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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 64F59C433EF for ; Fri, 15 Apr 2022 02:30:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1348671AbiDOCdI (ORCPT ); Thu, 14 Apr 2022 22:33:08 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43094 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233911AbiDOCdC (ORCPT ); Thu, 14 Apr 2022 22:33:02 -0400 Received: from out30-42.freemail.mail.aliyun.com (out30-42.freemail.mail.aliyun.com [115.124.30.42]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D0C24140CD; Thu, 14 Apr 2022 19:30:35 -0700 (PDT) X-Alimail-AntiSpam: AC=PASS;BC=-1|-1;BR=01201311R171e4;CH=green;DM=||false|;DS=||;FP=0|-1|-1|-1|0|-1|-1|-1;HT=e01e04423;MF=tianjia.zhang@linux.alibaba.com;NM=1;PH=DS;RN=18;SR=0;TI=SMTPD_---0VA5GlK6_1649989831; Received: from 30.240.101.97(mailfrom:tianjia.zhang@linux.alibaba.com fp:SMTPD_---0VA5GlK6_1649989831) by smtp.aliyun-inc.com(127.0.0.1); Fri, 15 Apr 2022 10:30:32 +0800 Message-ID: <3c242430-9f6c-0e04-91fc-10132e88df99@linux.alibaba.com> Date: Fri, 15 Apr 2022 10:30:30 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0) Gecko/20100101 Thunderbird/91.7.0 Subject: Re: [PATCH] arm64/sme: Add hwcap for Scalable Matrix Extension Content-Language: en-US To: Marc Zyngier Cc: Will Deacon , Catalin Marinas , Jonathan Corbet , Joey Gouly , Vincenzo Frascino , Mark Brown , Arnd Bergmann , Anshuman Khandual , Fuad Tabba , Mark Rutland , Vladimir Murzin , James Morse , Suzuki K Poulose , Mathieu Poirier , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org References: <20220414115544.36204-1-tianjia.zhang@linux.alibaba.com> <875ynbc1je.wl-maz@kernel.org> From: Tianjia Zhang In-Reply-To: <875ynbc1je.wl-maz@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Marc, On 4/14/22 8:06 PM, Marc Zyngier wrote: > On Thu, 14 Apr 2022 12:55:44 +0100, > Tianjia Zhang wrote: >> >> Allow userspace to detect support for SME (Scalable Matrix Extension) >> by providing a hwcap for it, using the official feature name FEAT_SME, >> declared in ARM DDI 0487H.a specification. > > Err, not just that, for sure. What does this patch buys you on its > own, given that the kernel doesn't implement anything yet and that all > the SME instructions will UNDEF? > > [1] is the real deal. > > Thanks, > > M. > > [1] https://lore.kernel.org/r/20220408114328.1401034-1-broonie@kernel.org > Thanks for your suggestion, I have a very simple scenario, I can see whether the SME feature is supported in cpuinfo, it seems impractical at the moment. Kind regards, Tianjia 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 A1D72C433EF for ; Fri, 15 Apr 2022 02:31:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:Content-Type: Content-Transfer-Encoding:List-Subscribe:List-Help:List-Post:List-Archive: List-Unsubscribe:List-Id:In-Reply-To:From:References:Cc:To:Subject: MIME-Version:Date:Message-ID:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=QVJ5dKo5yVju8tR9u5v44K94iAtthe3MhLQA570vr+w=; b=cIxH3GOXxpDJdQ 1Es6RCoTt7AJDwCWJdyfjawveMgSV8x84usWRJrQspubWDTKNgmOGFyQRplFCqcGUphFMVGLsREyw Vue6DJQ9oQI458QXjENWPRJZvPUotzgEqOZCHuwd+pn1pd4WcJe3bqgqzZvL+Ynt+SZ0kqNYdVQY5 ziZ1TMGzQN6XTTWwVBDQFnHCkusjvPJisB0FfxwzX4PWbOAMchdsHkL+Q48GxrX1NZr+x074zKCgu 1WqWF4iXMkHFFqyqKo2W/DgeulrhgxgFJlkjKj6Vdhzpu1mCq/V4ufiBNH2e2zZ78dByp8+5UsvUz TDCbLRojm12V9S89f36Q==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1nfBjZ-00884h-CM; Fri, 15 Apr 2022 02:30:53 +0000 Received: from out199-14.us.a.mail.aliyun.com ([47.90.199.14]) by bombadil.infradead.org with esmtps (Exim 4.94.2 #2 (Red Hat Linux)) id 1nfBjU-0087xl-Jq for linux-arm-kernel@lists.infradead.org; Fri, 15 Apr 2022 02:30:51 +0000 X-Alimail-AntiSpam: AC=PASS; BC=-1|-1; BR=01201311R171e4; CH=green; DM=||false|; DS=||; FP=0|-1|-1|-1|0|-1|-1|-1; HT=e01e04423; MF=tianjia.zhang@linux.alibaba.com; NM=1; PH=DS; RN=18; SR=0; TI=SMTPD_---0VA5GlK6_1649989831; Received: from 30.240.101.97(mailfrom:tianjia.zhang@linux.alibaba.com fp:SMTPD_---0VA5GlK6_1649989831) by smtp.aliyun-inc.com(127.0.0.1); Fri, 15 Apr 2022 10:30:32 +0800 Message-ID: <3c242430-9f6c-0e04-91fc-10132e88df99@linux.alibaba.com> Date: Fri, 15 Apr 2022 10:30:30 +0800 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:91.0) Gecko/20100101 Thunderbird/91.7.0 Subject: Re: [PATCH] arm64/sme: Add hwcap for Scalable Matrix Extension Content-Language: en-US To: Marc Zyngier Cc: Will Deacon , Catalin Marinas , Jonathan Corbet , Joey Gouly , Vincenzo Frascino , Mark Brown , Arnd Bergmann , Anshuman Khandual , Fuad Tabba , Mark Rutland , Vladimir Murzin , James Morse , Suzuki K Poulose , Mathieu Poirier , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org References: <20220414115544.36204-1-tianjia.zhang@linux.alibaba.com> <875ynbc1je.wl-maz@kernel.org> From: Tianjia Zhang In-Reply-To: <875ynbc1je.wl-maz@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20220414_193048_934976_E0AC9765 X-CRM114-Status: GOOD ( 12.83 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Marc, On 4/14/22 8:06 PM, Marc Zyngier wrote: > On Thu, 14 Apr 2022 12:55:44 +0100, > Tianjia Zhang wrote: >> >> Allow userspace to detect support for SME (Scalable Matrix Extension) >> by providing a hwcap for it, using the official feature name FEAT_SME, >> declared in ARM DDI 0487H.a specification. > > Err, not just that, for sure. What does this patch buys you on its > own, given that the kernel doesn't implement anything yet and that all > the SME instructions will UNDEF? > > [1] is the real deal. > > Thanks, > > M. > > [1] https://lore.kernel.org/r/20220408114328.1401034-1-broonie@kernel.org > Thanks for your suggestion, I have a very simple scenario, I can see whether the SME feature is supported in cpuinfo, it seems impractical at the moment. Kind regards, Tianjia _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel