From mboxrd@z Thu Jan 1 00:00:00 1970 Received: by 2002:a17:906:43c7:b0:78d:9f02:16a1 with SMTP id j7csp3996325ejn; Tue, 25 Oct 2022 03:55:36 -0700 (PDT) X-Google-Smtp-Source: AMsMyM7ccPK/pUckgs3SEl3R1MF8EKmiuigW1FFQ8rUuHGcdTm6N9zhcmd4gfKqliOQm5GJcYLOn X-Received: by 2002:a05:620a:f12:b0:6cf:bf70:9ee4 with SMTP id v18-20020a05620a0f1200b006cfbf709ee4mr26732727qkl.608.1666695335977; Tue, 25 Oct 2022 03:55:35 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1666695335; cv=none; d=google.com; s=arc-20160816; b=pkqFrIdAHyGsewMmJWKmumZYxAmAMN9j9QlvTL+3zM77yBCZPOBKJXma3lhIVvacrw qhOT4dMP3ZyDILA5zMP08AL9tJNGAgN6Xi9qWy6jjCruU18pPNECxHa+/LweRfXWHH83 Nz6RVHfQcwDDiUPpB4Wf3wrHtCJwHYK0vSGN1eQ5rn4kGfNROj4kGt1Y+GKYWwbwTBQa rImElAxIC/iPLmhQivT5hTDYDEADmsa0RpWN31HG1ySlIYeuECy0ZgoDBhjCWgP+MEN6 sGzC9XRnPiamLA/vUj3bajCUOMH4DZsvgM6vASrfKUsN4h2FUXoJcVJm7oy5nGLO6HGk F6aQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=errors-to:sender:list-subscribe:list-help:list-post:list-archive :list-unsubscribe:list-id:precedence:mime-version:message-id:date :user-agent:references:organization:in-reply-to:subject:cc:to:from :dkim-signature; bh=K2zfXLXFk2e8p28x8um6eeBSVBVMhs2nk/4C/NGHwyA=; b=MxZ71QlsViqRqm351XApWdiN34Gpk6d5jiVcf3XqsYauhVKjAWU7bMj4lZXlH4Q8Ou H18A5no6cHq48EVTPOO1RD/Nqz3Xo8qjJhvKm/v6UbD6f66k4yDiYa/V7rKZ5ODPscBk XeZvLYprKyi0vshZyfRy3oRabNrJgLgjN2wSBs4bMNXs022fHJTko23uQOiYG7h39fCz HkCkOOGYx2SLKl8s92CtkOWr7TTICwiwdqN0vrHozF8ulovK6rVPd65bidsYbVvSvlAN 0le8QL7K/I6aQAY7s2yHyUjCFcligZqydHSDuFL9xxhlVV4OX1LOXYrlpeRbHziG9Hrg I5Tw== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=DX9Hu9Ve; spf=pass (google.com: domain of qemu-arm-bounces+alex.bennee=linaro.org@nongnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom="qemu-arm-bounces+alex.bennee=linaro.org@nongnu.org"; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Return-Path: Received: from lists.gnu.org (lists.gnu.org. [209.51.188.17]) by mx.google.com with ESMTPS id h188-20020a37b7c5000000b006cfbabafc1csi1575523qkf.222.2022.10.25.03.55.35 for (version=TLS1_2 cipher=ECDHE-ECDSA-CHACHA20-POLY1305 bits=256/256); Tue, 25 Oct 2022 03:55:35 -0700 (PDT) Received-SPF: pass (google.com: domain of qemu-arm-bounces+alex.bennee=linaro.org@nongnu.org designates 209.51.188.17 as permitted sender) client-ip=209.51.188.17; Authentication-Results: mx.google.com; dkim=pass header.i=@redhat.com header.s=mimecast20190719 header.b=DX9Hu9Ve; spf=pass (google.com: domain of qemu-arm-bounces+alex.bennee=linaro.org@nongnu.org designates 209.51.188.17 as permitted sender) smtp.mailfrom="qemu-arm-bounces+alex.bennee=linaro.org@nongnu.org"; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=redhat.com Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1onHa0-00082r-4T; Tue, 25 Oct 2022 06:54:44 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1onHZu-000760-TI for qemu-arm@nongnu.org; Tue, 25 Oct 2022 06:54:39 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1onHZq-0005zK-Dg for qemu-arm@nongnu.org; Tue, 25 Oct 2022 06:54:35 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1666695273; 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: in-reply-to:in-reply-to:references:references; bh=K2zfXLXFk2e8p28x8um6eeBSVBVMhs2nk/4C/NGHwyA=; b=DX9Hu9Ve+dWaaAofEVoK0j7AaYYe3Mq83Ii+f9QvvU2tf5qjIF+7syT9YyJLi39og1wy93 ins3x1MwxBoZuOww3xPEmijWStXuloIQ9pX74Z7EvXk66tbZui5bc2FpcY9KYo1B6uBfZW YT4qcR5Rzbf4PIuKz35TafRCM3CseGM= Received: from mimecast-mx02.redhat.com (mimecast-mx02.redhat.com [66.187.233.88]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id us-mta-369-EHqfgFKnMKm22yMce_7KSA-1; Tue, 25 Oct 2022 06:54:28 -0400 X-MC-Unique: EHqfgFKnMKm22yMce_7KSA-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.rdu2.redhat.com [10.11.54.3]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id AB4FA85A59D; Tue, 25 Oct 2022 10:54:27 +0000 (UTC) Received: from localhost (unknown [10.39.193.32]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 5091B10A58CE; Tue, 25 Oct 2022 10:54:27 +0000 (UTC) From: Cornelia Huck To: Gavin Shan , qemu-arm@nongnu.org Cc: qemu-devel@nongnu.org, maz@kernel.org, eric.auger@redhat.com, zhenyzha@redhat.com, richard.henderson@linaro.org, peter.maydell@linaro.org, shan.gavin@gmail.com Subject: Re: [PATCH v6 7/7] hw/arm/virt: Add properties to disable high memory regions In-Reply-To: <20221024035416.34068-8-gshan@redhat.com> Organization: Red Hat GmbH References: <20221024035416.34068-1-gshan@redhat.com> <20221024035416.34068-8-gshan@redhat.com> User-Agent: Notmuch/0.37 (https://notmuchmail.org) Date: Tue, 25 Oct 2022 12:54:25 +0200 Message-ID: <874jvsfa1q.fsf@redhat.com> MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.1 on 10.11.54.3 Received-SPF: pass client-ip=170.10.129.124; envelope-from=cohuck@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -32 X-Spam_score: -3.3 X-Spam_bar: --- X-Spam_report: (-3.3 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.517, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H2=-0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=unavailable autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-arm@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "Qemu-arm" Errors-To: qemu-arm-bounces+alex.bennee=linaro.org@nongnu.org X-TUID: iittAhokkOL5 On Mon, Oct 24 2022, Gavin Shan wrote: > These 3 high memory regions are usually enabled by default, but s/These 3/The/ ? > they may be not used. For example, VIRT_HIGH_GIC_REDIST2 isn't > needed by GICv2. This leads to waste in the PA space. When building the command line, do we have enough information on when the regions provide something useful, and when they just waste space? > > Add properties to allow users selectively disable them if needed: > "highmem-redists", "highmem-ecam", "highmem-mmio". > > Suggested-by: Marc Zyngier > Signed-off-by: Gavin Shan > --- > docs/system/arm/virt.rst | 12 ++++++++ > hw/arm/virt.c | 64 ++++++++++++++++++++++++++++++++++++++++ > 2 files changed, 76 insertions(+) > > diff --git a/docs/system/arm/virt.rst b/docs/system/arm/virt.rst > index 4454706392..a1668a969d 100644 > --- a/docs/system/arm/virt.rst > +++ b/docs/system/arm/virt.rst > @@ -98,6 +98,18 @@ compact-highmem > Set ``on``/``off`` to enable/disable the compact layout for high memory regions. > The default is ``on`` for machine types later than ``virt-7.2``. > > +highmem-redists > + Set ``on``/``off`` to enable/disable the high memry region for GICv3/4 s/memry/memory/ > + redistributor. The default is ``on``. Do we need to add a note about what effects setting this to "off" may have, e.g. "Setting this to ``off`` may limit the maximum number of cpus." or so? And/or "Setting this to ``off`` when using GICv2 will save some space."? > + > +highmem-ecam > + Set ``on``/``off`` to enable/disable the high memry region for PCI ECAM. s/memry/memory/ > + The default is ``on`` for machine types later than ``virt-3.0``. > + > +highmem-mmio > + Set ``on``/``off`` to enable/disable the high memry region for PCI MMIO. s/memry/memory/ > + The default is ``on``. > + > gic-version > Specify the version of the Generic Interrupt Controller (GIC) to provide. > Valid values are: