From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from AGRXSUSMAILB.smiths.aero (host241-chi.smiths-group.com [65.216.75.241]) by ozlabs.org (Postfix) with ESMTP id 19ED7DDEBF for ; Sat, 10 Feb 2007 09:25:53 +1100 (EST) Message-ID: <45CCF4EF.9050507@smiths-aerospace.com> Date: Fri, 09 Feb 2007 17:25:51 -0500 From: Jerry Van Baren MIME-Version: 1.0 To: "Morrison, Tom" Subject: Re: device tree / how to build/compile & use with u-boot to boot uImage? References: In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Cc: linuxppc-dev@ozlabs.org, linuxppc-embedded@ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , 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. [snip - others have chimed in] > Tom Morrison > Principal Software Engineer gvb