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 6611226B779; Wed, 10 Sep 2025 19:31:27 +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=1757532689; cv=none; b=airc6k4SKW6cOujfzuc2I412Uc8ZgerIUE7y/SXeBj0tbeMXjjIWl4YQ/uW3ik42Gy6MeaeIUnnZ7U551+3uksCL/2/gip6Gd57iWn6eiAjY9ToMtBa0HnMhDgVd0SoLfpowU5QdV9rlq4eUcVtLeXhTHOK2QDWuM0bZ40sKj3c= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757532689; c=relaxed/simple; bh=AjDTuM81hQifR+N10EEA9fVLxHXK8+EdmpykbapLIns=; h=Message-ID:Date:MIME-Version:Subject:To:Cc:References:From: In-Reply-To:Content-Type; b=CUq5qN3zX5VUwIFMmGOg6ZIU+UDkn8U4Ltrw9jhXKtj5/bHjyanvSb+r4JuqbFozoX1Ic0mbDfBw9pwhbnutVhk6PgyRqzxE2yGEw/3rCfPIK2nkEG1CUD0WWvBODs43Ya6fjhSuyJ+jKRx6yQm4oOtOqlI4mkJKl9WhduKxAhc= 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; 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 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 6A40816F2; Wed, 10 Sep 2025 12:31:18 -0700 (PDT) Received: from [10.1.197.69] (eglon.cambridge.arm.com [10.1.197.69]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id EBA5F3F694; Wed, 10 Sep 2025 12:31:20 -0700 (PDT) Message-ID: <9f00c748-c3cd-4f31-aefd-b27a4af343be@arm.com> Date: Wed, 10 Sep 2025 20:31:18 +0100 Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH 10/33] arm_mpam: Add probe/remove for mpam msc driver and kbuild boiler plate To: "Shaopeng Tan (Fujitsu)" , "linux-kernel@vger.kernel.org" , "linux-arm-kernel@lists.infradead.org" , "linux-acpi@vger.kernel.org" , "devicetree@vger.kernel.org" Cc: "shameerali.kolothum.thodi@huawei.com" , D Scott Phillips OS , "carl@os.amperecomputing.com" , "lcherian@marvell.com" , "bobo.shaobowang@huawei.com" , "baolin.wang@linux.alibaba.com" , Jamie Iles , Xin Hao , "peternewman@google.com" , "dfustini@baylibre.com" , "amitsinght@marvell.com" , David Hildenbrand , Rex Nie , Dave Martin , Koba Ko , Shanker Donthineni , "fenghuay@nvidia.com" , "baisheng.gao@unisoc.com" , Jonathan Cameron , Rob Herring , Rohit Mathew , Rafael Wysocki , Len Brown , Lorenzo Pieralisi , Hanjun Guo , Sudeep Holla , Krzysztof Kozlowski , Conor Dooley , Catalin Marinas , Will Deacon , Greg Kroah-Hartman , Danilo Krummrich References: <20250822153048.2287-1-james.morse@arm.com> <20250822153048.2287-45-james.morse@arm.com> Content-Language: en-GB From: James Morse In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Hi Shaopeng, On 09/09/2025 08:03, Shaopeng Tan (Fujitsu) wrote: >> Probing MPAM is convoluted. MSCs that are integrated with a CPU may only be >> accessible from those CPUs, and they may not be online. >> Touching the hardware early is pointless as MPAM can't be used until the >> system-wide common values for num_partid and num_pmg have been >> discovered. >> >> Start with driver probe/remove and mapping the MSC. >> diff --git a/drivers/resctrl/mpam_devices.c b/drivers/resctrl/mpam_devices.c >> new file mode 100644 index 000000000000..a0d9a699a6e7 >> --- /dev/null >> +++ b/drivers/resctrl/mpam_devices.c >> @@ -0,0 +1,336 @@ >> +static int mpam_dt_parse_resources(struct mpam_msc *msc, void *ignored) >> +{ >> + int err, num_ris = 0; >> + const u32 *ris_idx_p; >> + struct device_node *iter, *np; >> + >> + np = msc->pdev->dev.of_node; >> + for_each_child_of_node(np, iter) { >> + ris_idx_p = of_get_property(iter, "reg", NULL); >> + if (ris_idx_p) { >> + num_ris++; >> + err = mpam_dt_parse_resource(msc, iter, *ris_idx_p); >> + if (err) { >> + of_node_put(iter); >> + return err; >> + } >> + } >> + } >> + >> + if (!num_ris) >> + mpam_dt_parse_resource(msc, np, 0); > err = mpam_dt_parse_resource(msc, np, 0); Oops! Thanks for catching that, James