From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3A9E0C761A6 for ; Tue, 4 Apr 2023 12:03:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234152AbjDDMDB (ORCPT ); Tue, 4 Apr 2023 08:03:01 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:44120 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234625AbjDDMC6 (ORCPT ); Tue, 4 Apr 2023 08:02:58 -0400 Received: from vps.xff.cz (vps.xff.cz [195.181.215.36]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 618902D42; Tue, 4 Apr 2023 05:02:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=xff.cz; s=mail; t=1680609751; bh=uVAMkMqMikWXIauVjMve6Gn4H0bTde07iBs06xjAvnU=; h=Date:From:To:Cc:Subject:X-My-GPG-KeyId:References:From; b=0V074kW0++4v6ZNG2SqAZq7Z8PMfa8C6VJ8LSKbJWbRmQQNxQYsyRmrn3pqvdlWMR v1U+SBhm+EfQt+sK9kwqvL6ocBi+02SSFW4IVDeQ3GYJtfY3YbYpFVcYA/H50DgSKq jCLK/DFpFXaSuYmoN+lexTBMB8Y8wKNXSrIfFP10= Date: Tue, 4 Apr 2023 14:02:31 +0200 From: =?utf-8?Q?Ond=C5=99ej?= Jirman To: Javier Martinez Canillas Cc: Martijn Braam , Heiko =?utf-8?Q?St=C3=BCbner?= , linux-kernel@vger.kernel.org, Peter Robinson , Caleb Connolly , Jarrah Gosbell , Krzysztof Kozlowski , Rob Herring , Tom Fitzhenry , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org Subject: Re: [PATCH] arm64: dts: rockchip: Change serial baud rate for Pinephone Pro to 1.5 MB Message-ID: <20230404120231.2enpesad2lhde6sb@core> Mail-Followup-To: =?utf-8?Q?Ond=C5=99ej?= Jirman , Javier Martinez Canillas , Martijn Braam , Heiko =?utf-8?Q?St=C3=BCbner?= , linux-kernel@vger.kernel.org, Peter Robinson , Caleb Connolly , Jarrah Gosbell , Krzysztof Kozlowski , Rob Herring , Tom Fitzhenry , devicetree@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-rockchip@lists.infradead.org X-My-GPG-KeyId: EBFBDDE11FB918D44D1F56C1F9F0A873BE9777ED References: <20230403175937.2842085-1-javierm@redhat.com> <3738011.44csPzL39Z@diego> <52d83a29-0f16-cd4c-9810-7c6bd497fe85@brixit.nl> <87ttxvdgb7.fsf@minerva.mail-host-address-is-not-set> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <87ttxvdgb7.fsf@minerva.mail-host-address-is-not-set> Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org Hello, On Tue, Apr 04, 2023 at 01:42:36PM +0200, Javier Martinez Canillas wrote: > Martijn Braam writes: > > > On 4/4/23 09:51, Heiko Stübner wrote: > >> Hi, > >> > >> Am Montag, 3. April 2023, 19:59:37 CEST schrieb Javier Martinez Canillas: > >>> This baud rate is set for the device by mainline u-boot and is also what > >>> is set in the Pinebook Pro Device Tree, which is a device similar to the > >>> PinePhone Pro but with a different form factor. > >>> > >>> Otherwise, the baud rate of the firmware and Linux don't match by default > >>> and a 'console=ttyS2,1500000n8' kernel command line parameter is required > >>> to have proper output for both. > >> The interesting question is always if this will break someone else's setup. > >> I've never really understood the strange setting of 1.5MBps, but on the > >> other hand it _is_ a reality on most boards. > > > > It breaks my device test setup at least. The extra speed isn't worth the > > hassle > > More than the extra speed is to have consistency accross all the rockchip > devices in upstream and also sync with mainline u-boot. > > > of having a few devices at weird baudrates and the bootloader already > > starts outputting debug logs at 115200 baud. > > > > And mine starts outputting at 1.5MBps :) I guess that there isn't a one > size fits all, so the question is whether the bikeshed color is what was > painted in all other rockchip boards or the one that Tow-Boot has chosen. For what it's worth, levinboot also defaults to 1.5 Mbaud. https://gitlab.com/DeltaGem/levinboot/-/blob/release/rk3399/entry.S#L65 https://gitlab.com/DeltaGem/levinboot/-/blob/release/configure.py#L67 And it's very nice anything above >115200 is not broken by bad HW design, like on original Pinephone, so this higher speed actually works. ;) kind regards, o. > -- > Best regards, > > Javier Martinez Canillas > Core Platforms > Red Hat >