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,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS 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 3A95CC5519F for ; Fri, 20 Nov 2020 08:56:56 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CE5372225B for ; Fri, 20 Nov 2020 08:56:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="sQRmtxwe" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727417AbgKTI4f (ORCPT ); Fri, 20 Nov 2020 03:56:35 -0500 Received: from mail.kernel.org ([198.145.29.99]:33852 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727208AbgKTI4e (ORCPT ); Fri, 20 Nov 2020 03:56:34 -0500 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B12DD2225B; Fri, 20 Nov 2020 08:56:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1605862593; bh=qqbbW/WYW8djm9O14VKV5AS5hfRXpB/xq6CzZTiK4jw=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=sQRmtxweZWYf8+ngQfhnlseoXKfRr6S7mM9xu4PBQ3kw3GCA2im/uHKTDtoK6yTcW hy6fVGjxdHFWBbLgKCjedTRT0Mk5c7Uns+hdfA9KqTLKZ3qkBQSds14Y0zkBEzZhoM QkzXHGewnfVrJRGVIxBdpqRioAg8u0UpJll94oKA= Received: from disco-boy.misterjones.org ([51.254.78.96] helo=www.loen.fr) by disco-boy.misterjones.org with esmtpsa (TLS1.2) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.94) (envelope-from ) id 1kg2DX-00CCR4-I8; Fri, 20 Nov 2020 08:56:31 +0000 MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII; format=flowed Content-Transfer-Encoding: 7bit Date: Fri, 20 Nov 2020 08:56:31 +0000 From: Marc Zyngier To: Neeraj Upadhyay Cc: ionela.voinescu@arm.com, valentin.schneider@arm.com, mark.rutland@arm.com, suzuki.poulose@arm.com, Will Deacon , catalin.marinas@arm.com, linux-arm-kernel@lists.infradead.org, lkml , MSM Subject: Re: AMU extension v1 support for cortex A76, A77, A78 CPUs In-Reply-To: <2cc9dd44-0b4b-94a8-155a-7a2446a1b892@codeaurora.org> References: <2cc9dd44-0b4b-94a8-155a-7a2446a1b892@codeaurora.org> User-Agent: Roundcube Webmail/1.4.9 Message-ID: <1712842eb0767e51155a5396d282102c@kernel.org> X-Sender: maz@kernel.org X-SA-Exim-Connect-IP: 51.254.78.96 X-SA-Exim-Rcpt-To: neeraju@codeaurora.org, ionela.voinescu@arm.com, valentin.schneider@arm.com, mark.rutland@arm.com, suzuki.poulose@arm.com, will@kernel.org, catalin.marinas@arm.com, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020-11-20 04:30, Neeraj Upadhyay wrote: > Hi, > > For ARM cortex A76, A77, A78 cores (which as per TRM, support AMU) > AA64PFR0[47:44] field is not set, and AMU does not get enabled for > them. > Can you please provide support for these CPUs in cpufeature.c? If that was the case, that'd be an erratum, and it would need to be documented as such. It could also be that this is an optional feature for these cores (though the TRM doesn't suggest that). Can someone at ARM confirm what is the expected behaviour of these CPUs? M. -- Jazz is not dead. It just smells funny...