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 EC518C001B0 for ; Mon, 3 Jul 2023 04:21:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229944AbjGCEV5 (ORCPT ); Mon, 3 Jul 2023 00:21:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43244 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229638AbjGCEVz (ORCPT ); Mon, 3 Jul 2023 00:21:55 -0400 Received: from mail-pl1-x635.google.com (mail-pl1-x635.google.com [IPv6:2607:f8b0:4864:20::635]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B747D188 for ; Sun, 2 Jul 2023 21:21:52 -0700 (PDT) Received: by mail-pl1-x635.google.com with SMTP id d9443c01a7336-1b88e99673eso4634285ad.0 for ; Sun, 02 Jul 2023 21:21:52 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ventanamicro.com; s=google; t=1688358112; x=1690950112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=4yCyxORhZQcSjW6+wQb0JHG8SHx3C9xb2wsZB0KAdpI=; b=hrs8TxzWqVROATb1+OO+b2scKvbkRUaPXE8wiQC3gOk/SRBZqMzOVrYrs/f17rNkqd NywN86FFrtLqy8fAMv8FhNiblVyHqCyz6vpyZqebVrvgO3ev+tC/Cr38by1gy0KG70fA iZKR0qUNE2EJjOhywKGq6YJbVbpAvoDclCTraEjqcN+v/H4gbKfk/V7N5Ztj+uKHMSwH vpyLcw/nk4GmAR1AUZiMrfPCXtucNbwSEFzKSkyctwPD653hxDFnHtYc3bSRmNiPA+em Sn9tlpzPXU0uirbvBbONeafLp0kQ72U0lHiVMaRQUsIycH/5jX2iUvG89jTxTRzebevg vt1A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1688358112; x=1690950112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=4yCyxORhZQcSjW6+wQb0JHG8SHx3C9xb2wsZB0KAdpI=; b=Gm3GEhK/4PcaUsnsYso3Nuh4fvc+3+4nzBW9Msck3X1i2MokDDJtVi1sBpoGFhrICV maLe3z62LqgL9iei5oArdje1XJ2adiesDVXouZQj7sP5GnKenQ6MSa+UmyAcq/ImpKUq bFfPLcx7H09NdM0EeKFNzsIWGCBWybgITGFF8D/P3zPW12+sLJD3M45et5CipvaCRY++ tfs5pSE7N0uFke+MJBoHV/o17hR/uDGX+7VvaeKDquPUv/Tf4mGRUjo29j5/ziwKf9D6 ndLFRUrKzIhbMRKBVKhr1WoIHeMBES63Fw5uD0Kj7bXIMxKmT9k1AHj2ybL/wBmQG270 rGwg== X-Gm-Message-State: ABy/qLaY25t/Cq/D8cuPvNMhYHjouC6rPvRasTzJk7o2QiQjgXb70ot4 Y0XkevLfvCz0i5rpeYEfR2c30g== X-Google-Smtp-Source: APBJJlEuGGj6sFTOjEj6zdUt3a4LaoFocfAFlTOucF+WBrGmLI99yG1sSNGh9BMAqTV7PHKonGRnxA== X-Received: by 2002:a17:903:1250:b0:1b5:5059:e733 with SMTP id u16-20020a170903125000b001b55059e733mr9689916plh.17.1688358112035; Sun, 02 Jul 2023 21:21:52 -0700 (PDT) Received: from sunil-laptop ([106.51.184.72]) by smtp.gmail.com with ESMTPSA id p11-20020a170902bd0b00b001a9b29b6759sm14296207pls.183.2023.07.02.21.21.44 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 02 Jul 2023 21:21:51 -0700 (PDT) Date: Mon, 3 Jul 2023 09:51:41 +0530 From: Sunil V L To: Conor Dooley Cc: Yunhui Cui , ardb@kernel.org, palmer@dabbelt.com, paul.walmsley@sifive.com, aou@eecs.berkeley.edu, linux-riscv@lists.infradead.org, rminnich@gmail.com, mark.rutland@arm.com, lpieralisi@kernel.org, rafael@kernel.org, lenb@kernel.org, jdelvare@suse.com, yc.hung@mediatek.com, angelogioacchino.delregno@collabora.com, allen-kh.cheng@mediatek.com, pierre-louis.bossart@linux.intel.com, tinghan.shen@mediatek.com, linux-kernel@vger.kernel.org, linux-acpi@vger.kernel.org, geshijian@bytedance.com, weidong.wd@bytedance.com, alexghiti@rivosinc.com Subject: Re: [PATCH v2 1/3] riscv: obtain ACPI RSDP from FFI. Message-ID: References: <20230702095735.860-1-cuiyunhui@bytedance.com> <20230702-headway-dreamlike-d7ba39ac4910@spud> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230702-headway-dreamlike-d7ba39ac4910@spud> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Yunhui Cui, On Sun, Jul 02, 2023 at 02:47:41PM +0100, Conor Dooley wrote: > Hey, > %subject: riscv: obtain ACPI RSDP from FFI. > > This subject is a bit unhelpful because FFI would commonly mean "foreign > function interface" & you have not yet introduced it. It seems like it > would be better to do s/FFI/devicetree/ or similar. > Please also drop the full stop from the commit messages ;) > > Please use a cover letter for multi-patch series & include changelogs. > > +CC Sunil, Alex: > > Can you guys please take a look at this & see if it is something that we > want to do (ACPI without EFI)? > We have supported ACPI only with UEFI. The current booting contract between firmware and OS is to pass only one of DT or ACPI, not both. This approach brings another booting contract for Linux mixing ACPI and DT which affects RVI specs. As per policy and since it can affect multiple OSs, a frozen RVI spec is required for taking this patch into linux. So, could you please bring this topic for discussion in [1] and get agreement? Isn't it simpler to provide a minimum UEFI configuration table and stubbed BS/RS? Have you done a PoC? I am curious how do you handle EFI memory map dependencies. In case this is approved, I am wondering why do we need new FFI? [1] - https://lists.riscv.org/g/tech-brs Thanks! Sunil