From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from fed1rmmtao09.cox.net (fed1rmmtao09.cox.net [68.230.241.30]) by ozlabs.org (Postfix) with ESMTP id 6C94D67A03 for ; Sat, 29 Apr 2006 05:52:03 +1000 (EST) Date: Fri, 28 Apr 2006 12:52:01 -0700 From: Tom Rini To: Kumar Gala Subject: Re: FT u-boot shim Message-ID: <20060428195201.GB458@smtp.west.cox.net> References: <4C61B597-BD91-4D05-BB40-43DE0319F123@kernel.crashing.org> <265F73F8-F641-4EDD-B88F-A2B2F7FA1308@kernel.crashing.org> <20060425182418.GA1132@gate.ebshome.net> <200604251329.35584.bcook@bpointsys.com> <248CD1B3-A33B-47F5-AFE8-F7C9DDCD1D0B@kernel.crashing.org> <20060425185314.GC1132@gate.ebshome.net> <1448E56E-1327-40D5-BE44-0DC103AC3E8A@kernel.crashing.org> <17489.64606.75404.314368@cargo.ozlabs.ibm.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: Cc: "linuxppc-dev@ozlabs.org list" , Paul Mackerras List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Fri, Apr 28, 2006 at 11:01:20AM -0500, Kumar Gala wrote: > However, I really hate introducing some third project that is > required. If we decide to pull ALL of boot wrappers out of the > kernel tree than I'd be ok with it. But until that time I think this > lives under arch/powerpc/boot/... The more I think about this, and hear about what some vendors do, pulling arch/p*pc/boot/ out of the kernel is making more and more sense. Especially with the serial headache, a depends-on-nothing, can-translate-$(firmware information) tool might be best. > What I envision as the way one boots for something like u-boot is one > of three options: > 1. using an old u-boot + boot wrapper (bd_t -> wrapper -> kernel) > 2. using a u-boot that is ft aware + dtb (boot command in u-boot > takes kernel & dtb images, updates blob and passes to kernel) > 3. using a u-boot that is ft aware + built in dtb. And more generally: 1. using an old firmware + kernel boot wrapper (firmware->dtb converter) boots kernel. 2. using a dtb-aware firmware boots kernel (compressed or not) and passes dtb in. > The issue is that for a given system/board you may need to support > multiple or all three. This raises the question where does the .dts > live. For the time being I say it lives in the boot wrapper part of > the kernel tree. Thus we handle the three cases as follows: We could stick it in the seprate kernel boot wrapper project. But I really think this really has to live in two places. The kernel should be The Owner, as until *BSD or something adopts this, it's a Linux-specific thing. But any firmware that wishes to skip the kernel boot wrapper and be a direct kernel booter, will need to own a copy. -- Tom Rini http://gate.crashing.org/~trini/