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 X-Spam-Level: X-Spam-Status: No, score=-6.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C5E75C4338F for ; Wed, 28 Jul 2021 10:48:49 +0000 (UTC) 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 mail.kernel.org (Postfix) with ESMTPS id 96DD760F41 for ; Wed, 28 Jul 2021 10:48:49 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 96DD760F41 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=arm.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender: Content-Transfer-Encoding:Content-Type:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:Cc:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=WLYEgPuqFTN/MK/+MH790qtxY5oNJnvySetASPey+Qs=; b=VwP/oweHMXEq/7 KrP9v8JzM8uPCXPEgv46CXoHlH2QIXzYpapNu8hf/sSL2LWTHFXoNRvA3uWm446Ep4vo+UGYGug8K oL4uSiLhCr2Js7jUq3doUG4sZk3U7313lbbOCqQvY7CNGCyHXu9GyVe6vymBSGq4iUEcBH61eecFh KqycQt5OvFg8s5qSC/UZEQ0aT4M0rSc5ymBQ3roUl9Ep6ZEgLpTsxXvzmj9Xy3QAB5b4oJUCqPj3m 30pWpLvF3IKQMEiXxVpkheSw3LFAO96vSeg88F1x51WeAWmHHClPJEll83YIv2yU7uKT46Ns4VGn9 nj4f/VGcwsxWDDLeKMRw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1m8h5D-000S90-Sa; Wed, 28 Jul 2021 10:46:40 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.94.2 #2 (Red Hat Linux)) id 1m8h59-000S8T-DA for linux-arm-kernel@lists.infradead.org; Wed, 28 Jul 2021 10:46:36 +0000 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 1A9D131B; Wed, 28 Jul 2021 03:46:33 -0700 (PDT) Received: from arm.com (usa-sjc-imap-foss1.foss.arm.com [10.121.207.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 334AB3F73D; Wed, 28 Jul 2021 03:46:32 -0700 (PDT) Date: Wed, 28 Jul 2021 11:45:11 +0100 From: Dave Martin To: Mark Brown Cc: Catalin Marinas , Will Deacon , Shuah Khan , linux-arm-kernel@lists.infradead.org, linux-kselftest@vger.kernel.org Subject: Re: [PATCH v1 1/3] kselftest/arm64: Provide a helper binary and "library" for SVE RDVL Message-ID: <20210728104511.GD1724@arm.com> References: <20210727180649.12943-1-broonie@kernel.org> <20210727180649.12943-2-broonie@kernel.org> <20210728094117.GA1724@arm.com> <20210728102035.GB4670@sirena.org.uk> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20210728102035.GB4670@sirena.org.uk> User-Agent: Mutt/1.5.23 (2014-03-12) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20210728_034635_641781_F9875C88 X-CRM114-Status: GOOD ( 17.90 ) 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-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On Wed, Jul 28, 2021 at 11:20:35AM +0100, Mark Brown wrote: > On Wed, Jul 28, 2021 at 10:41:30AM +0100, Dave Martin wrote: > > On Tue, Jul 27, 2021 at 07:06:47PM +0100, Mark Brown wrote: > > > SVE provides an instruction RDVL which reports the currently configured > > > vector length. In order to validate that our vector length configuration > > > interfaces are working correctly without having to build the C code for > > > > +.globl rdvl_sve > > > +rdvl_sve: > > > + rdvl x0, #1 > > > + ret > > > > This works, but can we use an ACLE intrinsic for this? I'm pretty GCC > > and LLVM have been up to date with that stuff for some time, though > > you'd have to check with the compiler folks. > > If we put SVE into C source files we need to build the C code with SVE > support enabled, I felt it was safer to avoid any possibility that we > might get some interference with the tests due to interactions with SVE > code generated by the compiler. It should be fine, but it's even easier > to not have to think about it at all. Good point, stick with the out-of-line asm in that case. (Also saves having to find out about the intrinsics!) Cheers ---Dave _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel