From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Sat, 10 Feb 2007 09:41:42 +1100 From: David Gibson To: Jerry Van Baren Subject: Re: device tree / how to build/compile & use with u-boot to boot uImage? Message-ID: <20070209224142.GC7339@localhost.localdomain> References: <45CCF4EF.9050507@smiths-aerospace.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <45CCF4EF.9050507@smiths-aerospace.com> Cc: linuxppc-dev@ozlabs.org, linuxppc-embedded@ozlabs.org, "Morrison, Tom" List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Fri, Feb 09, 2007 at 05:25:51PM -0500, Jerry Van Baren wrote: > Morrison, Tom wrote: > > All, > > > > Sorry for my ignorance here, but we have upgraded our kernel from > > 2.6.11.xx to 2.6.20-rcx (using a specific git-branch for the mpc85xx) > > to run on the MPC8548CDS eval board (using default options provided > > by this branch for this eval board). I successfully compiled/loaded the > > uImage, but it hangs after decompression (with root=/dev/nfs) > > > > Also, I was told to upgrade our u-boot source code (with another git > > branch for to the mpc85xx) and successfully get to the u-boot prompt. > > > > From googling through the lists - it seems that I need to build a > > device tree blob and pass that device tree to the kernel in some > > fashion? > > > > I tried to compile the default dts image (using the dtc compiler > > installed by LTIB), but it is complaining about no '/chosen' in > > the definition: > > > > /dtc -I dts -O dtb - -o mpc8548cds.dtb -V 16 dts/mpc8548cds.dts > > Trivia: the no "/chosen" warning can be ignored. The u-boot command > "bootm" generates the "/chosen" branch when you run the command and it > boots linux. > > Note: You want version 16 (or better?) for the fdt blob. I believe the > dtc defaults to this now, but it wasn't always that way. Actually you want version 17 - just as soon as I get around to implementing that in dtc. v16 and v17 have no differences that the kernel looks at though, so it doesn't really matter. -- David Gibson | I'll have my music baroque, and my code david AT gibson.dropbear.id.au | minimalist, thank you. NOT _the_ _other_ | _way_ _around_! http://www.ozlabs.org/~dgibson