From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail.chez-thomas.org (hermes.mlbassoc.com [76.76.67.137]) by ozlabs.org (Postfix) with ESMTP id F066DDDE1B for ; Wed, 1 Apr 2009 07:45:22 +1100 (EST) Message-ID: <49D280E0.9020701@mlbassoc.com> Date: Tue, 31 Mar 2009 14:45:20 -0600 From: Gary Thomas MIME-Version: 1.0 To: "Matthew L. Creech" Subject: Re: MPC83xx console : no output after handover References: <5ee96a840903311330y36ed97bet92319da8d118086@mail.gmail.com> In-Reply-To: <5ee96a840903311330y36ed97bet92319da8d118086@mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1 Cc: linuxppc-dev@ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Matthew L. Creech wrote: > (Sorry if this is a dupe, but I think my first attempt was filtered out) Nope, it made it. > Hi, > > I'm trying to get Linux booting on a custom board based on the MPC8313 > ERDB, but there's no output after the console is transferred. I get > the following: > > Using MPC831x RDB machine description > Linux version 2.6.29 (mlcreech@lap) (gcc version 4.3.2 (Sourcery G++ Lite 4.3-50 > ) ) #2 PREEMPT Tue Mar 31 14:54:27 EDT 2009 > console [udbg0] enabled > > ... (normal boot output) ... > > Serial: 8250/16550 driver, 4 ports, IRQ sharing disabled > serial8250.0: ttyS0 at MMIO 0xe0004500 (irq = 16) is a 16550A > console handover: boot [udbg0] -> real [ttyS0] > serial8250.0: ttyS1 at MMIO 0xe0004600 (irq = 17) is a 16550A > > If I boot with "console=udbg0,115200", then it gets much further along > before printing "turn off boot console udbg0". So presumably the > kernel is booting beyond this point, but my console isn't printing any > output. I traced from that last line back up the call stack to the > end of drivers/serial/8250.c:serial8250_init(), and everything seems > okay (it returns 0, and pritnk() still works fine at that point). I'm > not sure where to go from there to figure out where the problem lies. > Could someone point me in the right direction, or suggest what might > cause a console problem like this? What does your command line (boot args) when it fails? It should probably have something like "console=ttyS0,115200" in it. -- ------------------------------------------------------------ Gary Thomas | Consulting for the MLB Associates | Embedded world ------------------------------------------------------------