xref: /openbmc/linux/drivers/cxl/cxl.h (revision bbb774d9)
1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /* Copyright(c) 2020 Intel Corporation. */
3 
4 #ifndef __CXL_H__
5 #define __CXL_H__
6 
7 #include <linux/libnvdimm.h>
8 #include <linux/bitfield.h>
9 #include <linux/bitops.h>
10 #include <linux/log2.h>
11 #include <linux/io.h>
12 
13 /**
14  * DOC: cxl objects
15  *
16  * The CXL core objects like ports, decoders, and regions are shared
17  * between the subsystem drivers cxl_acpi, cxl_pci, and core drivers
18  * (port-driver, region-driver, nvdimm object-drivers... etc).
19  */
20 
21 /* CXL 2.0 8.2.4 CXL Component Register Layout and Definition */
22 #define CXL_COMPONENT_REG_BLOCK_SIZE SZ_64K
23 
24 /* CXL 2.0 8.2.5 CXL.cache and CXL.mem Registers*/
25 #define CXL_CM_OFFSET 0x1000
26 #define CXL_CM_CAP_HDR_OFFSET 0x0
27 #define   CXL_CM_CAP_HDR_ID_MASK GENMASK(15, 0)
28 #define     CM_CAP_HDR_CAP_ID 1
29 #define   CXL_CM_CAP_HDR_VERSION_MASK GENMASK(19, 16)
30 #define     CM_CAP_HDR_CAP_VERSION 1
31 #define   CXL_CM_CAP_HDR_CACHE_MEM_VERSION_MASK GENMASK(23, 20)
32 #define     CM_CAP_HDR_CACHE_MEM_VERSION 1
33 #define   CXL_CM_CAP_HDR_ARRAY_SIZE_MASK GENMASK(31, 24)
34 #define CXL_CM_CAP_PTR_MASK GENMASK(31, 20)
35 
36 #define   CXL_CM_CAP_CAP_ID_HDM 0x5
37 #define   CXL_CM_CAP_CAP_HDM_VERSION 1
38 
39 /* HDM decoders CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure */
40 #define CXL_HDM_DECODER_CAP_OFFSET 0x0
41 #define   CXL_HDM_DECODER_COUNT_MASK GENMASK(3, 0)
42 #define   CXL_HDM_DECODER_TARGET_COUNT_MASK GENMASK(7, 4)
43 #define   CXL_HDM_DECODER_INTERLEAVE_11_8 BIT(8)
44 #define   CXL_HDM_DECODER_INTERLEAVE_14_12 BIT(9)
45 #define CXL_HDM_DECODER_CTRL_OFFSET 0x4
46 #define   CXL_HDM_DECODER_ENABLE BIT(1)
47 #define CXL_HDM_DECODER0_BASE_LOW_OFFSET(i) (0x20 * (i) + 0x10)
48 #define CXL_HDM_DECODER0_BASE_HIGH_OFFSET(i) (0x20 * (i) + 0x14)
49 #define CXL_HDM_DECODER0_SIZE_LOW_OFFSET(i) (0x20 * (i) + 0x18)
50 #define CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(i) (0x20 * (i) + 0x1c)
51 #define CXL_HDM_DECODER0_CTRL_OFFSET(i) (0x20 * (i) + 0x20)
52 #define   CXL_HDM_DECODER0_CTRL_IG_MASK GENMASK(3, 0)
53 #define   CXL_HDM_DECODER0_CTRL_IW_MASK GENMASK(7, 4)
54 #define   CXL_HDM_DECODER0_CTRL_LOCK BIT(8)
55 #define   CXL_HDM_DECODER0_CTRL_COMMIT BIT(9)
56 #define   CXL_HDM_DECODER0_CTRL_COMMITTED BIT(10)
57 #define   CXL_HDM_DECODER0_CTRL_COMMIT_ERROR BIT(11)
58 #define   CXL_HDM_DECODER0_CTRL_TYPE BIT(12)
59 #define CXL_HDM_DECODER0_TL_LOW(i) (0x20 * (i) + 0x24)
60 #define CXL_HDM_DECODER0_TL_HIGH(i) (0x20 * (i) + 0x28)
61 #define CXL_HDM_DECODER0_SKIP_LOW(i) CXL_HDM_DECODER0_TL_LOW(i)
62 #define CXL_HDM_DECODER0_SKIP_HIGH(i) CXL_HDM_DECODER0_TL_HIGH(i)
63 
64 static inline int cxl_hdm_decoder_count(u32 cap_hdr)
65 {
66 	int val = FIELD_GET(CXL_HDM_DECODER_COUNT_MASK, cap_hdr);
67 
68 	return val ? val * 2 : 1;
69 }
70 
71 /* Encode defined in CXL 2.0 8.2.5.12.7 HDM Decoder Control Register */
72 static inline int cxl_to_granularity(u16 ig, unsigned int *val)
73 {
74 	if (ig > 6)
75 		return -EINVAL;
76 	*val = 256 << ig;
77 	return 0;
78 }
79 
80 /* Encode defined in CXL ECN "3, 6, 12 and 16-way memory Interleaving" */
81 static inline int cxl_to_ways(u8 eniw, unsigned int *val)
82 {
83 	switch (eniw) {
84 	case 0 ... 4:
85 		*val = 1 << eniw;
86 		break;
87 	case 8 ... 10:
88 		*val = 3 << (eniw - 8);
89 		break;
90 	default:
91 		return -EINVAL;
92 	}
93 
94 	return 0;
95 }
96 
97 static inline int granularity_to_cxl(int g, u16 *ig)
98 {
99 	if (g > SZ_16K || g < 256 || !is_power_of_2(g))
100 		return -EINVAL;
101 	*ig = ilog2(g) - 8;
102 	return 0;
103 }
104 
105 static inline int ways_to_cxl(unsigned int ways, u8 *iw)
106 {
107 	if (ways > 16)
108 		return -EINVAL;
109 	if (is_power_of_2(ways)) {
110 		*iw = ilog2(ways);
111 		return 0;
112 	}
113 	if (ways % 3)
114 		return -EINVAL;
115 	ways /= 3;
116 	if (!is_power_of_2(ways))
117 		return -EINVAL;
118 	*iw = ilog2(ways) + 8;
119 	return 0;
120 }
121 
122 /* CXL 2.0 8.2.8.1 Device Capabilities Array Register */
123 #define CXLDEV_CAP_ARRAY_OFFSET 0x0
124 #define   CXLDEV_CAP_ARRAY_CAP_ID 0
125 #define   CXLDEV_CAP_ARRAY_ID_MASK GENMASK_ULL(15, 0)
126 #define   CXLDEV_CAP_ARRAY_COUNT_MASK GENMASK_ULL(47, 32)
127 /* CXL 2.0 8.2.8.2 CXL Device Capability Header Register */
128 #define CXLDEV_CAP_HDR_CAP_ID_MASK GENMASK(15, 0)
129 /* CXL 2.0 8.2.8.2.1 CXL Device Capabilities */
130 #define CXLDEV_CAP_CAP_ID_DEVICE_STATUS 0x1
131 #define CXLDEV_CAP_CAP_ID_PRIMARY_MAILBOX 0x2
132 #define CXLDEV_CAP_CAP_ID_SECONDARY_MAILBOX 0x3
133 #define CXLDEV_CAP_CAP_ID_MEMDEV 0x4000
134 
135 /* CXL 2.0 8.2.8.4 Mailbox Registers */
136 #define CXLDEV_MBOX_CAPS_OFFSET 0x00
137 #define   CXLDEV_MBOX_CAP_PAYLOAD_SIZE_MASK GENMASK(4, 0)
138 #define CXLDEV_MBOX_CTRL_OFFSET 0x04
139 #define   CXLDEV_MBOX_CTRL_DOORBELL BIT(0)
140 #define CXLDEV_MBOX_CMD_OFFSET 0x08
141 #define   CXLDEV_MBOX_CMD_COMMAND_OPCODE_MASK GENMASK_ULL(15, 0)
142 #define   CXLDEV_MBOX_CMD_PAYLOAD_LENGTH_MASK GENMASK_ULL(36, 16)
143 #define CXLDEV_MBOX_STATUS_OFFSET 0x10
144 #define   CXLDEV_MBOX_STATUS_RET_CODE_MASK GENMASK_ULL(47, 32)
145 #define CXLDEV_MBOX_BG_CMD_STATUS_OFFSET 0x18
146 #define CXLDEV_MBOX_PAYLOAD_OFFSET 0x20
147 
148 /*
149  * Using struct_group() allows for per register-block-type helper routines,
150  * without requiring block-type agnostic code to include the prefix.
151  */
152 struct cxl_regs {
153 	/*
154 	 * Common set of CXL Component register block base pointers
155 	 * @hdm_decoder: CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure
156 	 */
157 	struct_group_tagged(cxl_component_regs, component,
158 		void __iomem *hdm_decoder;
159 	);
160 	/*
161 	 * Common set of CXL Device register block base pointers
162 	 * @status: CXL 2.0 8.2.8.3 Device Status Registers
163 	 * @mbox: CXL 2.0 8.2.8.4 Mailbox Registers
164 	 * @memdev: CXL 2.0 8.2.8.5 Memory Device Registers
165 	 */
166 	struct_group_tagged(cxl_device_regs, device_regs,
167 		void __iomem *status, *mbox, *memdev;
168 	);
169 };
170 
171 struct cxl_reg_map {
172 	bool valid;
173 	unsigned long offset;
174 	unsigned long size;
175 };
176 
177 struct cxl_component_reg_map {
178 	struct cxl_reg_map hdm_decoder;
179 };
180 
181 struct cxl_device_reg_map {
182 	struct cxl_reg_map status;
183 	struct cxl_reg_map mbox;
184 	struct cxl_reg_map memdev;
185 };
186 
187 /**
188  * struct cxl_register_map - DVSEC harvested register block mapping parameters
189  * @base: virtual base of the register-block-BAR + @block_offset
190  * @block_offset: offset to start of register block in @barno
191  * @reg_type: see enum cxl_regloc_type
192  * @barno: PCI BAR number containing the register block
193  * @component_map: cxl_reg_map for component registers
194  * @device_map: cxl_reg_maps for device registers
195  */
196 struct cxl_register_map {
197 	void __iomem *base;
198 	u64 block_offset;
199 	u8 reg_type;
200 	u8 barno;
201 	union {
202 		struct cxl_component_reg_map component_map;
203 		struct cxl_device_reg_map device_map;
204 	};
205 };
206 
207 void cxl_probe_component_regs(struct device *dev, void __iomem *base,
208 			      struct cxl_component_reg_map *map);
209 void cxl_probe_device_regs(struct device *dev, void __iomem *base,
210 			   struct cxl_device_reg_map *map);
211 int cxl_map_component_regs(struct pci_dev *pdev,
212 			   struct cxl_component_regs *regs,
213 			   struct cxl_register_map *map);
214 int cxl_map_device_regs(struct pci_dev *pdev,
215 			struct cxl_device_regs *regs,
216 			struct cxl_register_map *map);
217 
218 enum cxl_regloc_type;
219 int cxl_find_regblock(struct pci_dev *pdev, enum cxl_regloc_type type,
220 		      struct cxl_register_map *map);
221 void __iomem *devm_cxl_iomap_block(struct device *dev, resource_size_t addr,
222 				   resource_size_t length);
223 
224 #define CXL_RESOURCE_NONE ((resource_size_t) -1)
225 #define CXL_TARGET_STRLEN 20
226 
227 /*
228  * cxl_decoder flags that define the type of memory / devices this
229  * decoder supports as well as configuration lock status See "CXL 2.0
230  * 8.2.5.12.7 CXL HDM Decoder 0 Control Register" for details.
231  */
232 #define CXL_DECODER_F_RAM   BIT(0)
233 #define CXL_DECODER_F_PMEM  BIT(1)
234 #define CXL_DECODER_F_TYPE2 BIT(2)
235 #define CXL_DECODER_F_TYPE3 BIT(3)
236 #define CXL_DECODER_F_LOCK  BIT(4)
237 #define CXL_DECODER_F_ENABLE    BIT(5)
238 #define CXL_DECODER_F_MASK  GENMASK(5, 0)
239 
240 enum cxl_decoder_type {
241        CXL_DECODER_ACCELERATOR = 2,
242        CXL_DECODER_EXPANDER = 3,
243 };
244 
245 /*
246  * Current specification goes up to 8, double that seems a reasonable
247  * software max for the foreseeable future
248  */
249 #define CXL_DECODER_MAX_INTERLEAVE 16
250 
251 #define CXL_DECODER_MIN_GRANULARITY 256
252 
253 /**
254  * struct cxl_decoder - Common CXL HDM Decoder Attributes
255  * @dev: this decoder's device
256  * @id: kernel device name id
257  * @hpa_range: Host physical address range mapped by this decoder
258  * @interleave_ways: number of cxl_dports in this decode
259  * @interleave_granularity: data stride per dport
260  * @target_type: accelerator vs expander (type2 vs type3) selector
261  * @region: currently assigned region for this decoder
262  * @flags: memory type capabilities and locking
263  * @commit: device/decoder-type specific callback to commit settings to hw
264  * @reset: device/decoder-type specific callback to reset hw settings
265 */
266 struct cxl_decoder {
267 	struct device dev;
268 	int id;
269 	struct range hpa_range;
270 	int interleave_ways;
271 	int interleave_granularity;
272 	enum cxl_decoder_type target_type;
273 	struct cxl_region *region;
274 	unsigned long flags;
275 	int (*commit)(struct cxl_decoder *cxld);
276 	int (*reset)(struct cxl_decoder *cxld);
277 };
278 
279 /*
280  * CXL_DECODER_DEAD prevents endpoints from being reattached to regions
281  * while cxld_unregister() is running
282  */
283 enum cxl_decoder_mode {
284 	CXL_DECODER_NONE,
285 	CXL_DECODER_RAM,
286 	CXL_DECODER_PMEM,
287 	CXL_DECODER_MIXED,
288 	CXL_DECODER_DEAD,
289 };
290 
291 /**
292  * struct cxl_endpoint_decoder - Endpoint  / SPA to DPA decoder
293  * @cxld: base cxl_decoder_object
294  * @dpa_res: actively claimed DPA span of this decoder
295  * @skip: offset into @dpa_res where @cxld.hpa_range maps
296  * @mode: which memory type / access-mode-partition this decoder targets
297  * @pos: interleave position in @cxld.region
298  */
299 struct cxl_endpoint_decoder {
300 	struct cxl_decoder cxld;
301 	struct resource *dpa_res;
302 	resource_size_t skip;
303 	enum cxl_decoder_mode mode;
304 	int pos;
305 };
306 
307 /**
308  * struct cxl_switch_decoder - Switch specific CXL HDM Decoder
309  * @cxld: base cxl_decoder object
310  * @target_lock: coordinate coherent reads of the target list
311  * @nr_targets: number of elements in @target
312  * @target: active ordered target list in current decoder configuration
313  *
314  * The 'switch' decoder type represents the decoder instances of cxl_port's that
315  * route from the root of a CXL memory decode topology to the endpoints. They
316  * come in two flavors, root-level decoders, statically defined by platform
317  * firmware, and mid-level decoders, where interleave-granularity,
318  * interleave-width, and the target list are mutable.
319  */
320 struct cxl_switch_decoder {
321 	struct cxl_decoder cxld;
322 	seqlock_t target_lock;
323 	int nr_targets;
324 	struct cxl_dport *target[];
325 };
326 
327 
328 /**
329  * struct cxl_root_decoder - Static platform CXL address decoder
330  * @res: host / parent resource for region allocations
331  * @region_id: region id for next region provisioning event
332  * @calc_hb: which host bridge covers the n'th position by granularity
333  * @cxlsd: base cxl switch decoder
334  */
335 struct cxl_root_decoder {
336 	struct resource *res;
337 	atomic_t region_id;
338 	struct cxl_dport *(*calc_hb)(struct cxl_root_decoder *cxlrd, int pos);
339 	struct cxl_switch_decoder cxlsd;
340 };
341 
342 /*
343  * enum cxl_config_state - State machine for region configuration
344  * @CXL_CONFIG_IDLE: Any sysfs attribute can be written freely
345  * @CXL_CONFIG_INTERLEAVE_ACTIVE: region size has been set, no more
346  * changes to interleave_ways or interleave_granularity
347  * @CXL_CONFIG_ACTIVE: All targets have been added the region is now
348  * active
349  * @CXL_CONFIG_RESET_PENDING: see commit_store()
350  * @CXL_CONFIG_COMMIT: Soft-config has been committed to hardware
351  */
352 enum cxl_config_state {
353 	CXL_CONFIG_IDLE,
354 	CXL_CONFIG_INTERLEAVE_ACTIVE,
355 	CXL_CONFIG_ACTIVE,
356 	CXL_CONFIG_RESET_PENDING,
357 	CXL_CONFIG_COMMIT,
358 };
359 
360 /**
361  * struct cxl_region_params - region settings
362  * @state: allow the driver to lockdown further parameter changes
363  * @uuid: unique id for persistent regions
364  * @interleave_ways: number of endpoints in the region
365  * @interleave_granularity: capacity each endpoint contributes to a stripe
366  * @res: allocated iomem capacity for this region
367  * @targets: active ordered targets in current decoder configuration
368  * @nr_targets: number of targets
369  *
370  * State transitions are protected by the cxl_region_rwsem
371  */
372 struct cxl_region_params {
373 	enum cxl_config_state state;
374 	uuid_t uuid;
375 	int interleave_ways;
376 	int interleave_granularity;
377 	struct resource *res;
378 	struct cxl_endpoint_decoder *targets[CXL_DECODER_MAX_INTERLEAVE];
379 	int nr_targets;
380 };
381 
382 /**
383  * struct cxl_region - CXL region
384  * @dev: This region's device
385  * @id: This region's id. Id is globally unique across all regions
386  * @mode: Endpoint decoder allocation / access mode
387  * @type: Endpoint decoder target type
388  * @params: active + config params for the region
389  */
390 struct cxl_region {
391 	struct device dev;
392 	int id;
393 	enum cxl_decoder_mode mode;
394 	enum cxl_decoder_type type;
395 	struct cxl_region_params params;
396 };
397 
398 /**
399  * enum cxl_nvdimm_brige_state - state machine for managing bus rescans
400  * @CXL_NVB_NEW: Set at bridge create and after cxl_pmem_wq is destroyed
401  * @CXL_NVB_DEAD: Set at brige unregistration to preclude async probing
402  * @CXL_NVB_ONLINE: Target state after successful ->probe()
403  * @CXL_NVB_OFFLINE: Target state after ->remove() or failed ->probe()
404  */
405 enum cxl_nvdimm_brige_state {
406 	CXL_NVB_NEW,
407 	CXL_NVB_DEAD,
408 	CXL_NVB_ONLINE,
409 	CXL_NVB_OFFLINE,
410 };
411 
412 struct cxl_nvdimm_bridge {
413 	int id;
414 	struct device dev;
415 	struct cxl_port *port;
416 	struct nvdimm_bus *nvdimm_bus;
417 	struct nvdimm_bus_descriptor nd_desc;
418 	struct work_struct state_work;
419 	enum cxl_nvdimm_brige_state state;
420 };
421 
422 struct cxl_nvdimm {
423 	struct device dev;
424 	struct cxl_memdev *cxlmd;
425 	struct cxl_nvdimm_bridge *bridge;
426 	struct cxl_pmem_region *region;
427 };
428 
429 struct cxl_pmem_region_mapping {
430 	struct cxl_memdev *cxlmd;
431 	struct cxl_nvdimm *cxl_nvd;
432 	u64 start;
433 	u64 size;
434 	int position;
435 };
436 
437 struct cxl_pmem_region {
438 	struct device dev;
439 	struct cxl_region *cxlr;
440 	struct nd_region *nd_region;
441 	struct cxl_nvdimm_bridge *bridge;
442 	struct range hpa_range;
443 	int nr_mappings;
444 	struct cxl_pmem_region_mapping mapping[];
445 };
446 
447 /**
448  * struct cxl_port - logical collection of upstream port devices and
449  *		     downstream port devices to construct a CXL memory
450  *		     decode hierarchy.
451  * @dev: this port's device
452  * @uport: PCI or platform device implementing the upstream port capability
453  * @host_bridge: Shortcut to the platform attach point for this port
454  * @id: id for port device-name
455  * @dports: cxl_dport instances referenced by decoders
456  * @endpoints: cxl_ep instances, endpoints that are a descendant of this port
457  * @regions: cxl_region_ref instances, regions mapped by this port
458  * @parent_dport: dport that points to this port in the parent
459  * @decoder_ida: allocator for decoder ids
460  * @hdm_end: track last allocated HDM decoder instance for allocation ordering
461  * @commit_end: cursor to track highest committed decoder for commit ordering
462  * @component_reg_phys: component register capability base address (optional)
463  * @dead: last ep has been removed, force port re-creation
464  * @depth: How deep this port is relative to the root. depth 0 is the root.
465  * @cdat: Cached CDAT data
466  * @cdat_available: Should a CDAT attribute be available in sysfs
467  */
468 struct cxl_port {
469 	struct device dev;
470 	struct device *uport;
471 	struct device *host_bridge;
472 	int id;
473 	struct xarray dports;
474 	struct xarray endpoints;
475 	struct xarray regions;
476 	struct cxl_dport *parent_dport;
477 	struct ida decoder_ida;
478 	int hdm_end;
479 	int commit_end;
480 	resource_size_t component_reg_phys;
481 	bool dead;
482 	unsigned int depth;
483 	struct cxl_cdat {
484 		void *table;
485 		size_t length;
486 	} cdat;
487 	bool cdat_available;
488 };
489 
490 static inline struct cxl_dport *
491 cxl_find_dport_by_dev(struct cxl_port *port, const struct device *dport_dev)
492 {
493 	return xa_load(&port->dports, (unsigned long)dport_dev);
494 }
495 
496 /**
497  * struct cxl_dport - CXL downstream port
498  * @dport: PCI bridge or firmware device representing the downstream link
499  * @port_id: unique hardware identifier for dport in decoder target list
500  * @component_reg_phys: downstream port component registers
501  * @port: reference to cxl_port that contains this downstream port
502  */
503 struct cxl_dport {
504 	struct device *dport;
505 	int port_id;
506 	resource_size_t component_reg_phys;
507 	struct cxl_port *port;
508 };
509 
510 /**
511  * struct cxl_ep - track an endpoint's interest in a port
512  * @ep: device that hosts a generic CXL endpoint (expander or accelerator)
513  * @dport: which dport routes to this endpoint on @port
514  * @next: cxl switch port across the link attached to @dport NULL if
515  *	  attached to an endpoint
516  */
517 struct cxl_ep {
518 	struct device *ep;
519 	struct cxl_dport *dport;
520 	struct cxl_port *next;
521 };
522 
523 /**
524  * struct cxl_region_ref - track a region's interest in a port
525  * @port: point in topology to install this reference
526  * @decoder: decoder assigned for @region in @port
527  * @region: region for this reference
528  * @endpoints: cxl_ep references for region members beneath @port
529  * @nr_targets_set: track how many targets have been programmed during setup
530  * @nr_eps: number of endpoints beneath @port
531  * @nr_targets: number of distinct targets needed to reach @nr_eps
532  */
533 struct cxl_region_ref {
534 	struct cxl_port *port;
535 	struct cxl_decoder *decoder;
536 	struct cxl_region *region;
537 	struct xarray endpoints;
538 	int nr_targets_set;
539 	int nr_eps;
540 	int nr_targets;
541 };
542 
543 /*
544  * The platform firmware device hosting the root is also the top of the
545  * CXL port topology. All other CXL ports have another CXL port as their
546  * parent and their ->uport / host device is out-of-line of the port
547  * ancestry.
548  */
549 static inline bool is_cxl_root(struct cxl_port *port)
550 {
551 	return port->uport == port->dev.parent;
552 }
553 
554 bool is_cxl_port(struct device *dev);
555 struct cxl_port *to_cxl_port(struct device *dev);
556 struct pci_bus;
557 int devm_cxl_register_pci_bus(struct device *host, struct device *uport,
558 			      struct pci_bus *bus);
559 struct pci_bus *cxl_port_to_pci_bus(struct cxl_port *port);
560 struct cxl_port *devm_cxl_add_port(struct device *host, struct device *uport,
561 				   resource_size_t component_reg_phys,
562 				   struct cxl_dport *parent_dport);
563 int devm_cxl_add_endpoint(struct cxl_memdev *cxlmd,
564 			  struct cxl_dport *parent_dport);
565 struct cxl_port *find_cxl_root(struct device *dev);
566 int devm_cxl_enumerate_ports(struct cxl_memdev *cxlmd);
567 int cxl_bus_rescan(void);
568 struct cxl_port *cxl_mem_find_port(struct cxl_memdev *cxlmd,
569 				   struct cxl_dport **dport);
570 bool schedule_cxl_memdev_detach(struct cxl_memdev *cxlmd);
571 
572 struct cxl_dport *devm_cxl_add_dport(struct cxl_port *port,
573 				     struct device *dport, int port_id,
574 				     resource_size_t component_reg_phys);
575 
576 struct cxl_decoder *to_cxl_decoder(struct device *dev);
577 struct cxl_root_decoder *to_cxl_root_decoder(struct device *dev);
578 struct cxl_endpoint_decoder *to_cxl_endpoint_decoder(struct device *dev);
579 bool is_root_decoder(struct device *dev);
580 bool is_endpoint_decoder(struct device *dev);
581 struct cxl_root_decoder *cxl_root_decoder_alloc(struct cxl_port *port,
582 						unsigned int nr_targets);
583 struct cxl_switch_decoder *cxl_switch_decoder_alloc(struct cxl_port *port,
584 						    unsigned int nr_targets);
585 int cxl_decoder_add(struct cxl_decoder *cxld, int *target_map);
586 struct cxl_endpoint_decoder *cxl_endpoint_decoder_alloc(struct cxl_port *port);
587 int cxl_decoder_add_locked(struct cxl_decoder *cxld, int *target_map);
588 int cxl_decoder_autoremove(struct device *host, struct cxl_decoder *cxld);
589 int cxl_endpoint_autoremove(struct cxl_memdev *cxlmd, struct cxl_port *endpoint);
590 
591 struct cxl_hdm;
592 struct cxl_hdm *devm_cxl_setup_hdm(struct cxl_port *port);
593 int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm);
594 int devm_cxl_add_passthrough_decoder(struct cxl_port *port);
595 
596 bool is_cxl_region(struct device *dev);
597 
598 extern struct bus_type cxl_bus_type;
599 
600 struct cxl_driver {
601 	const char *name;
602 	int (*probe)(struct device *dev);
603 	void (*remove)(struct device *dev);
604 	struct device_driver drv;
605 	int id;
606 };
607 
608 static inline struct cxl_driver *to_cxl_drv(struct device_driver *drv)
609 {
610 	return container_of(drv, struct cxl_driver, drv);
611 }
612 
613 int __cxl_driver_register(struct cxl_driver *cxl_drv, struct module *owner,
614 			  const char *modname);
615 #define cxl_driver_register(x) __cxl_driver_register(x, THIS_MODULE, KBUILD_MODNAME)
616 void cxl_driver_unregister(struct cxl_driver *cxl_drv);
617 
618 #define module_cxl_driver(__cxl_driver) \
619 	module_driver(__cxl_driver, cxl_driver_register, cxl_driver_unregister)
620 
621 #define CXL_DEVICE_NVDIMM_BRIDGE	1
622 #define CXL_DEVICE_NVDIMM		2
623 #define CXL_DEVICE_PORT			3
624 #define CXL_DEVICE_ROOT			4
625 #define CXL_DEVICE_MEMORY_EXPANDER	5
626 #define CXL_DEVICE_REGION		6
627 #define CXL_DEVICE_PMEM_REGION		7
628 
629 #define MODULE_ALIAS_CXL(type) MODULE_ALIAS("cxl:t" __stringify(type) "*")
630 #define CXL_MODALIAS_FMT "cxl:t%d"
631 
632 struct cxl_nvdimm_bridge *to_cxl_nvdimm_bridge(struct device *dev);
633 struct cxl_nvdimm_bridge *devm_cxl_add_nvdimm_bridge(struct device *host,
634 						     struct cxl_port *port);
635 struct cxl_nvdimm *to_cxl_nvdimm(struct device *dev);
636 bool is_cxl_nvdimm(struct device *dev);
637 bool is_cxl_nvdimm_bridge(struct device *dev);
638 int devm_cxl_add_nvdimm(struct device *host, struct cxl_memdev *cxlmd);
639 struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct device *dev);
640 
641 #ifdef CONFIG_CXL_REGION
642 bool is_cxl_pmem_region(struct device *dev);
643 struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev);
644 #else
645 static inline bool is_cxl_pmem_region(struct device *dev)
646 {
647 	return false;
648 }
649 static inline struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev)
650 {
651 	return NULL;
652 }
653 #endif
654 
655 /*
656  * Unit test builds overrides this to __weak, find the 'strong' version
657  * of these symbols in tools/testing/cxl/.
658  */
659 #ifndef __mock
660 #define __mock static
661 #endif
662 
663 #endif /* __CXL_H__ */
664