From patchwork Tue May 23 07:43:25 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luca Fancellu X-Patchwork-Id: 13251680 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.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 33A04C7EE26 for ; Tue, 23 May 2023 07:44:04 +0000 (UTC) Received: from list by lists.xenproject.org with outflank-mailman.538278.838216 (Exim 4.92) (envelope-from ) id 1q1MgU-0006TC-WB; Tue, 23 May 2023 07:43:55 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 538278.838216; Tue, 23 May 2023 07:43:54 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1q1MgU-0006SV-Pt; Tue, 23 May 2023 07:43:54 +0000 Received: by outflank-mailman (input) for mailman id 538278; Tue, 23 May 2023 07:43:53 +0000 Received: from se1-gles-flk1-in.inumbo.com ([94.247.172.50] helo=se1-gles-flk1.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1q1MgS-0003Zx-W2 for xen-devel@lists.xenproject.org; Tue, 23 May 2023 07:43:52 +0000 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by se1-gles-flk1.inumbo.com (Halon) with ESMTP id 8f3e398e-f93d-11ed-8611-37d641c3527e; Tue, 23 May 2023 09:43:51 +0200 (CEST) Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id C0552153B; Tue, 23 May 2023 00:44:35 -0700 (PDT) Received: from e125770.cambridge.arm.com (e125770.arm.com [10.1.199.1]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id D9ADB3F762; Tue, 23 May 2023 00:43:49 -0700 (PDT) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 8f3e398e-f93d-11ed-8611-37d641c3527e From: Luca Fancellu To: xen-devel@lists.xenproject.org Cc: bertrand.marquis@arm.com, wei.chen@arm.com, Stefano Stabellini , Julien Grall , Volodymyr Babchuk Subject: [PATCH v7 11/12] xen/arm: add sve property for dom0less domUs Date: Tue, 23 May 2023 08:43:25 +0100 Message-Id: <20230523074326.3035745-12-luca.fancellu@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230523074326.3035745-1-luca.fancellu@arm.com> References: <20230523074326.3035745-1-luca.fancellu@arm.com> MIME-Version: 1.0 Add a device tree property in the dom0less domU configuration to enable the guest to use SVE. Update documentation. Signed-off-by: Luca Fancellu Reviewed-by: Bertrand Marquis Reviewed-by: Michal Orzel Acked-by: Julien Grall --- Changes from v6: - Use ifdef in create_domUs and fail if 'sve' is used on systems with CONFIG_ARM64_SVE not selected (Bertrand, Julien, Jan) Changes from v5: - Stop the domain creation if SVE not supported or SVE VL errors (Julien, Bertrand) - now sve_sanitize_vl_param is renamed to sve_domctl_vl_param and returns a boolean, change the affected code. - Reworded documentation. Changes from v4: - Now it is possible to specify the property "sve" for dom0less device tree node without any value, that means the platform supported VL will be used. Changes from v3: - Now domainconfig_encode_vl is named sve_encode_vl Changes from v2: - xen_domctl_createdomain field name has changed into sve_vl and its value is the VL/128, use domainconfig_encode_vl to encode a plain VL in bits. Changes from v1: - No changes Changes from RFC: - Changed documentation --- docs/misc/arm/device-tree/booting.txt | 16 +++++++++++++++ xen/arch/arm/domain_build.c | 28 +++++++++++++++++++++++++++ 2 files changed, 44 insertions(+) diff --git a/docs/misc/arm/device-tree/booting.txt b/docs/misc/arm/device-tree/booting.txt index 3879340b5e0a..32a0e508c471 100644 --- a/docs/misc/arm/device-tree/booting.txt +++ b/docs/misc/arm/device-tree/booting.txt @@ -193,6 +193,22 @@ with the following properties: Optional. Handle to a xen,cpupool device tree node that identifies the cpupool where the guest will be started at boot. +- sve + + Optional. The `sve` property enables Arm SVE usage for the domain and sets + the maximum SVE vector length, the option is applicable only to AArch64 + guests. + A value equal to 0 disables the feature, this is the default value. + Specifying this property with no value, means that the SVE vector length + will be set equal to the maximum vector length supported by the platform. + Values above 0 explicitly set the maximum SVE vector length for the domain, + allowed values are from 128 to maximum 2048, being multiple of 128. + Please note that when the user explicitly specifies the value, if that value + is above the hardware supported maximum SVE vector length, the domain + creation will fail and the system will stop, the same will occur if the + option is provided with a non zero value, but the platform doesn't support + SVE. + - xen,enhanced A string property. Possible property values are: diff --git a/xen/arch/arm/domain_build.c b/xen/arch/arm/domain_build.c index 9202a96d9c28..ba4fe9e165ee 100644 --- a/xen/arch/arm/domain_build.c +++ b/xen/arch/arm/domain_build.c @@ -4008,6 +4008,34 @@ void __init create_domUs(void) d_cfg.max_maptrack_frames = val; } + if ( dt_get_property(node, "sve", &val) ) + { +#ifdef CONFIG_ARM64_SVE + unsigned int sve_vl_bits; + bool ret = false; + + if ( !val ) + { + /* Property found with no value, means max HW VL supported */ + ret = sve_domctl_vl_param(-1, &sve_vl_bits); + } + else + { + if ( dt_property_read_u32(node, "sve", &val) ) + ret = sve_domctl_vl_param(val, &sve_vl_bits); + else + panic("Error reading 'sve' property"); + } + + if ( ret ) + d_cfg.arch.sve_vl = sve_encode_vl(sve_vl_bits); + else + panic("SVE vector length error\n"); +#else + panic("'sve' property found, but CONFIG_ARM64_SVE not selected"); +#endif + } + /* * The variable max_init_domid is initialized with zero, so here it's * very important to use the pre-increment operator to call