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 3121FD29FF0 for ; Wed, 14 Jan 2026 11:21:07 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vfyvX-0002kP-GQ; Wed, 14 Jan 2026 06:20:43 -0500 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 1vfyuv-0002Sf-1X; Wed, 14 Jan 2026 06:20:09 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vfyus-0004tZ-MA; Wed, 14 Jan 2026 06:20:00 -0500 Received: from mail.maildlp.com (unknown [172.18.224.83]) by frasgout.his.huawei.com (SkyGuard) with ESMTPS id 4drkCq00hKzHnHDS; Wed, 14 Jan 2026 19:19:34 +0800 (CST) Received: from dubpeml100005.china.huawei.com (unknown [7.214.146.113]) by mail.maildlp.com (Postfix) with ESMTPS id C8F1A40572; Wed, 14 Jan 2026 19:19:54 +0800 (CST) Received: from localhost (10.203.177.15) by dubpeml100005.china.huawei.com (7.214.146.113) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.36; Wed, 14 Jan 2026 11:19:53 +0000 Date: Wed, 14 Jan 2026 11:19:52 +0000 To: Shameer Kolothum CC: , , , , , , , , , , , , , , , , , , Subject: Re: [PATCH v7 30/36] hw/arm/smmuv3-accel: Add property to specify OAS bits Message-ID: <20260114111952.0000228a@huawei.com> In-Reply-To: <20260111195508.106943-31-skolothumtho@nvidia.com> References: <20260111195508.106943-1-skolothumtho@nvidia.com> <20260111195508.106943-31-skolothumtho@nvidia.com> X-Mailer: Claws Mail 4.3.0 (GTK 3.24.42; x86_64-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.203.177.15] X-ClientProxiedBy: lhrpeml100009.china.huawei.com (7.191.174.83) To dubpeml100005.china.huawei.com (7.214.146.113) Received-SPF: pass client-ip=185.176.79.56; envelope-from=jonathan.cameron@huawei.com; helo=frasgout.his.huawei.com X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham 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: , Reply-to: Jonathan Cameron From: Jonathan Cameron via Errors-To: qemu-arm-bounces+qemu-arm=archiver.kernel.org@nongnu.org Sender: qemu-arm-bounces+qemu-arm=archiver.kernel.org@nongnu.org On Sun, 11 Jan 2026 19:53:16 +0000 Shameer Kolothum wrote: > QEMU SMMUv3 currently sets the output address size (OAS) to 44 bits. > With accelerator mode enabled, a device may use SVA, where CPU page tables > are shared with the SMMU, requiring an OAS at least as large as the > CPU=E2=80=99s output address size. A user option is added to configure th= is. >=20 > However, the OAS value advertised by the virtual SMMU must remain > compatible with the capabilities of the host SMMUv3. In accelerated > mode, the host SMMU performs stage-2 translation and must be able to > consume the intermediate physical addresses (IPA) produced by stage-1. >=20 > The OAS exposed by the virtual SMMU defines the maximum IPA width that > stage-1 translations may generate. For AArch64 implementations, the > maximum usable IPA size on the host SMMU is determined by its own OAS. > Check that the configured OAS does not exceed what the host SMMU > can safely support. >=20 > Tested-by: Zhangfei Gao > Reviewed-by: Nicolin Chen > Reviewed-by: Eric Auger > Signed-off-by: Shameer Kolothum Reviewed-by: Jonathan Cameron 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 29AE7D29FEC for ; Wed, 14 Jan 2026 11:21:22 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vfyvA-0002YF-LS; Wed, 14 Jan 2026 06:20:17 -0500 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 1vfyuv-0002Sf-1X; Wed, 14 Jan 2026 06:20:09 -0500 Received: from frasgout.his.huawei.com ([185.176.79.56]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vfyus-0004tZ-MA; Wed, 14 Jan 2026 06:20:00 -0500 Received: from mail.maildlp.com (unknown [172.18.224.83]) by frasgout.his.huawei.com (SkyGuard) with ESMTPS id 4drkCq00hKzHnHDS; Wed, 14 Jan 2026 19:19:34 +0800 (CST) Received: from dubpeml100005.china.huawei.com (unknown [7.214.146.113]) by mail.maildlp.com (Postfix) with ESMTPS id C8F1A40572; Wed, 14 Jan 2026 19:19:54 +0800 (CST) Received: from localhost (10.203.177.15) by dubpeml100005.china.huawei.com (7.214.146.113) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1544.36; Wed, 14 Jan 2026 11:19:53 +0000 Date: Wed, 14 Jan 2026 11:19:52 +0000 To: Shameer Kolothum CC: , , , , , , , , , , , , , , , , , , Subject: Re: [PATCH v7 30/36] hw/arm/smmuv3-accel: Add property to specify OAS bits Message-ID: <20260114111952.0000228a@huawei.com> In-Reply-To: <20260111195508.106943-31-skolothumtho@nvidia.com> References: <20260111195508.106943-1-skolothumtho@nvidia.com> <20260111195508.106943-31-skolothumtho@nvidia.com> X-Mailer: Claws Mail 4.3.0 (GTK 3.24.42; x86_64-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Originating-IP: [10.203.177.15] X-ClientProxiedBy: lhrpeml100009.china.huawei.com (7.191.174.83) To dubpeml100005.china.huawei.com (7.214.146.113) Received-SPF: pass client-ip=185.176.79.56; envelope-from=jonathan.cameron@huawei.com; helo=frasgout.his.huawei.com X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001, 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: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-to: Jonathan Cameron From: Jonathan Cameron via qemu development Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Sun, 11 Jan 2026 19:53:16 +0000 Shameer Kolothum wrote: > QEMU SMMUv3 currently sets the output address size (OAS) to 44 bits. > With accelerator mode enabled, a device may use SVA, where CPU page tables > are shared with the SMMU, requiring an OAS at least as large as the > CPU=E2=80=99s output address size. A user option is added to configure th= is. >=20 > However, the OAS value advertised by the virtual SMMU must remain > compatible with the capabilities of the host SMMUv3. In accelerated > mode, the host SMMU performs stage-2 translation and must be able to > consume the intermediate physical addresses (IPA) produced by stage-1. >=20 > The OAS exposed by the virtual SMMU defines the maximum IPA width that > stage-1 translations may generate. For AArch64 implementations, the > maximum usable IPA size on the host SMMU is determined by its own OAS. > Check that the configured OAS does not exceed what the host SMMU > can safely support. >=20 > Tested-by: Zhangfei Gao > Reviewed-by: Nicolin Chen > Reviewed-by: Eric Auger > Signed-off-by: Shameer Kolothum Reviewed-by: Jonathan Cameron