Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756264Ab1EWQa3 (ORCPT ); Mon, 23 May 2011 12:30:29 -0400 Received: from smtp-out.google.com ([216.239.44.51]:39832 "EHLO smtp-out.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755526Ab1EWQa2 convert rfc822-to-8bit (ORCPT ); Mon, 23 May 2011 12:30:28 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=google.com; s=beta; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :cc:content-type:content-transfer-encoding; b=AGtXurghLt76vf6nCJdrLmQFeknPRNJVvAczAqjuAUGz6dMG6Ph767qImJW0LyUFZQ /k9KQMT74jndTZF4WQ4g== MIME-Version: 1.0 In-Reply-To: References: <334319B2EBE0B144BAE1402B79D82DC5CE13B056@srvpegasus> <334319B2EBE0B144BAE1402B79D82DC5CE13B05A@srvpegasus> From: Bjorn Helgaas Date: Mon, 23 May 2011 10:29:55 -0600 Message-ID: Subject: Re: Kernel > 2.6.30: PCI issue causes Kernel freeze at booting To: "Hornung, Michael" Cc: "linux-kernel@vger.kernel.org" , "linux-pci@vger.kernel.org" Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8BIT X-System-Of-Record: true Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1482 Lines: 33 On Wed, May 18, 2011 at 7:56 AM, Bjorn Helgaas wrote: > On Wed, May 18, 2011 at 1:44 AM, Hornung, Michael wrote: >>>> There is an UART (FPGA IP Core) in that system located at address 1900h using interrupt 3. In order to get Kernel messages at boot time, >>>> I changed file arch/x86/include/asm/serial.h as follows: >>>> >>>> - ? ? ? ?{ 0, BASE_BAUD, 0x3F8, 4, STD_COM_FLAGS }, ? ? ?/* ttyS0 */ ? ? \ >>>> + ? ? ? ?{ 0, BASE_BAUD, 0x1900, 3, STD_COM_FLAGS }, ? ? /* ttyS0 */ ? ?\ >>>> >>>> that is the only change I made to the kernel sources. >> >>> Is this UART connected via PCI? ?I don't think so, because I don't see >>> any I/O BARs that include 0x1900. >> >> The UART is connected via LPC bus. > > Makes sense; that's a common way for attaching UARTs, and they are > normally described via ACPI. ?When you do that, I think it will show > up as ttyS4 (be sure you build with CONFIG_SERIAL_8250_PNP=y), so > you'll have to use "console=ttyS4" when you boot. ?ttyS0-ttyS3 are > taken by the hard-coded ports in serial.h, even though they may not > exist on your platform. Hi Michael, Any update on this problem? Did it make any difference to put the UART in the ACPI namespace? Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/