From nobody Tue Dec 2 02:43:33 2025 Received: from mailout1.samsung.com (mailout1.samsung.com [203.254.224.24]) (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 99E9832E75F for ; Wed, 19 Nov 2025 07:53:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=203.254.224.24 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763538811; cv=none; b=aAx0xItC8TTjQhQXi5jeHzPwspOwsiVtxl5xGUylXkXjG19pct/u5gd0jxLAnlINy/1mJxsf+/TIe2gJE57EDs5Qt4nWan7QFF3WWkwLSZbhGPqBD84jvIgV+2ri1oSmueic1b3AFpvzua/hUIVF3BVBeguV36DrZsmmUyiPfN4= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1763538811; c=relaxed/simple; bh=rCnFs+wTFiUzB8dwDWhtT0JfRAiF5oUhvonJGQ9Bzws=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:MIME-Version: Content-Type:References; b=kAE6484AhWAmbq4DyrU3PYaSbRUfC+fg6SGCHdqmIqJEB8y1Od9mrBp33w3TCSnMpEUc+3wy2F7UE84l4c/0xEo/lXH2MyCFYDzwrid060ctmrUyfVE/7UZKI9LGD+I5/jeiZi0NhQQwdJZzaS6etnvtPCpuIuePGK3bRYoGxNk= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=samsung.com; spf=pass smtp.mailfrom=samsung.com; dkim=pass (1024-bit key) header.d=samsung.com header.i=@samsung.com header.b=kcxQOhVH; arc=none smtp.client-ip=203.254.224.24 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=samsung.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=samsung.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=samsung.com header.i=@samsung.com header.b="kcxQOhVH" Received: from epcas5p2.samsung.com (unknown [182.195.41.40]) by mailout1.samsung.com (KnoxPortal) with ESMTP id 20251119075326epoutp014c2035fd1eee6a40ef85688f05af588f~5WTODJJeo3132231322epoutp01i for ; Wed, 19 Nov 2025 07:53:26 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 mailout1.samsung.com 20251119075326epoutp014c2035fd1eee6a40ef85688f05af588f~5WTODJJeo3132231322epoutp01i DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=samsung.com; s=mail20170921; t=1763538806; bh=g71o0PINWhr1xwvhb/lFkayQCIafgmrL7rI+AkDSi7E=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=kcxQOhVHa47TnJY+YHN7pj27wim8+CxB7jx4XkViN5n9OFmvcb5hbpHuegJ2NaL9E Os3RNWKotjnnD/+Dnw8Ya6zESI4G8x5SZETc0d0fcvt8WKOgWxSg+K34G0EyLvAVOX hvYTfXk50VqkILDocCQ7dwqvJtyJjbJbEZx/O8Oo= Received: from epsnrtp04.localdomain (unknown [182.195.42.156]) by epcas5p3.samsung.com (KnoxPortal) with ESMTPS id 20251119075326epcas5p3c6a45700cffb798e2a79999acc8b4137~5WTNvkL3a0829208292epcas5p3B; Wed, 19 Nov 2025 07:53:26 +0000 (GMT) Received: from epcas5p4.samsung.com (unknown [182.195.38.89]) by epsnrtp04.localdomain (Postfix) with ESMTP id 4dBDHn39xNz6B9m8; Wed, 19 Nov 2025 07:53:25 +0000 (GMT) Received: from epsmtip1.samsung.com (unknown [182.195.34.30]) by epcas5p1.samsung.com (KnoxPortal) with ESMTPA id 20251119075324epcas5p1b0a7149ede962491e6be2d72d33f77eb~5WTMOZS7o1599915999epcas5p1a; Wed, 19 Nov 2025 07:53:24 +0000 (GMT) Received: from test-PowerEdge-R740xd.samsungds.net (unknown [107.99.41.79]) by epsmtip1.samsung.com (KnoxPortal) with ESMTPA id 20251119075323epsmtip1298d30dc1c8595c3634129f813fc0c23~5WTLHh0VD2604526045epsmtip1Y; Wed, 19 Nov 2025 07:53:23 +0000 (GMT) From: Neeraj Kumar To: linux-cxl@vger.kernel.org, nvdimm@lists.linux.dev, linux-kernel@vger.kernel.org, gost.dev@samsung.com Cc: a.manzanares@samsung.com, vishak.g@samsung.com, neeraj.kernel@gmail.com, Neeraj Kumar Subject: [PATCH V4 10/17] cxl/mem: Refactor cxl pmem region auto-assembling Date: Wed, 19 Nov 2025 13:22:48 +0530 Message-Id: <20251119075255.2637388-11-s.neeraj@samsung.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20251119075255.2637388-1-s.neeraj@samsung.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-CMS-MailID: 20251119075324epcas5p1b0a7149ede962491e6be2d72d33f77eb X-Msg-Generator: CA Content-Type: text/plain; charset="utf-8" CMS-TYPE: 105P cpgsPolicy: CPGSC10-542,Y X-CFilter-Loop: Reflected X-CMS-RootMailID: 20251119075324epcas5p1b0a7149ede962491e6be2d72d33f77eb References: <20251119075255.2637388-1-s.neeraj@samsung.com> In 84ec985944ef3, devm_cxl_add_nvdimm() sequence was changed and called before devm_cxl_add_endpoint(). It's because cxl pmem region auto-assembly used to get called at last in cxl_endpoint_port_probe(), which requires cxl_nvd presence. For cxl region persistency, region creation happens during nvdimm_probe which need the completion of endpoint probe. In order to accommodate both cxl pmem region auto-assembly and cxl region persistency, refactored following 1. Re-Sequence devm_cxl_add_nvdimm() after devm_cxl_add_endpoint(). This will be called only after successful completion of endpoint probe. 2. Create cxl_region_discovery() which performs pmem region auto-assembly and remove cxl pmem region auto-assembly from cxl_endpoint_port_probe() 3. Register cxl_region_discovery() with devm_cxl_add_memdev() which gets called during cxl_pci_probe() in context of cxl_mem_probe() 4. As cxlmd->ops->probe() calls registered cxl_region_discovery(), so move devm_cxl_add_nvdimm() before cxlmd->ops->probe(). It gurantees both the completion of endpoint probe and cxl_nvd presence before calling cxlmd->ops->probe(). Signed-off-by: Neeraj Kumar Reviewed-by: Dave Jiang --- drivers/cxl/core/region.c | 37 +++++++++++++++++++++++++++++++++++++ drivers/cxl/cxl.h | 5 +++++ drivers/cxl/mem.c | 18 +++++++++--------- drivers/cxl/pci.c | 4 +++- drivers/cxl/port.c | 39 +-------------------------------------- 5 files changed, 55 insertions(+), 48 deletions(-) diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c index 2cf5b29cefd2..3c868c4de4ec 100644 --- a/drivers/cxl/core/region.c +++ b/drivers/cxl/core/region.c @@ -3724,6 +3724,43 @@ int cxl_add_to_region(struct cxl_endpoint_decoder *c= xled) } EXPORT_SYMBOL_NS_GPL(cxl_add_to_region, "CXL"); =20 +static int discover_region(struct device *dev, void *unused) +{ + struct cxl_endpoint_decoder *cxled; + int rc; + + if (!is_endpoint_decoder(dev)) + return 0; + + cxled =3D to_cxl_endpoint_decoder(dev); + if ((cxled->cxld.flags & CXL_DECODER_F_ENABLE) =3D=3D 0) + return 0; + + if (cxled->state !=3D CXL_DECODER_STATE_AUTO) + return 0; + + /* + * Region enumeration is opportunistic, if this add-event fails, + * continue to the next endpoint decoder. + */ + rc =3D cxl_add_to_region(cxled); + if (rc) + dev_dbg(dev, "failed to add to region: %#llx-%#llx\n", + cxled->cxld.hpa_range.start, cxled->cxld.hpa_range.end); + + return 0; +} + +int cxl_region_discovery(struct cxl_memdev *cxlmd) +{ + struct cxl_port *port =3D cxlmd->endpoint; + + device_for_each_child(&port->dev, NULL, discover_region); + + return 0; +} +EXPORT_SYMBOL_NS_GPL(cxl_region_discovery, "CXL"); + u64 cxl_port_get_spa_cache_alias(struct cxl_port *endpoint, u64 spa) { struct cxl_region_ref *iter; diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h index ba17fa86d249..684a0d1b441a 100644 --- a/drivers/cxl/cxl.h +++ b/drivers/cxl/cxl.h @@ -904,6 +904,7 @@ struct cxl_pmem_region *to_cxl_pmem_region(struct devic= e *dev); int cxl_add_to_region(struct cxl_endpoint_decoder *cxled); struct cxl_dax_region *to_cxl_dax_region(struct device *dev); u64 cxl_port_get_spa_cache_alias(struct cxl_port *endpoint, u64 spa); +int cxl_region_discovery(struct cxl_memdev *cxlmd); #else static inline bool is_cxl_pmem_region(struct device *dev) { @@ -926,6 +927,10 @@ static inline u64 cxl_port_get_spa_cache_alias(struct = cxl_port *endpoint, { return 0; } +static inline int cxl_region_discovery(struct cxl_memdev *cxlmd) +{ + return 0; +} #endif =20 void cxl_endpoint_parse_cdat(struct cxl_port *port); diff --git a/drivers/cxl/mem.c b/drivers/cxl/mem.c index 13d9e089ecaf..f5e3e2fca86c 100644 --- a/drivers/cxl/mem.c +++ b/drivers/cxl/mem.c @@ -115,15 +115,6 @@ static int cxl_mem_probe(struct device *dev) return -ENXIO; } =20 - if (cxl_pmem_size(cxlds) && IS_ENABLED(CONFIG_CXL_PMEM)) { - rc =3D devm_cxl_add_nvdimm(parent_port, cxlmd); - if (rc) { - if (rc =3D=3D -ENODEV) - dev_info(dev, "PMEM disabled by platform\n"); - return rc; - } - } - if (dport->rch) endpoint_parent =3D parent_port->uport_dev; else @@ -143,6 +134,15 @@ static int cxl_mem_probe(struct device *dev) return rc; } =20 + if (cxl_pmem_size(cxlds) && IS_ENABLED(CONFIG_CXL_PMEM)) { + rc =3D devm_cxl_add_nvdimm(parent_port, cxlmd); + if (rc) { + if (rc =3D=3D -ENODEV) + dev_info(dev, "PMEM disabled by platform\n"); + return rc; + } + } + if (cxlmd->ops) { rc =3D cxlmd->ops->probe(cxlmd); if (rc) diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c index e21051d79b25..d56fdfe4b43b 100644 --- a/drivers/cxl/pci.c +++ b/drivers/cxl/pci.c @@ -907,6 +907,7 @@ static int cxl_pci_probe(struct pci_dev *pdev, const st= ruct pci_device_id *id) struct cxl_memdev_state *mds; struct cxl_dev_state *cxlds; struct cxl_register_map map; + struct cxl_memdev_ops ops; struct cxl_memdev *cxlmd; int rc, pmu_count; unsigned int i; @@ -1006,7 +1007,8 @@ static int cxl_pci_probe(struct pci_dev *pdev, const = struct pci_device_id *id) if (rc) dev_dbg(&pdev->dev, "No CXL Features discovered\n"); =20 - cxlmd =3D devm_cxl_add_memdev(&pdev->dev, cxlds, NULL); + ops.probe =3D cxl_region_discovery; + cxlmd =3D devm_cxl_add_memdev(&pdev->dev, cxlds, &ops); if (IS_ERR(cxlmd)) return PTR_ERR(cxlmd); =20 diff --git a/drivers/cxl/port.c b/drivers/cxl/port.c index d5fd0c5ae49b..ad98b2881fed 100644 --- a/drivers/cxl/port.c +++ b/drivers/cxl/port.c @@ -31,33 +31,6 @@ static void schedule_detach(void *cxlmd) schedule_cxl_memdev_detach(cxlmd); } =20 -static int discover_region(struct device *dev, void *unused) -{ - struct cxl_endpoint_decoder *cxled; - int rc; - - if (!is_endpoint_decoder(dev)) - return 0; - - cxled =3D to_cxl_endpoint_decoder(dev); - if ((cxled->cxld.flags & CXL_DECODER_F_ENABLE) =3D=3D 0) - return 0; - - if (cxled->state !=3D CXL_DECODER_STATE_AUTO) - return 0; - - /* - * Region enumeration is opportunistic, if this add-event fails, - * continue to the next endpoint decoder. - */ - rc =3D cxl_add_to_region(cxled); - if (rc) - dev_dbg(dev, "failed to add to region: %#llx-%#llx\n", - cxled->cxld.hpa_range.start, cxled->cxld.hpa_range.end); - - return 0; -} - static int cxl_switch_port_probe(struct cxl_port *port) { /* Reset nr_dports for rebind of driver */ @@ -83,17 +56,7 @@ static int cxl_endpoint_port_probe(struct cxl_port *port) if (rc) return rc; =20 - rc =3D devm_cxl_endpoint_decoders_setup(port); - if (rc) - return rc; - - /* - * Now that all endpoint decoders are successfully enumerated, try to - * assemble regions from committed decoders - */ - device_for_each_child(&port->dev, NULL, discover_region); - - return 0; + return devm_cxl_endpoint_decoders_setup(port); } =20 static int cxl_port_probe(struct device *dev) --=20 2.34.1