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 E3E9CEB64DA for ; Sat, 8 Jul 2023 03:59:12 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232604AbjGHD7K (ORCPT ); Fri, 7 Jul 2023 23:59:10 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59806 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229468AbjGHD7E (ORCPT ); Fri, 7 Jul 2023 23:59:04 -0400 Received: from mail-wr1-x42a.google.com (mail-wr1-x42a.google.com [IPv6:2a00:1450:4864:20::42a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 468EE1BD for ; Fri, 7 Jul 2023 20:59:03 -0700 (PDT) Received: by mail-wr1-x42a.google.com with SMTP id ffacd0b85a97d-31590e4e27aso50964f8f.1 for ; Fri, 07 Jul 2023 20:59:03 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=jrtc27.com; s=gmail.jrtc27.user; t=1688788742; x=1691380742; h=to:references:message-id:content-transfer-encoding:cc:date :in-reply-to:from:subject:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=BjvUtkQ3iSWBoIXII2O90sxep5PUoLyeZZs21ibyqjE=; b=OiGMrex+gulqtkoETcR+WaKt21x/HEwIkx++ZMV9YncQp8qrx4JouSq84CndRxpw/O II0c24xYjWbAfJB7VODNtppQjhuoqL/xuHUAWtHaZVxEdm5/NGk9Uwx1qmorxSIJAzhk 3d3qK6KzbiG0JIAWjal42kX9AYZVEsa+MkvD4H2OGIVUf9xF10lB+K8H6TNoSmJs2UeM EKbAxMx8yKJ1W6SNzv030t1zNfY4Txg4JxnE4RiAnCWnTuZc9mEoeAtmsFuc/6iD+6o0 2pP4ctBkEX3CQBOAW+7+9fgZ+p5eLMJgvIlxVsdUJ3Lw6J+uYQBax+WSl3c00B0bdSKi o2Bw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1688788742; x=1691380742; h=to:references:message-id:content-transfer-encoding:cc:date :in-reply-to:from:subject:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=BjvUtkQ3iSWBoIXII2O90sxep5PUoLyeZZs21ibyqjE=; b=dBV7O8KWxKlbYd27BEU7qan7fVN+fnOv6C2U+AOaTAWdf0fmdwiM8CiFfTPBxPTkhq QNNxdAvT9eFJOTOUkLo20OnxxUkcFpDK1nkVompo6VY0LjkM4fdxy1rVDMIgpgrqEVqp z1XkpRLLCXSN0b4OiY4cCnSt9D4kzdw82BQ2hDbWNO/fJArW+GagF1Yt1ToxAuS5/mI/ hbjCBKrUsTlswXx6uvbITn7Ya+hk7ZwToyH0tQNcHNCtm7hRD9+/LYL7FqRSEIu33CbE GCWTkotLSitGts0yrDMWqFl20fT5IpWACpGRbV5tIYAS+/HryAGsEcmqiwyIw2RvvCzj y1sw== X-Gm-Message-State: ABy/qLbF822BRM1FMCRO+QAUQlfBzv3Bf1csrQErlJAwrzBpYvCQT78t nEjwiFdct5hyihHaBAEeg8xcXg== X-Google-Smtp-Source: APBJJlHjSZhzcSxXjiOPVSwvNw3AfG2kOjO024Ri9E7Ji/WRfODTBuXMu9V/vShqT5QR7KrOwOjXvg== X-Received: by 2002:adf:dd92:0:b0:314:53a4:42a5 with SMTP id x18-20020adfdd92000000b0031453a442a5mr5247095wrl.51.1688788741411; Fri, 07 Jul 2023 20:59:01 -0700 (PDT) Received: from smtpclient.apple ([131.111.5.246]) by smtp.gmail.com with ESMTPSA id i4-20020adfefc4000000b003143be36d99sm5915882wrp.58.2023.07.07.20.58.59 (version=TLS1_2 cipher=ECDHE-ECDSA-AES128-GCM-SHA256 bits=128/128); Fri, 07 Jul 2023 20:59:00 -0700 (PDT) Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3731.600.7\)) Subject: Re: [External] [PATCH v3 0/4] Obtain SMBIOS and ACPI entry from FFI From: Jessica Clarke In-Reply-To: Date: Sat, 8 Jul 2023 04:58:49 +0100 Cc: Dong Wei , Conor Dooley , =?utf-8?B?6JGb5aOr5bu6?= , Sunil V L , Conor Dooley , ron minnich , Palmer Dabbelt , Ard Biesheuvel , "kernel@esmil.dk" , Paul Walmsley , "aou@eecs.berkeley.edu" , "linux-riscv@lists.infradead.org" , Mark Rutland , "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" , "weidong.wd@bytedance.com" Content-Transfer-Encoding: quoted-printable Message-Id: <9F6A932E-6FFE-4CF1-BF20-D5D80AC26F37@jrtc27.com> References: <20230707-attach-conjuror-306d967347ce@wendy> <20230707-gargle-enjoyable-f9f7f87fc7ea@spud> To: =?utf-8?B?6L+Q6L6J5bSU?= X-Mailer: Apple Mail (2.3731.600.7) Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 8 Jul 2023, at 04:22, =E8=BF=90=E8=BE=89=E5=B4=94 = wrote: >=20 > Hey, >=20 > On Sat, Jul 8, 2023 at 12:39=E2=80=AFAM Dong Wei = wrote: >>=20 >>=20 >>=20 >>> I don't think that's the limitation on RISC-V. BTW, how does OSPM = find the >>=20 >>> RSDP on ARM systems? Does it meet 5.2.5? >>=20 >>>=20 >>=20 >>=20 >>=20 >> On Arm systems today, the ACPI RSDP is found using the UEFI = Configuration Table. This is true for all Arm SystemReady compliant = systems: 1) SystemReady LS: LBBRv1 is using a minimal UEFI FW to load = LinuxBoot, that minimal UEFI FW is producing the UEFI Configuration = Table. We are working on LBBRv2. LBBRv2 is based on Coreboot loading = LinuxBoot. But we do not have a way today to get CoreBoot to produce = this pointer to ACPI RSDP. Arm does not support x86 E820 BIOS interface. = 2) SystemReady IR: this solution uses DT rather than ACPI. 3) = SystemReady ES: this solution can use UBoot or EDK2, and it requires = ACPI. Since both UBoot and EDK2 support UEFI now, so ACPI RSDP can be = found using the UEFI Configuration Table. 4) SystemReady SR: this = solution typically uses EDK2 and requires ACPI, so no issue finding RSDP = via UEFI Configuration Table. >=20 > Looks like ARM has a similar problem, If by =E2=80=9Cproblem=E2=80=9D you mean =E2=80=9Cthere=E2=80=99s only = one standard that I=E2=80=99m choosing to not follow=E2=80=9D. > Indeed, as Ron said, many companies may encounter this issue. More > developers are embracing Coreboot. When the platform guided by > Coreboot requires ACPI support, they are faced with how to pass ACPI > RSDP to Linux. It=E2=80=99s called UEFI. EBBR=E2=80=99s requirements are pretty = minimal. Please just follow the one standard. Having one standard is good for compatibility; there needs to be a very good reason beyond =E2=80=9CI = don=E2=80=99t like the standard=E2=80=9D to introduce a competing one and the = fragmentation that results from it that becomes shared pain for the ecosystem. Jess >> So the ACPI RSDP issue only exist if we want to remove the minimum = UEFI FW and go to CoreBoot completely to load LinuxBoot. We are = currently exploring how to solve that issue=E2=80=A6 >>=20 >>=20 >>=20 >> -DW >>=20 >>=20 >>=20 >> IMPORTANT NOTICE: The contents of this email and any attachments are = confidential and may also be privileged. If you are not the intended = recipient, please notify the sender immediately and do not disclose the = contents to any other person, use it for any purpose, or store or copy = the information in any medium. Thank you. >=20 > Thanks, > Yunhui