From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=217.140.110.172 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793707035; b=1UhSQ/ovrtQOJ237J/n6iOnF4FkGoCX5Rb9aJbbD+thw76QxX23Scc/4Yx/06uHyR2mq JZCEyBonWEp7lqcVYE3AZQH/PqgKyu/5tpz3aspLX120+O2gXWRTcc3Gd8Hc8XceDRoSB TTSCV1dUJr2vW6ma8NMIWuHYAXBTlBdS3wDnJiBXsTn/ZNkn+g0xPGhmLqo5QHB6zBmvN +9YwrbWaaXBgVYbOe0rIB4YURN7Kpf6+kOn34PKLMLqm6daFsxvnDIOp+5rclAlnZlJ94 R3gB12Pr2tCwDlHOdkenSkZczgQETvWImTts1P2auqdVfJtfjpiJo9KqV91dzsNALyw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793707035; h=DMARC-Filter:Received:Received:DKIM-Signature:Message-ID:Date: MIME-Version:User-Agent:Subject:To:Cc:References:Content-Language: From:In-Reply-To:Content-Type:Content-Transfer-Encoding; bh=9sHZp3fDT8MdLdnD1VHW6kDwokQ+jpK3v6Y8Al7fDoQ=; b=Gzj7WPJnRQTJTeyle6FBpCU0NzDYje3o797yC6P43EvPHVXShoV9PVADo0p6YuNb2nxO +SJ8GGKyC6uEUYgtROJbXmPtlg5hqS4VjEl8C3V54TBtx+r99jihmqQOqSDPNza7GJVEe wmmXCZQiNwTbuVY3cndN1x8N5DyDie6gJ2Qjpj8rdf2tqsA5To53zMDd0ZZZVNI5Bd+oT 8kcm313oBSOv2VuTnYC3IV/99syQvEjpweG9WnsPrZbnjeh9LajDlEw7Cr8y6HZfbWHXc inRYFGe2u5Mw3avhEC6A5kbi+jl4w1LlZaKhzF2eO35xSKH1btEposgZ7edPXy1cbqQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass header.from=arm.com; spf=pass smtp.mailfrom=arm.com; dkim=pass header.d=arm.com header.i=@arm.com header.a=rsa-sha256 header.s=foss header.b=B4H5r8BQ; arc=none smtp.remote-ip=217.140.110.172 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id AF75C606A324 for ; Tue, 3 Nov 2026 11:57:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.2 smtp.subspace.kernel.org AF75C606A324 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, unprotected) header.d=arm.com header.i=@arm.com header.a=rsa-sha256 header.s=foss header.b=B4H5r8BQ 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 83B601576; Tue, 3 Nov 2026 03:57:10 -0800 (PST) Received: from [10.211.55.3] (unknown [10.57.89.242]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 941063F632; Tue, 3 Nov 2026 03:57:12 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=arm.com; s=foss; t=1793707033; bh=us62N1Qh+XhSeUo46jRNGcqbJBHkV+YCfxCCeXzVRMM=; h=Date:Subject:To:Cc:References:From:In-Reply-To:From; b=B4H5r8BQqwIt2/HR5mOlOrXioVnMbhotHQ68IoF6WbYl1/rD5FVK9o4uwhF+OoEbz gJuOzMQ9Mzd9th9Aa1Aq1cNc24iXmecXv09Bk7VS4O65x+rSCSZ6IWdUW/ZZlRTlh0 WJgsSTenzcD6HCwLfQ5rMccoRdRcuWVppmVZuqjc= Message-ID: Date: Tue, 3 Nov 2026 11:57:10 +0000 X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 User-Agent: Thunderbird Daily Subject: Re: [PATCH] arm_mpam: Only program MATCH_PMG when the monitor supports it To: Ping Li , james.morse@arm.com Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, reinette.chatre@intel.com, fenghuay@nvidia.com References: <912dbaa0-0fc0-46fb-819a-6594538b47cd@arm.com> <20261103095526.238470-1-leeonion.muyu@gmail.com> Content-Language: en-US From: Ben Horgan In-Reply-To: <20261103095526.238470-1-leeonion.muyu@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Hi Ping, On 03/11/2026 09:55, Ping Li wrote: > Hi Ben, > > Sharing the outcome of our discussions with the hardware team and Arm > support, to close this thread: > > Although the MPAM specification allows up to 8 bits of PMG, our > hardware team found that the DSU120AE and the Cortex-A520 only > propagate 1 bit of PMG. Assuming 1 bit was as good as none, and > without consulting the software team, they considered the 2 monitor > groups it would allow dispensable. So the MSC they designed > implements MSMON but no PMG support, and the bus carries PARTID only, > without the PMG bit. Thanks for sharing this information. 1 bit of PMG is common because until recently CHI didn't allow more. Ben > > Sorry for the noise again on this one, and thanks for the pointers. > > Ping