From patchwork Fri Jul 15 00:00:53 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Williams X-Patchwork-Id: 12918561 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 40DA0C433EF for ; Fri, 15 Jul 2022 00:00:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233194AbiGOAA5 (ORCPT ); Thu, 14 Jul 2022 20:00:57 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36338 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S241010AbiGOAA4 (ORCPT ); Thu, 14 Jul 2022 20:00:56 -0400 Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id C97A727FF3; Thu, 14 Jul 2022 17:00:54 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1657843254; x=1689379254; h=subject:from:to:cc:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=dtdJFh7kmK+xJYbCR5yQu8ImFrxaMhVVXsLFYvEJhPc=; b=PVjrtkjYQRwuqhgP3zm+BDEVjSIE/dR+XqL5vG0o1vlsT+q4PYpoWTNH jQJ+7FCJRH09ADr5MnKNkFb1kqchrQV8LTSh0bgBT8GaaND1XGunHclGy rqeg3EphngrspjM3YQoZmpW5Sl7cOLbtesuZWOSskHyoRD8flbiIRjeUF aZk/HwlnIBhweKLUXZTURVXkDDGVO0DLWjScG4Ah/r81Cc3C8Gr8WwIHQ i4KILTSR247myYsPXnvklfk+Vdc3JD5PZ8LiXkY0eWiMzlYXoOltlX8fE 41KkUHKYq+mhY2LQKYV/uuw4nIF5L54DR/O29G0X78LGaEk8s5FvuEnzv A==; X-IronPort-AV: E=McAfee;i="6400,9594,10408"; a="284417226" X-IronPort-AV: E=Sophos;i="5.92,272,1650956400"; d="scan'208";a="284417226" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Jul 2022 17:00:54 -0700 X-IronPort-AV: E=Sophos;i="5.92,272,1650956400"; d="scan'208";a="600309476" Received: from jlcone-mobl1.amr.corp.intel.com (HELO dwillia2-xfh.jf.intel.com) ([10.209.2.90]) by fmsmga007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 14 Jul 2022 17:00:53 -0700 Subject: [PATCH v2 02/28] cxl/core: Define a 'struct cxl_switch_decoder' From: Dan Williams To: linux-cxl@vger.kernel.org Cc: Ben Widawsky , hch@lst.de, nvdimm@lists.linux.dev, linux-pci@vger.kernel.org Date: Thu, 14 Jul 2022 17:00:53 -0700 Message-ID: <165784325340.1758207.5064717153608954960.stgit@dwillia2-xfh.jf.intel.com> In-Reply-To: <165784324066.1758207.15025479284039479071.stgit@dwillia2-xfh.jf.intel.com> References: <165784324066.1758207.15025479284039479071.stgit@dwillia2-xfh.jf.intel.com> User-Agent: StGit/0.18-3-g996c MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org Currently 'struct cxl_decoder' contains the superset of attributes needed for all decoder types. Before more type-specific attributes are added to the common definition, reorganize 'struct cxl_decoder' into type specific objects. This patch, the first of three, factors out a cxl_switch_decoder type. See the new kdoc for what a 'struct cxl_switch_decoder' represents in a CXL topology. Co-developed-by: Ben Widawsky Signed-off-by: Ben Widawsky Signed-off-by: Dan Williams Reviewed-by: Jonathan Cameron --- drivers/cxl/acpi.c | 4 + drivers/cxl/core/hdm.c | 33 +++++-- drivers/cxl/core/port.c | 188 ++++++++++++++++++++++++++++-------------- drivers/cxl/cxl.h | 30 +++++-- tools/testing/cxl/test/cxl.c | 23 ++++- 5 files changed, 189 insertions(+), 89 deletions(-) diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c index 541fc0b28b8f..62bf22ffb7aa 100644 --- a/drivers/cxl/acpi.c +++ b/drivers/cxl/acpi.c @@ -81,6 +81,7 @@ static int cxl_parse_cfmws(union acpi_subtable_headers *header, void *arg, int target_map[CXL_DECODER_MAX_INTERLEAVE]; struct cxl_cfmws_context *ctx = arg; struct cxl_port *root_port = ctx->root_port; + struct cxl_switch_decoder *cxlsd; struct device *dev = ctx->dev; struct acpi_cedt_cfmws *cfmws; struct cxl_decoder *cxld; @@ -106,10 +107,11 @@ static int cxl_parse_cfmws(union acpi_subtable_headers *header, void *arg, for (i = 0; i < ways; i++) target_map[i] = cfmws->interleave_targets[i]; - cxld = cxl_root_decoder_alloc(root_port, ways); + cxlsd = cxl_root_decoder_alloc(root_port, ways); if (IS_ERR(cxld)) return 0; + cxld = &cxlsd->cxld; cxld->flags = cfmws_to_decoder_flags(cfmws->restrictions); cxld->target_type = CXL_DECODER_EXPANDER; cxld->hpa_range = (struct range) { diff --git a/drivers/cxl/core/hdm.c b/drivers/cxl/core/hdm.c index c524e772fdae..2f10d42798de 100644 --- a/drivers/cxl/core/hdm.c +++ b/drivers/cxl/core/hdm.c @@ -49,20 +49,20 @@ static int add_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld, */ int devm_cxl_add_passthrough_decoder(struct cxl_port *port) { - struct cxl_decoder *cxld; + struct cxl_switch_decoder *cxlsd; struct cxl_dport *dport; int single_port_map[1]; - cxld = cxl_switch_decoder_alloc(port, 1); - if (IS_ERR(cxld)) - return PTR_ERR(cxld); + cxlsd = cxl_switch_decoder_alloc(port, 1); + if (IS_ERR(cxlsd)) + return PTR_ERR(cxlsd); device_lock_assert(&port->dev); dport = list_first_entry(&port->dports, typeof(*dport), list); single_port_map[0] = dport->port_id; - return add_hdm_decoder(port, cxld, single_port_map); + return add_hdm_decoder(port, &cxlsd->cxld, single_port_map); } EXPORT_SYMBOL_NS_GPL(devm_cxl_add_passthrough_decoder, CXL); @@ -255,14 +255,23 @@ int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm) int rc, target_count = cxlhdm->target_count; struct cxl_decoder *cxld; - if (is_cxl_endpoint(port)) + if (is_cxl_endpoint(port)) { cxld = cxl_endpoint_decoder_alloc(port); - else - cxld = cxl_switch_decoder_alloc(port, target_count); - if (IS_ERR(cxld)) { - dev_warn(&port->dev, - "Failed to allocate the decoder\n"); - return PTR_ERR(cxld); + if (IS_ERR(cxld)) { + dev_warn(&port->dev, + "Failed to allocate the decoder\n"); + return PTR_ERR(cxld); + } + } else { + struct cxl_switch_decoder *cxlsd; + + cxlsd = cxl_switch_decoder_alloc(port, target_count); + if (IS_ERR(cxlsd)) { + dev_warn(&port->dev, + "Failed to allocate the decoder\n"); + return PTR_ERR(cxlsd); + } + cxld = &cxlsd->cxld; } rc = init_hdm_decoder(port, cxld, target_map, hdm, i); diff --git a/drivers/cxl/core/port.c b/drivers/cxl/core/port.c index f62c0a6e17ea..27a2a6b839aa 100644 --- a/drivers/cxl/core/port.c +++ b/drivers/cxl/core/port.c @@ -120,20 +120,21 @@ static ssize_t target_type_show(struct device *dev, } static DEVICE_ATTR_RO(target_type); -static ssize_t emit_target_list(struct cxl_decoder *cxld, char *buf) +static ssize_t emit_target_list(struct cxl_switch_decoder *cxlsd, char *buf) { + struct cxl_decoder *cxld = &cxlsd->cxld; ssize_t offset = 0; int i, rc = 0; for (i = 0; i < cxld->interleave_ways; i++) { - struct cxl_dport *dport = cxld->target[i]; + struct cxl_dport *dport = cxlsd->target[i]; struct cxl_dport *next = NULL; if (!dport) break; if (i + 1 < cxld->interleave_ways) - next = cxld->target[i + 1]; + next = cxlsd->target[i + 1]; rc = sysfs_emit_at(buf, offset, "%d%s", dport->port_id, next ? "," : ""); if (rc < 0) @@ -144,18 +145,20 @@ static ssize_t emit_target_list(struct cxl_decoder *cxld, char *buf) return offset; } +static struct cxl_switch_decoder *to_cxl_switch_decoder(struct device *dev); + static ssize_t target_list_show(struct device *dev, struct device_attribute *attr, char *buf) { - struct cxl_decoder *cxld = to_cxl_decoder(dev); + struct cxl_switch_decoder *cxlsd = to_cxl_switch_decoder(dev); ssize_t offset; unsigned int seq; int rc; do { - seq = read_seqbegin(&cxld->target_lock); - rc = emit_target_list(cxld, buf); - } while (read_seqretry(&cxld->target_lock, seq)); + seq = read_seqbegin(&cxlsd->target_lock); + rc = emit_target_list(cxlsd, buf); + } while (read_seqretry(&cxlsd->target_lock, seq)); if (rc < 0) return rc; @@ -233,14 +236,28 @@ static const struct attribute_group *cxl_decoder_endpoint_attribute_groups[] = { NULL, }; +static void __cxl_decoder_release(struct cxl_decoder *cxld) +{ + struct cxl_port *port = to_cxl_port(cxld->dev.parent); + + ida_free(&port->decoder_ida, cxld->id); + put_device(&port->dev); +} + static void cxl_decoder_release(struct device *dev) { struct cxl_decoder *cxld = to_cxl_decoder(dev); - struct cxl_port *port = to_cxl_port(dev->parent); - ida_free(&port->decoder_ida, cxld->id); + __cxl_decoder_release(cxld); kfree(cxld); - put_device(&port->dev); +} + +static void cxl_switch_decoder_release(struct device *dev) +{ + struct cxl_switch_decoder *cxlsd = to_cxl_switch_decoder(dev); + + __cxl_decoder_release(&cxlsd->cxld); + kfree(cxlsd); } static const struct device_type cxl_decoder_endpoint_type = { @@ -251,13 +268,13 @@ static const struct device_type cxl_decoder_endpoint_type = { static const struct device_type cxl_decoder_switch_type = { .name = "cxl_decoder_switch", - .release = cxl_decoder_release, + .release = cxl_switch_decoder_release, .groups = cxl_decoder_switch_attribute_groups, }; static const struct device_type cxl_decoder_root_type = { .name = "cxl_decoder_root", - .release = cxl_decoder_release, + .release = cxl_switch_decoder_release, .groups = cxl_decoder_root_attribute_groups, }; @@ -272,15 +289,29 @@ bool is_root_decoder(struct device *dev) } EXPORT_SYMBOL_NS_GPL(is_root_decoder, CXL); +static bool is_switch_decoder(struct device *dev) +{ + return is_root_decoder(dev) || dev->type == &cxl_decoder_switch_type; +} + struct cxl_decoder *to_cxl_decoder(struct device *dev) { - if (dev_WARN_ONCE(dev, dev->type->release != cxl_decoder_release, + if (dev_WARN_ONCE(dev, + !is_switch_decoder(dev) && !is_endpoint_decoder(dev), "not a cxl_decoder device\n")) return NULL; return container_of(dev, struct cxl_decoder, dev); } EXPORT_SYMBOL_NS_GPL(to_cxl_decoder, CXL); +static struct cxl_switch_decoder *to_cxl_switch_decoder(struct device *dev) +{ + if (dev_WARN_ONCE(dev, !is_switch_decoder(dev), + "not a cxl_switch_decoder device\n")) + return NULL; + return container_of(dev, struct cxl_switch_decoder, cxld.dev); +} + static void cxl_ep_release(struct cxl_ep *ep) { if (!ep) @@ -1146,7 +1177,7 @@ struct cxl_dport *cxl_find_dport_by_dev(struct cxl_port *port, } EXPORT_SYMBOL_NS_GPL(cxl_find_dport_by_dev, CXL); -static int decoder_populate_targets(struct cxl_decoder *cxld, +static int decoder_populate_targets(struct cxl_switch_decoder *cxlsd, struct cxl_port *port, int *target_map) { int i, rc = 0; @@ -1159,17 +1190,17 @@ static int decoder_populate_targets(struct cxl_decoder *cxld, if (list_empty(&port->dports)) return -EINVAL; - write_seqlock(&cxld->target_lock); - for (i = 0; i < cxld->nr_targets; i++) { + write_seqlock(&cxlsd->target_lock); + for (i = 0; i < cxlsd->nr_targets; i++) { struct cxl_dport *dport = find_dport(port, target_map[i]); if (!dport) { rc = -ENXIO; break; } - cxld->target[i] = dport; + cxlsd->target[i] = dport; } - write_sequnlock(&cxld->target_lock); + write_sequnlock(&cxlsd->target_lock); return rc; } @@ -1177,56 +1208,34 @@ static int decoder_populate_targets(struct cxl_decoder *cxld, static struct lock_class_key cxl_decoder_key; /** - * cxl_decoder_alloc - Allocate a new CXL decoder + * cxl_decoder_alloc - Common decoder setup / initialization * @port: owning port of this decoder - * @nr_targets: downstream targets accessible by this decoder. All upstream - * ports and root ports must have at least 1 target. Endpoint - * devices will have 0 targets. Callers wishing to register an - * endpoint device should specify 0. - * - * A port should contain one or more decoders. Each of those decoders enable - * some address space for CXL.mem utilization. A decoder is expected to be - * configured by the caller before registering. + * @cxld: common decoder properties to initialize * - * Return: A new cxl decoder to be registered by cxl_decoder_add(). The decoder - * is initialized to be a "passthrough" decoder. + * A port may contain one or more decoders. Each of those decoders + * enable some address space for CXL.mem utilization. A decoder is + * expected to be configured by the caller before registering via + * cxl_decoder_add() */ -static struct cxl_decoder *cxl_decoder_alloc(struct cxl_port *port, - unsigned int nr_targets) +static int cxl_decoder_init(struct cxl_port *port, struct cxl_decoder *cxld) { - struct cxl_decoder *cxld; struct device *dev; - int rc = 0; - - if (nr_targets > CXL_DECODER_MAX_INTERLEAVE) - return ERR_PTR(-EINVAL); - - cxld = kzalloc(struct_size(cxld, target, nr_targets), GFP_KERNEL); - if (!cxld) - return ERR_PTR(-ENOMEM); + int rc; rc = ida_alloc(&port->decoder_ida, GFP_KERNEL); if (rc < 0) - goto err; + return rc; /* need parent to stick around to release the id */ get_device(&port->dev); cxld->id = rc; - cxld->nr_targets = nr_targets; - seqlock_init(&cxld->target_lock); dev = &cxld->dev; device_initialize(dev); lockdep_set_class(&dev->mutex, &cxl_decoder_key); device_set_pm_not_required(dev); dev->parent = &port->dev; dev->bus = &cxl_bus_type; - if (is_cxl_root(port)) - cxld->dev.type = &cxl_decoder_root_type; - else if (is_cxl_endpoint(port)) - cxld->dev.type = &cxl_decoder_endpoint_type; - else - cxld->dev.type = &cxl_decoder_switch_type; /* Pre initialize an "empty" decoder */ cxld->interleave_ways = 1; @@ -1237,10 +1246,19 @@ static struct cxl_decoder *cxl_decoder_alloc(struct cxl_port *port, .end = -1, }; - return cxld; -err: - kfree(cxld); - return ERR_PTR(rc); + return 0; +} + +static int cxl_switch_decoder_init(struct cxl_port *port, + struct cxl_switch_decoder *cxlsd, + int nr_targets) +{ + if (nr_targets > CXL_DECODER_MAX_INTERLEAVE) + return -EINVAL; + + cxlsd->nr_targets = nr_targets; + seqlock_init(&cxlsd->target_lock); + return cxl_decoder_init(port, &cxlsd->cxld); } /** @@ -1253,13 +1271,29 @@ static struct cxl_decoder *cxl_decoder_alloc(struct cxl_port *port, * firmware description of CXL resources into a CXL standard decode * topology. */ -struct cxl_decoder *cxl_root_decoder_alloc(struct cxl_port *port, - unsigned int nr_targets) +struct cxl_switch_decoder *cxl_root_decoder_alloc(struct cxl_port *port, + unsigned int nr_targets) { + struct cxl_switch_decoder *cxlsd; + struct cxl_decoder *cxld; + int rc; + if (!is_cxl_root(port)) return ERR_PTR(-EINVAL); - return cxl_decoder_alloc(port, nr_targets); + cxlsd = kzalloc(struct_size(cxlsd, target, nr_targets), GFP_KERNEL); + if (!cxlsd) + return ERR_PTR(-ENOMEM); + + rc = cxl_switch_decoder_init(port, cxlsd, nr_targets); + if (rc) { + kfree(cxlsd); + return ERR_PTR(rc); + } + + cxld = &cxlsd->cxld; + cxld->dev.type = &cxl_decoder_root_type; + return cxlsd; } EXPORT_SYMBOL_NS_GPL(cxl_root_decoder_alloc, CXL); @@ -1274,13 +1308,29 @@ EXPORT_SYMBOL_NS_GPL(cxl_root_decoder_alloc, CXL); * that sit between Switch Upstream Ports / Switch Downstream Ports and * Host Bridges / Root Ports. */ -struct cxl_decoder *cxl_switch_decoder_alloc(struct cxl_port *port, - unsigned int nr_targets) +struct cxl_switch_decoder *cxl_switch_decoder_alloc(struct cxl_port *port, + unsigned int nr_targets) { + struct cxl_switch_decoder *cxlsd; + struct cxl_decoder *cxld; + int rc; + if (is_cxl_root(port) || is_cxl_endpoint(port)) return ERR_PTR(-EINVAL); - return cxl_decoder_alloc(port, nr_targets); + cxlsd = kzalloc(struct_size(cxlsd, target, nr_targets), GFP_KERNEL); + if (!cxlsd) + return ERR_PTR(-ENOMEM); + + rc = cxl_switch_decoder_init(port, cxlsd, nr_targets); + if (rc) { + kfree(cxlsd); + return ERR_PTR(rc); + } + + cxld = &cxlsd->cxld; + cxld->dev.type = &cxl_decoder_switch_type; + return cxlsd; } EXPORT_SYMBOL_NS_GPL(cxl_switch_decoder_alloc, CXL); @@ -1292,10 +1342,24 @@ EXPORT_SYMBOL_NS_GPL(cxl_switch_decoder_alloc, CXL); */ struct cxl_decoder *cxl_endpoint_decoder_alloc(struct cxl_port *port) { + struct cxl_decoder *cxld; + int rc; + if (!is_cxl_endpoint(port)) return ERR_PTR(-EINVAL); - return cxl_decoder_alloc(port, 0); + cxld = kzalloc(sizeof(*cxld), GFP_KERNEL); + if (!cxld) + return ERR_PTR(-ENOMEM); + + rc = cxl_decoder_init(port, cxld); + if (rc) { + kfree(cxld); + return ERR_PTR(rc); + } + + cxld->dev.type = &cxl_decoder_endpoint_type; + return cxld; } EXPORT_SYMBOL_NS_GPL(cxl_endpoint_decoder_alloc, CXL); @@ -1337,7 +1401,9 @@ int cxl_decoder_add_locked(struct cxl_decoder *cxld, int *target_map) port = to_cxl_port(cxld->dev.parent); if (!is_endpoint_decoder(dev)) { - rc = decoder_populate_targets(cxld, port, target_map); + struct cxl_switch_decoder *cxlsd = to_cxl_switch_decoder(dev); + + rc = decoder_populate_targets(cxlsd, port, target_map); if (rc && (cxld->flags & CXL_DECODER_F_ENABLE)) { dev_err(&port->dev, "Failed to populate active decoder targets\n"); diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h index 570bd9f8141b..0289c06ec72c 100644 --- a/drivers/cxl/cxl.h +++ b/drivers/cxl/cxl.h @@ -220,7 +220,7 @@ enum cxl_decoder_type { #define CXL_DECODER_MAX_INTERLEAVE 16 /** - * struct cxl_decoder - CXL address range decode configuration + * struct cxl_decoder - Common CXL HDM Decoder Attributes * @dev: this decoder's device * @id: kernel device name id * @hpa_range: Host physical address range mapped by this decoder @@ -228,9 +228,6 @@ enum cxl_decoder_type { * @interleave_granularity: data stride per dport * @target_type: accelerator vs expander (type2 vs type3) selector * @flags: memory type capabilities and locking - * @target_lock: coordinate coherent reads of the target list - * @nr_targets: number of elements in @target - * @target: active ordered target list in current decoder configuration */ struct cxl_decoder { struct device dev; @@ -240,6 +237,23 @@ struct cxl_decoder { int interleave_granularity; enum cxl_decoder_type target_type; unsigned long flags; +}; + +/** + * struct cxl_switch_decoder - Switch specific CXL HDM Decoder + * @cxld: base cxl_decoder object + * @target_lock: coordinate coherent reads of the target list + * @nr_targets: number of elements in @target + * @target: active ordered target list in current decoder configuration + * + * The 'switch' decoder type represents the decoder instances of cxl_port's that + * route from the root of a CXL memory decode topology to the endpoints. They + * come in two flavors, root-level decoders, statically defined by platform + * firmware, and mid-level decoders, where interleave-granularity, + * interleave-width, and the target list are mutable. + */ +struct cxl_switch_decoder { + struct cxl_decoder cxld; seqlock_t target_lock; int nr_targets; struct cxl_dport *target[]; @@ -364,10 +378,10 @@ struct cxl_dport *cxl_find_dport_by_dev(struct cxl_port *port, struct cxl_decoder *to_cxl_decoder(struct device *dev); bool is_root_decoder(struct device *dev); bool is_endpoint_decoder(struct device *dev); -struct cxl_decoder *cxl_root_decoder_alloc(struct cxl_port *port, - unsigned int nr_targets); -struct cxl_decoder *cxl_switch_decoder_alloc(struct cxl_port *port, - unsigned int nr_targets); +struct cxl_switch_decoder *cxl_root_decoder_alloc(struct cxl_port *port, + unsigned int nr_targets); +struct cxl_switch_decoder *cxl_switch_decoder_alloc(struct cxl_port *port, + unsigned int nr_targets); int cxl_decoder_add(struct cxl_decoder *cxld, int *target_map); struct cxl_decoder *cxl_endpoint_decoder_alloc(struct cxl_port *port); int cxl_decoder_add_locked(struct cxl_decoder *cxld, int *target_map); diff --git a/tools/testing/cxl/test/cxl.c b/tools/testing/cxl/test/cxl.c index 6e086fbc5c5b..7991ddc6e562 100644 --- a/tools/testing/cxl/test/cxl.c +++ b/tools/testing/cxl/test/cxl.c @@ -451,14 +451,23 @@ static int mock_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm) struct cxl_decoder *cxld; int rc; - if (target_count) - cxld = cxl_switch_decoder_alloc(port, target_count); - else + if (target_count) { + struct cxl_switch_decoder *cxlsd; + + cxlsd = cxl_switch_decoder_alloc(port, target_count); + if (IS_ERR(cxlsd)) { + dev_warn(&port->dev, + "Failed to allocate the decoder\n"); + return PTR_ERR(cxlsd); + } + cxld = &cxlsd->cxld; + } else { cxld = cxl_endpoint_decoder_alloc(port); - if (IS_ERR(cxld)) { - dev_warn(&port->dev, - "Failed to allocate the decoder\n"); - return PTR_ERR(cxld); + if (IS_ERR(cxld)) { + dev_warn(&port->dev, + "Failed to allocate the decoder\n"); + return PTR_ERR(cxld); + } } cxld->hpa_range = (struct range) {