From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754162AbcAMQeP (ORCPT ); Wed, 13 Jan 2016 11:34:15 -0500 Received: from mail-pf0-f172.google.com ([209.85.192.172]:34587 "EHLO mail-pf0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753065AbcAMQeK (ORCPT ); Wed, 13 Jan 2016 11:34:10 -0500 Subject: Re: [RFC PATCH] always probe UART HW when options are not specified To: Sebastian Frias References: <5672D18E.8000301@laposte.net> <5672E2CF.6080705@hurleysoftware.com> <5672E76A.3010506@laposte.net> <5672F588.8070503@hurleysoftware.com> <5672FD35.5070609@laposte.net> <56731689.70702@hurleysoftware.com> <56740FC3.50302@laposte.net> <5674204C.1000907@hurleysoftware.com> <56782DE5.7090708@laposte.net> <56798EC7.1030804@laposte.net> <5693C52B.90003@laposte.net> <5693D41E.8050601@hurleysoftware.com> <5693ECBA.50003@laposte.net> <5693FD3C.5080601@hurleysoftware.com> <5694C94B.3090405@free.fr> <56950C21.3010805@laposte.net> <5695584E.3040902@hurleysoftware.com> <5696317C.4020709@laposte.net> Cc: Mason , Greg Kroah-Hartman , linux-serial@vger.kernel.org, LKML , Mans Rullgard From: Peter Hurley Message-ID: <56967C7F.4060705@hurleysoftware.com> Date: Wed, 13 Jan 2016 08:34:07 -0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.4.0 MIME-Version: 1.0 In-Reply-To: <5696317C.4020709@laposte.net> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 01/13/2016 03:14 AM, Sebastian Frias wrote: > Hi Peter, > > On 01/12/2016 08:47 PM, Peter Hurley wrote: >> On 01/12/2016 06:22 AM, Sebastian Frias wrote: >>> >>> For the record, I'm using a SoC emulator, and thus do not have a bootloader per se and there are a bunch of other things that I cannot count on. >>> The emulator has the UART pre-setup, so I just need Linux to take over without changing the parameters. >>> Ideally, I would like to have the same image of Linux+DT to start in any instance of the emulator or real chips, regardless of the clock ratios, that's why I sort of need Linux to not change the UART speed, which is quite tricky because there are no clock generators in the emulator. >> >> Got it, thanks for the info. >> Please test the series I just cc'd you on plus the patch I sent >> you yesterday. >> >> That should get you an earlycon up and running on that simulator; >> let me know if it doesn't and we'll go from there. > > Ok, thanks. > I will try as soon as we finish rebasing our changes on top of > "mainline" (or HEAD, or is it "-next"? I don't know how you guys call > the most recent code base for Linux) The basic tree organization is Linus's tree <---- linux-next[date] <----- maintainers' trees (mainline) (next) (eg., Greg's tty tree) The patches I sent you (along with any required modifications during the review cycle) are based on the tty-next branch in Greg's tty tree here git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git As of this email, Greg's tree is based on Linus's 4.4-rc6 which should be stable enough for you to test these patches on. > Actually, I tried yesterday on a 4.1.13 but > "[drivers/tty/serial/earlycon.c:62] earlycon_map()" was still the > last message I got, just as with the OF_EARLYCON_DECLARE hack I had > previously talk about, and so I would like to test on the same > conditions than you, mainline. So just to confirm, you applied "8250: Add Au1x00/RT288x earlycon support" to 4.1.13 and the earlycon didn't come up when you used the kernel command line option like so: earlycon=rt288x,mmio32,0x10700 Is that correct?