From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tony Lindgren Subject: Low level debugging using CONFIG_EARLY_PRINTK=y, omap-debug branch removed Date: Tue, 15 Dec 2009 16:53:38 -0800 Message-ID: <20091216005337.GR4575@atomide.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Return-path: Received: from mho-01-ewr.mailhop.org ([204.13.248.71]:49783 "EHLO mho-01-ewr.mailhop.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758238AbZLPAxl (ORCPT ); Tue, 15 Dec 2009 19:53:41 -0500 Received: from muru.com ([72.249.23.125] helo=localhost.localdomain) by mho-01-ewr.mailhop.org with esmtpa (Exim 4.68) (envelope-from ) id 1NKi96-0007iz-Fw for linux-omap@vger.kernel.org; Wed, 16 Dec 2009 00:53:40 +0000 Content-Disposition: inline Sender: linux-omap-owner@vger.kernel.org List-Id: linux-omap@vger.kernel.org To: linux-omap@vger.kernel.org Hi all, Recent commit 93fd03a8c6728b58879f8af20ffd55d9c32a778b added support for CONFIG_EARLY_PRINTK on ARM. Recent earlier kernels should work too by applying the patch in the commit above. This means we can now get rid of the old printk.c hack in the omap-debug branch, so I've deleted that branch. To use the earlyprintk, just do the following: 1. Make sure you have the necessary .config options set CONFIG_DEBUG_LL=y CONFIG_EARLY_PRINTK=y CONFIG_OMAP_LL_DEBUG_UART1=y # CONFIG_OMAP_LL_DEBUG_UART2 is not set # CONFIG_OMAP_LL_DEBUG_UART3 is not set The LL_DEBUG_UART above is typically 1, but it's 3 on Nokia boards. 2. Edit the kernel CMDLINE in your .config to have "debug earlyprintk" Optionally if you have a JTAG console, you can use CONFIG_DEBUG_ICEDCC instead LL_DEBUG_UART. I've also added these instructions to: http://www.elinux.org/Debugging_OMAP_kernel Regards, Tony