13 files changed, 989 insertions, 725 deletions

diff --git a/drivers/cxl/Makefile b/drivers/cxl/Makefile
index 32954059b37b..d1aaabc940f3 100644
--- a/drivers/cxl/Makefile
+++ b/drivers/cxl/Makefile
@@ -1,11 +1,9 @@
 # SPDX-License-Identifier: GPL-2.0
-obj-$(CONFIG_CXL_BUS) += cxl_core.o
+obj-$(CONFIG_CXL_BUS) += core/
 obj-$(CONFIG_CXL_MEM) += cxl_pci.o
 obj-$(CONFIG_CXL_ACPI) += cxl_acpi.o
 obj-$(CONFIG_CXL_PMEM) += cxl_pmem.o
 
-ccflags-y += -DDEFAULT_SYMBOL_NAMESPACE=CXL
-cxl_core-y := core.o
 cxl_pci-y := pci.o
 cxl_acpi-y := acpi.o
 cxl_pmem-y := pmem.o
diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c
index 8ae89273f58e..54e9d4d2cf5f 100644
--- a/drivers/cxl/acpi.c
+++ b/drivers/cxl/acpi.c
@@ -243,6 +243,9 @@ static struct acpi_device *to_cxl_host_bridge(struct device *dev)
 {
 	struct acpi_device *adev = to_acpi_device(dev);
 
+	if (!acpi_pci_find_root(adev->handle))
+		return NULL;
+
 	if (strcmp(acpi_device_hid(adev), "ACPI0016") == 0)
 		return adev;
 	return NULL;
@@ -266,10 +269,6 @@ static int add_host_bridge_uport(struct device *match, void *arg)
 	if (!bridge)
 		return 0;
 
-	pci_root = acpi_pci_find_root(bridge->handle);
-	if (!pci_root)
-		return -ENXIO;
-
 	dport = find_dport_by_dev(root_port, match);
 	if (!dport) {
 		dev_dbg(host, "host bridge expected and not found\n");
@@ -282,6 +281,11 @@ static int add_host_bridge_uport(struct device *match, void *arg)
 		return PTR_ERR(port);
 	dev_dbg(host, "%s: add: %s\n", dev_name(match), dev_name(&port->dev));
 
+	/*
+	 * Note that this lookup already succeeded in
+	 * to_cxl_host_bridge(), so no need to check for failure here
+	 */
+	pci_root = acpi_pci_find_root(bridge->handle);
 	ctx = (struct cxl_walk_context){
 		.dev = host,
 		.root = pci_root->bus,
diff --git a/drivers/cxl/core/Makefile b/drivers/cxl/core/Makefile
new file mode 100644
index 000000000000..0fdbf3c6ac1a
--- /dev/null
+++ b/drivers/cxl/core/Makefile
@@ -0,0 +1,8 @@
+# SPDX-License-Identifier: GPL-2.0
+obj-$(CONFIG_CXL_BUS) += cxl_core.o
+
+ccflags-y += -DDEFAULT_SYMBOL_NAMESPACE=CXL -I$(srctree)/drivers/cxl
+cxl_core-y := bus.o
+cxl_core-y += pmem.o
+cxl_core-y += regs.o
+cxl_core-y += memdev.o
diff --git a/drivers/cxl/core.c b/drivers/cxl/core/bus.c
index a2e4d54fc7bc..267d8042bec2 100644
--- a/drivers/cxl/core.c
+++ b/drivers/cxl/core/bus.c
@@ -6,14 +6,22 @@
 #include <linux/pci.h>
 #include <linux/slab.h>
 #include <linux/idr.h>
-#include "cxl.h"
-#include "mem.h"
+#include <cxlmem.h>
+#include <cxl.h>
+#include "core.h"
 
 /**
  * DOC: cxl core
  *
- * The CXL core provides a sysfs hierarchy for control devices and a rendezvous
- * point for cross-device interleave coordination through cxl ports.
+ * The CXL core provides a set of interfaces that can be consumed by CXL aware
+ * drivers. The interfaces allow for creation, modification, and destruction of
+ * regions, memory devices, ports, and decoders. CXL aware drivers must register
+ * with the CXL core via these interfaces in order to be able to participate in
+ * cross-device interleave coordination. The CXL core also establishes and
+ * maintains the bridge to the nvdimm subsystem.
+ *
+ * CXL core introduces sysfs hierarchy to control the devices that are
+ * instantiated by the core.
  */
 
 static DEFINE_IDA(cxl_port_ida);
@@ -30,7 +38,7 @@ static struct attribute *cxl_base_attributes[] = {
 	NULL,
 };
 
-static struct attribute_group cxl_base_attribute_group = {
+struct attribute_group cxl_base_attribute_group = {
 	.attrs = cxl_base_attributes,
 };
 
@@ -507,11 +515,6 @@ err:
 	return ERR_PTR(rc);
 }
 
-static void unregister_dev(void *dev)
-{
-	device_unregister(dev);
-}
-
 struct cxl_decoder *
 devm_cxl_add_decoder(struct device *host, struct cxl_port *port, int nr_targets,
 		     resource_size_t base, resource_size_t len,
@@ -536,7 +539,7 @@ devm_cxl_add_decoder(struct device *host, struct cxl_port *port, int nr_targets,
 	if (rc)
 		goto err;
 
-	rc = devm_add_action_or_reset(host, unregister_dev, dev);
+	rc = devm_add_action_or_reset(host, unregister_cxl_dev, dev);
 	if (rc)
 		return ERR_PTR(rc);
 	return cxld;
@@ -548,429 +551,6 @@ err:
 EXPORT_SYMBOL_GPL(devm_cxl_add_decoder);
 
 /**
- * cxl_probe_component_regs() - Detect CXL Component register blocks
- * @dev: Host device of the @base mapping
- * @base: Mapping containing the HDM Decoder Capability Header
- * @map: Map object describing the register block information found
- *
- * See CXL 2.0 8.2.4 Component Register Layout and Definition
- * See CXL 2.0 8.2.5.5 CXL Device Register Interface
- *
- * Probe for component register information and return it in map object.
- */
-void cxl_probe_component_regs(struct device *dev, void __iomem *base,
-			      struct cxl_component_reg_map *map)
-{
-	int cap, cap_count;
-	u64 cap_array;
-
-	*map = (struct cxl_component_reg_map) { 0 };
-
-	/*
-	 * CXL.cache and CXL.mem registers are at offset 0x1000 as defined in
-	 * CXL 2.0 8.2.4 Table 141.
-	 */
-	base += CXL_CM_OFFSET;
-
-	cap_array = readq(base + CXL_CM_CAP_HDR_OFFSET);
-
-	if (FIELD_GET(CXL_CM_CAP_HDR_ID_MASK, cap_array) != CM_CAP_HDR_CAP_ID) {
-		dev_err(dev,
-			"Couldn't locate the CXL.cache and CXL.mem capability array header./n");
-		return;
-	}
-
-	/* It's assumed that future versions will be backward compatible */
-	cap_count = FIELD_GET(CXL_CM_CAP_HDR_ARRAY_SIZE_MASK, cap_array);
-
-	for (cap = 1; cap <= cap_count; cap++) {
-		void __iomem *register_block;
-		u32 hdr;
-		int decoder_cnt;
-		u16 cap_id, offset;
-		u32 length;
-
-		hdr = readl(base + cap * 0x4);
-
-		cap_id = FIELD_GET(CXL_CM_CAP_HDR_ID_MASK, hdr);
-		offset = FIELD_GET(CXL_CM_CAP_PTR_MASK, hdr);
-		register_block = base + offset;
-
-		switch (cap_id) {
-		case CXL_CM_CAP_CAP_ID_HDM:
-			dev_dbg(dev, "found HDM decoder capability (0x%x)\n",
-				offset);
-
-			hdr = readl(register_block);
-
-			decoder_cnt = cxl_hdm_decoder_count(hdr);
-			length = 0x20 * decoder_cnt + 0x10;
-
-			map->hdm_decoder.valid = true;
-			map->hdm_decoder.offset = CXL_CM_OFFSET + offset;
-			map->hdm_decoder.size = length;
-			break;
-		default:
-			dev_dbg(dev, "Unknown CM cap ID: %d (0x%x)\n", cap_id,
-				offset);
-			break;
-		}
-	}
-}
-EXPORT_SYMBOL_GPL(cxl_probe_component_regs);
-
-static void cxl_nvdimm_bridge_release(struct device *dev)
-{
-	struct cxl_nvdimm_bridge *cxl_nvb = to_cxl_nvdimm_bridge(dev);
-
-	kfree(cxl_nvb);
-}
-
-static const struct attribute_group *cxl_nvdimm_bridge_attribute_groups[] = {
-	&cxl_base_attribute_group,
-	NULL,
-};
-
-static const struct device_type cxl_nvdimm_bridge_type = {
-	.name = "cxl_nvdimm_bridge",
-	.release = cxl_nvdimm_bridge_release,
-	.groups = cxl_nvdimm_bridge_attribute_groups,
-};
-
-struct cxl_nvdimm_bridge *to_cxl_nvdimm_bridge(struct device *dev)
-{
-	if (dev_WARN_ONCE(dev, dev->type != &cxl_nvdimm_bridge_type,
-			  "not a cxl_nvdimm_bridge device\n"))
-		return NULL;
-	return container_of(dev, struct cxl_nvdimm_bridge, dev);
-}
-EXPORT_SYMBOL_GPL(to_cxl_nvdimm_bridge);
-
-static struct cxl_nvdimm_bridge *
-cxl_nvdimm_bridge_alloc(struct cxl_port *port)
-{
-	struct cxl_nvdimm_bridge *cxl_nvb;
-	struct device *dev;
-
-	cxl_nvb = kzalloc(sizeof(*cxl_nvb), GFP_KERNEL);
-	if (!cxl_nvb)
-		return ERR_PTR(-ENOMEM);
-
-	dev = &cxl_nvb->dev;
-	cxl_nvb->port = port;
-	cxl_nvb->state = CXL_NVB_NEW;
-	device_initialize(dev);
-	device_set_pm_not_required(dev);
-	dev->parent = &port->dev;
-	dev->bus = &cxl_bus_type;
-	dev->type = &cxl_nvdimm_bridge_type;
-
-	return cxl_nvb;
-}
-
-static void unregister_nvb(void *_cxl_nvb)
-{
-	struct cxl_nvdimm_bridge *cxl_nvb = _cxl_nvb;
-	bool flush;
-
-	/*
-	 * If the bridge was ever activated then there might be in-flight state
-	 * work to flush. Once the state has been changed to 'dead' then no new
-	 * work can be queued by user-triggered bind.
-	 */
-	device_lock(&cxl_nvb->dev);
-	flush = cxl_nvb->state != CXL_NVB_NEW;
-	cxl_nvb->state = CXL_NVB_DEAD;
-	device_unlock(&cxl_nvb->dev);
-
-	/*
-	 * Even though the device core will trigger device_release_driver()
-	 * before the unregister, it does not know about the fact that
-	 * cxl_nvdimm_bridge_driver defers ->remove() work. So, do the driver
-	 * release not and flush it before tearing down the nvdimm device
-	 * hierarchy.
-	 */
-	device_release_driver(&cxl_nvb->dev);
-	if (flush)
-		flush_work(&cxl_nvb->state_work);
-	device_unregister(&cxl_nvb->dev);
-}
-
-struct cxl_nvdimm_bridge *devm_cxl_add_nvdimm_bridge(struct device *host,
-						     struct cxl_port *port)
-{
-	struct cxl_nvdimm_bridge *cxl_nvb;
-	struct device *dev;
-	int rc;
-
-	if (!IS_ENABLED(CONFIG_CXL_PMEM))
-		return ERR_PTR(-ENXIO);
-
-	cxl_nvb = cxl_nvdimm_bridge_alloc(port);
-	if (IS_ERR(cxl_nvb))
-		return cxl_nvb;
-
-	dev = &cxl_nvb->dev;
-	rc = dev_set_name(dev, "nvdimm-bridge");
-	if (rc)
-		goto err;
-
-	rc = device_add(dev);
-	if (rc)
-		goto err;
-
-	rc = devm_add_action_or_reset(host, unregister_nvb, cxl_nvb);
-	if (rc)
-		return ERR_PTR(rc);
-
-	return cxl_nvb;
-
-err:
-	put_device(dev);
-	return ERR_PTR(rc);
-}
-EXPORT_SYMBOL_GPL(devm_cxl_add_nvdimm_bridge);
-
-static void cxl_nvdimm_release(struct device *dev)
-{
-	struct cxl_nvdimm *cxl_nvd = to_cxl_nvdimm(dev);
-
-	kfree(cxl_nvd);
-}
-
-static const struct attribute_group *cxl_nvdimm_attribute_groups[] = {
-	&cxl_base_attribute_group,
-	NULL,
-};
-
-static const struct device_type cxl_nvdimm_type = {
-	.name = "cxl_nvdimm",
-	.release = cxl_nvdimm_release,
-	.groups = cxl_nvdimm_attribute_groups,
-};
-
-bool is_cxl_nvdimm(struct device *dev)
-{
-	return dev->type == &cxl_nvdimm_type;
-}
-EXPORT_SYMBOL_GPL(is_cxl_nvdimm);
-
-struct cxl_nvdimm *to_cxl_nvdimm(struct device *dev)
-{
-	if (dev_WARN_ONCE(dev, !is_cxl_nvdimm(dev),
-			  "not a cxl_nvdimm device\n"))
-		return NULL;
-	return container_of(dev, struct cxl_nvdimm, dev);
-}
-EXPORT_SYMBOL_GPL(to_cxl_nvdimm);
-
-static struct cxl_nvdimm *cxl_nvdimm_alloc(struct cxl_memdev *cxlmd)
-{
-	struct cxl_nvdimm *cxl_nvd;
-	struct device *dev;
-
-	cxl_nvd = kzalloc(sizeof(*cxl_nvd), GFP_KERNEL);
-	if (!cxl_nvd)
-		return ERR_PTR(-ENOMEM);
-
-	dev = &cxl_nvd->dev;
-	cxl_nvd->cxlmd = cxlmd;
-	device_initialize(dev);
-	device_set_pm_not_required(dev);
-	dev->parent = &cxlmd->dev;
-	dev->bus = &cxl_bus_type;
-	dev->type = &cxl_nvdimm_type;
-
-	return cxl_nvd;
-}
-
-int devm_cxl_add_nvdimm(struct device *host, struct cxl_memdev *cxlmd)
-{
-	struct cxl_nvdimm *cxl_nvd;
-	struct device *dev;
-	int rc;
-
-	cxl_nvd = cxl_nvdimm_alloc(cxlmd);
-	if (IS_ERR(cxl_nvd))
-		return PTR_ERR(cxl_nvd);
-
-	dev = &cxl_nvd->dev;
-	rc = dev_set_name(dev, "pmem%d", cxlmd->id);
-	if (rc)
-		goto err;
-
-	rc = device_add(dev);
-	if (rc)
-		goto err;
-
-	dev_dbg(host, "%s: register %s\n", dev_name(dev->parent),
-		dev_name(dev));
-
-	return devm_add_action_or_reset(host, unregister_dev, dev);
-
-err:
-	put_device(dev);
-	return rc;
-}
-EXPORT_SYMBOL_GPL(devm_cxl_add_nvdimm);
-
-/**
- * cxl_probe_device_regs() - Detect CXL Device register blocks
- * @dev: Host device of the @base mapping
- * @base: Mapping of CXL 2.0 8.2.8 CXL Device Register Interface
- * @map: Map object describing the register block information found
- *
- * Probe for device register information and return it in map object.
- */
-void cxl_probe_device_regs(struct device *dev, void __iomem *base,
-			   struct cxl_device_reg_map *map)
-{
-	int cap, cap_count;
-	u64 cap_array;
-
-	*map = (struct cxl_device_reg_map){ 0 };
-
-	cap_array = readq(base + CXLDEV_CAP_ARRAY_OFFSET);
-	if (FIELD_GET(CXLDEV_CAP_ARRAY_ID_MASK, cap_array) !=
-	    CXLDEV_CAP_ARRAY_CAP_ID)
-		return;
-
-	cap_count = FIELD_GET(CXLDEV_CAP_ARRAY_COUNT_MASK, cap_array);
-
-	for (cap = 1; cap <= cap_count; cap++) {
-		u32 offset, length;
-		u16 cap_id;
-
-		cap_id = FIELD_GET(CXLDEV_CAP_HDR_CAP_ID_MASK,
-				   readl(base + cap * 0x10));
-		offset = readl(base + cap * 0x10 + 0x4);
-		length = readl(base + cap * 0x10 + 0x8);
-
-		switch (cap_id) {
-		case CXLDEV_CAP_CAP_ID_DEVICE_STATUS:
-			dev_dbg(dev, "found Status capability (0x%x)\n", offset);
-
-			map->status.valid = true;
-			map->status.offset = offset;
-			map->status.size = length;
-			break;
-		case CXLDEV_CAP_CAP_ID_PRIMARY_MAILBOX:
-			dev_dbg(dev, "found Mailbox capability (0x%x)\n", offset);
-			map->mbox.valid = true;
-			map->mbox.offset = offset;
-			map->mbox.size = length;
-			break;
-		case CXLDEV_CAP_CAP_ID_SECONDARY_MAILBOX:
-			dev_dbg(dev, "found Secondary Mailbox capability (0x%x)\n", offset);
-			break;
-		case CXLDEV_CAP_CAP_ID_MEMDEV:
-			dev_dbg(dev, "found Memory Device capability (0x%x)\n", offset);
-			map->memdev.valid = true;
-			map->memdev.offset = offset;
-			map->memdev.size = length;
-			break;
-		default:
-			if (cap_id >= 0x8000)
-				dev_dbg(dev, "Vendor cap ID: %#x offset: %#x\n", cap_id, offset);
-			else
-				dev_dbg(dev, "Unknown cap ID: %#x offset: %#x\n", cap_id, offset);
-			break;
-		}
-	}
-}
-EXPORT_SYMBOL_GPL(cxl_probe_device_regs);
-
-static void __iomem *devm_cxl_iomap_block(struct device *dev,
-					  resource_size_t addr,
-					  resource_size_t length)
-{
-	void __iomem *ret_val;
-	struct resource *res;
-
-	res = devm_request_mem_region(dev, addr, length, dev_name(dev));
-	if (!res) {
-		resource_size_t end = addr + length - 1;
-
-		dev_err(dev, "Failed to request region %pa-%pa\n", &addr, &end);
-		return NULL;
-	}
-
-	ret_val = devm_ioremap(dev, addr, length);
-	if (!ret_val)
-		dev_err(dev, "Failed to map region %pr\n", res);
-
-	return ret_val;
-}
-
-int cxl_map_component_regs(struct pci_dev *pdev,
-			   struct cxl_component_regs *regs,
-			   struct cxl_register_map *map)
-{
-	struct device *dev = &pdev->dev;
-	resource_size_t phys_addr;
-	resource_size_t length;
-
-	phys_addr = pci_resource_start(pdev, map->barno);
-	phys_addr += map->block_offset;
-
-	phys_addr += map->component_map.hdm_decoder.offset;
-	length = map->component_map.hdm_decoder.size;
-	regs->hdm_decoder = devm_cxl_iomap_block(dev, phys_addr, length);
-	if (!regs->hdm_decoder)
-		return -ENOMEM;
-
-	return 0;
-}
-EXPORT_SYMBOL_GPL(cxl_map_component_regs);
-
-int cxl_map_device_regs(struct pci_dev *pdev,
-			struct cxl_device_regs *regs,
-			struct cxl_register_map *map)
-{
-	struct device *dev = &pdev->dev;
-	resource_size_t phys_addr;
-
-	phys_addr = pci_resource_start(pdev, map->barno);
-	phys_addr += map->block_offset;
-
-	if (map->device_map.status.valid) {
-		resource_size_t addr;
-		resource_size_t length;
-
-		addr = phys_addr + map->device_map.status.offset;
-		length = map->device_map.status.size;
-		regs->status = devm_cxl_iomap_block(dev, addr, length);
-		if (!regs->status)
-			return -ENOMEM;
-	}
-
-	if (map->device_map.mbox.valid) {
-		resource_size_t addr;
-		resource_size_t length;
-
-		addr = phys_addr + map->device_map.mbox.offset;
-		length = map->device_map.mbox.size;
-		regs->mbox = devm_cxl_iomap_block(dev, addr, length);
-		if (!regs->mbox)
-			return -ENOMEM;
-	}
-
-	if (map->device_map.memdev.valid) {
-		resource_size_t addr;
-		resource_size_t length;
-
-		addr = phys_addr + map->device_map.memdev.offset;
-		length = map->device_map.memdev.size;
-		regs->memdev = devm_cxl_iomap_block(dev, addr, length);
-		if (!regs->memdev)
-			return -ENOMEM;
-	}
-
-	return 0;
-}
-EXPORT_SYMBOL_GPL(cxl_map_device_regs);
-
-/**
  * __cxl_driver_register - register a driver for the cxl bus
  * @cxl_drv: cxl driver structure to attach
  * @owner: owning module/driver
@@ -1034,13 +614,12 @@ static int cxl_bus_probe(struct device *dev)
 	return to_cxl_drv(dev->driver)->probe(dev);
 }
 
-static int cxl_bus_remove(struct device *dev)
+static void cxl_bus_remove(struct device *dev)
 {
 	struct cxl_driver *cxl_drv = to_cxl_drv(dev->driver);
 
 	if (cxl_drv->remove)
 		cxl_drv->remove(dev);
-	return 0;
 }
 
 struct bus_type cxl_bus_type = {
@@ -1054,12 +633,26 @@ EXPORT_SYMBOL_GPL(cxl_bus_type);
 
 static __init int cxl_core_init(void)
 {
-	return bus_register(&cxl_bus_type);
+	int rc;
+
+	rc = cxl_memdev_init();
+	if (rc)
+		return rc;
+
+	rc = bus_register(&cxl_bus_type);
+	if (rc)
+		goto err;
+	return 0;
+
+err:
+	cxl_memdev_exit();
+	return rc;
 }
 
 static void cxl_core_exit(void)
 {
 	bus_unregister(&cxl_bus_type);
+	cxl_memdev_exit();
 }
 
 module_init(cxl_core_init);
diff --git a/drivers/cxl/core/core.h b/drivers/cxl/core/core.h
new file mode 100644
index 000000000000..036a3c8106b4
--- /dev/null
+++ b/drivers/cxl/core/core.h
@@ -0,0 +1,20 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Copyright(c) 2020 Intel Corporation. */
+
+#ifndef __CXL_CORE_H__
+#define __CXL_CORE_H__
+
+extern const struct device_type cxl_nvdimm_bridge_type;
+extern const struct device_type cxl_nvdimm_type;
+
+extern struct attribute_group cxl_base_attribute_group;
+
+static inline void unregister_cxl_dev(void *dev)
+{
+	device_unregister(dev);
+}
+
+int cxl_memdev_init(void);
+void cxl_memdev_exit(void);
+
+#endif /* __CXL_CORE_H__ */
diff --git a/drivers/cxl/core/memdev.c b/drivers/cxl/core/memdev.c
new file mode 100644
index 000000000000..a9c317e32010
--- /dev/null
+++ b/drivers/cxl/core/memdev.c
@@ -0,0 +1,246 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright(c) 2020 Intel Corporation. */
+
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/idr.h>
+#include <linux/pci.h>
+#include <cxlmem.h>
+#include "core.h"
+
+/*
+ * An entire PCI topology full of devices should be enough for any
+ * config
+ */
+#define CXL_MEM_MAX_DEVS 65536
+
+static int cxl_mem_major;
+static DEFINE_IDA(cxl_memdev_ida);
+
+static void cxl_memdev_release(struct device *dev)
+{
+	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
+
+	ida_free(&cxl_memdev_ida, cxlmd->id);
+	kfree(cxlmd);
+}
+
+static char *cxl_memdev_devnode(struct device *dev, umode_t *mode, kuid_t *uid,
+				kgid_t *gid)
+{
+	return kasprintf(GFP_KERNEL, "cxl/%s", dev_name(dev));
+}
+
+static ssize_t firmware_version_show(struct device *dev,
+				     struct device_attribute *attr, char *buf)
+{
+	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
+	struct cxl_mem *cxlm = cxlmd->cxlm;
+
+	return sysfs_emit(buf, "%.16s\n", cxlm->firmware_version);
+}
+static DEVICE_ATTR_RO(firmware_version);
+
+static ssize_t payload_max_show(struct device *dev,
+				struct device_attribute *attr, char *buf)
+{
+	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
+	struct cxl_mem *cxlm = cxlmd->cxlm;
+
+	return sysfs_emit(buf, "%zu\n", cxlm->payload_size);
+}
+static DEVICE_ATTR_RO(payload_max);
+
+static ssize_t label_storage_size_show(struct device *dev,
+				       struct device_attribute *attr, char *buf)
+{
+	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
+	struct cxl_mem *cxlm = cxlmd->cxlm;
+
+	return sysfs_emit(buf, "%zu\n", cxlm->lsa_size);
+}
+static DEVICE_ATTR_RO(label_storage_size);
+
+static ssize_t ram_size_show(struct device *dev, struct device_attribute *attr,
+			     char *buf)
+{
+	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
+	struct cxl_mem *cxlm = cxlmd->cxlm;
+	unsigned long long len = range_len(&cxlm->ram_range);
+
+	return sysfs_emit(buf, "%#llx\n", len);
+}
+
+static struct device_attribute dev_attr_ram_size =
+	__ATTR(size, 0444, ram_size_show, NULL);
+
+static ssize_t pmem_size_show(struct device *dev, struct device_attribute *attr,
+			      char *buf)
+{
+	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
+	struct cxl_mem *cxlm = cxlmd->cxlm;
+	unsigned long long len = range_len(&cxlm->pmem_range);
+
+	return sysfs_emit(buf, "%#llx\n", len);
+}
+
+static struct device_attribute dev_attr_pmem_size =
+	__ATTR(size, 0444, pmem_size_show, NULL);
+
+static struct attribute *cxl_memdev_attributes[] = {
+	&dev_attr_firmware_version.attr,
+	&dev_attr_payload_max.attr,
+	&dev_attr_label_storage_size.attr,
+	NULL,
+};
+
+static struct attribute *cxl_memdev_pmem_attributes[] = {
+	&dev_attr_pmem_size.attr,
+	NULL,
+};
+
+static struct attribute *cxl_memdev_ram_attributes[] = {
+	&dev_attr_ram_size.attr,
+	NULL,
+};
+
+static struct attribute_group cxl_memdev_attribute_group = {
+	.attrs = cxl_memdev_attributes,
+};
+
+static struct attribute_group cxl_memdev_ram_attribute_group = {
+	.name = "ram",
+	.attrs = cxl_memdev_ram_attributes,
+};
+
+static struct attribute_group cxl_memdev_pmem_attribute_group = {
+	.name = "pmem",
+	.attrs = cxl_memdev_pmem_attributes,
+};
+
+static const struct attribute_group *cxl_memdev_attribute_groups[] = {
+	&cxl_memdev_attribute_group,
+	&cxl_memdev_ram_attribute_group,
+	&cxl_memdev_pmem_attribute_group,
+	NULL,
+};
+
+static const struct device_type cxl_memdev_type = {
+	.name = "cxl_memdev",
+	.release = cxl_memdev_release,
+	.devnode = cxl_memdev_devnode,
+	.groups = cxl_memdev_attribute_groups,
+};
+
+static void cxl_memdev_unregister(void *_cxlmd)
+{
+	struct cxl_memdev *cxlmd = _cxlmd;
+	struct device *dev = &cxlmd->dev;
+	struct cdev *cdev = &cxlmd->cdev;
+	const struct cdevm_file_operations *cdevm_fops;
+
+	cdevm_fops = container_of(cdev->ops, typeof(*cdevm_fops), fops);
+	cdevm_fops->shutdown(dev);
+
+	cdev_device_del(&cxlmd->cdev, dev);
+	put_device(dev);
+}
+
+static struct cxl_memdev *cxl_memdev_alloc(struct cxl_mem *cxlm,
+					   const struct file_operations *fops)
+{
+	struct pci_dev *pdev = cxlm->pdev;
+	struct cxl_memdev *cxlmd;
+	struct device *dev;
+	struct cdev *cdev;
+	int rc;
+
+	cxlmd = kzalloc(sizeof(*cxlmd), GFP_KERNEL);
+	if (!cxlmd)
+		return ERR_PTR(-ENOMEM);
+
+	rc = ida_alloc_range(&cxl_memdev_ida, 0, CXL_MEM_MAX_DEVS, GFP_KERNEL);
+	if (rc < 0)
+		goto err;
+	cxlmd->id = rc;
+
+	dev = &cxlmd->dev;
+	device_initialize(dev);
+	dev->parent = &pdev->dev;
+	dev->bus = &cxl_bus_type;
+	dev->devt = MKDEV(cxl_mem_major, cxlmd->id);
+	dev->type = &cxl_memdev_type;
+	device_set_pm_not_required(dev);
+
+	cdev = &cxlmd->cdev;
+	cdev_init(cdev, fops);
+	return cxlmd;
+
+err:
+	kfree(cxlmd);
+	return ERR_PTR(rc);
+}
+
+struct cxl_memdev *
+devm_cxl_add_memdev(struct device *host, struct cxl_mem *cxlm,
+		    const struct cdevm_file_operations *cdevm_fops)
+{
+	struct cxl_memdev *cxlmd;
+	struct device *dev;
+	struct cdev *cdev;
+	int rc;
+
+	cxlmd = cxl_memdev_alloc(cxlm, &cdevm_fops->fops);
+	if (IS_ERR(cxlmd))
+		return cxlmd;
+
+	dev = &cxlmd->dev;
+	rc = dev_set_name(dev, "mem%d", cxlmd->id);
+	if (rc)
+		goto err;
+
+	/*
+	 * Activate ioctl operations, no cxl_memdev_rwsem manipulation
+	 * needed as this is ordered with cdev_add() publishing the device.
+	 */
+	cxlmd->cxlm = cxlm;
+
+	cdev = &cxlmd->cdev;
+	rc = cdev_device_add(cdev, dev);
+	if (rc)
+		goto err;
+
+	rc = devm_add_action_or_reset(host, cxl_memdev_unregister, cxlmd);
+	if (rc)
+		return ERR_PTR(rc);
+	return cxlmd;
+
+err:
+	/*
+	 * The cdev was briefly live, shutdown any ioctl operations that
+	 * saw that state.
+	 */
+	cdevm_fops->shutdown(dev);
+	put_device(dev);
+	return ERR_PTR(rc);
+}
+EXPORT_SYMBOL_GPL(devm_cxl_add_memdev);
+
+__init int cxl_memdev_init(void)
+{
+	dev_t devt;
+	int rc;
+
+	rc = alloc_chrdev_region(&devt, 0, CXL_MEM_MAX_DEVS, "cxl");
+	if (rc)
+		return rc;
+
+	cxl_mem_major = MAJOR(devt);
+
+	return 0;
+}
+
+void cxl_memdev_exit(void)
+{
+	unregister_chrdev_region(MKDEV(cxl_mem_major, 0), CXL_MEM_MAX_DEVS);
+}
diff --git a/drivers/cxl/core/pmem.c b/drivers/cxl/core/pmem.c
new file mode 100644
index 000000000000..d24570f5b8ba
--- /dev/null
+++ b/drivers/cxl/core/pmem.c
@@ -0,0 +1,230 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright(c) 2020 Intel Corporation. */
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <cxlmem.h>
+#include <cxl.h>
+#include "core.h"
+
+/**
+ * DOC: cxl pmem
+ *
+ * The core CXL PMEM infrastructure supports persistent memory
+ * provisioning and serves as a bridge to the LIBNVDIMM subsystem. A CXL
+ * 'bridge' device is added at the root of a CXL device topology if
+ * platform firmware advertises at least one persistent memory capable
+ * CXL window. That root-level bridge corresponds to a LIBNVDIMM 'bus'
+ * device. Then for each cxl_memdev in the CXL device topology a bridge
+ * device is added to host a LIBNVDIMM dimm object. When these bridges
+ * are registered native LIBNVDIMM uapis are translated to CXL
+ * operations, for example, namespace label access commands.
+ */
+
+static void cxl_nvdimm_bridge_release(struct device *dev)
+{
+	struct cxl_nvdimm_bridge *cxl_nvb = to_cxl_nvdimm_bridge(dev);
+
+	kfree(cxl_nvb);
+}
+
+static const struct attribute_group *cxl_nvdimm_bridge_attribute_groups[] = {
+	&cxl_base_attribute_group,
+	NULL,
+};
+
+const struct device_type cxl_nvdimm_bridge_type = {
+	.name = "cxl_nvdimm_bridge",
+	.release = cxl_nvdimm_bridge_release,
+	.groups = cxl_nvdimm_bridge_attribute_groups,
+};
+
+struct cxl_nvdimm_bridge *to_cxl_nvdimm_bridge(struct device *dev)
+{
+	if (dev_WARN_ONCE(dev, dev->type != &cxl_nvdimm_bridge_type,
+			  "not a cxl_nvdimm_bridge device\n"))
+		return NULL;
+	return container_of(dev, struct cxl_nvdimm_bridge, dev);
+}
+EXPORT_SYMBOL_GPL(to_cxl_nvdimm_bridge);
+
+static struct cxl_nvdimm_bridge *
+cxl_nvdimm_bridge_alloc(struct cxl_port *port)
+{
+	struct cxl_nvdimm_bridge *cxl_nvb;
+	struct device *dev;
+
+	cxl_nvb = kzalloc(sizeof(*cxl_nvb), GFP_KERNEL);
+	if (!cxl_nvb)
+		return ERR_PTR(-ENOMEM);
+
+	dev = &cxl_nvb->dev;
+	cxl_nvb->port = port;
+	cxl_nvb->state = CXL_NVB_NEW;
+	device_initialize(dev);
+	device_set_pm_not_required(dev);
+	dev->parent = &port->dev;
+	dev->bus = &cxl_bus_type;
+	dev->type = &cxl_nvdimm_bridge_type;
+
+	return cxl_nvb;
+}
+
+static void unregister_nvb(void *_cxl_nvb)
+{
+	struct cxl_nvdimm_bridge *cxl_nvb = _cxl_nvb;
+	bool flush;
+
+	/*
+	 * If the bridge was ever activated then there might be in-flight state
+	 * work to flush. Once the state has been changed to 'dead' then no new
+	 * work can be queued by user-triggered bind.
+	 */
+	device_lock(&cxl_nvb->dev);
+	flush = cxl_nvb->state != CXL_NVB_NEW;
+	cxl_nvb->state = CXL_NVB_DEAD;
+	device_unlock(&cxl_nvb->dev);
+
+	/*
+	 * Even though the device core will trigger device_release_driver()
+	 * before the unregister, it does not know about the fact that
+	 * cxl_nvdimm_bridge_driver defers ->remove() work. So, do the driver
+	 * release not and flush it before tearing down the nvdimm device
+	 * hierarchy.
+	 */
+	device_release_driver(&cxl_nvb->dev);
+	if (flush)
+		flush_work(&cxl_nvb->state_work);
+	device_unregister(&cxl_nvb->dev);
+}
+
+/**
+ * devm_cxl_add_nvdimm_bridge() - add the root of a LIBNVDIMM topology
+ * @host: platform firmware root device
+ * @port: CXL port at the root of a CXL topology
+ *
+ * Return: bridge device that can host cxl_nvdimm objects
+ */
+struct cxl_nvdimm_bridge *devm_cxl_add_nvdimm_bridge(struct device *host,
+						     struct cxl_port *port)
+{
+	struct cxl_nvdimm_bridge *cxl_nvb;
+	struct device *dev;
+	int rc;
+
+	if (!IS_ENABLED(CONFIG_CXL_PMEM))
+		return ERR_PTR(-ENXIO);
+
+	cxl_nvb = cxl_nvdimm_bridge_alloc(port);
+	if (IS_ERR(cxl_nvb))
+		return cxl_nvb;
+
+	dev = &cxl_nvb->dev;
+	rc = dev_set_name(dev, "nvdimm-bridge");
+	if (rc)
+		goto err;
+
+	rc = device_add(dev);
+	if (rc)
+		goto err;
+
+	rc = devm_add_action_or_reset(host, unregister_nvb, cxl_nvb);
+	if (rc)
+		return ERR_PTR(rc);
+
+	return cxl_nvb;
+
+err:
+	put_device(dev);
+	return ERR_PTR(rc);
+}
+EXPORT_SYMBOL_GPL(devm_cxl_add_nvdimm_bridge);
+
+static void cxl_nvdimm_release(struct device *dev)
+{
+	struct cxl_nvdimm *cxl_nvd = to_cxl_nvdimm(dev);
+
+	kfree(cxl_nvd);
+}
+
+static const struct attribute_group *cxl_nvdimm_attribute_groups[] = {
+	&cxl_base_attribute_group,
+	NULL,
+};
+
+const struct device_type cxl_nvdimm_type = {
+	.name = "cxl_nvdimm",
+	.release = cxl_nvdimm_release,
+	.groups = cxl_nvdimm_attribute_groups,
+};
+
+bool is_cxl_nvdimm(struct device *dev)
+{
+	return dev->type == &cxl_nvdimm_type;
+}
+EXPORT_SYMBOL_GPL(is_cxl_nvdimm);
+
+struct cxl_nvdimm *to_cxl_nvdimm(struct device *dev)
+{
+	if (dev_WARN_ONCE(dev, !is_cxl_nvdimm(dev),
+			  "not a cxl_nvdimm device\n"))
+		return NULL;
+	return container_of(dev, struct cxl_nvdimm, dev);
+}
+EXPORT_SYMBOL_GPL(to_cxl_nvdimm);
+
+static struct cxl_nvdimm *cxl_nvdimm_alloc(struct cxl_memdev *cxlmd)
+{
+	struct cxl_nvdimm *cxl_nvd;
+	struct device *dev;
+
+	cxl_nvd = kzalloc(sizeof(*cxl_nvd), GFP_KERNEL);
+	if (!cxl_nvd)
+		return ERR_PTR(-ENOMEM);
+
+	dev = &cxl_nvd->dev;
+	cxl_nvd->cxlmd = cxlmd;
+	device_initialize(dev);
+	device_set_pm_not_required(dev);
+	dev->parent = &cxlmd->dev;
+	dev->bus = &cxl_bus_type;
+	dev->type = &cxl_nvdimm_type;
+
+	return cxl_nvd;
+}
+
+/**
+ * devm_cxl_add_nvdimm() - add a bridge between a cxl_memdev and an nvdimm
+ * @host: same host as @cxlmd
+ * @cxlmd: cxl_memdev instance that will perform LIBNVDIMM operations
+ *
+ * Return: 0 on success negative error code on failure.
+ */
+int devm_cxl_add_nvdimm(struct device *host, struct cxl_memdev *cxlmd)
+{
+	struct cxl_nvdimm *cxl_nvd;
+	struct device *dev;
+	int rc;
+
+	cxl_nvd = cxl_nvdimm_alloc(cxlmd);
+	if (IS_ERR(cxl_nvd))
+		return PTR_ERR(cxl_nvd);
+
+	dev = &cxl_nvd->dev;
+	rc = dev_set_name(dev, "pmem%d", cxlmd->id);
+	if (rc)
+		goto err;
+
+	rc = device_add(dev);
+	if (rc)
+		goto err;
+
+	dev_dbg(host, "%s: register %s\n", dev_name(dev->parent),
+		dev_name(dev));
+
+	return devm_add_action_or_reset(host, unregister_cxl_dev, dev);
+
+err:
+	put_device(dev);
+	return rc;
+}
+EXPORT_SYMBOL_GPL(devm_cxl_add_nvdimm);
diff --git a/drivers/cxl/core/regs.c b/drivers/cxl/core/regs.c
new file mode 100644
index 000000000000..41de4a136ecd
--- /dev/null
+++ b/drivers/cxl/core/regs.c
@@ -0,0 +1,249 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* Copyright(c) 2020 Intel Corporation. */
+#include <linux/io-64-nonatomic-lo-hi.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/pci.h>
+#include <cxlmem.h>
+
+/**
+ * DOC: cxl registers
+ *
+ * CXL device capabilities are enumerated by PCI DVSEC (Designated
+ * Vendor-specific) and / or descriptors provided by platform firmware.
+ * They can be defined as a set like the device and component registers
+ * mandated by CXL Section 8.1.12.2 Memory Device PCIe Capabilities and
+ * Extended Capabilities, or they can be individual capabilities
+ * appended to bridged and endpoint devices.
+ *
+ * Provide common infrastructure for enumerating and mapping these
+ * discrete capabilities.
+ */
+
+/**
+ * cxl_probe_component_regs() - Detect CXL Component register blocks
+ * @dev: Host device of the @base mapping
+ * @base: Mapping containing the HDM Decoder Capability Header
+ * @map: Map object describing the register block information found
+ *
+ * See CXL 2.0 8.2.4 Component Register Layout and Definition
+ * See CXL 2.0 8.2.5.5 CXL Device Register Interface
+ *
+ * Probe for component register information and return it in map object.
+ */
+void cxl_probe_component_regs(struct device *dev, void __iomem *base,
+			      struct cxl_component_reg_map *map)
+{
+	int cap, cap_count;
+	u64 cap_array;
+
+	*map = (struct cxl_component_reg_map) { 0 };
+
+	/*
+	 * CXL.cache and CXL.mem registers are at offset 0x1000 as defined in
+	 * CXL 2.0 8.2.4 Table 141.
+	 */
+	base += CXL_CM_OFFSET;
+
+	cap_array = readq(base + CXL_CM_CAP_HDR_OFFSET);
+
+	if (FIELD_GET(CXL_CM_CAP_HDR_ID_MASK, cap_array) != CM_CAP_HDR_CAP_ID) {
+		dev_err(dev,
+			"Couldn't locate the CXL.cache and CXL.mem capability array header./n");
+		return;
+	}
+
+	/* It's assumed that future versions will be backward compatible */
+	cap_count = FIELD_GET(CXL_CM_CAP_HDR_ARRAY_SIZE_MASK, cap_array);
+
+	for (cap = 1; cap <= cap_count; cap++) {
+		void __iomem *register_block;
+		u32 hdr;
+		int decoder_cnt;
+		u16 cap_id, offset;
+		u32 length;
+
+		hdr = readl(base + cap * 0x4);
+
+		cap_id = FIELD_GET(CXL_CM_CAP_HDR_ID_MASK, hdr);
+		offset = FIELD_GET(CXL_CM_CAP_PTR_MASK, hdr);
+		register_block = base + offset;
+
+		switch (cap_id) {
+		case CXL_CM_CAP_CAP_ID_HDM:
+			dev_dbg(dev, "found HDM decoder capability (0x%x)\n",
+				offset);
+
+			hdr = readl(register_block);
+
+			decoder_cnt = cxl_hdm_decoder_count(hdr);
+			length = 0x20 * decoder_cnt + 0x10;
+
+			map->hdm_decoder.valid = true;
+			map->hdm_decoder.offset = CXL_CM_OFFSET + offset;
+			map->hdm_decoder.size = length;
+			break;
+		default:
+			dev_dbg(dev, "Unknown CM cap ID: %d (0x%x)\n", cap_id,
+				offset);
+			break;
+		}
+	}
+}
+EXPORT_SYMBOL_GPL(cxl_probe_component_regs);
+
+/**
+ * cxl_probe_device_regs() - Detect CXL Device register blocks
+ * @dev: Host device of the @base mapping
+ * @base: Mapping of CXL 2.0 8.2.8 CXL Device Register Interface
+ * @map: Map object describing the register block information found
+ *
+ * Probe for device register information and return it in map object.
+ */
+void cxl_probe_device_regs(struct device *dev, void __iomem *base,
+			   struct cxl_device_reg_map *map)
+{
+	int cap, cap_count;
+	u64 cap_array;
+
+	*map = (struct cxl_device_reg_map){ 0 };
+
+	cap_array = readq(base + CXLDEV_CAP_ARRAY_OFFSET);
+	if (FIELD_GET(CXLDEV_CAP_ARRAY_ID_MASK, cap_array) !=
+	    CXLDEV_CAP_ARRAY_CAP_ID)
+		return;
+
+	cap_count = FIELD_GET(CXLDEV_CAP_ARRAY_COUNT_MASK, cap_array);
+
+	for (cap = 1; cap <= cap_count; cap++) {
+		u32 offset, length;
+		u16 cap_id;
+
+		cap_id = FIELD_GET(CXLDEV_CAP_HDR_CAP_ID_MASK,
+				   readl(base + cap * 0x10));
+		offset = readl(base + cap * 0x10 + 0x4);
+		length = readl(base + cap * 0x10 + 0x8);
+
+		switch (cap_id) {
+		case CXLDEV_CAP_CAP_ID_DEVICE_STATUS:
+			dev_dbg(dev, "found Status capability (0x%x)\n", offset);
+
+			map->status.valid = true;
+			map->status.offset = offset;
+			map->status.size = length;
+			break;
+		case CXLDEV_CAP_CAP_ID_PRIMARY_MAILBOX:
+			dev_dbg(dev, "found Mailbox capability (0x%x)\n", offset);
+			map->mbox.valid = true;
+			map->mbox.offset = offset;
+			map->mbox.size = length;
+			break;
+		case CXLDEV_CAP_CAP_ID_SECONDARY_MAILBOX:
+			dev_dbg(dev, "found Secondary Mailbox capability (0x%x)\n", offset);
+			break;
+		case CXLDEV_CAP_CAP_ID_MEMDEV:
+			dev_dbg(dev, "found Memory Device capability (0x%x)\n", offset);
+			map->memdev.valid = true;
+			map->memdev.offset = offset;
+			map->memdev.size = length;
+			break;
+		default:
+			if (cap_id >= 0x8000)
+				dev_dbg(dev, "Vendor cap ID: %#x offset: %#x\n", cap_id, offset);
+			else
+				dev_dbg(dev, "Unknown cap ID: %#x offset: %#x\n", cap_id, offset);
+			break;
+		}
+	}
+}
+EXPORT_SYMBOL_GPL(cxl_probe_device_regs);
+
+static void __iomem *devm_cxl_iomap_block(struct device *dev,
+					  resource_size_t addr,
+					  resource_size_t length)
+{
+	void __iomem *ret_val;
+	struct resource *res;
+
+	res = devm_request_mem_region(dev, addr, length, dev_name(dev));
+	if (!res) {
+		resource_size_t end = addr + length - 1;
+
+		dev_err(dev, "Failed to request region %pa-%pa\n", &addr, &end);
+		return NULL;
+	}
+
+	ret_val = devm_ioremap(dev, addr, length);
+	if (!ret_val)
+		dev_err(dev, "Failed to map region %pr\n", res);
+
+	return ret_val;
+}
+
+int cxl_map_component_regs(struct pci_dev *pdev,
+			   struct cxl_component_regs *regs,
+			   struct cxl_register_map *map)
+{
+	struct device *dev = &pdev->dev;
+	resource_size_t phys_addr;
+	resource_size_t length;
+
+	phys_addr = pci_resource_start(pdev, map->barno);
+	phys_addr += map->block_offset;
+
+	phys_addr += map->component_map.hdm_decoder.offset;
+	length = map->component_map.hdm_decoder.size;
+	regs->hdm_decoder = devm_cxl_iomap_block(dev, phys_addr, length);
+	if (!regs->hdm_decoder)
+		return -ENOMEM;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cxl_map_component_regs);
+
+int cxl_map_device_regs(struct pci_dev *pdev,
+			struct cxl_device_regs *regs,
+			struct cxl_register_map *map)
+{
+	struct device *dev = &pdev->dev;
+	resource_size_t phys_addr;
+
+	phys_addr = pci_resource_start(pdev, map->barno);
+	phys_addr += map->block_offset;
+
+	if (map->device_map.status.valid) {
+		resource_size_t addr;
+		resource_size_t length;
+
+		addr = phys_addr + map->device_map.status.offset;
+		length = map->device_map.status.size;
+		regs->status = devm_cxl_iomap_block(dev, addr, length);
+		if (!regs->status)
+			return -ENOMEM;
+	}
+
+	if (map->device_map.mbox.valid) {
+		resource_size_t addr;
+		resource_size_t length;
+
+		addr = phys_addr + map->device_map.mbox.offset;
+		length = map->device_map.mbox.size;
+		regs->mbox = devm_cxl_iomap_block(dev, addr, length);
+		if (!regs->mbox)
+			return -ENOMEM;
+	}
+
+	if (map->device_map.memdev.valid) {
+		resource_size_t addr;
+		resource_size_t length;
+
+		addr = phys_addr + map->device_map.memdev.offset;
+		length = map->device_map.memdev.size;
+		regs->memdev = devm_cxl_iomap_block(dev, addr, length);
+		if (!regs->memdev)
+			return -ENOMEM;
+	}
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(cxl_map_device_regs);
diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
index b6bda39a59e3..53927f9fa77e 100644
--- a/drivers/cxl/cxl.h
+++ b/drivers/cxl/cxl.h
@@ -140,7 +140,6 @@ struct cxl_device_reg_map {
 };
 
 struct cxl_register_map {
-	struct list_head list;
 	u64 block_offset;
 	u8 reg_type;
 	u8 barno;
diff --git a/drivers/cxl/mem.h b/drivers/cxl/cxlmem.h
index 8f02d02b26b4..6c0b1e2ea97c 100644
--- a/drivers/cxl/mem.h
+++ b/drivers/cxl/cxlmem.h
@@ -28,11 +28,20 @@
 	(FIELD_GET(CXLMDEV_RESET_NEEDED_MASK, status) !=                       \
 	 CXLMDEV_RESET_NEEDED_NOT)
 
-/*
- * An entire PCI topology full of devices should be enough for any
- * config
+/**
+ * struct cdevm_file_operations - devm coordinated cdev file operations
+ * @fops: file operations that are synchronized against @shutdown
+ * @shutdown: disconnect driver data
+ *
+ * @shutdown is invoked in the devres release path to disconnect any
+ * driver instance data from @dev. It assumes synchronization with any
+ * fops operation that requires driver data. After @shutdown an
+ * operation may only reference @device data.
  */
-#define CXL_MEM_MAX_DEVS 65536
+struct cdevm_file_operations {
+	struct file_operations fops;
+	void (*shutdown)(struct device *dev);
+};
 
 /**
  * struct cxl_memdev - CXL bus object representing a Type-3 Memory Device
@@ -48,6 +57,15 @@ struct cxl_memdev {
 	int id;
 };
 
+static inline struct cxl_memdev *to_cxl_memdev(struct device *dev)
+{
+	return container_of(dev, struct cxl_memdev, dev);
+}
+
+struct cxl_memdev *
+devm_cxl_add_memdev(struct device *host, struct cxl_mem *cxlm,
+		    const struct cdevm_file_operations *cdevm_fops);
+
 /**
  * struct cxl_mem - A CXL memory device
  * @pdev: The PCI device associated with this CXL device.
@@ -77,5 +95,14 @@ struct cxl_mem {
 
 	struct range pmem_range;
 	struct range ram_range;
+	u64 total_bytes;
+	u64 volatile_only_bytes;
+	u64 persistent_only_bytes;
+	u64 partition_align_bytes;
+
+	u64 active_volatile_bytes;
+	u64 active_persistent_bytes;
+	u64 next_volatile_bytes;
+	u64 next_persistent_bytes;
 };
 #endif /* __CXL_MEM_H__ */
diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c
index 4cf351a3cf99..8e45aa07d662 100644
--- a/drivers/cxl/pci.c
+++ b/drivers/cxl/pci.c
@@ -12,9 +12,9 @@
 #include <linux/pci.h>
 #include <linux/io.h>
 #include <linux/io-64-nonatomic-lo-hi.h>
+#include "cxlmem.h"
 #include "pci.h"
 #include "cxl.h"
-#include "mem.h"
 
 /**
  * DOC: cxl pci
@@ -64,6 +64,15 @@ enum opcode {
 	CXL_MBOX_OP_MAX			= 0x10000
 };
 
+/*
+ * CXL 2.0 - Memory capacity multiplier
+ * See Section 8.2.9.5
+ *
+ * Volatile, Persistent, and Partition capacities are specified to be in
+ * multiples of 256MB - define a multiplier to convert to/from bytes.
+ */
+#define CXL_CAPACITY_MULTIPLIER SZ_256M
+
 /**
  * struct mbox_cmd - A command to be submitted to hardware.
  * @opcode: (input) The command set and command submitted to hardware.
@@ -94,8 +103,6 @@ struct mbox_cmd {
 #define CXL_MBOX_SUCCESS 0
 };
 
-static int cxl_mem_major;
-static DEFINE_IDA(cxl_memdev_ida);
 static DECLARE_RWSEM(cxl_memdev_rwsem);
 static struct dentry *cxl_debugfs;
 static bool cxl_raw_allow_all;
@@ -568,7 +575,7 @@ static bool cxl_mem_raw_command_allowed(u16 opcode)
 	if (!IS_ENABLED(CONFIG_CXL_MEM_RAW_COMMANDS))
 		return false;
 
-	if (security_locked_down(LOCKDOWN_NONE))
+	if (security_locked_down(LOCKDOWN_PCI_ACCESS))
 		return false;
 
 	if (cxl_raw_allow_all)
@@ -806,13 +813,25 @@ static int cxl_memdev_release_file(struct inode *inode, struct file *file)
 	return 0;
 }
 
-static const struct file_operations cxl_memdev_fops = {
-	.owner = THIS_MODULE,
-	.unlocked_ioctl = cxl_memdev_ioctl,
-	.open = cxl_memdev_open,
-	.release = cxl_memdev_release_file,
-	.compat_ioctl = compat_ptr_ioctl,
-	.llseek = noop_llseek,
+static void cxl_memdev_shutdown(struct device *dev)
+{
+	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
+
+	down_write(&cxl_memdev_rwsem);
+	cxlmd->cxlm = NULL;
+	up_write(&cxl_memdev_rwsem);
+}
+
+static const struct cdevm_file_operations cxl_memdev_fops = {
+	.fops = {
+		.owner = THIS_MODULE,
+		.unlocked_ioctl = cxl_memdev_ioctl,
+		.open = cxl_memdev_open,
+		.release = cxl_memdev_release_file,
+		.compat_ioctl = compat_ptr_ioctl,
+		.llseek = noop_llseek,
+	},
+	.shutdown = cxl_memdev_shutdown,
 };
 
 static inline struct cxl_mem_command *cxl_mem_find_command(u16 opcode)
@@ -1022,8 +1041,8 @@ static int cxl_probe_regs(struct cxl_mem *cxlm, void __iomem *base,
 		    !dev_map->memdev.valid) {
 			dev_err(dev, "registers not found: %s%s%s\n",
 				!dev_map->status.valid ? "status " : "",
-				!dev_map->mbox.valid ? "status " : "",
-				!dev_map->memdev.valid ? "status " : "");
+				!dev_map->mbox.valid ? "mbox " : "",
+				!dev_map->memdev.valid ? "memdev " : "");
 			return -ENXIO;
 		}
 
@@ -1081,9 +1100,8 @@ static int cxl_mem_setup_regs(struct cxl_mem *cxlm)
 	struct device *dev = &pdev->dev;
 	u32 regloc_size, regblocks;
 	void __iomem *base;
-	int regloc, i;
-	struct cxl_register_map *map, *n;
-	LIST_HEAD(register_maps);
+	int regloc, i, n_maps;
+	struct cxl_register_map *map, maps[CXL_REGLOC_RBI_TYPES];
 	int ret = 0;
 
 	regloc = cxl_mem_dvsec(pdev, PCI_DVSEC_ID_CXL_REGLOC_DVSEC_ID);
@@ -1102,20 +1120,12 @@ static int cxl_mem_setup_regs(struct cxl_mem *cxlm)
 	regloc += PCI_DVSEC_ID_CXL_REGLOC_BLOCK1_OFFSET;
 	regblocks = (regloc_size - PCI_DVSEC_ID_CXL_REGLOC_BLOCK1_OFFSET) / 8;
 
-	for (i = 0; i < regblocks; i++, regloc += 8) {
+	for (i = 0, n_maps = 0; i < regblocks; i++, regloc += 8) {
 		u32 reg_lo, reg_hi;
 		u8 reg_type;
 		u64 offset;
 		u8 bar;
 
-		map = kzalloc(sizeof(*map), GFP_KERNEL);
-		if (!map) {
-			ret = -ENOMEM;
-			goto free_maps;
-		}
-
-		list_add(&map->list, &register_maps);
-
 		pci_read_config_dword(pdev, regloc, &reg_lo);
 		pci_read_config_dword(pdev, regloc + 4, &reg_hi);
 
@@ -1125,12 +1135,15 @@ static int cxl_mem_setup_regs(struct cxl_mem *cxlm)
 		dev_dbg(dev, "Found register block in bar %u @ 0x%llx of type %u\n",
 			bar, offset, reg_type);
 
+		/* Ignore unknown register block types */
+		if (reg_type > CXL_REGLOC_RBI_MEMDEV)
+			continue;
+
 		base = cxl_mem_map_regblock(cxlm, bar, offset);
-		if (!base) {
-			ret = -ENOMEM;
-			goto free_maps;
-		}
+		if (!base)
+			return -ENOMEM;
 
+		map = &maps[n_maps];
 		map->barno = bar;
 		map->block_offset = offset;
 		map->reg_type = reg_type;
@@ -1141,240 +1154,22 @@ static int cxl_mem_setup_regs(struct cxl_mem *cxlm)
 		cxl_mem_unmap_regblock(cxlm, base);
 
 		if (ret)
-			goto free_maps;
+			return ret;
+
+		n_maps++;
 	}
 
 	pci_release_mem_regions(pdev);
 
-	list_for_each_entry(map, &register_maps, list) {
-		ret = cxl_map_regs(cxlm, map);
+	for (i = 0; i < n_maps; i++) {
+		ret = cxl_map_regs(cxlm, &maps[i]);
 		if (ret)
-			goto free_maps;
-	}
-
-free_maps:
-	list_for_each_entry_safe(map, n, &register_maps, list) {
-		list_del(&map->list);
-		kfree(map);
+			break;
 	}
 
 	return ret;
 }
 
-static struct cxl_memdev *to_cxl_memdev(struct device *dev)
-{
-	return container_of(dev, struct cxl_memdev, dev);
-}
-
-static void cxl_memdev_release(struct device *dev)
-{
-	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
-
-	ida_free(&cxl_memdev_ida, cxlmd->id);
-	kfree(cxlmd);
-}
-
-static char *cxl_memdev_devnode(struct device *dev, umode_t *mode, kuid_t *uid,
-				kgid_t *gid)
-{
-	return kasprintf(GFP_KERNEL, "cxl/%s", dev_name(dev));
-}
-
-static ssize_t firmware_version_show(struct device *dev,
-				     struct device_attribute *attr, char *buf)
-{
-	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
-	struct cxl_mem *cxlm = cxlmd->cxlm;
-
-	return sysfs_emit(buf, "%.16s\n", cxlm->firmware_version);
-}
-static DEVICE_ATTR_RO(firmware_version);
-
-static ssize_t payload_max_show(struct device *dev,
-				struct device_attribute *attr, char *buf)
-{
-	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
-	struct cxl_mem *cxlm = cxlmd->cxlm;
-
-	return sysfs_emit(buf, "%zu\n", cxlm->payload_size);
-}
-static DEVICE_ATTR_RO(payload_max);
-
-static ssize_t label_storage_size_show(struct device *dev,
-				struct device_attribute *attr, char *buf)
-{
-	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
-	struct cxl_mem *cxlm = cxlmd->cxlm;
-
-	return sysfs_emit(buf, "%zu\n", cxlm->lsa_size);
-}
-static DEVICE_ATTR_RO(label_storage_size);
-
-static ssize_t ram_size_show(struct device *dev, struct device_attribute *attr,
-			     char *buf)
-{
-	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
-	struct cxl_mem *cxlm = cxlmd->cxlm;
-	unsigned long long len = range_len(&cxlm->ram_range);
-
-	return sysfs_emit(buf, "%#llx\n", len);
-}
-
-static struct device_attribute dev_attr_ram_size =
-	__ATTR(size, 0444, ram_size_show, NULL);
-
-static ssize_t pmem_size_show(struct device *dev, struct device_attribute *attr,
-			      char *buf)
-{
-	struct cxl_memdev *cxlmd = to_cxl_memdev(dev);
-	struct cxl_mem *cxlm = cxlmd->cxlm;
-	unsigned long long len = range_len(&cxlm->pmem_range);
-
-	return sysfs_emit(buf, "%#llx\n", len);
-}
-
-static struct device_attribute dev_attr_pmem_size =
-	__ATTR(size, 0444, pmem_size_show, NULL);
-
-static struct attribute *cxl_memdev_attributes[] = {
-	&dev_attr_firmware_version.attr,
-	&dev_attr_payload_max.attr,
-	&dev_attr_label_storage_size.attr,
-	NULL,
-};
-
-static struct attribute *cxl_memdev_pmem_attributes[] = {
-	&dev_attr_pmem_size.attr,
-	NULL,
-};
-
-static struct attribute *cxl_memdev_ram_attributes[] = {
-	&dev_attr_ram_size.attr,
-	NULL,
-};
-
-static struct attribute_group cxl_memdev_attribute_group = {
-	.attrs = cxl_memdev_attributes,
-};
-
-static struct attribute_group cxl_memdev_ram_attribute_group = {
-	.name = "ram",
-	.attrs = cxl_memdev_ram_attributes,
-};
-
-static struct attribute_group cxl_memdev_pmem_attribute_group = {
-	.name = "pmem",
-	.attrs = cxl_memdev_pmem_attributes,
-};
-
-static const struct attribute_group *cxl_memdev_attribute_groups[] = {
-	&cxl_memdev_attribute_group,
-	&cxl_memdev_ram_attribute_group,
-	&cxl_memdev_pmem_attribute_group,
-	NULL,
-};
-
-static const struct device_type cxl_memdev_type = {
-	.name = "cxl_memdev",
-	.release = cxl_memdev_release,
-	.devnode = cxl_memdev_devnode,
-	.groups = cxl_memdev_attribute_groups,
-};
-
-static void cxl_memdev_shutdown(struct cxl_memdev *cxlmd)
-{
-	down_write(&cxl_memdev_rwsem);
-	cxlmd->cxlm = NULL;
-	up_write(&cxl_memdev_rwsem);
-}
-
-static void cxl_memdev_unregister(void *_cxlmd)
-{
-	struct cxl_memdev *cxlmd = _cxlmd;
-	struct device *dev = &cxlmd->dev;
-
-	cdev_device_del(&cxlmd->cdev, dev);
-	cxl_memdev_shutdown(cxlmd);
-	put_device(dev);
-}
-
-static struct cxl_memdev *cxl_memdev_alloc(struct cxl_mem *cxlm)
-{
-	struct pci_dev *pdev = cxlm->pdev;
-	struct cxl_memdev *cxlmd;
-	struct device *dev;
-	struct cdev *cdev;
-	int rc;
-
-	cxlmd = kzalloc(sizeof(*cxlmd), GFP_KERNEL);
-	if (!cxlmd)
-		return ERR_PTR(-ENOMEM);
-
-	rc = ida_alloc_range(&cxl_memdev_ida, 0, CXL_MEM_MAX_DEVS, GFP_KERNEL);
-	if (rc < 0)
-		goto err;
-	cxlmd->id = rc;
-
-	dev = &cxlmd->dev;
-	device_initialize(dev);
-	dev->parent = &pdev->dev;
-	dev->bus = &cxl_bus_type;
-	dev->devt = MKDEV(cxl_mem_major, cxlmd->id);
-	dev->type = &cxl_memdev_type;
-	device_set_pm_not_required(dev);
-
-	cdev = &cxlmd->cdev;
-	cdev_init(cdev, &cxl_memdev_fops);
-	return cxlmd;
-
-err:
-	kfree(cxlmd);
-	return ERR_PTR(rc);
-}
-
-static struct cxl_memdev *devm_cxl_add_memdev(struct device *host,
-					      struct cxl_mem *cxlm)
-{
-	struct cxl_memdev *cxlmd;
-	struct device *dev;
-	struct cdev *cdev;
-	int rc;
-
-	cxlmd = cxl_memdev_alloc(cxlm);
-	if (IS_ERR(cxlmd))
-		return cxlmd;
-
-	dev = &cxlmd->dev;
-	rc = dev_set_name(dev, "mem%d", cxlmd->id);
-	if (rc)
-		goto err;
-
-	/*
-	 * Activate ioctl operations, no cxl_memdev_rwsem manipulation
-	 * needed as this is ordered with cdev_add() publishing the device.
-	 */
-	cxlmd->cxlm = cxlm;
-
-	cdev = &cxlmd->cdev;
-	rc = cdev_device_add(cdev, dev);
-	if (rc)
-		goto err;
-
-	rc = devm_add_action_or_reset(host, cxl_memdev_unregister, cxlmd);
-	if (rc)
-		return ERR_PTR(rc);
-	return cxlmd;
-
-err:
-	/*
-	 * The cdev was briefly live, shutdown any ioctl operations that
-	 * saw that state.
-	 */
-	cxl_memdev_shutdown(cxlmd);
-	put_device(dev);
-	return ERR_PTR(rc);
-}
-
 static int cxl_xfer_log(struct cxl_mem *cxlm, uuid_t *uuid, u32 size, u8 *out)
 {
 	u32 remaining = size;
@@ -1469,6 +1264,53 @@ static struct cxl_mbox_get_supported_logs *cxl_get_gsl(struct cxl_mem *cxlm)
 }
 
 /**
+ * cxl_mem_get_partition_info - Get partition info
+ * @cxlm: The device to act on
+ * @active_volatile_bytes: returned active volatile capacity
+ * @active_persistent_bytes: returned active persistent capacity
+ * @next_volatile_bytes: return next volatile capacity
+ * @next_persistent_bytes: return next persistent capacity
+ *
+ * Retrieve the current partition info for the device specified.  If not 0, the
+ * 'next' values are pending and take affect on next cold reset.
+ *
+ * Return: 0 if no error: or the result of the mailbox command.
+ *
+ * See CXL @8.2.9.5.2.1 Get Partition Info
+ */
+static int cxl_mem_get_partition_info(struct cxl_mem *cxlm,
+				      u64 *active_volatile_bytes,
+				      u64 *active_persistent_bytes,
+				      u64 *next_volatile_bytes,
+				      u64 *next_persistent_bytes)
+{
+	struct cxl_mbox_get_partition_info {
+		__le64 active_volatile_cap;
+		__le64 active_persistent_cap;
+		__le64 next_volatile_cap;
+		__le64 next_persistent_cap;
+	} __packed pi;
+	int rc;
+
+	rc = cxl_mem_mbox_send_cmd(cxlm, CXL_MBOX_OP_GET_PARTITION_INFO,
+				   NULL, 0, &pi, sizeof(pi));
+	if (rc)
+		return rc;
+
+	*active_volatile_bytes = le64_to_cpu(pi.active_volatile_cap);
+	*active_persistent_bytes = le64_to_cpu(pi.active_persistent_cap);
+	*next_volatile_bytes = le64_to_cpu(pi.next_volatile_cap);
+	*next_persistent_bytes = le64_to_cpu(pi.next_volatile_cap);
+
+	*active_volatile_bytes *= CXL_CAPACITY_MULTIPLIER;
+	*active_persistent_bytes *= CXL_CAPACITY_MULTIPLIER;
+	*next_volatile_bytes *= CXL_CAPACITY_MULTIPLIER;
+	*next_persistent_bytes *= CXL_CAPACITY_MULTIPLIER;
+
+	return 0;
+}
+
+/**
  * cxl_mem_enumerate_cmds() - Enumerate commands for a device.
  * @cxlm: The device.
  *
@@ -1564,16 +1406,27 @@ static int cxl_mem_identify(struct cxl_mem *cxlm)
 	if (rc < 0)
 		return rc;
 
-	/*
-	 * TODO: enumerate DPA map, as 'ram' and 'pmem' do not alias.
-	 * For now, only the capacity is exported in sysfs
-	 */
-	cxlm->ram_range.start = 0;
-	cxlm->ram_range.end = le64_to_cpu(id.volatile_capacity) * SZ_256M - 1;
+	cxlm->total_bytes = le64_to_cpu(id.total_capacity);
+	cxlm->total_bytes *= CXL_CAPACITY_MULTIPLIER;
+
+	cxlm->volatile_only_bytes = le64_to_cpu(id.volatile_capacity);
+	cxlm->volatile_only_bytes *= CXL_CAPACITY_MULTIPLIER;
 
-	cxlm->pmem_range.start = 0;
-	cxlm->pmem_range.end =
-		le64_to_cpu(id.persistent_capacity) * SZ_256M - 1;
+	cxlm->persistent_only_bytes = le64_to_cpu(id.persistent_capacity);
+	cxlm->persistent_only_bytes *= CXL_CAPACITY_MULTIPLIER;
+
+	cxlm->partition_align_bytes = le64_to_cpu(id.partition_align);
+	cxlm->partition_align_bytes *= CXL_CAPACITY_MULTIPLIER;
+
+	dev_dbg(&cxlm->pdev->dev, "Identify Memory Device\n"
+		"     total_bytes = %#llx\n"
+		"     volatile_only_bytes = %#llx\n"
+		"     persistent_only_bytes = %#llx\n"
+		"     partition_align_bytes = %#llx\n",
+			cxlm->total_bytes,
+			cxlm->volatile_only_bytes,
+			cxlm->persistent_only_bytes,
+			cxlm->partition_align_bytes);
 
 	cxlm->lsa_size = le32_to_cpu(id.lsa_size);
 	memcpy(cxlm->firmware_version, id.fw_revision, sizeof(id.fw_revision));
@@ -1581,6 +1434,49 @@ static int cxl_mem_identify(struct cxl_mem *cxlm)
 	return 0;
 }
 
+static int cxl_mem_create_range_info(struct cxl_mem *cxlm)
+{
+	int rc;
+
+	if (cxlm->partition_align_bytes == 0) {
+		cxlm->ram_range.start = 0;
+		cxlm->ram_range.end = cxlm->volatile_only_bytes - 1;
+		cxlm->pmem_range.start = cxlm->volatile_only_bytes;
+		cxlm->pmem_range.end = cxlm->volatile_only_bytes +
+					cxlm->persistent_only_bytes - 1;
+		return 0;
+	}
+
+	rc = cxl_mem_get_partition_info(cxlm,
+					&cxlm->active_volatile_bytes,
+					&cxlm->active_persistent_bytes,
+					&cxlm->next_volatile_bytes,
+					&cxlm->next_persistent_bytes);
+	if (rc < 0) {
+		dev_err(&cxlm->pdev->dev, "Failed to query partition information\n");
+		return rc;
+	}
+
+	dev_dbg(&cxlm->pdev->dev, "Get Partition Info\n"
+		"     active_volatile_bytes = %#llx\n"
+		"     active_persistent_bytes = %#llx\n"
+		"     next_volatile_bytes = %#llx\n"
+		"     next_persistent_bytes = %#llx\n",
+			cxlm->active_volatile_bytes,
+			cxlm->active_persistent_bytes,
+			cxlm->next_volatile_bytes,
+			cxlm->next_persistent_bytes);
+
+	cxlm->ram_range.start = 0;
+	cxlm->ram_range.end = cxlm->active_volatile_bytes - 1;
+
+	cxlm->pmem_range.start = cxlm->active_volatile_bytes;
+	cxlm->pmem_range.end = cxlm->active_volatile_bytes +
+				cxlm->active_persistent_bytes - 1;
+
+	return 0;
+}
+
 static int cxl_mem_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 {
 	struct cxl_memdev *cxlmd;
@@ -1611,7 +1507,11 @@ static int cxl_mem_probe(struct pci_dev *pdev, const struct pci_device_id *id)
 	if (rc)
 		return rc;
 
-	cxlmd = devm_cxl_add_memdev(&pdev->dev, cxlm);
+	rc = cxl_mem_create_range_info(cxlm);
+	if (rc)
+		return rc;
+
+	cxlmd = devm_cxl_add_memdev(&pdev->dev, cxlm, &cxl_memdev_fops);
 	if (IS_ERR(cxlmd))
 		return PTR_ERR(cxlmd);
 
@@ -1640,25 +1540,15 @@ static struct pci_driver cxl_mem_driver = {
 static __init int cxl_mem_init(void)
 {
 	struct dentry *mbox_debugfs;
-	dev_t devt;
 	int rc;
 
 	/* Double check the anonymous union trickery in struct cxl_regs */
 	BUILD_BUG_ON(offsetof(struct cxl_regs, memdev) !=
 		     offsetof(struct cxl_regs, device_regs.memdev));
 
-	rc = alloc_chrdev_region(&devt, 0, CXL_MEM_MAX_DEVS, "cxl");
-	if (rc)
-		return rc;
-
-	cxl_mem_major = MAJOR(devt);
-
 	rc = pci_register_driver(&cxl_mem_driver);
-	if (rc) {
-		unregister_chrdev_region(MKDEV(cxl_mem_major, 0),
-					 CXL_MEM_MAX_DEVS);
+	if (rc)
 		return rc;
-	}
 
 	cxl_debugfs = debugfs_create_dir("cxl", NULL);
 	mbox_debugfs = debugfs_create_dir("mbox", cxl_debugfs);
@@ -1672,7 +1562,6 @@ static __exit void cxl_mem_exit(void)
 {
 	debugfs_remove_recursive(cxl_debugfs);
 	pci_unregister_driver(&cxl_mem_driver);
-	unregister_chrdev_region(MKDEV(cxl_mem_major, 0), CXL_MEM_MAX_DEVS);
 }
 
 MODULE_LICENSE("GPL v2");
diff --git a/drivers/cxl/pci.h b/drivers/cxl/pci.h
index dad7a831f65f..8c1a58813816 100644
--- a/drivers/cxl/pci.h
+++ b/drivers/cxl/pci.h
@@ -25,6 +25,7 @@
 #define CXL_REGLOC_RBI_COMPONENT 1
 #define CXL_REGLOC_RBI_VIRT 2
 #define CXL_REGLOC_RBI_MEMDEV 3
+#define CXL_REGLOC_RBI_TYPES CXL_REGLOC_RBI_MEMDEV + 1
 
 #define CXL_REGLOC_ADDR_MASK GENMASK(31, 16)
 
diff --git a/drivers/cxl/pmem.c b/drivers/cxl/pmem.c
index 0088e41dd2f3..9652c3ee41e7 100644
--- a/drivers/cxl/pmem.c
+++ b/drivers/cxl/pmem.c
@@ -6,7 +6,7 @@
 #include <linux/ndctl.h>
 #include <linux/async.h>
 #include <linux/slab.h>
-#include "mem.h"
+#include "cxlmem.h"
 #include "cxl.h"
 
 /*