From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F1EF2602F for ; Wed, 20 Jul 2022 17:29:48 +0000 (UTC) Received: from fraeml706-chm.china.huawei.com (unknown [172.18.147.200]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4Lp2hw1yRjz67ms2; Thu, 21 Jul 2022 01:28:00 +0800 (CST) Received: from lhreml710-chm.china.huawei.com (10.201.108.61) by fraeml706-chm.china.huawei.com (10.206.15.55) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256_P256) id 15.1.2375.24; Wed, 20 Jul 2022 19:29:45 +0200 Received: from localhost (10.81.205.121) by lhreml710-chm.china.huawei.com (10.201.108.61) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2375.24; Wed, 20 Jul 2022 18:29:45 +0100 Date: Wed, 20 Jul 2022 18:29:41 +0100 From: Jonathan Cameron To: Dan Williams CC: , Ben Widawsky , , , Subject: Re: [PATCH v2 23/28] cxl/region: Attach endpoint decoders Message-ID: <20220720182941.00004300@Huawei.com> In-Reply-To: <165784337277.1758207.4108508181328528703.stgit@dwillia2-xfh.jf.intel.com> References: <165784324066.1758207.15025479284039479071.stgit@dwillia2-xfh.jf.intel.com> <165784337277.1758207.4108508181328528703.stgit@dwillia2-xfh.jf.intel.com> Organization: Huawei Technologies Research and Development (UK) Ltd. X-Mailer: Claws Mail 4.0.0 (GTK+ 3.24.29; i686-w64-mingw32) Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.81.205.121] X-ClientProxiedBy: lhreml754-chm.china.huawei.com (10.201.108.204) To lhreml710-chm.china.huawei.com (10.201.108.61) X-CFilter-Loop: Reflected On Thu, 14 Jul 2022 17:02:52 -0700 Dan Williams wrote: > CXL regions (interleave sets) are made up of a set of memory devices > where each device maps a portion of the interleave with one of its > decoders (see CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure). > As endpoint decoders are identified by a provisioning tool they can be > added to a region provided the region interleave properties are set > (way, granularity, HPA) and DPA has been assigned to the decoder. > > The attach event triggers several validation checks, for example: > - is the DPA sized appropriately for the region > - is the decoder reachable via the host-bridges identified by the > region's root decoder > - is the device already active in a different region position slot > - are there already regions with a higher HPA active on a given port > (per CXL 2.0 8.2.5.12.20 Committing Decoder Programming) > > ...and the attach event affords an opportunity to collect data and > resources relevant to later programming the target lists in switch > decoders, for example: > - allocate a decoder at each cxl_port in the decode chain > - for a given switch port, how many the region's endpoints are hosted > through the port > - how many unique targets (next hops) does a port need to map to reach > those endpoints > > The act of reconciling this information and deploying it to the decoder > configuration is saved for a follow-on patch. > > Co-developed-by: Ben Widawsky > Signed-off-by: Ben Widawsky > Signed-off-by: Dan Williams All the review comment resolutions from v1 look good to me. Reviewed-by: Jonathan Cameron Thanks, Jonathan