From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) (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 606191D63D1 for ; Tue, 17 Dec 2024 14:46:19 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.133.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734446781; cv=none; b=PUA69RF4mce/z4ctqCY4uexZB9btRXhxU3MWNyc3e2zcc1wXo+lHwxSPsT1euVZx4j8Ruz5ztZud7SahC+vOyJvFtZK34QfPDa1aftsPIbVwTnZh+vQl5hbgvcUJuzhsli+2OY0GeJwt5wtBb4XSpASOM0lxQZbZR+F0ixNEyR0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734446781; c=relaxed/simple; bh=ZYWFGeyXQ1mkGQsqFz5HmlmiGpfux1ORE5YnV17FwwU=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=nB6tmRYxG0cuCKWCYBOaqBDlZcGByke3C4xydVTPXwqA8Hgew1nIY8bUJSZUasSgOTA0MH3jh8AV/X5KTsgJXPgX9sdgVlHh+W67FRwPSiPp53H0BH6a28ctxXd8210mCIF2i9Vjr7Ar7qsrZrL8qXr3Qywd7ublYIhvC5gAE/I= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=OGHFRiok; arc=none smtp.client-ip=170.10.133.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="OGHFRiok" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1734446778; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=eDQnbhzbULoS+W3TBQiABSNsadwzS0IORV98NaKZMJE=; b=OGHFRioksUlAOlyMz9wLZ0Ljd0Jie9PiY/TJuixKCB5NvCm4OsLF2XxJK0nibI0/Fidrsd 5yXgZi+MGJueWD480I6k0sk4SXDpV9EPbFHtvmbOkU35R/Hx0BgJSM966a3KpBxzQaiVKP 2dgkkkiF983NUk/mcbZP04AXA0PI9nY= Received: from mail-wm1-f72.google.com (mail-wm1-f72.google.com [209.85.128.72]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-402-evSQBWpPNBqSOgq-auqTJA-1; Tue, 17 Dec 2024 09:46:17 -0500 X-MC-Unique: evSQBWpPNBqSOgq-auqTJA-1 X-Mimecast-MFC-AGG-ID: evSQBWpPNBqSOgq-auqTJA Received: by mail-wm1-f72.google.com with SMTP id 5b1f17b1804b1-43619b135bcso30131635e9.1 for ; Tue, 17 Dec 2024 06:46:16 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1734446775; x=1735051575; h=content-transfer-encoding:in-reply-to:from:content-language :references:cc:to:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=eDQnbhzbULoS+W3TBQiABSNsadwzS0IORV98NaKZMJE=; b=YL00r2otp1Um/Ky528zQS1arSR++fn8fUy/YKB990//hwXnWODPdY/M7UM5Tqd8nm3 Clf5Qf9eaVWWm5m3r1B1GMf5Ko7JsabvO7xJAGmmTetbbZI1Kd+3iAloZQarBKpXcGUg 27Reqrp9wCmckpjdFFcResF/sXkmtSxURZEsbYvXK3ILbUxwRt+ZXMkI4MrsJoHtX0Wj DQwCHFik49eVA3E8M2nnlrm5zxzzUk3arShwPELnIAXbE/dbVQjVRlbLqdPXc1ioiPxz A9RgRcYNsZiGIzGfFqbdQOLLavDHIVSB+H40Vo6J+eSkviow8E36sckCOHtUN3LHYsQR 9dqg== X-Forwarded-Encrypted: i=1; AJvYcCVn3ittxIh0R5pXUHcMdzVxpig6+pJ8ZclA10qP5W9AL71nznjHROSM9/F9H22L7PADYOme1kLjHOeKZTQ6fC96jw==@vger.kernel.org X-Gm-Message-State: AOJu0YxKxcUayljAYqBqNzxKmq0RyofNYJoDMpME9ErRXwAW43ske55f yARGiqhOBvXCZo5drI0SXTt+sxvyUwdw6mJv+ZowIMdu8rIoBsNk9drCmjEkJJBZ49aOEBVGpb2 Gp1Zao8GEBHThrydkZJqvhHpioUNx0sptLl6DidhPehOEfhEvlG6PCiWTft4xrlN2GMJ5 X-Gm-Gg: ASbGncuLD5iqHj+GLwlvNA7CIqGF9sqeV1O8T3KcDBy+UDrv2wNiTqT9zZr4BeHRWWy 3YgHyhxn7nYLypqPLhXkyUDM59n2daXre+xs25KvWK9BO/wFla+FIJCh0cerca6vW/03ff3nqKU MmEKWZDnSprAEz2YVZdtp56LG6avDa7mFG0crGw01qDv5Anir+VGV7UVHZrZVbtcqsxg+uyh/+H GySVe8I4r20aVbVNJstrnMNJYtps6hngR9Zq8BpETBuudVWkFl9swPoSGVbI6VBLwQv6KEaSSOD TD5wB+Q9KJiFsgsSWEiw X-Received: by 2002:a05:600c:4e88:b0:434:a929:42bb with SMTP id 5b1f17b1804b1-4364769b321mr39642385e9.18.1734446775067; Tue, 17 Dec 2024 06:46:15 -0800 (PST) X-Google-Smtp-Source: AGHT+IEb7FOvU3aK3NlCVSo7lhvRfjnfY6sZdz6YbmqcryV9O2xsfMlBv61Xb0L2X14JUy9wFlLD9Q== X-Received: by 2002:a05:600c:4e88:b0:434:a929:42bb with SMTP id 5b1f17b1804b1-4364769b321mr39642125e9.18.1734446774667; Tue, 17 Dec 2024 06:46:14 -0800 (PST) Received: from ?IPV6:2a01:e0a:c:37e0:ced3:55bd:f454:e722? ([2a01:e0a:c:37e0:ced3:55bd:f454:e722]) by smtp.gmail.com with ESMTPSA id ffacd0b85a97d-388c8012249sm11244064f8f.10.2024.12.17.06.46.13 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Tue, 17 Dec 2024 06:46:14 -0800 (PST) Message-ID: <301714d8-0723-4881-83e8-24523c121bfe@redhat.com> Date: Tue, 17 Dec 2024 15:46:12 +0100 Precedence: bulk X-Mailing-List: linux-renesas-soc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v9 0/6] drm/log: Introduce a new boot logger to draw the kmsg on the screen To: Geert Uytterhoeven Cc: Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , David Airlie , Daniel Vetter , John Ogness , Javier Martinez Canillas , "Guilherme G . Piccoli" , bluescreen_avenger@verizon.net, Caleb Connolly , Petr Mladek , Jani Nikula , dri-devel@lists.freedesktop.org, linux-kernel@vger.kernel.org, Linux-Renesas References: <20241204160014.1171469-1-jfalempe@redhat.com> Content-Language: en-US, fr From: Jocelyn Falempe In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 17/12/2024 15:19, Geert Uytterhoeven wrote: > Hi Jocelyn, > > On Wed, Dec 4, 2024 at 6:41 PM Jocelyn Falempe wrote: >> drm_log is a simple logger that uses the drm_client API to print the kmsg boot log on the screen. >> This is not a full replacement to fbcon, as it will only print the kmsg. >> It will never handle user input, or a terminal because this is better done in userspace. >> >> If you're curious on how it looks like, I've put a small demo here: >> https://people.redhat.com/jfalempe/drm_log/drm_log_draft_boot_v2.mp4 >> >> Design decisions: >> * It uses the drm_client API, so it should work on all drm drivers from the start. >> * It doesn't scroll the message, that way it doesn't need to redraw the whole screen for each new message. >> It also means it doesn't have to keep drawn messages in memory, to redraw them when scrolling. >> * It uses the new non-blocking console API, so it should work well with PREEMPT_RT > > I gave this a try on Koelsch (R-Car M2-W), using rcar-du. > Unfortunately I don't see any kernel messages, and my monitor complains > about no signal. Does this require special support from the driver? It doesn't require a special support from the driver. But as it is the first drm client other than fbdev emulation, I'm not surprised it's broken on some driver. I know it works on virtio-gpu, nouveau, amdgpu, and even on a OnePlus 6 (Qualcomm SDM845/freedreno), without requiring driver changes. Do you have a serial console on this device, to check if there is something in kmsg? Best regards, -- Jocelyn > > CONFIG_DRM_CLIENT=y > CONFIG_DRM_CLIENT_LIB=y > CONFIG_DRM_CLIENT_SELECTION=y > CONFIG_DRM_CLIENT_SETUP=y > CONFIG_DRM_CLIENT_LOG=y > # CONFIG_DRM_CLIENT_DEFAULT_FBDEV is not set > CONFIG_DRM_CLIENT_DEFAULT_LOG=y > CONFIG_DRM_CLIENT_DEFAULT="log" > > Switching to fbdev gives a working display, as before: > > CONFIG_DRM_CLIENT_DEFAULT_FBDEV=y > # CONFIG_DRM_CLIENT_DEFAULT_LOG is not set > CONFIG_DRM_CLIENT_DEFAULT="fbdev" > > Thanks! > > Gr{oetje,eeting}s, > > Geert >