From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received-SPF: Pass (sender SPF authorized) identity=mailfrom; client-ip=209.132.183.28; helo=mx1.redhat.com; envelope-from=lersek@redhat.com; receiver=edk2-devel@lists.01.org Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ml01.01.org (Postfix) with ESMTPS id E686B21188C4F for ; Mon, 26 Nov 2018 02:58:50 -0800 (PST) Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 6A26E3082A24; Mon, 26 Nov 2018 10:58:50 +0000 (UTC) Received: from lacos-laptop-7.usersys.redhat.com (ovpn-121-66.rdu2.redhat.com [10.10.121.66]) by smtp.corp.redhat.com (Postfix) with ESMTP id 25D49608DA; Mon, 26 Nov 2018 10:58:42 +0000 (UTC) To: Ard Biesheuvel , edk2-devel@lists.01.org Cc: Leif Lindholm , Eric Auger , Andrew Jones , Philippe Mathieu-Daude , Julien Grall References: <20181123121431.22353-1-ard.biesheuvel@linaro.org> <20181123121431.22353-6-ard.biesheuvel@linaro.org> From: Laszlo Ersek Message-ID: <7c30b472-4b20-e9ed-e5ef-b79f2e03cb97@redhat.com> Date: Mon, 26 Nov 2018 11:58:42 +0100 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.9.1 MIME-Version: 1.0 In-Reply-To: <20181123121431.22353-6-ard.biesheuvel@linaro.org> X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.45]); Mon, 26 Nov 2018 10:58:50 +0000 (UTC) Subject: Re: [PATCH 5/5] ArmVirtPkg: revert PcdPrePiCpuMemorySize to is default value of 48 X-BeenThere: edk2-devel@lists.01.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: EDK II Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Mon, 26 Nov 2018 10:58:51 -0000 Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit (1) s/is/its/ in $SUBJECT, please. On 11/23/18 13:14, Ard Biesheuvel wrote: > Drop the PcdPrePiCpuMemorySize definitions that limit it to 40 > bits on AArch64 targets. Indeed, after this series is applied, we still have [PcdsFixedAtBuild.ARM] gEmbeddedTokenSpaceGuid.PcdPrePiCpuMemorySize|40 left, in "ArmVirt.dsc.inc". Therefore, highlighting AArch64 in the above sentence seems justified. (2) Now, I'm noticing that the DEC default for ARM (which we continue overriding as 40) is not 48 however, but 32. Can you please remind me why we do that? This is BTW not just for my own education -- the subject seems to imply that we "generally" revert the PCD to its DEC default, *and* that the DEC default is 48. These are two statements, and for ARM, they are both false. If you agree, can you please stick AArch64 somewhere in the subject? > This is no longer appropriate now that > KVM has been enhanced to permit any IPA space size permitted by > the architecture. This means the value will revert back to its > default of 48. OK, so just to repeat my general question and documentation request, regarding EmbeddedPkg.dec / PcdPrePiCpuMemorySize, in this specific context: what *remains* affected by PcdPrePiCpuMemorySize, in ArmVirtPkg platforms? > > Contributed-under: TianoCore Contribution Agreement 1.1 > Signed-off-by: Ard Biesheuvel > --- > ArmVirtPkg/ArmVirtQemu.dsc | 4 ---- > ArmVirtPkg/ArmVirtQemuKernel.dsc | 4 ---- > 2 files changed, 8 deletions(-) > > diff --git a/ArmVirtPkg/ArmVirtQemu.dsc b/ArmVirtPkg/ArmVirtQemu.dsc > index cb59c790afcc..42f2adce80e6 100644 > --- a/ArmVirtPkg/ArmVirtQemu.dsc > +++ b/ArmVirtPkg/ArmVirtQemu.dsc > @@ -143,10 +143,6 @@ > gEmbeddedTokenSpaceGuid.PcdPrePiCpuIoSize|16 > > [PcdsFixedAtBuild.AARCH64] > - # KVM limits it IPA space to 40 bits (1 TB), so there is no need to > - # support anything bigger, even if the host hardware does > - gEmbeddedTokenSpaceGuid.PcdPrePiCpuMemorySize|40 > - > # Clearing BIT0 in this PCD prevents installing a 32-bit SMBIOS entry point, > # if the entry point version is >= 3.0. AARCH64 OSes cannot assume the > # presence of the 32-bit entry point anyway (because many AARCH64 systems > diff --git a/ArmVirtPkg/ArmVirtQemuKernel.dsc b/ArmVirtPkg/ArmVirtQemuKernel.dsc > index 434d6861a56f..d8fbf14e8f4e 100644 > --- a/ArmVirtPkg/ArmVirtQemuKernel.dsc > +++ b/ArmVirtPkg/ArmVirtQemuKernel.dsc > @@ -157,10 +157,6 @@ > # > gEmbeddedTokenSpaceGuid.PcdPrePiCpuIoSize|16 > > - # KVM limits it IPA space to 40 bits (1 TB), so there is no need to > - # support anything bigger, even if the host hardware does > - gEmbeddedTokenSpaceGuid.PcdPrePiCpuMemorySize|40 > - > [PcdsDynamicDefault.common] > gEfiMdePkgTokenSpaceGuid.PcdPlatformBootTimeOut|3 > > I'm sorry if my review comments / questions are a mess: I haven't looked at this in ages. Thanks! Laszlo