From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 6974D318BA6 for ; Fri, 2 Oct 2026 15:01:10 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790953272; cv=none; b=txFDoVQCcz/AyHu0vZiMfnM2REaE/DkjalY3toC3Zcrw2iQmSVaXmJjQ7sg/2k6gpdTJgdL1DKUQ3q+BNLgBCSszxxkeCVQl4+rtdPHdpDQgEIkdDkNX0g36SIz5SzNQ3XaB9vZH3ni9GxqeX/woF0V/Bgyv9kGgEFMDzndl/xw= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1790953272; c=relaxed/simple; bh=2Uec7YMLA3YtX9l/GqLdQY9WQiK6dogPMfFk1LOU2Xg=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=uHu2OPb0z5eESx3L1EJX0fRkXQiysMGuBrgslgtHRK5Mhtk7yBLKTeykxtjSctnu4ZB7zX9cNgPDbwwXnxB6rZ+JUSGpn0jUhTJUi0YMbM0V61h+DB9i0bhX2GURo1VSB0DuqgOKIPFRSvw0hdG9XBCtkHV0fABjvUjl97z7D/Y= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b=m9ldiA8d; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=arm.com header.i=@arm.com header.b="m9ldiA8d" 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 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: 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 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