From owner-freebsd-arm@FreeBSD.ORG Sat Mar 1 15:49:11 2014 Return-Path: Delivered-To: freebsd-arm@FreeBSD.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id 22400BBE for ; Sat, 1 Mar 2014 15:49:11 +0000 (UTC) Received: from mho-02-ewr.mailhop.org (mho-02-ewr.mailhop.org [204.13.248.72]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.freebsd.org (Postfix) with ESMTPS id E8FB315AF for ; Sat, 1 Mar 2014 15:49:10 +0000 (UTC) Received: from c-24-8-230-52.hsd1.co.comcast.net ([24.8.230.52] helo=damnhippie.dyndns.org) by mho-02-ewr.mailhop.org with esmtpsa (TLSv1:AES256-SHA:256) (Exim 4.72) (envelope-from ) id 1WJmA1-0006wk-M5; Sat, 01 Mar 2014 15:49:09 +0000 Received: from [172.22.42.240] (revolution.hippie.lan [172.22.42.240]) by damnhippie.dyndns.org (8.14.3/8.14.3) with ESMTP id s21Fn5C3044409; Sat, 1 Mar 2014 08:49:05 -0700 (MST) (envelope-from ian@FreeBSD.org) X-Mail-Handler: Dyn Standard SMTP by Dyn X-Originating-IP: 24.8.230.52 X-Report-Abuse-To: abuse@dyndns.com (see http://www.dyndns.com/services/sendlabs/outbound_abuse.html for abuse reporting information) X-MHO-User: U2FsdGVkX182teorEwndFq5wms4dPJe8 Subject: Re: A unified imx6 kernel config, old WANDBOARD-* configs going away From: Ian Lepore To: Tim Kientzle In-Reply-To: References: <1393594966.1149.161.camel@revolution.hippie.lan> Content-Type: text/plain; charset="us-ascii" Date: Sat, 01 Mar 2014 08:49:05 -0700 Message-ID: <1393688945.1149.225.camel@revolution.hippie.lan> Mime-Version: 1.0 X-Mailer: Evolution 2.32.1 FreeBSD GNOME Team Port Content-Transfer-Encoding: 7bit Cc: freebsd-arm X-BeenThere: freebsd-arm@freebsd.org X-Mailman-Version: 2.1.17 Precedence: list List-Id: "Porting FreeBSD to ARM processors." List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sat, 01 Mar 2014 15:49:11 -0000 On Sat, 2014-03-01 at 07:41 -0800, Tim Kientzle wrote: > On Feb 28, 2014, at 5:42 AM, Ian Lepore wrote: > > > I've added a new imx6 unified kernel config named IMX6. It has no > > compiled-in fdt, and can boot all three flavors of Wandboard when u-boot > > and ubldr load a dtb file. Folks should start using it and eventually > > the WANDBOARD* configs will go away when nobody needs them anymore. > > Nice! Another step towards GENERIC ARM. > > > the .dtb file in your /boot/kernel or /boot/modules directory, and ubldr > > will load it from there, using the filename set in the u-boot env var > > fdt_file. > > Using a U-Boot env var to specify the FDT is a nice idea. > > > Unfortunately we can't do a single image that boots any wandboard, > > because u-boot itself has to be different for each board. This is what > > my u-boot env looks like on each wandboard: > > > > => printenv > > baudrate=115200 > > bootcmd=run ubnet > > bootdelay=1 > > console=ttymxc0 > > fdt_file=wandboard-dual.dtb > > loadaddr=11000000 > > loaderdev=net > > ubmmc=fatload mmc 0 ${loadaddr} ubldr; bootelf > > ubnet=dhcp ${loadaddr} /wand/boot/ubldr;bootelf > > > > Environment size: 265/8188 bytes > > > > The only thing that differs per-board is the fdt_file setting, and the > > u-boot binary itself. > > If you could get to a single U-Boot binary, you might > be able to do what BeagleBone does: The U-boot.env > script detects the board variation and conditionally > loads the correct DTB blob. That's my long-term goal, but it'll take some major u-boot hacking, probably won't happen for months. The imx6 quad chip is different enough from the solo and dual-lite that a single u-boot to handle both will be kind of tricky the way the u-boot code is structured now. Doing a single u-boot for solo+dual-lite is so trivial I'm not sure why wandboard didn't do it that way. -- Ian