From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from wa-out-1112.google.com (wa-out-1112.google.com [209.85.146.179]) by ozlabs.org (Postfix) with ESMTP id 315D5DDDFC for ; Thu, 27 Dec 2007 13:55:54 +1100 (EST) Received: by wa-out-1112.google.com with SMTP id m28so4656742wag.13 for ; Wed, 26 Dec 2007 18:55:52 -0800 (PST) Message-ID: <9e4733910712261855p74a64c48pc7e89ebdd97d4a76@mail.gmail.com> Date: Wed, 26 Dec 2007 21:55:51 -0500 From: "Jon Smirl" To: "Siva Prasad" Subject: Re: Device node - How does kernel know about it In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 References: 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: , On 12/26/07, Siva Prasad wrote: > Hi, > > I am really interested in finding out how kernel knows about device > nodes and how the whole thing work. This is as part of my debugging > effort on 8641D based PowerPC board. > > * It all started with the problem of "not printing" any thing that comes > from ramdisk (echo and printf statements), while kernel printk's work > perfectly fine. > * Ramdisk is also executing fine, just that prints are not coming out of > serial. I can see the execution of various user programs with a printk > in sys_execve() routine. Ramdisk has all the required files like > /dev/console, /dev/ttyS0, etc. Does adding console=ttyS0,baud to the kernel boot command line fix it? -- Jon Smirl jonsmirl@gmail.com