Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 665 insertions, 0 deletions

diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h
new file mode 100644
index 000000000..7750ccb76
--- /dev/null
+++ b/drivers/cxl/cxl.h
@@ -0,0 +1,665 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/* Copyright(c) 2020 Intel Corporation. */
+
+#ifndef __CXL_H__
+#define __CXL_H__
+
+#include <linux/libnvdimm.h>
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/log2.h>
+#include <linux/io.h>
+
+/**
+ * DOC: cxl objects
+ *
+ * The CXL core objects like ports, decoders, and regions are shared
+ * between the subsystem drivers cxl_acpi, cxl_pci, and core drivers
+ * (port-driver, region-driver, nvdimm object-drivers... etc).
+ */
+
+/* CXL 2.0 8.2.4 CXL Component Register Layout and Definition */
+#define CXL_COMPONENT_REG_BLOCK_SIZE SZ_64K
+
+/* CXL 2.0 8.2.5 CXL.cache and CXL.mem Registers*/
+#define CXL_CM_OFFSET 0x1000
+#define CXL_CM_CAP_HDR_OFFSET 0x0
+#define   CXL_CM_CAP_HDR_ID_MASK GENMASK(15, 0)
+#define     CM_CAP_HDR_CAP_ID 1
+#define   CXL_CM_CAP_HDR_VERSION_MASK GENMASK(19, 16)
+#define     CM_CAP_HDR_CAP_VERSION 1
+#define   CXL_CM_CAP_HDR_CACHE_MEM_VERSION_MASK GENMASK(23, 20)
+#define     CM_CAP_HDR_CACHE_MEM_VERSION 1
+#define   CXL_CM_CAP_HDR_ARRAY_SIZE_MASK GENMASK(31, 24)
+#define CXL_CM_CAP_PTR_MASK GENMASK(31, 20)
+
+#define   CXL_CM_CAP_CAP_ID_HDM 0x5
+#define   CXL_CM_CAP_CAP_HDM_VERSION 1
+
+/* HDM decoders CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure */
+#define CXL_HDM_DECODER_CAP_OFFSET 0x0
+#define   CXL_HDM_DECODER_COUNT_MASK GENMASK(3, 0)
+#define   CXL_HDM_DECODER_TARGET_COUNT_MASK GENMASK(7, 4)
+#define   CXL_HDM_DECODER_INTERLEAVE_11_8 BIT(8)
+#define   CXL_HDM_DECODER_INTERLEAVE_14_12 BIT(9)
+#define CXL_HDM_DECODER_CTRL_OFFSET 0x4
+#define   CXL_HDM_DECODER_ENABLE BIT(1)
+#define CXL_HDM_DECODER0_BASE_LOW_OFFSET(i) (0x20 * (i) + 0x10)
+#define CXL_HDM_DECODER0_BASE_HIGH_OFFSET(i) (0x20 * (i) + 0x14)
+#define CXL_HDM_DECODER0_SIZE_LOW_OFFSET(i) (0x20 * (i) + 0x18)
+#define CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(i) (0x20 * (i) + 0x1c)
+#define CXL_HDM_DECODER0_CTRL_OFFSET(i) (0x20 * (i) + 0x20)
+#define   CXL_HDM_DECODER0_CTRL_IG_MASK GENMASK(3, 0)
+#define   CXL_HDM_DECODER0_CTRL_IW_MASK GENMASK(7, 4)
+#define   CXL_HDM_DECODER0_CTRL_LOCK BIT(8)
+#define   CXL_HDM_DECODER0_CTRL_COMMIT BIT(9)
+#define   CXL_HDM_DECODER0_CTRL_COMMITTED BIT(10)
+#define   CXL_HDM_DECODER0_CTRL_COMMIT_ERROR BIT(11)
+#define   CXL_HDM_DECODER0_CTRL_TYPE BIT(12)
+#define CXL_HDM_DECODER0_TL_LOW(i) (0x20 * (i) + 0x24)
+#define CXL_HDM_DECODER0_TL_HIGH(i) (0x20 * (i) + 0x28)
+#define CXL_HDM_DECODER0_SKIP_LOW(i) CXL_HDM_DECODER0_TL_LOW(i)
+#define CXL_HDM_DECODER0_SKIP_HIGH(i) CXL_HDM_DECODER0_TL_HIGH(i)
+
+static inline int cxl_hdm_decoder_count(u32 cap_hdr)
+{
+	int val = FIELD_GET(CXL_HDM_DECODER_COUNT_MASK, cap_hdr);
+
+	return val ? val * 2 : 1;
+}
+
+/* Encode defined in CXL 2.0 8.2.5.12.7 HDM Decoder Control Register */
+static inline int cxl_to_granularity(u16 ig, unsigned int *val)
+{
+	if (ig > 6)
+		return -EINVAL;
+	*val = 256 << ig;
+	return 0;
+}
+
+/* Encode defined in CXL ECN "3, 6, 12 and 16-way memory Interleaving" */
+static inline int cxl_to_ways(u8 eniw, unsigned int *val)
+{
+	switch (eniw) {
+	case 0 ... 4:
+		*val = 1 << eniw;
+		break;
+	case 8 ... 10:
+		*val = 3 << (eniw - 8);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
+
+static inline int granularity_to_cxl(int g, u16 *ig)
+{
+	if (g > SZ_16K || g < 256 || !is_power_of_2(g))
+		return -EINVAL;
+	*ig = ilog2(g) - 8;
+	return 0;
+}
+
+static inline int ways_to_cxl(unsigned int ways, u8 *iw)
+{
+	if (ways > 16)
+		return -EINVAL;
+	if (is_power_of_2(ways)) {
+		*iw = ilog2(ways);
+		return 0;
+	}
+	if (ways % 3)
+		return -EINVAL;
+	ways /= 3;
+	if (!is_power_of_2(ways))
+		return -EINVAL;
+	*iw = ilog2(ways) + 8;
+	return 0;
+}
+
+/* CXL 2.0 8.2.8.1 Device Capabilities Array Register */
+#define CXLDEV_CAP_ARRAY_OFFSET 0x0
+#define   CXLDEV_CAP_ARRAY_CAP_ID 0
+#define   CXLDEV_CAP_ARRAY_ID_MASK GENMASK_ULL(15, 0)
+#define   CXLDEV_CAP_ARRAY_COUNT_MASK GENMASK_ULL(47, 32)
+/* CXL 2.0 8.2.8.2 CXL Device Capability Header Register */
+#define CXLDEV_CAP_HDR_CAP_ID_MASK GENMASK(15, 0)
+/* CXL 2.0 8.2.8.2.1 CXL Device Capabilities */
+#define CXLDEV_CAP_CAP_ID_DEVICE_STATUS 0x1
+#define CXLDEV_CAP_CAP_ID_PRIMARY_MAILBOX 0x2
+#define CXLDEV_CAP_CAP_ID_SECONDARY_MAILBOX 0x3
+#define CXLDEV_CAP_CAP_ID_MEMDEV 0x4000
+
+/* CXL 2.0 8.2.8.4 Mailbox Registers */
+#define CXLDEV_MBOX_CAPS_OFFSET 0x00
+#define   CXLDEV_MBOX_CAP_PAYLOAD_SIZE_MASK GENMASK(4, 0)
+#define CXLDEV_MBOX_CTRL_OFFSET 0x04
+#define   CXLDEV_MBOX_CTRL_DOORBELL BIT(0)
+#define CXLDEV_MBOX_CMD_OFFSET 0x08
+#define   CXLDEV_MBOX_CMD_COMMAND_OPCODE_MASK GENMASK_ULL(15, 0)
+#define   CXLDEV_MBOX_CMD_PAYLOAD_LENGTH_MASK GENMASK_ULL(36, 16)
+#define CXLDEV_MBOX_STATUS_OFFSET 0x10
+#define   CXLDEV_MBOX_STATUS_RET_CODE_MASK GENMASK_ULL(47, 32)
+#define CXLDEV_MBOX_BG_CMD_STATUS_OFFSET 0x18
+#define CXLDEV_MBOX_PAYLOAD_OFFSET 0x20
+
+/*
+ * Using struct_group() allows for per register-block-type helper routines,
+ * without requiring block-type agnostic code to include the prefix.
+ */
+struct cxl_regs {
+	/*
+	 * Common set of CXL Component register block base pointers
+	 * @hdm_decoder: CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure
+	 */
+	struct_group_tagged(cxl_component_regs, component,
+		void __iomem *hdm_decoder;
+	);
+	/*
+	 * Common set of CXL Device register block base pointers
+	 * @status: CXL 2.0 8.2.8.3 Device Status Registers
+	 * @mbox: CXL 2.0 8.2.8.4 Mailbox Registers
+	 * @memdev: CXL 2.0 8.2.8.5 Memory Device Registers
+	 */
+	struct_group_tagged(cxl_device_regs, device_regs,
+		void __iomem *status, *mbox, *memdev;
+	);
+};
+
+struct cxl_reg_map {
+	bool valid;
+	unsigned long offset;
+	unsigned long size;
+};
+
+struct cxl_component_reg_map {
+	struct cxl_reg_map hdm_decoder;
+};
+
+struct cxl_device_reg_map {
+	struct cxl_reg_map status;
+	struct cxl_reg_map mbox;
+	struct cxl_reg_map memdev;
+};
+
+/**
+ * struct cxl_register_map - DVSEC harvested register block mapping parameters
+ * @base: virtual base of the register-block-BAR + @block_offset
+ * @block_offset: offset to start of register block in @barno
+ * @reg_type: see enum cxl_regloc_type
+ * @barno: PCI BAR number containing the register block
+ * @component_map: cxl_reg_map for component registers
+ * @device_map: cxl_reg_maps for device registers
+ */
+struct cxl_register_map {
+	void __iomem *base;
+	u64 block_offset;
+	u8 reg_type;
+	u8 barno;
+	union {
+		struct cxl_component_reg_map component_map;
+		struct cxl_device_reg_map device_map;
+	};
+};
+
+void cxl_probe_component_regs(struct device *dev, void __iomem *base,
+			      struct cxl_component_reg_map *map);
+void cxl_probe_device_regs(struct device *dev, void __iomem *base,
+			   struct cxl_device_reg_map *map);
+int cxl_map_component_regs(struct pci_dev *pdev,
+			   struct cxl_component_regs *regs,
+			   struct cxl_register_map *map);
+int cxl_map_device_regs(struct pci_dev *pdev,
+			struct cxl_device_regs *regs,
+			struct cxl_register_map *map);
+
+enum cxl_regloc_type;
+int cxl_find_regblock(struct pci_dev *pdev, enum cxl_regloc_type type,
+		      struct cxl_register_map *map);
+void __iomem *devm_cxl_iomap_block(struct device *dev, resource_size_t addr,
+				   resource_size_t length);
+
+#define CXL_RESOURCE_NONE ((resource_size_t) -1)
+#define CXL_TARGET_STRLEN 20
+
+/*
+ * cxl_decoder flags that define the type of memory / devices this
+ * decoder supports as well as configuration lock status See "CXL 2.0
+ * 8.2.5.12.7 CXL HDM Decoder 0 Control Register" for details.
+ */
+#define CXL_DECODER_F_RAM   BIT(0)
+#define CXL_DECODER_F_PMEM  BIT(1)
+#define CXL_DECODER_F_TYPE2 BIT(2)
+#define CXL_DECODER_F_TYPE3 BIT(3)
+#define CXL_DECODER_F_LOCK  BIT(4)
+#define CXL_DECODER_F_ENABLE    BIT(5)
+#define CXL_DECODER_F_MASK  GENMASK(5, 0)
+
+enum cxl_decoder_type {
+       CXL_DECODER_ACCELERATOR = 2,
+       CXL_DECODER_EXPANDER = 3,
+};
+
+/*
+ * Current specification goes up to 8, double that seems a reasonable
+ * software max for the foreseeable future
+ */
+#define CXL_DECODER_MAX_INTERLEAVE 16
+
+#define CXL_DECODER_MIN_GRANULARITY 256
+
+/**
+ * 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
+ * @interleave_ways: number of cxl_dports in this decode
+ * @interleave_granularity: data stride per dport
+ * @target_type: accelerator vs expander (type2 vs type3) selector
+ * @region: currently assigned region for this decoder
+ * @flags: memory type capabilities and locking
+ * @commit: device/decoder-type specific callback to commit settings to hw
+ * @reset: device/decoder-type specific callback to reset hw settings
+*/
+struct cxl_decoder {
+	struct device dev;
+	int id;
+	struct range hpa_range;
+	int interleave_ways;
+	int interleave_granularity;
+	enum cxl_decoder_type target_type;
+	struct cxl_region *region;
+	unsigned long flags;
+	int (*commit)(struct cxl_decoder *cxld);
+	int (*reset)(struct cxl_decoder *cxld);
+};
+
+/*
+ * CXL_DECODER_DEAD prevents endpoints from being reattached to regions
+ * while cxld_unregister() is running
+ */
+enum cxl_decoder_mode {
+	CXL_DECODER_NONE,
+	CXL_DECODER_RAM,
+	CXL_DECODER_PMEM,
+	CXL_DECODER_MIXED,
+	CXL_DECODER_DEAD,
+};
+
+/**
+ * struct cxl_endpoint_decoder - Endpoint  / SPA to DPA decoder
+ * @cxld: base cxl_decoder_object
+ * @dpa_res: actively claimed DPA span of this decoder
+ * @skip: offset into @dpa_res where @cxld.hpa_range maps
+ * @mode: which memory type / access-mode-partition this decoder targets
+ * @pos: interleave position in @cxld.region
+ */
+struct cxl_endpoint_decoder {
+	struct cxl_decoder cxld;
+	struct resource *dpa_res;
+	resource_size_t skip;
+	enum cxl_decoder_mode mode;
+	int pos;
+};
+
+/**
+ * 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[];
+};
+
+
+/**
+ * struct cxl_root_decoder - Static platform CXL address decoder
+ * @res: host / parent resource for region allocations
+ * @region_id: region id for next region provisioning event
+ * @calc_hb: which host bridge covers the n'th position by granularity
+ * @cxlsd: base cxl switch decoder
+ */
+struct cxl_root_decoder {
+	struct resource *res;
+	atomic_t region_id;
+	struct cxl_dport *(*calc_hb)(struct cxl_root_decoder *cxlrd, int pos);
+	struct cxl_switch_decoder cxlsd;
+};
+
+/*
+ * enum cxl_config_state - State machine for region configuration
+ * @CXL_CONFIG_IDLE: Any sysfs attribute can be written freely
+ * @CXL_CONFIG_INTERLEAVE_ACTIVE: region size has been set, no more
+ * changes to interleave_ways or interleave_granularity
+ * @CXL_CONFIG_ACTIVE: All targets have been added the region is now
+ * active
+ * @CXL_CONFIG_RESET_PENDING: see commit_store()
+ * @CXL_CONFIG_COMMIT: Soft-config has been committed to hardware
+ */
+enum cxl_config_state {
+	CXL_CONFIG_IDLE,
+	CXL_CONFIG_INTERLEAVE_ACTIVE,
+	CXL_CONFIG_ACTIVE,
+	CXL_CONFIG_RESET_PENDING,
+	CXL_CONFIG_COMMIT,
+};
+
+/**
+ * struct cxl_region_params - region settings
+ * @state: allow the driver to lockdown further parameter changes
+ * @uuid: unique id for persistent regions
+ * @interleave_ways: number of endpoints in the region
+ * @interleave_granularity: capacity each endpoint contributes to a stripe
+ * @res: allocated iomem capacity for this region
+ * @targets: active ordered targets in current decoder configuration
+ * @nr_targets: number of targets
+ *
+ * State transitions are protected by the cxl_region_rwsem
+ */
+struct cxl_region_params {
+	enum cxl_config_state state;
+	uuid_t uuid;
+	int interleave_ways;
+	int interleave_granularity;
+	struct resource *res;
+	struct cxl_endpoint_decoder *targets[CXL_DECODER_MAX_INTERLEAVE];
+	int nr_targets;
+};
+
+/**
+ * struct cxl_region - CXL region
+ * @dev: This region's device
+ * @id: This region's id. Id is globally unique across all regions
+ * @mode: Endpoint decoder allocation / access mode
+ * @type: Endpoint decoder target type
+ * @params: active + config params for the region
+ */
+struct cxl_region {
+	struct device dev;
+	int id;
+	enum cxl_decoder_mode mode;
+	enum cxl_decoder_type type;
+	struct cxl_region_params params;
+};
+
+/**
+ * enum cxl_nvdimm_brige_state - state machine for managing bus rescans
+ * @CXL_NVB_NEW: Set at bridge create and after cxl_pmem_wq is destroyed
+ * @CXL_NVB_DEAD: Set at brige unregistration to preclude async probing
+ * @CXL_NVB_ONLINE: Target state after successful ->probe()
+ * @CXL_NVB_OFFLINE: Target state after ->remove() or failed ->probe()
+ */
+enum cxl_nvdimm_brige_state {
+	CXL_NVB_NEW,
+	CXL_NVB_DEAD,
+	CXL_NVB_ONLINE,
+	CXL_NVB_OFFLINE,
+};
+
+struct cxl_nvdimm_bridge {
+	int id;
+	struct device dev;
+	struct cxl_port *port;
+	struct nvdimm_bus *nvdimm_bus;
+	struct nvdimm_bus_descriptor nd_desc;
+	struct work_struct state_work;
+	enum cxl_nvdimm_brige_state state;
+};
+
+struct cxl_nvdimm {
+	struct device dev;
+	struct cxl_memdev *cxlmd;
+	struct cxl_nvdimm_bridge *bridge;
+	struct xarray pmem_regions;
+};
+
+struct cxl_pmem_region_mapping {
+	struct cxl_memdev *cxlmd;
+	struct cxl_nvdimm *cxl_nvd;
+	u64 start;
+	u64 size;
+	int position;
+};
+
+struct cxl_pmem_region {
+	struct device dev;
+	struct cxl_region *cxlr;
+	struct nd_region *nd_region;
+	struct cxl_nvdimm_bridge *bridge;
+	struct range hpa_range;
+	int nr_mappings;
+	struct cxl_pmem_region_mapping mapping[];
+};
+
+/**
+ * struct cxl_port - logical collection of upstream port devices and
+ *		     downstream port devices to construct a CXL memory
+ *		     decode hierarchy.
+ * @dev: this port's device
+ * @uport: PCI or platform device implementing the upstream port capability
+ * @host_bridge: Shortcut to the platform attach point for this port
+ * @id: id for port device-name
+ * @dports: cxl_dport instances referenced by decoders
+ * @endpoints: cxl_ep instances, endpoints that are a descendant of this port
+ * @regions: cxl_region_ref instances, regions mapped by this port
+ * @parent_dport: dport that points to this port in the parent
+ * @decoder_ida: allocator for decoder ids
+ * @nr_dports: number of entries in @dports
+ * @hdm_end: track last allocated HDM decoder instance for allocation ordering
+ * @commit_end: cursor to track highest committed decoder for commit ordering
+ * @component_reg_phys: component register capability base address (optional)
+ * @dead: last ep has been removed, force port re-creation
+ * @depth: How deep this port is relative to the root. depth 0 is the root.
+ * @cdat: Cached CDAT data
+ * @cdat_available: Should a CDAT attribute be available in sysfs
+ */
+struct cxl_port {
+	struct device dev;
+	struct device *uport;
+	struct device *host_bridge;
+	int id;
+	struct xarray dports;
+	struct xarray endpoints;
+	struct xarray regions;
+	struct cxl_dport *parent_dport;
+	struct ida decoder_ida;
+	int nr_dports;
+	int hdm_end;
+	int commit_end;
+	resource_size_t component_reg_phys;
+	bool dead;
+	unsigned int depth;
+	struct cxl_cdat {
+		void *table;
+		size_t length;
+	} cdat;
+	bool cdat_available;
+};
+
+static inline struct cxl_dport *
+cxl_find_dport_by_dev(struct cxl_port *port, const struct device *dport_dev)
+{
+	return xa_load(&port->dports, (unsigned long)dport_dev);
+}
+
+/**
+ * struct cxl_dport - CXL downstream port
+ * @dport: PCI bridge or firmware device representing the downstream link
+ * @port_id: unique hardware identifier for dport in decoder target list
+ * @component_reg_phys: downstream port component registers
+ * @port: reference to cxl_port that contains this downstream port
+ */
+struct cxl_dport {
+	struct device *dport;
+	int port_id;
+	resource_size_t component_reg_phys;
+	struct cxl_port *port;
+};
+
+/**
+ * struct cxl_ep - track an endpoint's interest in a port
+ * @ep: device that hosts a generic CXL endpoint (expander or accelerator)
+ * @dport: which dport routes to this endpoint on @port
+ * @next: cxl switch port across the link attached to @dport NULL if
+ *	  attached to an endpoint
+ */
+struct cxl_ep {
+	struct device *ep;
+	struct cxl_dport *dport;
+	struct cxl_port *next;
+};
+
+/**
+ * struct cxl_region_ref - track a region's interest in a port
+ * @port: point in topology to install this reference
+ * @decoder: decoder assigned for @region in @port
+ * @region: region for this reference
+ * @endpoints: cxl_ep references for region members beneath @port
+ * @nr_targets_set: track how many targets have been programmed during setup
+ * @nr_eps: number of endpoints beneath @port
+ * @nr_targets: number of distinct targets needed to reach @nr_eps
+ */
+struct cxl_region_ref {
+	struct cxl_port *port;
+	struct cxl_decoder *decoder;
+	struct cxl_region *region;
+	struct xarray endpoints;
+	int nr_targets_set;
+	int nr_eps;
+	int nr_targets;
+};
+
+/*
+ * The platform firmware device hosting the root is also the top of the
+ * CXL port topology. All other CXL ports have another CXL port as their
+ * parent and their ->uport / host device is out-of-line of the port
+ * ancestry.
+ */
+static inline bool is_cxl_root(struct cxl_port *port)
+{
+	return port->uport == port->dev.parent;
+}
+
+bool is_cxl_port(struct device *dev);
+struct cxl_port *to_cxl_port(struct device *dev);
+struct pci_bus;
+int devm_cxl_register_pci_bus(struct device *host, struct device *uport,
+			      struct pci_bus *bus);
+struct pci_bus *cxl_port_to_pci_bus(struct cxl_port *port);
+struct cxl_port *devm_cxl_add_port(struct device *host, struct device *uport,
+				   resource_size_t component_reg_phys,
+				   struct cxl_dport *parent_dport);
+struct cxl_port *find_cxl_root(struct device *dev);
+int devm_cxl_enumerate_ports(struct cxl_memdev *cxlmd);
+int cxl_bus_rescan(void);
+struct cxl_port *cxl_mem_find_port(struct cxl_memdev *cxlmd,
+				   struct cxl_dport **dport);
+bool schedule_cxl_memdev_detach(struct cxl_memdev *cxlmd);
+
+struct cxl_dport *devm_cxl_add_dport(struct cxl_port *port,
+				     struct device *dport, int port_id,
+				     resource_size_t component_reg_phys);
+
+struct cxl_decoder *to_cxl_decoder(struct device *dev);
+struct cxl_root_decoder *to_cxl_root_decoder(struct device *dev);
+struct cxl_switch_decoder *to_cxl_switch_decoder(struct device *dev);
+struct cxl_endpoint_decoder *to_cxl_endpoint_decoder(struct device *dev);
+bool is_root_decoder(struct device *dev);
+bool is_switch_decoder(struct device *dev);
+bool is_endpoint_decoder(struct device *dev);
+struct cxl_root_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_endpoint_decoder *cxl_endpoint_decoder_alloc(struct cxl_port *port);
+int cxl_decoder_add_locked(struct cxl_decoder *cxld, int *target_map);
+int cxl_decoder_autoremove(struct device *host, struct cxl_decoder *cxld);
+int cxl_endpoint_autoremove(struct cxl_memdev *cxlmd, struct cxl_port *endpoint);
+
+struct cxl_hdm;
+struct cxl_hdm *devm_cxl_setup_hdm(struct cxl_port *port);
+int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm);
+int devm_cxl_add_passthrough_decoder(struct cxl_port *port);
+
+bool is_cxl_region(struct device *dev);
+
+extern struct bus_type cxl_bus_type;
+
+struct cxl_driver {
+	const char *name;
+	int (*probe)(struct device *dev);
+	void (*remove)(struct device *dev);
+	struct device_driver drv;
+	int id;
+};
+
+static inline struct cxl_driver *to_cxl_drv(struct device_driver *drv)
+{
+	return container_of(drv, struct cxl_driver, drv);
+}
+
+int __cxl_driver_register(struct cxl_driver *cxl_drv, struct module *owner,
+			  const char *modname);
+#define cxl_driver_register(x) __cxl_driver_register(x, THIS_MODULE, KBUILD_MODNAME)
+void cxl_driver_unregister(struct cxl_driver *cxl_drv);
+
+#define module_cxl_driver(__cxl_driver) \
+	module_driver(__cxl_driver, cxl_driver_register, cxl_driver_unregister)
+
+#define CXL_DEVICE_NVDIMM_BRIDGE	1
+#define CXL_DEVICE_NVDIMM		2
+#define CXL_DEVICE_PORT			3
+#define CXL_DEVICE_ROOT			4
+#define CXL_DEVICE_MEMORY_EXPANDER	5
+#define CXL_DEVICE_REGION		6
+#define CXL_DEVICE_PMEM_REGION		7
+
+#define MODULE_ALIAS_CXL(type) MODULE_ALIAS("cxl:t" __stringify(type) "*")
+#define CXL_MODALIAS_FMT "cxl:t%d"
+
+struct cxl_nvdimm_bridge *to_cxl_nvdimm_bridge(struct device *dev);
+struct cxl_nvdimm_bridge *devm_cxl_add_nvdimm_bridge(struct device *host,
+						     struct cxl_port *port);
+struct cxl_nvdimm *to_cxl_nvdimm(struct device *dev);
+bool is_cxl_nvdimm(struct device *dev);
+bool is_cxl_nvdimm_bridge(struct device *dev);
+int devm_cxl_add_nvdimm(struct device *host, struct cxl_memdev *cxlmd);
+struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct device *dev);
+
+#ifdef CONFIG_CXL_REGION
+bool is_cxl_pmem_region(struct device *dev);
+struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev);
+#else
+static inline bool is_cxl_pmem_region(struct device *dev)
+{
+	return false;
+}
+static inline struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev)
+{
+	return NULL;
+}
+#endif
+
+/*
+ * Unit test builds overrides this to __weak, find the 'strong' version
+ * of these symbols in tools/testing/cxl/.
+ */
+#ifndef __mock
+#define __mock static
+#endif
+
+#endif /* __CXL_H__ */