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 CFE96CA5FD4 for ; Fri, 2 Oct 2026 15:01:20 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: Content-Type: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=vFGkAVZALpfzlTaJiuGHcbxjtCb3qQNBWBukbUqUzxg=; b=Q0t1VSC3JijHDsMSgfR0y94U9/ 5FQpIa4mCucJp8CWzORCvamxiH4Je+D5x9LABjjqi2AvQd+bcr9mtmkfiQc9ub5ztH2IDqvaiGp1A lRk15MPbKLA9fw1ASGsS1zIKG8SI3m7pZpfowvjGzXVS8OD99lkPTEOIzx5kUNj2cJwOXNspIc4Ns nWsNRiv8DUfoHLf/n5ArdWP1XQ1sJz3hxZQJKjneWmb/mtj2L8ueXfPR4/mm1G+zzO03FQ394Vb3e p2H7A9YuQ1i5IVY52OnwG1NMIE4OHqlozzI6ENfCHdyrln1roxoxsHcT6t4g451juB4QrwoOpyECb sh6Q3AHg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1xCel8-0000000Bpxg-28K6; Fri, 02 Oct 2026 15:01:14 +0000 Received: from foss.arm.com ([217.140.110.172]) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1xCel6-0000000Bpwq-2uvz for linux-arm-kernel@lists.infradead.org; Fri, 02 Oct 2026 15:01:13 +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 65F4A497; Fri, 2 Oct 2026 08:01:06 -0700 (PDT) Received: from [10.2.212.14] (eglon.cambridge.arm.com [10.2.212.14]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id ABF393F86F; Fri, 2 Oct 2026 08:01:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1790953269; bh=2Uec7YMLA3YtX9l/GqLdQY9WQiK6dogPMfFk1LOU2Xg=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=m9ldiA8dmOka54o0DFRxxQZE8JFkOcuXOfyF4BykbrsiuJQiNrpI2xso66KWIPef+ HOiX/wkaMjY8waAGXcqEjc9YU2mhPVkfTpuSkRabqjqWfEF+6x2C42amSlQgWLk6ND Ol2Dp/TipodWyE4VKoSS93Mp9RRuLuRkrwClrNu0= Message-ID: Date: Fri, 2 Oct 2026 16:01:07 +0100 MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 03/12] arm_mpam: Set mpam_feat_msmon_mbwu_31counter when there are bandwidth counters To: Ben Horgan Cc: reinette.chatre@intel.com, fenghuay@nvidia.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, dave.martin@arm.com, andre.przywara@arm.com, Gavin Shan References: <20260917145617.2202986-1-ben.horgan@arm.com> <20260917145617.2202986-4-ben.horgan@arm.com> Content-Language: en-GB From: James Morse In-Reply-To: <20260917145617.2202986-4-ben.horgan@arm.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20261002_080112_790159_B2411351 X-CRM114-Status: GOOD ( 14.94 ) 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: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Hi Ben, On 17/09/2026 15:56, Ben Horgan wrote: > When MPAMF_MSMON_IDR.MSMON_MBWU is 1, MSMON_MBWU is present and has a VALUE > field of 31 bits. If additionally, MPAMF_MBWUMON_IDR.HAS_LONG is 1, then > MSMON_MBWU_L is also present and has a VALUE field of 44 or 63 bits as > indicated by MPAMF_MBWUMON_IDR.LWD. Hence, if there are memory bandwidth > counters then there are always 31 bit counters irrespective of whether > there also long counters. > > Set the 31 bit bandwidth counter feature bit whenever there are bandwidth > counters. Yes, that bitmap is supposed to be what is present, not what the driver is choosing to use. > diff --git a/drivers/resctrl/mpam_devices.c b/drivers/resctrl/mpam_devices.c > index 32bde94dfbc3..e349db525882 100644 > --- a/drivers/resctrl/mpam_devices.c > +++ b/drivers/resctrl/mpam_devices.c > @@ -930,9 +930,9 @@ static void mpam_ris_hw_probe(struct mpam_msc_ris *ris) > mpam_set_feature(mpam_feat_msmon_mbwu_63counter, props); > else > mpam_set_feature(mpam_feat_msmon_mbwu_44counter, props); > - } else { > - mpam_set_feature(mpam_feat_msmon_mbwu_31counter, props); > } > + > + mpam_set_feature(mpam_feat_msmon_mbwu_31counter, props); > } > } > } Reviewed-by: James Morse Thanks, James