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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5791AC433F5 for ; Tue, 4 Oct 2022 10:56:12 +0000 (UTC) Received: from localhost ([::1]:42660 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1offas-0003YW-HM for qemu-devel@archiver.kernel.org; Tue, 04 Oct 2022 06:56:10 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:60590) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1offYl-0001Kw-TE for qemu-devel@nongnu.org; Tue, 04 Oct 2022 06:53:59 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]:54827) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1offYh-0004pX-Dy for qemu-devel@nongnu.org; Tue, 04 Oct 2022 06:53:57 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1664880833; 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=MGoewGI2tIAIhQV36B5JUf6B4O/mb6qTfQ9wwL1whKM=; b=g//8BLhoOD3esmQGzT0u0FhjUVt4drKjIcUh5xp+/LlPcpgmcRfzx8zLVq0huVkXovLJgU mW35oqgUvUXSsPYU29ocPdvb47q/aOuIOdjEV+GjaAb5Q6dmOuYK6BHiv7/0fYsO9qd50k kGa9Hh5O4Vs+sVLOepmkeYwqQwkE3RE= 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-639-k02VsSOgNFu2ICsG6vyfNA-1; Tue, 04 Oct 2022 06:53:52 -0400 X-MC-Unique: k02VsSOgNFu2ICsG6vyfNA-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.rdu2.redhat.com [10.11.54.4]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx02.redhat.com (Postfix) with ESMTPS id C06B385A583; Tue, 4 Oct 2022 10:53:51 +0000 (UTC) Received: from localhost (unknown [10.39.193.73]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 6E5E62027061; Tue, 4 Oct 2022 10:53:51 +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 v4 5/6] hw/arm/virt: Improve high memory region address In-Reply-To: <20221004002627.59172-6-gshan@redhat.com> Organization: Red Hat GmbH References: <20221004002627.59172-1-gshan@redhat.com> <20221004002627.59172-6-gshan@redhat.com> User-Agent: Notmuch/0.37 (https://notmuchmail.org) Date: Tue, 04 Oct 2022 12:53:48 +0200 Message-ID: <87bkqroo5f.fsf@redhat.com> MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 3.1 on 10.11.54.4 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: -27 X-Spam_score: -2.8 X-Spam_bar: -- X-Spam_report: (-2.8 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Tue, Oct 04 2022, Gavin Shan wrote: > There are three high memory regions, which are VIRT_HIGH_REDIST2, > VIRT_HIGH_PCIE_ECAM and VIRT_HIGH_PCIE_MMIO. Their base addresses > are floating on highest RAM address. However, they can be disabled > in several cases. > > (1) One specific high memory region is disabled by developer by > toggling vms->highmem_{redists, ecam, mmio}. > > (2) VIRT_HIGH_PCIE_ECAM region is disabled on machine, which is > 'virt-2.12' or ealier than it. > > (3) VIRT_HIGH_PCIE_ECAM region is disabled when firmware is loaded > on 32-bits system. > > (4) One specific high memory region is disabled when it breaks the > PA space limit. > > The current implementation of virt_set_memmap() isn't comprehensive > because the space for one specific high memory region is always > reserved from the PA space for case (1), (2) and (3). In the code, > 'base' and 'vms->highest_gpa' are always increased for those three > cases. It's unnecessary since the assigned space of the disabled > high memory region won't be used afterwards. > > This improves the address assignment for those three high memory > region by skipping the address assignment for one specific high > memory region if it has been disabled in case (1), (2) and (3). > 'vms->high_compact' is false for now, meaning that we don't have > any behavior changes until it becomes configurable through property > 'compact-highmem' in next patch. > > Signed-off-by: Gavin Shan > --- > hw/arm/virt.c | 19 ++++++++++++------- > include/hw/arm/virt.h | 1 + > 2 files changed, 13 insertions(+), 7 deletions(-) > > diff --git a/hw/arm/virt.c b/hw/arm/virt.c > index 59de7b78b5..4164da49e9 100644 > --- a/hw/arm/virt.c > +++ b/hw/arm/virt.c > @@ -1715,9 +1715,6 @@ static void virt_set_high_memmap(VirtMachineState *vms, > region_base = ROUND_UP(base, extended_memmap[i].size); > region_size = extended_memmap[i].size; > > - vms->memmap[i].base = region_base; > - vms->memmap[i].size = region_size; > - > /* > * Check each device to see if they fit in the PA space, > * moving highest_gpa as we go. Maybe tweak this comment? "Check each enabled device to see if they fit in the PA space, moving highest_gpa as we go. For compatibility, move highest_gpa for disabled fitting devices as well, if the compact layout has been disabled." (Or would that be overkill?)