From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 ABBA03F8715; Fri, 26 Jun 2026 14:44:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782485044; cv=none; b=MTLhIqzQnu7Dk9ueaUV3tWgLaI7Ckc5uoh6RMHPvxZqByeihqn+fSlcWxrSPm8GtlIsbdKK48it8/W6HlRsCdAu1h+0aebA6MpB0VloVS2ohUe6y29bLAbzPmfz4C38CVGHesl45cqIIfvpbj+pM/bvE0TNMSUBoloMEYzANt8I= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1782485044; c=relaxed/simple; bh=t6+19co4wT+sR4HBKB1X6BEjvDKnU+F5CYbIIpRkYHo=; h=Message-ID:Date:MIME-Version:Subject:From:To:Cc:References: In-Reply-To:Content-Type; b=r2/rFjZjnPK6szMRAhe4hmwHrUkyyyKfsdDMljsuLTNCWXl75ohf+pxG/LMkcCoMIuZp727ZPxi2czeixI1emqcQhB0dqRX7r5XWMZXq3nMyI/97KcR/thkto3lWg32d9GijD/Ezvy1ac7bUfLQ7mpQnWP1YMmpbtF4w2/NCjKQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=MccSHJSg; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="MccSHJSg" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3153E1F000E9; Fri, 26 Jun 2026 14:44:01 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1782485043; bh=B4c6ILvGNvGsDJ3Rcq7xHv7I77cDvZeU88xDp65H8Ow=; h=Date:Subject:From:To:Cc:Reply-To:References:In-Reply-To; b=MccSHJSggSyVFtJWDvS/ObpLXL2icYa2/IsVO79CpZc0H6zOPLa+EAEkDXF7e1wm0 /zIciGcJz4Y2YhQPkNS5gKo83hs/ZWjGjdx/Nszj+nZ3C5wTIlO+hy1DApGDbJGPmw CRZLBTAU0hKzyWpeWXecxuZXT/K+F/6zQTxsJ14DUpCDlObpkS/jtMB4j0y18nPS/5 LZ1vhKyWWAA3Eo35lpS6y3A/egU1kZe6EA4mOqajgolNH3ja5e4W5E1S5XuqpV1eSs 3jthgWhd/CWju1B2XDqJvEeM2ypCag4NZFVlzl9BJeJ04vuHuq/mAQPfkJvEFn2IEk CO1pbvT4gdF9g== Message-ID: Date: Fri, 26 Jun 2026 15:43:59 +0100 Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [RFC 00/12] RFC: Devicetree-ACPI hybrid mode From: Bryan O'Donoghue To: Hans de Goede , "Rafael J . Wysocki" , Bjorn Andersson , Konrad Dybcio Cc: Srinivas Kandagatla , Krzysztof Kozlowski , Dmitry Baryshkov , Bartosz Golaszewski , Abel Vesa , linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org, linux-acpi@vger.kernel.org Reply-To: Bryan O'Donoghue References: <20260623145225.143218-1-johannes.goede@oss.qualcomm.com> <04b4f1b0-4d8f-41eb-9b6f-d90b88aec2ff@kernel.org> Content-Language: en-US Autocrypt: addr=bod@kernel.org; keydata= xsFNBGRJNSgBEADD7Vm2ZFa+v+JGJ2QYTJqQAkqis/uOHkhdFNXqpBarVBd47QU/DMNU5Rxg jedMQEmHoeDbJ6UOpjbrUQ63c5sgG1JbroHJJctwsEI75OOlekMuebEbjIJBLfgENGwPBMHv piv5TgCWr0VgYaXfp2eh2LINFywzqj823HiDPibQAXDrjzvF1ogksi/6cQZs8d4if8YQkLOr YISFouG+eR0nN1I7mUfIddXOWu6lJeTyqbWVurv58k2ekIXKaOC9ixLHFbcfYV0hOgRaTwQC B8CYF9nfqZla19iItfsN9QxN+ZdQjcRoYipp6HPCMfJlKH7GfaFcW93LKc4DKJ2lVL+pg/OQ lythZbjRPY492NG9kZ65aYstCs90uhMUEVVPuGUw7wBEku+6IEwZfrbMVKeWzLlPyM4Hv9hM 8ktxSmxWsPTPqpBC8eyeAQLalMELAyVcZlkaCtEcbj7w4l/JkYz+4l37obG8ZD+B34udBUUz MsAJ8foDFrBh2MOFA3hxD6G90D23mmWsri7pnKA2tZs92aQX7Ee+FbCyg6g5ln62Sq83ZDbf 53DdBs55EVpBadeInWmXhzCHPQx06H+CwTEjShTYIaMmBfrewvYUDKvFTC5iKQhAEUgt6i94 JsbG7NoeqcxkUMcBOEUQ3uCQG1D70ugspgXc0wd3Rimiq6535wARAQABzSFCcnlhbiBPJ0Rv bm9naHVlIDxib2RAa2VybmVsLm9yZz7CwZEEEwEIADsWIQTmk/sqq6Nt4Rerb7QicTuzoY3I OgUCZ+R+mwIbAwULCQgHAgIiAgYVCgkICwIEFgIDAQIeBwIXgAAKCRAicTuzoY3IOimUD/94 BwVEJX31JRe2sxbB/e1w2p8x1bxvTw5AeIzpV3ox7coJg1bSU2mnGuj1V4o0Yxf/3zmcJzCN VfVjwRF8Ii3GnC7uUXk2t+87piQfKTyJAYQABhZUKgoVJbjJq/S+C3XCKIyBA+EiezoUsgsA jTzwU+FzV7zVWIXFPJNtBERLwboE9w9U3KjAExOa1kSY8eLrsg6kOwlOHWy5UsQqYOjrS96M mzm2xuc1+RCjrndAyYhCnrOKvJ67HsPnBeJCjw7ImGD/U1GchwYbX8o3DO3JNHm3qfC86ZqX 2sCouENg4OzgPTtLKUrueM6xsu6KMM7gj17vxsiR3KQEoJnnMB8D1xtBofN3mFZE0wD9M24m 8yGunZbtntMCUHzIrlJgAPwKWKuGOYtA8UgMTFkccnUJtQrg9KotKtEF/FuftG9zLG9XEkt4 5ZdNgbSoLWgelu3T47mbOJ8LHhiLaCWP7yrovtVAvLUQ1BsiA42u8ECrFCFvQj9nrejE/ICv kP+uqcKtdDvP9HrIGycF1WZyfZLp0RvopKW92FLvI4I1QFWJ+wenk6+LGyJ5bzlrWzevjxmf nHcXE6sJBHrE7eijlbbImDAi3uLYN8Nd9Dm11IDAy4GAIQxSiQn0yblDhPiyGtchy80EVkCm g9k17Wol+2E2mC4DKgVdCkyUtTRSLgsJCs7BTQRkSTUoARAAuTnmWHBS6izRcEE93ajpzI7h dgQO4U3IRvOEsvIKR5NGcNEs0ngGebwsZ/lVULjN4vYU0LleqVhPBidNXUoZCN3A0F0Z2Ov8 NZdef+2EhQPBVWxFO7JBzhe8Z3ALj+wFtlg8akJjBzU56azW/iJzAobqHVrudzKoO2b1/CMg VbiAQ+RXjgfN5kY/HqYDU7mw+hXuUV9PbtX1L8xqQQac95oM9rHzKHHpiVwxTeJnGQsa+THi Kze+YET3rCoGHMvOQEJhdrucTv5FpAakKdkOFNel9FFckLRKEuWgCzhpFsjQ7xbirQgFUxG9 vlk1+q4hMRGNyEqoD6svYEeqbiUSd0oPUJeioiC3rNMRCNHLVrfZ2J6SCPkxfda08uzSdDQU 1/YPjOh8ZtQDMu7WctZ3XO288Z1gyBR49V7fbFs2w4sQxG+h/enlxqP7fdw1mjUlZjU5huCJ ielS0oEaIpmUpkugli7x4WhwLnhK2EbSoz7nLBC0y+ALUOdMlz/Y1l9xRt+bkDhpmf4O4IcI MxgZ0QMLq8rHDkGaEbsgZZHQPS58T0XE3IP30Q9SNxsruCMXtd2hYtBssf/wohc6JVsTtMg2 VYTPDPIFNZFSXupEJB7jlqpDWJ8ooJfJRLBatbjT5+mVQaMYB7Hs/t+zWYWaJKHyc8O6WLEC NUV5Tdt5EkkAEQEAAcLBdgQYAQoAIBYhBOaT+yqro23hF6tvtCJxO7Ohjcg6BQJkSTUoAhsM AAoJECJxO7Ohjcg6LuIQALnXt36OUuK43wqw6UYt0cnN6EbUqJHApAF5eNFn0jCCB2XELjSz JKJwuNAweowBdabiBniJ+501WIW+ewEsz1uby5fUQjZuCEsIkuaIluyfUFPb73qrQyAGuusd 7teA4WT+/jUku9g7lX5sVoRCrKQPkd16f6Bzfztyqyjcn43/X5yQI+wlboQ6HuKe/3I3yiOx OgmCHzOawpC9PvhEcKj79RLM3Zz5Ts5AuHpRX70Jz8Be76LwVFLp5Msx3S24ZTU1lBo2uiJ3 xSkay2lTpyVWRPx9vgcwzxGguOPJQJwsQeLb7wpoJMPpD3ERoaRii7Q7hvmxklpZjhKYWB3d t6nQ497Ek9loCrp3MIjRCSDN5xEGffiHks9yTeGMUQwO4tX8RE04uOJPkUY7uCFzFqN6/qey X3oFfPgkULMdiHofPAL1OskZSTzGPSfTYRE46NCJw8yoZBQ/oOyWeqaUQbK0wmW/g81wm8p7 LKSGEglMpiX07M1AotgvylN5C8fjbouoK+/RAMsXkk8jba6rPfuuXPaDjCyyKn6zSVHETnHW 3AJbgVY50T8STpnxayBQvWbCvu+6NOEjXCbyaOJig+5l0zlGN9XHjdANXC5HnwmyaGRL9YDq Jh2nVXVJDincOdQRdKcJjYLqaOAoWrYWSDi1iZGspHBTDrnOvfMQzzHY In-Reply-To: <04b4f1b0-4d8f-41eb-9b6f-d90b88aec2ff@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit On 26/06/2026 15:33, Bryan O'Donoghue wrote: > On 23/06/2026 15:52, Hans de Goede wrote: >> Comments, thoughts ? > > Throw out DT and just do this... > > One thing I like about this approach TBH is that you don't do the easy > thing of presuming to push the hard work into the bootloader - thus > creating a dependency on bootloader. > > We've had _alot_ of problems doing DT selectivity to get OSes installed > on arm64 laptops. You mentioned I2C-HID devices and EC controllers which > I agree are a good and obvious targets. > > I don't think this can replace a full and complete DT but, then I don't > think that should be the objective. > > Much like installing cursed OSes like Windows on "normal" laptops or x86 > machines, you'd expect to boot in ACPI mode have enough of the OS > running to install more of the OS - which I think _can_ be a viable > objective with an ACPI-DT translator. > > Sadly OpenBSD could boot all the way to console on the Qcom laptops > where Linux could not - because ACPI support was better there. > > And, we have Nvidia laptops coming too, Windows laptops which will parse > ACPI tables to boot. > > There's almost no upside in having ACPI data and not trying to make > maximal use of it, especially if you don't have a DT supplied by > antecedent boot stages. > > --- > bod > I'm going to agree with myself some more on the boot story. If you can boot Linux _at_all_ and dump out ACPI tables from the booted system you are way further along than not being able to boot without a "real" DT. Again, bootloaders have had to be educated on how to make that DT selection - a problem that isn't well solved or converged on - and even if such an agreed method were present, exactly 100% useless to you without the DT to go with it. As a Linux user I don't expect everything to work, especially so on aarch64 but, if I can get to a boot console with a screen and keyboard - I have scope to play in a way I otherwise don't - parsing DSDT from Windows and walking backwards to DT. DT _should_ be the landing zone of course but, ACPI-DT hybrid to "just boot" seems like an obvious yes to me. --- bod