From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D0DE6C433F5 for ; Fri, 29 Oct 2021 22:03:01 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ADBCD60187 for ; Fri, 29 Oct 2021 22:03:01 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231391AbhJ2WFa (ORCPT ); Fri, 29 Oct 2021 18:05:30 -0400 Received: from mga07.intel.com ([134.134.136.100]:60525 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231173AbhJ2WF3 (ORCPT ); Fri, 29 Oct 2021 18:05:29 -0400 X-IronPort-AV: E=McAfee;i="6200,9189,10152"; a="294222595" X-IronPort-AV: E=Sophos;i="5.87,193,1631602800"; d="scan'208";a="294222595" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Oct 2021 15:03:00 -0700 X-IronPort-AV: E=Sophos;i="5.87,193,1631602800"; d="scan'208";a="448264898" Received: from applebex-mobl2.amr.corp.intel.com (HELO intel.com) ([10.252.137.25]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 29 Oct 2021 15:03:00 -0700 Date: Fri, 29 Oct 2021 15:02:58 -0700 From: Ben Widawsky To: Dan Williams Cc: linux-cxl@vger.kernel.org, Chet Douglas , Alison Schofield , Ira Weiny , Jonathan Cameron , Vishal Verma Subject: Re: [RFC PATCH v2 06/28] cxl: Introduce endpoint decoders Message-ID: <20211029220258.ghqdgnehg6ptjy3e@intel.com> References: <20211022183709.1199701-1-ben.widawsky@intel.com> <20211022183709.1199701-7-ben.widawsky@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-cxl@vger.kernel.org On 21-10-29 14:00:21, Dan Williams wrote: > On Fri, Oct 22, 2021 at 11:37 AM Ben Widawsky wrote: > > > > Endpoints have decoders too. It is useful to share the same > > infrastructure from cxl_core. Endpoints do not have dports (downstream > > targets), only the underlying physical medium. As a result, some special > > casing is needed. > > > > There is no functional change introduced yet as endpoints don't actually > > enumerate decoders yet. > > The nr_targets type change either needs to be commented on here, or > moved to its own patch. Do you have a preference? > > Otherwise, this looks good. > > > > > Signed-off-by: Ben Widawsky > > --- > > drivers/cxl/core/bus.c | 40 ++++++++++++++++++++++++++++++++-------- > > drivers/cxl/cxl.h | 3 ++- > > 2 files changed, 34 insertions(+), 9 deletions(-) > > > > diff --git a/drivers/cxl/core/bus.c b/drivers/cxl/core/bus.c > > index 454d4d846eb2..5564a71773e2 100644 > > --- a/drivers/cxl/core/bus.c > > +++ b/drivers/cxl/core/bus.c > > @@ -175,6 +175,12 @@ static const struct attribute_group *cxl_decoder_switch_attribute_groups[] = { > > NULL, > > }; > > > > +static const struct attribute_group *cxl_decoder_endpoint_attribute_groups[] = { > > + &cxl_decoder_base_attribute_group, > > + &cxl_base_attribute_group, > > + NULL, > > +}; > > + > > static void cxl_decoder_release(struct device *dev) > > { > > struct cxl_decoder *cxld = to_cxl_decoder(dev); > > @@ -184,6 +190,12 @@ static void cxl_decoder_release(struct device *dev) > > kfree(cxld); > > } > > > > +static const struct device_type cxl_decoder_endpoint_type = { > > + .name = "cxl_decoder_endpoint", > > + .release = cxl_decoder_release, > > + .groups = cxl_decoder_endpoint_attribute_groups, > > +}; > > + > > static const struct device_type cxl_decoder_switch_type = { > > .name = "cxl_decoder_switch", > > .release = cxl_decoder_release, > > @@ -196,6 +208,11 @@ static const struct device_type cxl_decoder_root_type = { > > .groups = cxl_decoder_root_attribute_groups, > > }; > > > > +static bool is_endpoint_decoder(struct device *dev) > > +{ > > + return dev->type == &cxl_decoder_endpoint_type; > > +} > > + > > bool is_root_decoder(struct device *dev) > > { > > return dev->type == &cxl_decoder_root_type; > > @@ -483,7 +500,8 @@ static int decoder_populate_targets(struct cxl_decoder *cxld, > > return rc; > > } > > > > -struct cxl_decoder *cxl_decoder_alloc(struct cxl_port *port, int nr_targets) > > +struct cxl_decoder *cxl_decoder_alloc(struct cxl_port *port, > > + unsigned int nr_targets) > > { > > struct cxl_decoder *cxld, cxld_const_init = { > > .nr_targets = nr_targets, > > @@ -491,7 +509,7 @@ struct cxl_decoder *cxl_decoder_alloc(struct cxl_port *port, int nr_targets) > > struct device *dev; > > int rc = 0; > > > > - if (nr_targets > CXL_DECODER_MAX_INTERLEAVE || nr_targets < 1) > > + if (nr_targets > CXL_DECODER_MAX_INTERLEAVE) > > return ERR_PTR(-EINVAL); > > > > cxld = kzalloc(struct_size(cxld, target, nr_targets), GFP_KERNEL); > > @@ -510,8 +528,11 @@ struct cxl_decoder *cxl_decoder_alloc(struct cxl_port *port, int nr_targets) > > dev->parent = &port->dev; > > dev->bus = &cxl_bus_type; > > > > + /* Endpoints don't have a target list */ > > + if (nr_targets == 0) > > + dev->type = &cxl_decoder_endpoint_type; > > /* root ports do not have a cxl_port_type parent */ > > - if (port->dev.parent->type == &cxl_port_type) > > + else if (port->dev.parent->type == &cxl_port_type) > > dev->type = &cxl_decoder_switch_type; > > else > > dev->type = &cxl_decoder_root_type; > > @@ -538,12 +559,15 @@ int cxl_decoder_add(struct cxl_decoder *cxld, int *target_map) > > if (cxld->interleave_ways < 1) > > return -EINVAL; > > > > - port = to_cxl_port(cxld->dev.parent); > > - rc = decoder_populate_targets(cxld, port, target_map); > > - if (rc) > > - return rc; > > - > > dev = &cxld->dev; > > + > > + port = to_cxl_port(cxld->dev.parent); > > + if (!is_endpoint_decoder(dev)) { > > + rc = decoder_populate_targets(cxld, port, target_map); > > + if (rc) > > + return rc; > > + } > > + > > rc = dev_set_name(dev, "decoder%d.%d", port->id, cxld->id); > > if (rc) > > return rc; > > diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h > > index 7f2e2bdc7883..91b8fd54bc93 100644 > > --- a/drivers/cxl/cxl.h > > +++ b/drivers/cxl/cxl.h > > @@ -293,7 +293,8 @@ int cxl_add_dport(struct cxl_port *port, struct device *dport, int port_id, > > > > struct cxl_decoder *to_cxl_decoder(struct device *dev); > > bool is_root_decoder(struct device *dev); > > -struct cxl_decoder *cxl_decoder_alloc(struct cxl_port *port, int nr_targets); > > +struct cxl_decoder *cxl_decoder_alloc(struct cxl_port *port, > > + unsigned int nr_targets); > > int cxl_decoder_add(struct cxl_decoder *cxld, int *target_map); > > int cxl_decoder_autoremove(struct device *host, struct cxl_decoder *cxld); > > > > -- > > 2.33.1 > >