From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753379Ab0IVQy3 (ORCPT ); Wed, 22 Sep 2010 12:54:29 -0400 Received: from terminus.zytor.com ([198.137.202.10]:58788 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752828Ab0IVQy2 (ORCPT ); Wed, 22 Sep 2010 12:54:28 -0400 Message-ID: <4C9A3487.6080005@zytor.com> Date: Wed, 22 Sep 2010 09:53:27 -0700 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.7) Gecko/20100720 Fedora/3.1.1-1.fc13 Thunderbird/3.1.1 MIME-Version: 1.0 To: Bjorn Helgaas CC: mingo@redhat.com, linux-kernel@vger.kernel.org, yinghai@kernel.org, just.for.lkml@googlemail.com, tglx@linutronix.de, hpa@linux.intel.com, Feng Tang , Alan Cox , greg@kroah.com Subject: Re: Early console confusion References: <4C7B0578.8090807@kernel.org> <201009220912.45360.bjorn.helgaas@hp.com> <4C9A271F.30608@zytor.com> <201009221044.58735.bjorn.helgaas@hp.com> In-Reply-To: <201009221044.58735.bjorn.helgaas@hp.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 09/22/2010 09:44 AM, Bjorn Helgaas wrote: > > If we don't like "uart8250,io,0x3f8" (which I agree is awfully clunky), > we could easily add something like "console=com1" which encapsulated > the well-defined PC concept. console=ttyS0 ... already works fine. > It would be similar to "earlyprintk=ttyS0", > and if it could be made *enough* like it, maybe "earlyprintk=ttyS0" > could be dropped. > > I also see the recent "earlyprintk=hsu" patch from Feng Tang, and I > wonder whether that could be recast in the "console=hsu" style. Like > "com1", "hsu" is apparently enough to specifically identify a device. > > I think it's nicer to extend "console=" in ways that allow early > devices, because then users don't have to mess with both "console=" > and "earlyprintk=". The 8250_early driver has a reasonable model > of switching from the early device to the real one automatically, > so maybe something like this is all we would need: console= is supported multiple times, and enabling console= shouldn't necessarily enable earlyprintk... But yes, it's ugly and we have bass-ackwards compatibility problem... -hpa