From patchwork Thu Jun 27 19:52:56 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Atish Patra X-Patchwork-Id: 11020433 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id E3F4D14BB for ; Thu, 27 Jun 2019 19:55:41 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id D6AD128385 for ; Thu, 27 Jun 2019 19:55:41 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id C9CA228553; Thu, 27 Jun 2019 19:55:41 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 4573528385 for ; Thu, 27 Jun 2019 19:55:41 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=iP+nKavNCjqOs88ocwSFQSuW8+js9/E5x5JlmN0Bk00=; b=t0UgfBNC58GNx4 pM+g6G/+uj6OPeMh58gqlU+2rQ1iS5cQaHwEpQx60N/6IEXwOyeqlXSJJ2BSVFy0l0u3v6Pala59q 7qNvtDRCl5uaS2dzFyecq7ESe+9lu2PgHXB9b5VggwrXDFEe3doheQduMiBRO+8GdCb3bNW6MWLeS 0MvYj7a+N5/uyZWROE7P0x1y+q5zpEOyprMI6wqh3NDhNEL4v+C1sumB5mrIpau0kcUgdqJo4rJaC miyjfxsresb3A/Hc/wbVH1/Qg5FFG8fUHANTYMsHvGbuoY+aHzM0sN1FxAq7Pry0PBZHnG5VkLqPK HiuIIUqzjGrU7f/uCElw==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1hgaUa-0004PH-0P; Thu, 27 Jun 2019 19:55:36 +0000 Received: from esa6.hgst.iphmx.com ([216.71.154.45]) by bombadil.infradead.org with esmtps (Exim 4.92 #3 (Red Hat Linux)) id 1hgaUR-0004KX-22; Thu, 27 Jun 2019 19:55:28 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=wdc.com; i=@wdc.com; q=dns/txt; s=dkim.wdc.com; t=1561665327; x=1593201327; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=R4jfjZMxUWSzFwisiuVjBFLXxDAnXEO77dQqxAyI1wE=; b=pzkqQ0kxyU8Ri51rRUJUnIm9hB2sJaReKXEWJwqpvHdqxZ5Pcb4ZL6Nr vBCVdpAhVjBoG32FDznAHuHwbTEYmQVB7KK1k75F4pfuTcHn8uA6aU0FL iAHl/aM5u6vGiAZPxv48KNpRf8QASZ9IxR6kWvXBzkJmt7qDb+2dRBQiE fLjY2Eb9gZu+BFFQW5CCjQ4vsh7/tQYLsvfh4sKhV2BpVVOhlpKg3F2aA MU1Pb1NeM2FFQZlBzSbLwN2ufqq+goU3hevUZza2ZG1N0t+iAYbX5ltLA SGnPqZ3jujAuxVUJbLDVkpu6W2Z+ZcwmBQRSDBpI0/WeNtqIlFLVEMdKH w==; X-IronPort-AV: E=Sophos;i="5.63,424,1557158400"; d="scan'208";a="113353772" Received: from uls-op-cesaip02.wdc.com (HELO uls-op-cesaep02.wdc.com) ([199.255.45.15]) by ob1.hgst.iphmx.com with ESMTP; 28 Jun 2019 03:55:25 +0800 IronPort-SDR: OflgjNsBWzHv1FTECYb6DjK9vxuoGepNdrk4xzHc2NUVqS7cweMhasofFoXiaw4Wop16mgW0SS PMT4X+D78EU2KXPjZCm3mjG8cYjAJwKBQZ9j+/Vpr24t1vfcYg4ZU5v5ZBkbK3qJE6NlWh2AU9 v24ZzOl5v5rzEJsgtYcV+2+jiMdgxsVxduPPdkDIlDlFgK6F/7rchiS8ZDWRplrzhV6hlE3lKq RQVv37QyIXv8SWr5e+LBIDQNehd7h1ZqcfOVpiKklR/1ibx1Up+PNR3cjz9uV0uBoc7Bo1mrHA eWBLBz+TD3a5xs6uMxmUaIYF Received: from uls-op-cesaip01.wdc.com ([10.248.3.36]) by uls-op-cesaep02.wdc.com with ESMTP; 27 Jun 2019 12:54:38 -0700 IronPort-SDR: zrZX6RAbOPoSs5QMZIqfjIVfLPRAfo+phS5jzwXRWAwg0bCtmLWKKOjf5WM/+ysKs88/8jV8D8 GgQ3+6aktI6mnATTDgLps2zNlvwrwikyl1o+hnJ9W+fsGZ8kFR5LOtP7IAZsespf9vIuLZjiYa WFcPoI5TYkJVnyLYWLB8aMxqzD0vx1PP72A8kIWdiQUPlJGZpouXJXliay5wvI/nDfLD2olu4+ NeVibRmlcwz/JPb2fSEFN+IVh2bBKk6khcBif0vGeMBP6FlKZDMYZtGeJHolZ65m6FEoLDE2Ke Vq0= Received: from jedi-01.sdcorp.global.sandisk.com (HELO jedi-01.int.fusionio.com) ([10.11.143.218]) by uls-op-cesaip01.wdc.com with ESMTP; 27 Jun 2019 12:55:25 -0700 From: Atish Patra To: linux-kernel@vger.kernel.org Subject: [PATCH v8 1/7] Documentation: DT: arm: add support for sockets defining package boundaries Date: Thu, 27 Jun 2019 12:52:56 -0700 Message-Id: <20190627195302.28300-2-atish.patra@wdc.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20190627195302.28300-1-atish.patra@wdc.com> References: <20190627195302.28300-1-atish.patra@wdc.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190627_125527_168358_2411B2B0 X-CRM114-Status: GOOD ( 18.04 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , "Rafael J. Wysocki" , "Peter Zijlstra \(Intel\)" , Catalin Marinas , Linus Walleij , Palmer Dabbelt , Will Deacon , Atish Patra , Mauro Carvalho Chehab , linux-riscv@lists.infradead.org, Will Deacon , Ingo Molnar , Rob Herring , Anup Patel , Russell King , Morten Rasmussen , devicetree@vger.kernel.org, Albert Ou , Johan Hovold , Rob Herring , Paul Walmsley , Thomas Gleixner , linux-arm-kernel@lists.infradead.org, Greg Kroah-Hartman , Otto Sabart , Sudeep Holla , "David S. Miller" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP From: Sudeep Holla The current ARM DT topology description provides the operating system with a topological view of the system that is based on leaf nodes representing either cores or threads (in an SMT system) and a hierarchical set of cluster nodes that creates a hierarchical topology view of how those cores and threads are grouped. However this hierarchical representation of clusters does not allow to describe what topology level actually represents the physical package or the socket boundary, which is a key piece of information to be used by an operating system to optimize resource allocation and scheduling. Lets add a new "socket" node type in the cpu-map node to describe the same. Signed-off-by: Sudeep Holla Reviewed-by: Rob Herring --- .../devicetree/bindings/arm/topology.txt | 172 ++++++++++-------- 1 file changed, 99 insertions(+), 73 deletions(-) diff --git a/Documentation/devicetree/bindings/arm/topology.txt b/Documentation/devicetree/bindings/arm/topology.txt index b0d80c0fb265..3b8febb46dad 100644 --- a/Documentation/devicetree/bindings/arm/topology.txt +++ b/Documentation/devicetree/bindings/arm/topology.txt @@ -9,6 +9,7 @@ ARM topology binding description In an ARM system, the hierarchy of CPUs is defined through three entities that are used to describe the layout of physical CPUs in the system: +- socket - cluster - core - thread @@ -63,21 +64,23 @@ nodes are listed. The cpu-map node's child nodes can be: - - one or more cluster nodes + - one or more cluster nodes or + - one or more socket nodes in a multi-socket system Any other configuration is considered invalid. -The cpu-map node can only contain three types of child nodes: +The cpu-map node can only contain 4 types of child nodes: +- socket node - cluster node - core node - thread node whose bindings are described in paragraph 3. -The nodes describing the CPU topology (cluster/core/thread) can only -be defined within the cpu-map node and every core/thread in the system -must be defined within the topology. Any other configuration is +The nodes describing the CPU topology (socket/cluster/core/thread) can +only be defined within the cpu-map node and every core/thread in the +system must be defined within the topology. Any other configuration is invalid and therefore must be ignored. =========================================== @@ -85,26 +88,44 @@ invalid and therefore must be ignored. =========================================== cpu-map child nodes must follow a naming convention where the node name -must be "clusterN", "coreN", "threadN" depending on the node type (ie -cluster/core/thread) (where N = {0, 1, ...} is the node number; nodes which -are siblings within a single common parent node must be given a unique and +must be "socketN", "clusterN", "coreN", "threadN" depending on the node type +(ie socket/cluster/core/thread) (where N = {0, 1, ...} is the node number; nodes +which are siblings within a single common parent node must be given a unique and sequential N value, starting from 0). cpu-map child nodes which do not share a common parent node can have the same name (ie same number N as other cpu-map child nodes at different device tree levels) since name uniqueness will be guaranteed by the device tree hierarchy. =========================================== -3 - cluster/core/thread node bindings +3 - socket/cluster/core/thread node bindings =========================================== -Bindings for cluster/cpu/thread nodes are defined as follows: +Bindings for socket/cluster/cpu/thread nodes are defined as follows: + +- socket node + + Description: must be declared within a cpu-map node, one node + per physical socket in the system. A system can + contain single or multiple physical socket. + The association of sockets and NUMA nodes is beyond + the scope of this bindings, please refer [2] for + NUMA bindings. + + This node is optional for a single socket system. + + The socket node name must be "socketN" as described in 2.1 above. + A socket node can not be a leaf node. + + A socket node's child nodes must be one or more cluster nodes. + + Any other configuration is considered invalid. - cluster node Description: must be declared within a cpu-map node, one node per cluster. A system can contain several layers of - clustering and cluster nodes can be contained in parent - cluster nodes. + clustering within a single physical socket and cluster + nodes can be contained in parent cluster nodes. The cluster node name must be "clusterN" as described in 2.1 above. A cluster node can not be a leaf node. @@ -164,90 +185,93 @@ Bindings for cluster/cpu/thread nodes are defined as follows: 4 - Example dts =========================================== -Example 1 (ARM 64-bit, 16-cpu system, two clusters of clusters): +Example 1 (ARM 64-bit, 16-cpu system, two clusters of clusters in a single +physical socket): cpus { #size-cells = <0>; #address-cells = <2>; cpu-map { - cluster0 { + socket0 { cluster0 { - core0 { - thread0 { - cpu = <&CPU0>; - }; - thread1 { - cpu = <&CPU1>; + cluster0 { + core0 { + thread0 { + cpu = <&CPU0>; + }; + thread1 { + cpu = <&CPU1>; + }; }; - }; - core1 { - thread0 { - cpu = <&CPU2>; - }; - thread1 { - cpu = <&CPU3>; + core1 { + thread0 { + cpu = <&CPU2>; + }; + thread1 { + cpu = <&CPU3>; + }; }; }; - }; - cluster1 { - core0 { - thread0 { - cpu = <&CPU4>; - }; - thread1 { - cpu = <&CPU5>; + cluster1 { + core0 { + thread0 { + cpu = <&CPU4>; + }; + thread1 { + cpu = <&CPU5>; + }; }; - }; - - core1 { - thread0 { - cpu = <&CPU6>; - }; - thread1 { - cpu = <&CPU7>; - }; - }; - }; - }; - cluster1 { - cluster0 { - core0 { - thread0 { - cpu = <&CPU8>; - }; - thread1 { - cpu = <&CPU9>; - }; - }; - core1 { - thread0 { - cpu = <&CPU10>; - }; - thread1 { - cpu = <&CPU11>; + core1 { + thread0 { + cpu = <&CPU6>; + }; + thread1 { + cpu = <&CPU7>; + }; }; }; }; cluster1 { - core0 { - thread0 { - cpu = <&CPU12>; + cluster0 { + core0 { + thread0 { + cpu = <&CPU8>; + }; + thread1 { + cpu = <&CPU9>; + }; }; - thread1 { - cpu = <&CPU13>; + core1 { + thread0 { + cpu = <&CPU10>; + }; + thread1 { + cpu = <&CPU11>; + }; }; }; - core1 { - thread0 { - cpu = <&CPU14>; + + cluster1 { + core0 { + thread0 { + cpu = <&CPU12>; + }; + thread1 { + cpu = <&CPU13>; + }; }; - thread1 { - cpu = <&CPU15>; + core1 { + thread0 { + cpu = <&CPU14>; + }; + thread1 { + cpu = <&CPU15>; + }; }; }; }; @@ -473,3 +497,5 @@ cpus { =============================================================================== [1] ARM Linux kernel documentation Documentation/devicetree/bindings/arm/cpus.yaml +[2] Devicetree NUMA binding description + Documentation/devicetree/bindings/numa.txt