xref: /openbmc/linux/drivers/cxl/cxl.h (revision 1ad3f701c3999904d0c6cdea299df16c6cd9878d)
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_RAS 0x2
37 #define   CXL_CM_CAP_CAP_ID_HDM 0x5
38 #define   CXL_CM_CAP_CAP_HDM_VERSION 1
39 
40 /* HDM decoders CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure */
41 #define CXL_HDM_DECODER_CAP_OFFSET 0x0
42 #define   CXL_HDM_DECODER_COUNT_MASK GENMASK(3, 0)
43 #define   CXL_HDM_DECODER_TARGET_COUNT_MASK GENMASK(7, 4)
44 #define   CXL_HDM_DECODER_INTERLEAVE_11_8 BIT(8)
45 #define   CXL_HDM_DECODER_INTERLEAVE_14_12 BIT(9)
46 #define CXL_HDM_DECODER_CTRL_OFFSET 0x4
47 #define   CXL_HDM_DECODER_ENABLE BIT(1)
48 #define CXL_HDM_DECODER0_BASE_LOW_OFFSET(i) (0x20 * (i) + 0x10)
49 #define CXL_HDM_DECODER0_BASE_HIGH_OFFSET(i) (0x20 * (i) + 0x14)
50 #define CXL_HDM_DECODER0_SIZE_LOW_OFFSET(i) (0x20 * (i) + 0x18)
51 #define CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(i) (0x20 * (i) + 0x1c)
52 #define CXL_HDM_DECODER0_CTRL_OFFSET(i) (0x20 * (i) + 0x20)
53 #define   CXL_HDM_DECODER0_CTRL_IG_MASK GENMASK(3, 0)
54 #define   CXL_HDM_DECODER0_CTRL_IW_MASK GENMASK(7, 4)
55 #define   CXL_HDM_DECODER0_CTRL_LOCK BIT(8)
56 #define   CXL_HDM_DECODER0_CTRL_COMMIT BIT(9)
57 #define   CXL_HDM_DECODER0_CTRL_COMMITTED BIT(10)
58 #define   CXL_HDM_DECODER0_CTRL_COMMIT_ERROR BIT(11)
59 #define   CXL_HDM_DECODER0_CTRL_TYPE BIT(12)
60 #define CXL_HDM_DECODER0_TL_LOW(i) (0x20 * (i) + 0x24)
61 #define CXL_HDM_DECODER0_TL_HIGH(i) (0x20 * (i) + 0x28)
62 #define CXL_HDM_DECODER0_SKIP_LOW(i) CXL_HDM_DECODER0_TL_LOW(i)
63 #define CXL_HDM_DECODER0_SKIP_HIGH(i) CXL_HDM_DECODER0_TL_HIGH(i)
64 
65 /* HDM decoder control register constants CXL 3.0 8.2.5.19.7 */
66 #define CXL_DECODER_MIN_GRANULARITY 256
67 #define CXL_DECODER_MAX_ENCODED_IG 6
68 
69 static inline int cxl_hdm_decoder_count(u32 cap_hdr)
70 {
71 	int val = FIELD_GET(CXL_HDM_DECODER_COUNT_MASK, cap_hdr);
72 
73 	return val ? val * 2 : 1;
74 }
75 
76 /* Encode defined in CXL 2.0 8.2.5.12.7 HDM Decoder Control Register */
77 static inline int eig_to_granularity(u16 eig, unsigned int *granularity)
78 {
79 	if (eig > CXL_DECODER_MAX_ENCODED_IG)
80 		return -EINVAL;
81 	*granularity = CXL_DECODER_MIN_GRANULARITY << eig;
82 	return 0;
83 }
84 
85 /* Encode defined in CXL ECN "3, 6, 12 and 16-way memory Interleaving" */
86 static inline int eiw_to_ways(u8 eiw, unsigned int *ways)
87 {
88 	switch (eiw) {
89 	case 0 ... 4:
90 		*ways = 1 << eiw;
91 		break;
92 	case 8 ... 10:
93 		*ways = 3 << (eiw - 8);
94 		break;
95 	default:
96 		return -EINVAL;
97 	}
98 
99 	return 0;
100 }
101 
102 static inline int granularity_to_eig(int granularity, u16 *eig)
103 {
104 	if (granularity > SZ_16K || granularity < CXL_DECODER_MIN_GRANULARITY ||
105 	    !is_power_of_2(granularity))
106 		return -EINVAL;
107 	*eig = ilog2(granularity) - 8;
108 	return 0;
109 }
110 
111 static inline int ways_to_eiw(unsigned int ways, u8 *eiw)
112 {
113 	if (ways > 16)
114 		return -EINVAL;
115 	if (is_power_of_2(ways)) {
116 		*eiw = ilog2(ways);
117 		return 0;
118 	}
119 	if (ways % 3)
120 		return -EINVAL;
121 	ways /= 3;
122 	if (!is_power_of_2(ways))
123 		return -EINVAL;
124 	*eiw = ilog2(ways) + 8;
125 	return 0;
126 }
127 
128 /* RAS Registers CXL 2.0 8.2.5.9 CXL RAS Capability Structure */
129 #define CXL_RAS_UNCORRECTABLE_STATUS_OFFSET 0x0
130 #define   CXL_RAS_UNCORRECTABLE_STATUS_MASK (GENMASK(16, 14) | GENMASK(11, 0))
131 #define CXL_RAS_UNCORRECTABLE_MASK_OFFSET 0x4
132 #define   CXL_RAS_UNCORRECTABLE_MASK_MASK (GENMASK(16, 14) | GENMASK(11, 0))
133 #define   CXL_RAS_UNCORRECTABLE_MASK_F256B_MASK BIT(8)
134 #define CXL_RAS_UNCORRECTABLE_SEVERITY_OFFSET 0x8
135 #define   CXL_RAS_UNCORRECTABLE_SEVERITY_MASK (GENMASK(16, 14) | GENMASK(11, 0))
136 #define CXL_RAS_CORRECTABLE_STATUS_OFFSET 0xC
137 #define   CXL_RAS_CORRECTABLE_STATUS_MASK GENMASK(6, 0)
138 #define CXL_RAS_CORRECTABLE_MASK_OFFSET 0x10
139 #define   CXL_RAS_CORRECTABLE_MASK_MASK GENMASK(6, 0)
140 #define CXL_RAS_CAP_CONTROL_OFFSET 0x14
141 #define CXL_RAS_CAP_CONTROL_FE_MASK GENMASK(5, 0)
142 #define CXL_RAS_HEADER_LOG_OFFSET 0x18
143 #define CXL_RAS_CAPABILITY_LENGTH 0x58
144 #define CXL_HEADERLOG_SIZE SZ_512
145 #define CXL_HEADERLOG_SIZE_U32 SZ_512 / sizeof(u32)
146 
147 /* CXL 2.0 8.2.8.1 Device Capabilities Array Register */
148 #define CXLDEV_CAP_ARRAY_OFFSET 0x0
149 #define   CXLDEV_CAP_ARRAY_CAP_ID 0
150 #define   CXLDEV_CAP_ARRAY_ID_MASK GENMASK_ULL(15, 0)
151 #define   CXLDEV_CAP_ARRAY_COUNT_MASK GENMASK_ULL(47, 32)
152 /* CXL 2.0 8.2.8.2 CXL Device Capability Header Register */
153 #define CXLDEV_CAP_HDR_CAP_ID_MASK GENMASK(15, 0)
154 /* CXL 2.0 8.2.8.2.1 CXL Device Capabilities */
155 #define CXLDEV_CAP_CAP_ID_DEVICE_STATUS 0x1
156 #define CXLDEV_CAP_CAP_ID_PRIMARY_MAILBOX 0x2
157 #define CXLDEV_CAP_CAP_ID_SECONDARY_MAILBOX 0x3
158 #define CXLDEV_CAP_CAP_ID_MEMDEV 0x4000
159 
160 /* CXL 3.0 8.2.8.3.1 Event Status Register */
161 #define CXLDEV_DEV_EVENT_STATUS_OFFSET		0x00
162 #define CXLDEV_EVENT_STATUS_INFO		BIT(0)
163 #define CXLDEV_EVENT_STATUS_WARN		BIT(1)
164 #define CXLDEV_EVENT_STATUS_FAIL		BIT(2)
165 #define CXLDEV_EVENT_STATUS_FATAL		BIT(3)
166 
167 #define CXLDEV_EVENT_STATUS_ALL (CXLDEV_EVENT_STATUS_INFO |	\
168 				 CXLDEV_EVENT_STATUS_WARN |	\
169 				 CXLDEV_EVENT_STATUS_FAIL |	\
170 				 CXLDEV_EVENT_STATUS_FATAL)
171 
172 /* CXL rev 3.0 section 8.2.9.2.4; Table 8-52 */
173 #define CXLDEV_EVENT_INT_MODE_MASK	GENMASK(1, 0)
174 #define CXLDEV_EVENT_INT_MSGNUM_MASK	GENMASK(7, 4)
175 
176 /* CXL 2.0 8.2.8.4 Mailbox Registers */
177 #define CXLDEV_MBOX_CAPS_OFFSET 0x00
178 #define   CXLDEV_MBOX_CAP_PAYLOAD_SIZE_MASK GENMASK(4, 0)
179 #define CXLDEV_MBOX_CTRL_OFFSET 0x04
180 #define   CXLDEV_MBOX_CTRL_DOORBELL BIT(0)
181 #define CXLDEV_MBOX_CMD_OFFSET 0x08
182 #define   CXLDEV_MBOX_CMD_COMMAND_OPCODE_MASK GENMASK_ULL(15, 0)
183 #define   CXLDEV_MBOX_CMD_PAYLOAD_LENGTH_MASK GENMASK_ULL(36, 16)
184 #define CXLDEV_MBOX_STATUS_OFFSET 0x10
185 #define   CXLDEV_MBOX_STATUS_RET_CODE_MASK GENMASK_ULL(47, 32)
186 #define CXLDEV_MBOX_BG_CMD_STATUS_OFFSET 0x18
187 #define CXLDEV_MBOX_PAYLOAD_OFFSET 0x20
188 
189 /*
190  * Using struct_group() allows for per register-block-type helper routines,
191  * without requiring block-type agnostic code to include the prefix.
192  */
193 struct cxl_regs {
194 	/*
195 	 * Common set of CXL Component register block base pointers
196 	 * @hdm_decoder: CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure
197 	 * @ras: CXL 2.0 8.2.5.9 CXL RAS Capability Structure
198 	 */
199 	struct_group_tagged(cxl_component_regs, component,
200 		void __iomem *hdm_decoder;
201 		void __iomem *ras;
202 	);
203 	/*
204 	 * Common set of CXL Device register block base pointers
205 	 * @status: CXL 2.0 8.2.8.3 Device Status Registers
206 	 * @mbox: CXL 2.0 8.2.8.4 Mailbox Registers
207 	 * @memdev: CXL 2.0 8.2.8.5 Memory Device Registers
208 	 */
209 	struct_group_tagged(cxl_device_regs, device_regs,
210 		void __iomem *status, *mbox, *memdev;
211 	);
212 
213 	struct_group_tagged(cxl_pmu_regs, pmu_regs,
214 		void __iomem *pmu;
215 	);
216 };
217 
218 struct cxl_reg_map {
219 	bool valid;
220 	int id;
221 	unsigned long offset;
222 	unsigned long size;
223 };
224 
225 struct cxl_component_reg_map {
226 	struct cxl_reg_map hdm_decoder;
227 	struct cxl_reg_map ras;
228 };
229 
230 struct cxl_device_reg_map {
231 	struct cxl_reg_map status;
232 	struct cxl_reg_map mbox;
233 	struct cxl_reg_map memdev;
234 };
235 
236 struct cxl_pmu_reg_map {
237 	struct cxl_reg_map pmu;
238 };
239 
240 /**
241  * struct cxl_register_map - DVSEC harvested register block mapping parameters
242  * @base: virtual base of the register-block-BAR + @block_offset
243  * @resource: physical resource base of the register block
244  * @max_size: maximum mapping size to perform register search
245  * @reg_type: see enum cxl_regloc_type
246  * @component_map: cxl_reg_map for component registers
247  * @device_map: cxl_reg_maps for device registers
248  * @pmu_map: cxl_reg_maps for CXL Performance Monitoring Units
249  */
250 struct cxl_register_map {
251 	void __iomem *base;
252 	resource_size_t resource;
253 	resource_size_t max_size;
254 	u8 reg_type;
255 	union {
256 		struct cxl_component_reg_map component_map;
257 		struct cxl_device_reg_map device_map;
258 		struct cxl_pmu_reg_map pmu_map;
259 	};
260 };
261 
262 void cxl_probe_component_regs(struct device *dev, void __iomem *base,
263 			      struct cxl_component_reg_map *map);
264 void cxl_probe_device_regs(struct device *dev, void __iomem *base,
265 			   struct cxl_device_reg_map *map);
266 int cxl_map_component_regs(struct device *dev, struct cxl_component_regs *regs,
267 			   struct cxl_register_map *map,
268 			   unsigned long map_mask);
269 int cxl_map_device_regs(struct device *dev, struct cxl_device_regs *regs,
270 			struct cxl_register_map *map);
271 int cxl_map_pmu_regs(struct pci_dev *pdev, struct cxl_pmu_regs *regs,
272 		     struct cxl_register_map *map);
273 
274 enum cxl_regloc_type;
275 int cxl_count_regblock(struct pci_dev *pdev, enum cxl_regloc_type type);
276 int cxl_find_regblock_instance(struct pci_dev *pdev, enum cxl_regloc_type type,
277 			       struct cxl_register_map *map, int index);
278 int cxl_find_regblock(struct pci_dev *pdev, enum cxl_regloc_type type,
279 		      struct cxl_register_map *map);
280 
281 enum cxl_rcrb {
282 	CXL_RCRB_DOWNSTREAM,
283 	CXL_RCRB_UPSTREAM,
284 };
285 resource_size_t cxl_rcrb_to_component(struct device *dev,
286 				      resource_size_t rcrb,
287 				      enum cxl_rcrb which);
288 
289 #define CXL_RESOURCE_NONE ((resource_size_t) -1)
290 #define CXL_TARGET_STRLEN 20
291 
292 /*
293  * cxl_decoder flags that define the type of memory / devices this
294  * decoder supports as well as configuration lock status See "CXL 2.0
295  * 8.2.5.12.7 CXL HDM Decoder 0 Control Register" for details.
296  * Additionally indicate whether decoder settings were autodetected,
297  * user customized.
298  */
299 #define CXL_DECODER_F_RAM   BIT(0)
300 #define CXL_DECODER_F_PMEM  BIT(1)
301 #define CXL_DECODER_F_TYPE2 BIT(2)
302 #define CXL_DECODER_F_TYPE3 BIT(3)
303 #define CXL_DECODER_F_LOCK  BIT(4)
304 #define CXL_DECODER_F_ENABLE    BIT(5)
305 #define CXL_DECODER_F_MASK  GENMASK(5, 0)
306 
307 enum cxl_decoder_type {
308        CXL_DECODER_ACCELERATOR = 2,
309        CXL_DECODER_EXPANDER = 3,
310 };
311 
312 /*
313  * Current specification goes up to 8, double that seems a reasonable
314  * software max for the foreseeable future
315  */
316 #define CXL_DECODER_MAX_INTERLEAVE 16
317 
318 
319 /**
320  * struct cxl_decoder - Common CXL HDM Decoder Attributes
321  * @dev: this decoder's device
322  * @id: kernel device name id
323  * @hpa_range: Host physical address range mapped by this decoder
324  * @interleave_ways: number of cxl_dports in this decode
325  * @interleave_granularity: data stride per dport
326  * @target_type: accelerator vs expander (type2 vs type3) selector
327  * @region: currently assigned region for this decoder
328  * @flags: memory type capabilities and locking
329  * @commit: device/decoder-type specific callback to commit settings to hw
330  * @reset: device/decoder-type specific callback to reset hw settings
331 */
332 struct cxl_decoder {
333 	struct device dev;
334 	int id;
335 	struct range hpa_range;
336 	int interleave_ways;
337 	int interleave_granularity;
338 	enum cxl_decoder_type target_type;
339 	struct cxl_region *region;
340 	unsigned long flags;
341 	int (*commit)(struct cxl_decoder *cxld);
342 	int (*reset)(struct cxl_decoder *cxld);
343 };
344 
345 /*
346  * CXL_DECODER_DEAD prevents endpoints from being reattached to regions
347  * while cxld_unregister() is running
348  */
349 enum cxl_decoder_mode {
350 	CXL_DECODER_NONE,
351 	CXL_DECODER_RAM,
352 	CXL_DECODER_PMEM,
353 	CXL_DECODER_MIXED,
354 	CXL_DECODER_DEAD,
355 };
356 
357 static inline const char *cxl_decoder_mode_name(enum cxl_decoder_mode mode)
358 {
359 	static const char * const names[] = {
360 		[CXL_DECODER_NONE] = "none",
361 		[CXL_DECODER_RAM] = "ram",
362 		[CXL_DECODER_PMEM] = "pmem",
363 		[CXL_DECODER_MIXED] = "mixed",
364 	};
365 
366 	if (mode >= CXL_DECODER_NONE && mode <= CXL_DECODER_MIXED)
367 		return names[mode];
368 	return "mixed";
369 }
370 
371 /*
372  * Track whether this decoder is reserved for region autodiscovery, or
373  * free for userspace provisioning.
374  */
375 enum cxl_decoder_state {
376 	CXL_DECODER_STATE_MANUAL,
377 	CXL_DECODER_STATE_AUTO,
378 };
379 
380 /**
381  * struct cxl_endpoint_decoder - Endpoint  / SPA to DPA decoder
382  * @cxld: base cxl_decoder_object
383  * @dpa_res: actively claimed DPA span of this decoder
384  * @skip: offset into @dpa_res where @cxld.hpa_range maps
385  * @mode: which memory type / access-mode-partition this decoder targets
386  * @state: autodiscovery state
387  * @pos: interleave position in @cxld.region
388  */
389 struct cxl_endpoint_decoder {
390 	struct cxl_decoder cxld;
391 	struct resource *dpa_res;
392 	resource_size_t skip;
393 	enum cxl_decoder_mode mode;
394 	enum cxl_decoder_state state;
395 	int pos;
396 };
397 
398 /**
399  * struct cxl_switch_decoder - Switch specific CXL HDM Decoder
400  * @cxld: base cxl_decoder object
401  * @target_lock: coordinate coherent reads of the target list
402  * @nr_targets: number of elements in @target
403  * @target: active ordered target list in current decoder configuration
404  *
405  * The 'switch' decoder type represents the decoder instances of cxl_port's that
406  * route from the root of a CXL memory decode topology to the endpoints. They
407  * come in two flavors, root-level decoders, statically defined by platform
408  * firmware, and mid-level decoders, where interleave-granularity,
409  * interleave-width, and the target list are mutable.
410  */
411 struct cxl_switch_decoder {
412 	struct cxl_decoder cxld;
413 	seqlock_t target_lock;
414 	int nr_targets;
415 	struct cxl_dport *target[];
416 };
417 
418 struct cxl_root_decoder;
419 typedef struct cxl_dport *(*cxl_calc_hb_fn)(struct cxl_root_decoder *cxlrd,
420 					    int pos);
421 
422 /**
423  * struct cxl_root_decoder - Static platform CXL address decoder
424  * @res: host / parent resource for region allocations
425  * @region_id: region id for next region provisioning event
426  * @calc_hb: which host bridge covers the n'th position by granularity
427  * @platform_data: platform specific configuration data
428  * @range_lock: sync region autodiscovery by address range
429  * @cxlsd: base cxl switch decoder
430  */
431 struct cxl_root_decoder {
432 	struct resource *res;
433 	atomic_t region_id;
434 	cxl_calc_hb_fn calc_hb;
435 	void *platform_data;
436 	struct mutex range_lock;
437 	struct cxl_switch_decoder cxlsd;
438 };
439 
440 /*
441  * enum cxl_config_state - State machine for region configuration
442  * @CXL_CONFIG_IDLE: Any sysfs attribute can be written freely
443  * @CXL_CONFIG_INTERLEAVE_ACTIVE: region size has been set, no more
444  * changes to interleave_ways or interleave_granularity
445  * @CXL_CONFIG_ACTIVE: All targets have been added the region is now
446  * active
447  * @CXL_CONFIG_RESET_PENDING: see commit_store()
448  * @CXL_CONFIG_COMMIT: Soft-config has been committed to hardware
449  */
450 enum cxl_config_state {
451 	CXL_CONFIG_IDLE,
452 	CXL_CONFIG_INTERLEAVE_ACTIVE,
453 	CXL_CONFIG_ACTIVE,
454 	CXL_CONFIG_RESET_PENDING,
455 	CXL_CONFIG_COMMIT,
456 };
457 
458 /**
459  * struct cxl_region_params - region settings
460  * @state: allow the driver to lockdown further parameter changes
461  * @uuid: unique id for persistent regions
462  * @interleave_ways: number of endpoints in the region
463  * @interleave_granularity: capacity each endpoint contributes to a stripe
464  * @res: allocated iomem capacity for this region
465  * @targets: active ordered targets in current decoder configuration
466  * @nr_targets: number of targets
467  *
468  * State transitions are protected by the cxl_region_rwsem
469  */
470 struct cxl_region_params {
471 	enum cxl_config_state state;
472 	uuid_t uuid;
473 	int interleave_ways;
474 	int interleave_granularity;
475 	struct resource *res;
476 	struct cxl_endpoint_decoder *targets[CXL_DECODER_MAX_INTERLEAVE];
477 	int nr_targets;
478 };
479 
480 /*
481  * Flag whether this region needs to have its HPA span synchronized with
482  * CPU cache state at region activation time.
483  */
484 #define CXL_REGION_F_INCOHERENT 0
485 
486 /*
487  * Indicate whether this region has been assembled by autodetection or
488  * userspace assembly. Prevent endpoint decoders outside of automatic
489  * detection from being added to the region.
490  */
491 #define CXL_REGION_F_AUTO 1
492 
493 /**
494  * struct cxl_region - CXL region
495  * @dev: This region's device
496  * @id: This region's id. Id is globally unique across all regions
497  * @mode: Endpoint decoder allocation / access mode
498  * @type: Endpoint decoder target type
499  * @cxl_nvb: nvdimm bridge for coordinating @cxlr_pmem setup / shutdown
500  * @cxlr_pmem: (for pmem regions) cached copy of the nvdimm bridge
501  * @flags: Region state flags
502  * @params: active + config params for the region
503  */
504 struct cxl_region {
505 	struct device dev;
506 	int id;
507 	enum cxl_decoder_mode mode;
508 	enum cxl_decoder_type type;
509 	struct cxl_nvdimm_bridge *cxl_nvb;
510 	struct cxl_pmem_region *cxlr_pmem;
511 	unsigned long flags;
512 	struct cxl_region_params params;
513 };
514 
515 struct cxl_nvdimm_bridge {
516 	int id;
517 	struct device dev;
518 	struct cxl_port *port;
519 	struct nvdimm_bus *nvdimm_bus;
520 	struct nvdimm_bus_descriptor nd_desc;
521 };
522 
523 #define CXL_DEV_ID_LEN 19
524 
525 struct cxl_nvdimm {
526 	struct device dev;
527 	struct cxl_memdev *cxlmd;
528 	u8 dev_id[CXL_DEV_ID_LEN]; /* for nvdimm, string of 'serial' */
529 };
530 
531 struct cxl_pmem_region_mapping {
532 	struct cxl_memdev *cxlmd;
533 	struct cxl_nvdimm *cxl_nvd;
534 	u64 start;
535 	u64 size;
536 	int position;
537 };
538 
539 struct cxl_pmem_region {
540 	struct device dev;
541 	struct cxl_region *cxlr;
542 	struct nd_region *nd_region;
543 	struct range hpa_range;
544 	int nr_mappings;
545 	struct cxl_pmem_region_mapping mapping[];
546 };
547 
548 struct cxl_dax_region {
549 	struct device dev;
550 	struct cxl_region *cxlr;
551 	struct range hpa_range;
552 };
553 
554 /**
555  * struct cxl_port - logical collection of upstream port devices and
556  *		     downstream port devices to construct a CXL memory
557  *		     decode hierarchy.
558  * @dev: this port's device
559  * @uport: PCI or platform device implementing the upstream port capability
560  * @host_bridge: Shortcut to the platform attach point for this port
561  * @id: id for port device-name
562  * @dports: cxl_dport instances referenced by decoders
563  * @endpoints: cxl_ep instances, endpoints that are a descendant of this port
564  * @regions: cxl_region_ref instances, regions mapped by this port
565  * @parent_dport: dport that points to this port in the parent
566  * @decoder_ida: allocator for decoder ids
567  * @nr_dports: number of entries in @dports
568  * @hdm_end: track last allocated HDM decoder instance for allocation ordering
569  * @commit_end: cursor to track highest committed decoder for commit ordering
570  * @component_reg_phys: component register capability base address (optional)
571  * @dead: last ep has been removed, force port re-creation
572  * @depth: How deep this port is relative to the root. depth 0 is the root.
573  * @cdat: Cached CDAT data
574  * @cdat_available: Should a CDAT attribute be available in sysfs
575  */
576 struct cxl_port {
577 	struct device dev;
578 	struct device *uport;
579 	struct device *host_bridge;
580 	int id;
581 	struct xarray dports;
582 	struct xarray endpoints;
583 	struct xarray regions;
584 	struct cxl_dport *parent_dport;
585 	struct ida decoder_ida;
586 	int nr_dports;
587 	int hdm_end;
588 	int commit_end;
589 	resource_size_t component_reg_phys;
590 	bool dead;
591 	unsigned int depth;
592 	struct cxl_cdat {
593 		void *table;
594 		size_t length;
595 	} cdat;
596 	bool cdat_available;
597 };
598 
599 static inline struct cxl_dport *
600 cxl_find_dport_by_dev(struct cxl_port *port, const struct device *dport_dev)
601 {
602 	return xa_load(&port->dports, (unsigned long)dport_dev);
603 }
604 
605 /**
606  * struct cxl_dport - CXL downstream port
607  * @dport: PCI bridge or firmware device representing the downstream link
608  * @port_id: unique hardware identifier for dport in decoder target list
609  * @component_reg_phys: downstream port component registers
610  * @rcrb: base address for the Root Complex Register Block
611  * @rch: Indicate whether this dport was enumerated in RCH or VH mode
612  * @port: reference to cxl_port that contains this downstream port
613  */
614 struct cxl_dport {
615 	struct device *dport;
616 	int port_id;
617 	resource_size_t component_reg_phys;
618 	resource_size_t rcrb;
619 	bool rch;
620 	struct cxl_port *port;
621 };
622 
623 /**
624  * struct cxl_ep - track an endpoint's interest in a port
625  * @ep: device that hosts a generic CXL endpoint (expander or accelerator)
626  * @dport: which dport routes to this endpoint on @port
627  * @next: cxl switch port across the link attached to @dport NULL if
628  *	  attached to an endpoint
629  */
630 struct cxl_ep {
631 	struct device *ep;
632 	struct cxl_dport *dport;
633 	struct cxl_port *next;
634 };
635 
636 /**
637  * struct cxl_region_ref - track a region's interest in a port
638  * @port: point in topology to install this reference
639  * @decoder: decoder assigned for @region in @port
640  * @region: region for this reference
641  * @endpoints: cxl_ep references for region members beneath @port
642  * @nr_targets_set: track how many targets have been programmed during setup
643  * @nr_eps: number of endpoints beneath @port
644  * @nr_targets: number of distinct targets needed to reach @nr_eps
645  */
646 struct cxl_region_ref {
647 	struct cxl_port *port;
648 	struct cxl_decoder *decoder;
649 	struct cxl_region *region;
650 	struct xarray endpoints;
651 	int nr_targets_set;
652 	int nr_eps;
653 	int nr_targets;
654 };
655 
656 /*
657  * The platform firmware device hosting the root is also the top of the
658  * CXL port topology. All other CXL ports have another CXL port as their
659  * parent and their ->uport / host device is out-of-line of the port
660  * ancestry.
661  */
662 static inline bool is_cxl_root(struct cxl_port *port)
663 {
664 	return port->uport == port->dev.parent;
665 }
666 
667 bool is_cxl_port(const struct device *dev);
668 struct cxl_port *to_cxl_port(const struct device *dev);
669 struct pci_bus;
670 int devm_cxl_register_pci_bus(struct device *host, struct device *uport,
671 			      struct pci_bus *bus);
672 struct pci_bus *cxl_port_to_pci_bus(struct cxl_port *port);
673 struct cxl_port *devm_cxl_add_port(struct device *host, struct device *uport,
674 				   resource_size_t component_reg_phys,
675 				   struct cxl_dport *parent_dport);
676 struct cxl_port *find_cxl_root(struct cxl_port *port);
677 int devm_cxl_enumerate_ports(struct cxl_memdev *cxlmd);
678 void cxl_bus_rescan(void);
679 void cxl_bus_drain(void);
680 struct cxl_port *cxl_mem_find_port(struct cxl_memdev *cxlmd,
681 				   struct cxl_dport **dport);
682 bool schedule_cxl_memdev_detach(struct cxl_memdev *cxlmd);
683 
684 struct cxl_dport *devm_cxl_add_dport(struct cxl_port *port,
685 				     struct device *dport, int port_id,
686 				     resource_size_t component_reg_phys);
687 struct cxl_dport *devm_cxl_add_rch_dport(struct cxl_port *port,
688 					 struct device *dport_dev, int port_id,
689 					 resource_size_t component_reg_phys,
690 					 resource_size_t rcrb);
691 
692 struct cxl_decoder *to_cxl_decoder(struct device *dev);
693 struct cxl_root_decoder *to_cxl_root_decoder(struct device *dev);
694 struct cxl_switch_decoder *to_cxl_switch_decoder(struct device *dev);
695 struct cxl_endpoint_decoder *to_cxl_endpoint_decoder(struct device *dev);
696 bool is_root_decoder(struct device *dev);
697 bool is_switch_decoder(struct device *dev);
698 bool is_endpoint_decoder(struct device *dev);
699 struct cxl_root_decoder *cxl_root_decoder_alloc(struct cxl_port *port,
700 						unsigned int nr_targets,
701 						cxl_calc_hb_fn calc_hb);
702 struct cxl_dport *cxl_hb_modulo(struct cxl_root_decoder *cxlrd, int pos);
703 struct cxl_switch_decoder *cxl_switch_decoder_alloc(struct cxl_port *port,
704 						    unsigned int nr_targets);
705 int cxl_decoder_add(struct cxl_decoder *cxld, int *target_map);
706 struct cxl_endpoint_decoder *cxl_endpoint_decoder_alloc(struct cxl_port *port);
707 int cxl_decoder_add_locked(struct cxl_decoder *cxld, int *target_map);
708 int cxl_decoder_autoremove(struct device *host, struct cxl_decoder *cxld);
709 int cxl_endpoint_autoremove(struct cxl_memdev *cxlmd, struct cxl_port *endpoint);
710 
711 /**
712  * struct cxl_endpoint_dvsec_info - Cached DVSEC info
713  * @mem_enabled: cached value of mem_enabled in the DVSEC at init time
714  * @ranges: Number of active HDM ranges this device uses.
715  * @port: endpoint port associated with this info instance
716  * @dvsec_range: cached attributes of the ranges in the DVSEC, PCIE_DEVICE
717  */
718 struct cxl_endpoint_dvsec_info {
719 	bool mem_enabled;
720 	int ranges;
721 	struct cxl_port *port;
722 	struct range dvsec_range[2];
723 };
724 
725 struct cxl_hdm;
726 struct cxl_hdm *devm_cxl_setup_hdm(struct cxl_port *port,
727 				   struct cxl_endpoint_dvsec_info *info);
728 int devm_cxl_enable_hdm(struct cxl_port *port, struct cxl_hdm *cxlhdm);
729 int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm,
730 				struct cxl_endpoint_dvsec_info *info);
731 int devm_cxl_add_passthrough_decoder(struct cxl_port *port);
732 int cxl_dvsec_rr_decode(struct device *dev, int dvsec,
733 			struct cxl_endpoint_dvsec_info *info);
734 
735 bool is_cxl_region(struct device *dev);
736 
737 extern struct bus_type cxl_bus_type;
738 
739 struct cxl_driver {
740 	const char *name;
741 	int (*probe)(struct device *dev);
742 	void (*remove)(struct device *dev);
743 	struct device_driver drv;
744 	int id;
745 };
746 
747 static inline struct cxl_driver *to_cxl_drv(struct device_driver *drv)
748 {
749 	return container_of(drv, struct cxl_driver, drv);
750 }
751 
752 int __cxl_driver_register(struct cxl_driver *cxl_drv, struct module *owner,
753 			  const char *modname);
754 #define cxl_driver_register(x) __cxl_driver_register(x, THIS_MODULE, KBUILD_MODNAME)
755 void cxl_driver_unregister(struct cxl_driver *cxl_drv);
756 
757 #define module_cxl_driver(__cxl_driver) \
758 	module_driver(__cxl_driver, cxl_driver_register, cxl_driver_unregister)
759 
760 #define CXL_DEVICE_NVDIMM_BRIDGE	1
761 #define CXL_DEVICE_NVDIMM		2
762 #define CXL_DEVICE_PORT			3
763 #define CXL_DEVICE_ROOT			4
764 #define CXL_DEVICE_MEMORY_EXPANDER	5
765 #define CXL_DEVICE_REGION		6
766 #define CXL_DEVICE_PMEM_REGION		7
767 #define CXL_DEVICE_DAX_REGION		8
768 #define CXL_DEVICE_PMU			9
769 
770 #define MODULE_ALIAS_CXL(type) MODULE_ALIAS("cxl:t" __stringify(type) "*")
771 #define CXL_MODALIAS_FMT "cxl:t%d"
772 
773 struct cxl_nvdimm_bridge *to_cxl_nvdimm_bridge(struct device *dev);
774 struct cxl_nvdimm_bridge *devm_cxl_add_nvdimm_bridge(struct device *host,
775 						     struct cxl_port *port);
776 struct cxl_nvdimm *to_cxl_nvdimm(struct device *dev);
777 bool is_cxl_nvdimm(struct device *dev);
778 bool is_cxl_nvdimm_bridge(struct device *dev);
779 int devm_cxl_add_nvdimm(struct cxl_memdev *cxlmd);
780 struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_memdev *cxlmd);
781 
782 #ifdef CONFIG_CXL_REGION
783 bool is_cxl_pmem_region(struct device *dev);
784 struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev);
785 int cxl_add_to_region(struct cxl_port *root,
786 		      struct cxl_endpoint_decoder *cxled);
787 struct cxl_dax_region *to_cxl_dax_region(struct device *dev);
788 #else
789 static inline bool is_cxl_pmem_region(struct device *dev)
790 {
791 	return false;
792 }
793 static inline struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev)
794 {
795 	return NULL;
796 }
797 static inline int cxl_add_to_region(struct cxl_port *root,
798 				    struct cxl_endpoint_decoder *cxled)
799 {
800 	return 0;
801 }
802 static inline struct cxl_dax_region *to_cxl_dax_region(struct device *dev)
803 {
804 	return NULL;
805 }
806 #endif
807 
808 /*
809  * Unit test builds overrides this to __weak, find the 'strong' version
810  * of these symbols in tools/testing/cxl/.
811  */
812 #ifndef __mock
813 #define __mock static
814 #endif
815 
816 #endif /* __CXL_H__ */
817