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 X-Spam-Level: X-Spam-Status: No, score=-9.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7607FC433E1 for ; Wed, 22 Jul 2020 15:48:00 +0000 (UTC) Received: from merlin.infradead.org (merlin.infradead.org [205.233.59.134]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 411F52065F for ; Wed, 22 Jul 2020 15:48:00 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="kDrGyQAf" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 411F52065F Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.de Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=merlin.20170209; h=Sender:Content-Transfer-Encoding: Content-Type:Cc:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To:Date:To:From: Subject:Message-ID:Reply-To:Content-ID:Content-Description:Resent-Date: Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=qHcQ/5dhz8V1carXp/ddstMV2wAMk3C5lQyL6cL9VBs=; b=kDrGyQAfiifU60Cxcr8OOclaa bQWQCmXuD12bg6LhWMFOlX/uE8qPFByRKuM2+qr8eLrd0ikYNVBRgoVE6QC10U6cVtge0KYYtGbsd rxd2kZ72L2P993BCFmvpK5EGI5e7wwVlj9OUu/3WXPjf0i4mQ/bwnO16eVQ1SuuEnnIDUFqBV3Q8b cF3x/+MDE1jTZTvf+SlrxzYWsScOmeCwsy94qGVG8QjQsbn+uQw4fogyKPhy1oTkm30SUOc5aJwcv ErbhB2ZQDw//iqhXiDAhDbsEwyqKbhTyMWhKjgDrg4r77aR/vuYikP83EjZgiUrubXujA5B4YE8HK yN+tlrVnQ==; Received: from localhost ([::1] helo=merlin.infradead.org) by merlin.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1jyGwt-0001iC-7E; Wed, 22 Jul 2020 15:46:27 +0000 Received: from mx2.suse.de ([195.135.220.15]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1jyGwq-0001hb-Mu; Wed, 22 Jul 2020 15:46:25 +0000 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id B5431AC83; Wed, 22 Jul 2020 15:46:30 +0000 (UTC) Message-ID: Subject: Re: Issues attempting to use Raspberry Pi 4 serial console on mainline From: Nicolas Saenz Julienne To: Peter Robinson , Nathan Chancellor Date: Wed, 22 Jul 2020 17:46:22 +0200 In-Reply-To: References: <20200721225724.GA1005852@ubuntu-n2-xlarge-x86> <63244277a1c8989f87906746742141eba01d8bb5.camel@suse.de> User-Agent: Evolution 3.36.3-0ubuntu1 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20200722_114624_849363_362DFC9F X-CRM114-Status: GOOD ( 22.37 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: clang-built-linux@googlegroups.com, bcm-kernel-feedback-list@broadcom.com, linux-rpi-kernel@lists.infradead.org, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Nathan, Peter, On Wed, 2020-07-22 at 15:41 +0100, Peter Robinson wrote: [...] > On Wed, Jul 22, 2020 at 2:27 PM Nicolas Saenz Julienne > > For reference I just booted linux-next with this setup: > > > > boot partition: > > ...Latest firmware files taken from the RPi firmware repo [1]... Natan, it seems I lied here and been using an outdated firmware version. I've just validated what Peter comments below, and the last working firmware release with this setup is Feb12[1]. Given your use case I'd just use that and forget about it. > > Image #Copied from linux build > > bcm2711-rpi-4-b.dtb #Copied from linux build > > config.txt > > cmdline.txt > > > > config.txt: > > kernel=Image > > enable_uart=1 > > arm_64bit=1 > > > > cmdline.txt: > > console=tty console=ttyS1,115200 text root=/dev/nfs > > nfsroot=10.42.0.1:/home/nico/netboot/root,vers=3 rw ip=dhcp > > rootwait > > elevator=deadline > > [...] > > > > The issue with the mini UART is its clock, which is derived from VPU's, which > > is itself controlled by RPi's firmware. Changes might happen behind the > > kernel's back, and the mini UART divisors will not be updated accordingly. > > This is an area the we could do better, but no one found a good solution yet. > > That said, for now, when using the upstream kernel, VPU's clock should be > > stable as we forbid the firmware from performing frequency scaling on that > > clock. > > There has actually been a regression in the firmware here, prior to > mid April if the enable_uart=1 I always had clean output on the serial > console, since that date on the rpi3/3b+/4 I get a whole bunch of > junk, revert to an older firmware (I've been using April 1st ) and it > all goes back to being fine. I've not had time to actually report it > yet, and it's still a problem with the latest firmware but a quick > look it likes similar to this issue reported in late April: > > https://github.com/raspberrypi/firmware/issues/1376 Thanks for pointing it out! I missed that bug report. I'll try to get the gist of it. Regards, Nicolas [1] https://github.com/raspberrypi/firmware/releases _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel