ignore memory listed in PS3 device tree References: <1175208237.3122.78.camel@pmac.infradead.org> <1175636904.10567.8.camel@shinybook.infradead.org> <4612D8FE.1070400@am.sony.com> <200704040055.36173.arnd@arndb.de> In-Reply-To: <200704040055.36173.arnd@arndb.de> Content-Type: text/plain; charset=UTF-8 Cc: linuxppc-dev list , nhorman@redhat.com, David Woodhouse , cbe-oss-dev@ozlabs.org, Ben Collins List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Arnd Bergmann wrote: > On Wednesday 04 April 2007, Geoff Levand wrote: >> So there are really two answers, one is that having the boot memory in= the >> DT hasn't changed, I just haven't finished that part yet. =EF=BF=BDThe= other is that >> we get the amount of memory at runtime because it is a dynamic resourc= e, and >> cannot be known at DT compile time. >=20 > But the device tree can easily be modified before entering the new kern= el, > when the kboot kernel allocates all the memory it can get, it just need= s > to list it in the device tree in some preallocated device node. Yes, but boot mem is not allocated by the guest, it is allocated by the p= olicy module. The guest can only query how much boot mem has been allocated fo= r it. This can be done by the bootloader, or the kernel itself, if done ea= rly enough. That info needs to be added to the DT before the kernel sets up = its boot mem structures. My current plan is to do it in the bootloader, sinc= e there is not a platform hook in the current powerpc arch code that is ear= ly enough. But you seem to say we can do something in the first stage kernel and pas= s some info to the second stage kernel? The trouble with that is that when the kernel is used as a first stage, where does the info come from? I wa= nt to have a single kernel that can be either programmed into flash or loade= d by kexec. For that to work the DT setup must be done in the wrapper, or the kernel itself. -Geoff