From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from bali.collaboradmins.com (bali.collaboradmins.com [148.251.105.195]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 81F3525EF9C for ; Wed, 14 May 2025 09:58:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=148.251.105.195 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747216689; cv=none; b=W/PLtEDcpiUcua2+DZzke+NcsE+QSaixf2jX7cE/6ppqYEkM7urj4LGsNLcCNlWp+lAE7/3F0XOAuFwkqMHzeOHa5koQJSqe0JipsI7inR1Ftkcm+/hGbLO8H4RnMCGv2m7WQ+CRUgrZGG+AJarfz0vxIwucWUhWvunTbg3Gb7U= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1747216689; c=relaxed/simple; bh=8qzF0dnibpzSwk28HHXwMXKVCE2C0IRgQqjSRLDXxF4=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=I0uFrAdL2YWEEHO4JRFoJJRcAMZxD5ZVfMDZlDciD6quVJIYM8dqRu1OyonPfK+hgO9uFnavvOjE4+wj5w65e7GnPQBBGYFD50GvsTptE7WQStjs/noYHm8wxVZ0Jjnp4stmTCfBTC+DmZnSb1kFPXMO3DTt2vX+iW3YtKGMPI8= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com; spf=pass smtp.mailfrom=collabora.com; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b=hP94fQbW; arc=none smtp.client-ip=148.251.105.195 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=collabora.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=collabora.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=collabora.com header.i=@collabora.com header.b="hP94fQbW" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=collabora.com; s=mail; t=1747216680; bh=8qzF0dnibpzSwk28HHXwMXKVCE2C0IRgQqjSRLDXxF4=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=hP94fQbWKz+uhHQTs97vAzBtt43GNsf3+oV5qJLFjImHMUcnAeII1j72Jav5HgM9W VogXJD/dblDIFTonYJh+gA0jY+6ozilq60FrDX9PoRoY1c/GNPKEJaUCwzBO7PJTHI IZuZPC16pSZvijRdp5G/9Tz+Q9+ZssJ9Mw9IwgERok5Mp66Yna3oPlZC8acOJNNAlx nSmTuWV3fE3VXaxK74TjedgXI5eT7u53uFVsX/IWF/+QOgRKz+X4uAHwuzq5YBtk7i jS/JROnuzjbwRLpwUbG2sQDHuX0aNDrLiJLjm5gpBcx+3jlP5XXPtGaf+HofiMgQ4f yGB9VfG6WFl+w== Received: from [192.168.50.250] (unknown [171.76.80.110]) (using TLSv1.3 with cipher TLS_AES_128_GCM_SHA256 (128/128 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits)) (No client certificate requested) (Authenticated sender: vignesh) by bali.collaboradmins.com (Postfix) with ESMTPSA id 010DD17E153D; Wed, 14 May 2025 11:57:57 +0200 (CEST) Message-ID: <6c187b50-8ac0-42ac-af46-5357a26cb830@collabora.com> Date: Wed, 14 May 2025 15:27:55 +0530 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: x86: Boot failure on select chromebooks with v6.15-rc5 To: dmkhn@proton.me Cc: Ingo Molnar , dmukhin@ford.com, mingo@redhat.com, andriy.shevchenko@linux.intel.com, x86@kernel.org, daniels , Daniel Stone , robdclark , lumag@kernel.org, linux-kernel References: <45450eeb-1866-4bf6-a83b-1f28e26f311c@collabora.com> Content-Language: en-US From: Vignesh Raman In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Hi Denis On 12/05/25 23:00, dmkhn@proton.me wrote: > Hi, > > On Fri, May 09, 2025 at 01:07:54PM +0530, Vignesh Raman wrote: >> Hi Ingo, >> >> On 09/05/25 12:07, Ingo Molnar wrote: >>> >>> * Vignesh Raman wrote: >>> >>>>> What boot cmdline does your kernel have? The MMIO-UART patches should >>>>> only have an effect if the feature is specifically enabled via a boot >>>>> option: >>>>> >>>>> + if (!strncmp(buf, "mmio32", 6)) { >>>>> + buf += 6; >>>>> + early_mmio_serial_init(buf); >>>>> + early_console_register(&early_serial_console, keep); >>>>> + buf += 4; >>>>> + } >>>>> >>>> >>>> amdgpu:stoney: >>>> earlyprintk=uart8250,mmio32,0xfedc6000,115200n8 console=ttyS0,115200n8 >>>> root=/dev/nfs rw nfsroot=192.168.201.1:/var/lib/lava/dispatcher/tmp/18598802/extract-nfsrootfs-wgn1xjer,tcp,hard,v3 >>>> init=/init rootwait usbcore.quirks=0bda:8153:k ip=dhcp >>>> tftpserverip=192.168.201.1 >>>> >>>> i915:amly: >>>> earlyprintk=uart8250,mmio32,0xde000000,115200n8 console=ttyS0,115200n8 >>>> root=/dev/nfs rw nfsroot=192.168.201.1:/var/lib/lava/dispatcher/tmp/18598804/extract-nfsrootfs-5rlm_b6z,tcp,hard,v3 >>>> init=/init rootwait usbcore.quirks=0bda:8153:k ip=dhcp >>>> tftpserverip=192.168.201.1 >>>> >>>> i915:whl: >>>> earlyprintk=uart8250,mmio32,0xde000000,115200n8 console=ttyS0,115200n8 >>>> root=/dev/nfs rw nfsroot=192.168.201.1:/var/lib/lava/dispatcher/tmp/18598833/extract-nfsrootfs-3w0w5_mi,tcp,hard,v3 >>>> init=/init rootwait usbcore.quirks=0bda:8153:k ip=dhcp >>>> tftpserverip=192.168.201.1 >>> >>> Well, if you remove the earlyprintk option then it will boot fine, >>> right? >> >> Yes, it works when mmio32 option is removed. >> >> https://gitlab.freedesktop.org/vigneshraman/linux/-/jobs/76005338 >> >> earlyprintk=uart8250,0xde000000,115200n8 console=ttyS0,115200n8 >> root=/dev/nfs rw nfsroot=192.168.201.1:/var/lib/lava/dispatcher/tmp/18599938/extract-nfsrootfs-neuejjq0,tcp,hard,v3 >> init=/init rootwait usbcore.quirks=0bda:8153:k ip=dhcp >> tftpserverip=192.168.201.1 > > For the above example, can you please try something like > > earlyprintk=mmio32,0xde000000,nocfg > > ? This option didn’t work. For now, we’ll use earlycon instead of earlyprintk to fix the issue. Thanks. Regards, Vignesh > > In my case, configuring exact baud rate did not work. I started to dig that, > but did not finish, because `nocfg` worked (firmware happened to configure the > UART correctly). Using `nocfg` was sufficient for the system bringup debugging. > >> >>> >>> The earlyprintk=mmio32 in v6.15 is a new debugging feature that was >>> tested on a single board by Denis Mukhin AFAIK, and it may or may not >>> work on your particular UART - even assuming that all the parameters >>> are correct. > > Correct, I have tested with one board only and with limited UART configuration > combinations. > >> >> So the earlyprintk=mmio32 debugging feature is needed only for v6.15 and is >> not necessary in previous kernels (e.g., v6.14 and earlier). Is my >> understanding correct? >> >> Regards, >> Vignesh >> >>> >>> Thanks, >>> >>> Ingo >> > > Thanks, > Denis >