xref: /linux/drivers/cxl/cxl.h (revision 5c1672705a1a2389f5ad78e0fea6f08ed32d6f18)
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/notifier.h>
10 #include <linux/bitops.h>
11 #include <linux/log2.h>
12 #include <linux/node.h>
13 #include <linux/io.h>
14 
15 /**
16  * DOC: cxl objects
17  *
18  * The CXL core objects like ports, decoders, and regions are shared
19  * between the subsystem drivers cxl_acpi, cxl_pci, and core drivers
20  * (port-driver, region-driver, nvdimm object-drivers... etc).
21  */
22 
23 /* CXL 2.0 8.2.4 CXL Component Register Layout and Definition */
24 #define CXL_COMPONENT_REG_BLOCK_SIZE SZ_64K
25 
26 /* CXL 2.0 8.2.5 CXL.cache and CXL.mem Registers*/
27 #define CXL_CM_OFFSET 0x1000
28 #define CXL_CM_CAP_HDR_OFFSET 0x0
29 #define   CXL_CM_CAP_HDR_ID_MASK GENMASK(15, 0)
30 #define     CM_CAP_HDR_CAP_ID 1
31 #define   CXL_CM_CAP_HDR_VERSION_MASK GENMASK(19, 16)
32 #define     CM_CAP_HDR_CAP_VERSION 1
33 #define   CXL_CM_CAP_HDR_CACHE_MEM_VERSION_MASK GENMASK(23, 20)
34 #define     CM_CAP_HDR_CACHE_MEM_VERSION 1
35 #define   CXL_CM_CAP_HDR_ARRAY_SIZE_MASK GENMASK(31, 24)
36 #define CXL_CM_CAP_PTR_MASK GENMASK(31, 20)
37 
38 #define   CXL_CM_CAP_CAP_ID_RAS 0x2
39 #define   CXL_CM_CAP_CAP_ID_HDM 0x5
40 #define   CXL_CM_CAP_CAP_HDM_VERSION 1
41 
42 /* HDM decoders CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure */
43 #define CXL_HDM_DECODER_CAP_OFFSET 0x0
44 #define   CXL_HDM_DECODER_COUNT_MASK GENMASK(3, 0)
45 #define   CXL_HDM_DECODER_TARGET_COUNT_MASK GENMASK(7, 4)
46 #define   CXL_HDM_DECODER_INTERLEAVE_11_8 BIT(8)
47 #define   CXL_HDM_DECODER_INTERLEAVE_14_12 BIT(9)
48 #define CXL_HDM_DECODER_CTRL_OFFSET 0x4
49 #define   CXL_HDM_DECODER_ENABLE BIT(1)
50 #define CXL_HDM_DECODER0_BASE_LOW_OFFSET(i) (0x20 * (i) + 0x10)
51 #define CXL_HDM_DECODER0_BASE_HIGH_OFFSET(i) (0x20 * (i) + 0x14)
52 #define CXL_HDM_DECODER0_SIZE_LOW_OFFSET(i) (0x20 * (i) + 0x18)
53 #define CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(i) (0x20 * (i) + 0x1c)
54 #define CXL_HDM_DECODER0_CTRL_OFFSET(i) (0x20 * (i) + 0x20)
55 #define   CXL_HDM_DECODER0_CTRL_IG_MASK GENMASK(3, 0)
56 #define   CXL_HDM_DECODER0_CTRL_IW_MASK GENMASK(7, 4)
57 #define   CXL_HDM_DECODER0_CTRL_LOCK BIT(8)
58 #define   CXL_HDM_DECODER0_CTRL_COMMIT BIT(9)
59 #define   CXL_HDM_DECODER0_CTRL_COMMITTED BIT(10)
60 #define   CXL_HDM_DECODER0_CTRL_COMMIT_ERROR BIT(11)
61 #define   CXL_HDM_DECODER0_CTRL_HOSTONLY BIT(12)
62 #define CXL_HDM_DECODER0_TL_LOW(i) (0x20 * (i) + 0x24)
63 #define CXL_HDM_DECODER0_TL_HIGH(i) (0x20 * (i) + 0x28)
64 #define CXL_HDM_DECODER0_SKIP_LOW(i) CXL_HDM_DECODER0_TL_LOW(i)
65 #define CXL_HDM_DECODER0_SKIP_HIGH(i) CXL_HDM_DECODER0_TL_HIGH(i)
66 
67 /* HDM decoder control register constants CXL 3.0 8.2.5.19.7 */
68 #define CXL_DECODER_MIN_GRANULARITY 256
69 #define CXL_DECODER_MAX_ENCODED_IG 6
70 
71 static inline int cxl_hdm_decoder_count(u32 cap_hdr)
72 {
73 	int val = FIELD_GET(CXL_HDM_DECODER_COUNT_MASK, cap_hdr);
74 
75 	return val ? val * 2 : 1;
76 }
77 
78 /* Encode defined in CXL 2.0 8.2.5.12.7 HDM Decoder Control Register */
79 static inline int eig_to_granularity(u16 eig, unsigned int *granularity)
80 {
81 	if (eig > CXL_DECODER_MAX_ENCODED_IG)
82 		return -EINVAL;
83 	*granularity = CXL_DECODER_MIN_GRANULARITY << eig;
84 	return 0;
85 }
86 
87 /* Encode defined in CXL ECN "3, 6, 12 and 16-way memory Interleaving" */
88 static inline int eiw_to_ways(u8 eiw, unsigned int *ways)
89 {
90 	switch (eiw) {
91 	case 0 ... 4:
92 		*ways = 1 << eiw;
93 		break;
94 	case 8 ... 10:
95 		*ways = 3 << (eiw - 8);
96 		break;
97 	default:
98 		return -EINVAL;
99 	}
100 
101 	return 0;
102 }
103 
104 static inline int granularity_to_eig(int granularity, u16 *eig)
105 {
106 	if (granularity > SZ_16K || granularity < CXL_DECODER_MIN_GRANULARITY ||
107 	    !is_power_of_2(granularity))
108 		return -EINVAL;
109 	*eig = ilog2(granularity) - 8;
110 	return 0;
111 }
112 
113 static inline int ways_to_eiw(unsigned int ways, u8 *eiw)
114 {
115 	if (ways > 16)
116 		return -EINVAL;
117 	if (is_power_of_2(ways)) {
118 		*eiw = ilog2(ways);
119 		return 0;
120 	}
121 	if (ways % 3)
122 		return -EINVAL;
123 	ways /= 3;
124 	if (!is_power_of_2(ways))
125 		return -EINVAL;
126 	*eiw = ilog2(ways) + 8;
127 	return 0;
128 }
129 
130 /* RAS Registers CXL 2.0 8.2.5.9 CXL RAS Capability Structure */
131 #define CXL_RAS_UNCORRECTABLE_STATUS_OFFSET 0x0
132 #define   CXL_RAS_UNCORRECTABLE_STATUS_MASK (GENMASK(16, 14) | GENMASK(11, 0))
133 #define CXL_RAS_UNCORRECTABLE_MASK_OFFSET 0x4
134 #define   CXL_RAS_UNCORRECTABLE_MASK_MASK (GENMASK(16, 14) | GENMASK(11, 0))
135 #define   CXL_RAS_UNCORRECTABLE_MASK_F256B_MASK BIT(8)
136 #define CXL_RAS_UNCORRECTABLE_SEVERITY_OFFSET 0x8
137 #define   CXL_RAS_UNCORRECTABLE_SEVERITY_MASK (GENMASK(16, 14) | GENMASK(11, 0))
138 #define CXL_RAS_CORRECTABLE_STATUS_OFFSET 0xC
139 #define   CXL_RAS_CORRECTABLE_STATUS_MASK GENMASK(6, 0)
140 #define CXL_RAS_CORRECTABLE_MASK_OFFSET 0x10
141 #define   CXL_RAS_CORRECTABLE_MASK_MASK GENMASK(6, 0)
142 #define CXL_RAS_CAP_CONTROL_OFFSET 0x14
143 #define CXL_RAS_CAP_CONTROL_FE_MASK GENMASK(5, 0)
144 #define CXL_RAS_HEADER_LOG_OFFSET 0x18
145 #define CXL_RAS_CAPABILITY_LENGTH 0x58
146 #define CXL_HEADERLOG_SIZE SZ_512
147 #define CXL_HEADERLOG_SIZE_U32 SZ_512 / sizeof(u32)
148 
149 /* CXL 2.0 8.2.8.1 Device Capabilities Array Register */
150 #define CXLDEV_CAP_ARRAY_OFFSET 0x0
151 #define   CXLDEV_CAP_ARRAY_CAP_ID 0
152 #define   CXLDEV_CAP_ARRAY_ID_MASK GENMASK_ULL(15, 0)
153 #define   CXLDEV_CAP_ARRAY_COUNT_MASK GENMASK_ULL(47, 32)
154 /* CXL 2.0 8.2.8.2 CXL Device Capability Header Register */
155 #define CXLDEV_CAP_HDR_CAP_ID_MASK GENMASK(15, 0)
156 /* CXL 2.0 8.2.8.2.1 CXL Device Capabilities */
157 #define CXLDEV_CAP_CAP_ID_DEVICE_STATUS 0x1
158 #define CXLDEV_CAP_CAP_ID_PRIMARY_MAILBOX 0x2
159 #define CXLDEV_CAP_CAP_ID_SECONDARY_MAILBOX 0x3
160 #define CXLDEV_CAP_CAP_ID_MEMDEV 0x4000
161 
162 /* CXL 3.0 8.2.8.3.1 Event Status Register */
163 #define CXLDEV_DEV_EVENT_STATUS_OFFSET		0x00
164 #define CXLDEV_EVENT_STATUS_INFO		BIT(0)
165 #define CXLDEV_EVENT_STATUS_WARN		BIT(1)
166 #define CXLDEV_EVENT_STATUS_FAIL		BIT(2)
167 #define CXLDEV_EVENT_STATUS_FATAL		BIT(3)
168 
169 #define CXLDEV_EVENT_STATUS_ALL (CXLDEV_EVENT_STATUS_INFO |	\
170 				 CXLDEV_EVENT_STATUS_WARN |	\
171 				 CXLDEV_EVENT_STATUS_FAIL |	\
172 				 CXLDEV_EVENT_STATUS_FATAL)
173 
174 /* CXL rev 3.0 section 8.2.9.2.4; Table 8-52 */
175 #define CXLDEV_EVENT_INT_MODE_MASK	GENMASK(1, 0)
176 #define CXLDEV_EVENT_INT_MSGNUM_MASK	GENMASK(7, 4)
177 
178 /* CXL 2.0 8.2.8.4 Mailbox Registers */
179 #define CXLDEV_MBOX_CAPS_OFFSET 0x00
180 #define   CXLDEV_MBOX_CAP_PAYLOAD_SIZE_MASK GENMASK(4, 0)
181 #define   CXLDEV_MBOX_CAP_BG_CMD_IRQ BIT(6)
182 #define   CXLDEV_MBOX_CAP_IRQ_MSGNUM_MASK GENMASK(10, 7)
183 #define CXLDEV_MBOX_CTRL_OFFSET 0x04
184 #define   CXLDEV_MBOX_CTRL_DOORBELL BIT(0)
185 #define   CXLDEV_MBOX_CTRL_BG_CMD_IRQ BIT(2)
186 #define CXLDEV_MBOX_CMD_OFFSET 0x08
187 #define   CXLDEV_MBOX_CMD_COMMAND_OPCODE_MASK GENMASK_ULL(15, 0)
188 #define   CXLDEV_MBOX_CMD_PAYLOAD_LENGTH_MASK GENMASK_ULL(36, 16)
189 #define CXLDEV_MBOX_STATUS_OFFSET 0x10
190 #define   CXLDEV_MBOX_STATUS_BG_CMD BIT(0)
191 #define   CXLDEV_MBOX_STATUS_RET_CODE_MASK GENMASK_ULL(47, 32)
192 #define CXLDEV_MBOX_BG_CMD_STATUS_OFFSET 0x18
193 #define   CXLDEV_MBOX_BG_CMD_COMMAND_OPCODE_MASK GENMASK_ULL(15, 0)
194 #define   CXLDEV_MBOX_BG_CMD_COMMAND_PCT_MASK GENMASK_ULL(22, 16)
195 #define   CXLDEV_MBOX_BG_CMD_COMMAND_RC_MASK GENMASK_ULL(47, 32)
196 #define   CXLDEV_MBOX_BG_CMD_COMMAND_VENDOR_MASK GENMASK_ULL(63, 48)
197 #define CXLDEV_MBOX_PAYLOAD_OFFSET 0x20
198 
199 /*
200  * Using struct_group() allows for per register-block-type helper routines,
201  * without requiring block-type agnostic code to include the prefix.
202  */
203 struct cxl_regs {
204 	/*
205 	 * Common set of CXL Component register block base pointers
206 	 * @hdm_decoder: CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure
207 	 * @ras: CXL 2.0 8.2.5.9 CXL RAS Capability Structure
208 	 */
209 	struct_group_tagged(cxl_component_regs, component,
210 		void __iomem *hdm_decoder;
211 		void __iomem *ras;
212 	);
213 	/*
214 	 * Common set of CXL Device register block base pointers
215 	 * @status: CXL 2.0 8.2.8.3 Device Status Registers
216 	 * @mbox: CXL 2.0 8.2.8.4 Mailbox Registers
217 	 * @memdev: CXL 2.0 8.2.8.5 Memory Device Registers
218 	 */
219 	struct_group_tagged(cxl_device_regs, device_regs,
220 		void __iomem *status, *mbox, *memdev;
221 	);
222 
223 	struct_group_tagged(cxl_pmu_regs, pmu_regs,
224 		void __iomem *pmu;
225 	);
226 
227 	/*
228 	 * RCH downstream port specific RAS register
229 	 * @aer: CXL 3.0 8.2.1.1 RCH Downstream Port RCRB
230 	 */
231 	struct_group_tagged(cxl_rch_regs, rch_regs,
232 		void __iomem *dport_aer;
233 	);
234 };
235 
236 struct cxl_reg_map {
237 	bool valid;
238 	int id;
239 	unsigned long offset;
240 	unsigned long size;
241 };
242 
243 struct cxl_component_reg_map {
244 	struct cxl_reg_map hdm_decoder;
245 	struct cxl_reg_map ras;
246 };
247 
248 struct cxl_device_reg_map {
249 	struct cxl_reg_map status;
250 	struct cxl_reg_map mbox;
251 	struct cxl_reg_map memdev;
252 };
253 
254 struct cxl_pmu_reg_map {
255 	struct cxl_reg_map pmu;
256 };
257 
258 /**
259  * struct cxl_register_map - DVSEC harvested register block mapping parameters
260  * @host: device for devm operations and logging
261  * @base: virtual base of the register-block-BAR + @block_offset
262  * @resource: physical resource base of the register block
263  * @max_size: maximum mapping size to perform register search
264  * @reg_type: see enum cxl_regloc_type
265  * @component_map: cxl_reg_map for component registers
266  * @device_map: cxl_reg_maps for device registers
267  * @pmu_map: cxl_reg_maps for CXL Performance Monitoring Units
268  */
269 struct cxl_register_map {
270 	struct device *host;
271 	void __iomem *base;
272 	resource_size_t resource;
273 	resource_size_t max_size;
274 	u8 reg_type;
275 	union {
276 		struct cxl_component_reg_map component_map;
277 		struct cxl_device_reg_map device_map;
278 		struct cxl_pmu_reg_map pmu_map;
279 	};
280 };
281 
282 void cxl_probe_component_regs(struct device *dev, void __iomem *base,
283 			      struct cxl_component_reg_map *map);
284 void cxl_probe_device_regs(struct device *dev, void __iomem *base,
285 			   struct cxl_device_reg_map *map);
286 int cxl_map_component_regs(const struct cxl_register_map *map,
287 			   struct cxl_component_regs *regs,
288 			   unsigned long map_mask);
289 int cxl_map_device_regs(const struct cxl_register_map *map,
290 			struct cxl_device_regs *regs);
291 int cxl_map_pmu_regs(struct cxl_register_map *map, struct cxl_pmu_regs *regs);
292 
293 enum cxl_regloc_type;
294 int cxl_count_regblock(struct pci_dev *pdev, enum cxl_regloc_type type);
295 int cxl_find_regblock_instance(struct pci_dev *pdev, enum cxl_regloc_type type,
296 			       struct cxl_register_map *map, int index);
297 int cxl_find_regblock(struct pci_dev *pdev, enum cxl_regloc_type type,
298 		      struct cxl_register_map *map);
299 int cxl_setup_regs(struct cxl_register_map *map);
300 struct cxl_dport;
301 resource_size_t cxl_rcd_component_reg_phys(struct device *dev,
302 					   struct cxl_dport *dport);
303 
304 #define CXL_RESOURCE_NONE ((resource_size_t) -1)
305 #define CXL_TARGET_STRLEN 20
306 
307 /*
308  * cxl_decoder flags that define the type of memory / devices this
309  * decoder supports as well as configuration lock status See "CXL 2.0
310  * 8.2.5.12.7 CXL HDM Decoder 0 Control Register" for details.
311  * Additionally indicate whether decoder settings were autodetected,
312  * user customized.
313  */
314 #define CXL_DECODER_F_RAM   BIT(0)
315 #define CXL_DECODER_F_PMEM  BIT(1)
316 #define CXL_DECODER_F_TYPE2 BIT(2)
317 #define CXL_DECODER_F_TYPE3 BIT(3)
318 #define CXL_DECODER_F_LOCK  BIT(4)
319 #define CXL_DECODER_F_ENABLE    BIT(5)
320 #define CXL_DECODER_F_MASK  GENMASK(5, 0)
321 
322 enum cxl_decoder_type {
323 	CXL_DECODER_DEVMEM = 2,
324 	CXL_DECODER_HOSTONLYMEM = 3,
325 };
326 
327 /*
328  * Current specification goes up to 8, double that seems a reasonable
329  * software max for the foreseeable future
330  */
331 #define CXL_DECODER_MAX_INTERLEAVE 16
332 
333 #define CXL_QOS_CLASS_INVALID -1
334 
335 /**
336  * struct cxl_decoder - Common CXL HDM Decoder Attributes
337  * @dev: this decoder's device
338  * @id: kernel device name id
339  * @hpa_range: Host physical address range mapped by this decoder
340  * @interleave_ways: number of cxl_dports in this decode
341  * @interleave_granularity: data stride per dport
342  * @target_type: accelerator vs expander (type2 vs type3) selector
343  * @region: currently assigned region for this decoder
344  * @flags: memory type capabilities and locking
345  * @commit: device/decoder-type specific callback to commit settings to hw
346  * @reset: device/decoder-type specific callback to reset hw settings
347 */
348 struct cxl_decoder {
349 	struct device dev;
350 	int id;
351 	struct range hpa_range;
352 	int interleave_ways;
353 	int interleave_granularity;
354 	enum cxl_decoder_type target_type;
355 	struct cxl_region *region;
356 	unsigned long flags;
357 	int (*commit)(struct cxl_decoder *cxld);
358 	int (*reset)(struct cxl_decoder *cxld);
359 };
360 
361 /*
362  * CXL_DECODER_DEAD prevents endpoints from being reattached to regions
363  * while cxld_unregister() is running
364  */
365 enum cxl_decoder_mode {
366 	CXL_DECODER_NONE,
367 	CXL_DECODER_RAM,
368 	CXL_DECODER_PMEM,
369 	CXL_DECODER_MIXED,
370 	CXL_DECODER_DEAD,
371 };
372 
373 static inline const char *cxl_decoder_mode_name(enum cxl_decoder_mode mode)
374 {
375 	static const char * const names[] = {
376 		[CXL_DECODER_NONE] = "none",
377 		[CXL_DECODER_RAM] = "ram",
378 		[CXL_DECODER_PMEM] = "pmem",
379 		[CXL_DECODER_MIXED] = "mixed",
380 	};
381 
382 	if (mode >= CXL_DECODER_NONE && mode <= CXL_DECODER_MIXED)
383 		return names[mode];
384 	return "mixed";
385 }
386 
387 /*
388  * Track whether this decoder is reserved for region autodiscovery, or
389  * free for userspace provisioning.
390  */
391 enum cxl_decoder_state {
392 	CXL_DECODER_STATE_MANUAL,
393 	CXL_DECODER_STATE_AUTO,
394 };
395 
396 /**
397  * struct cxl_endpoint_decoder - Endpoint  / SPA to DPA decoder
398  * @cxld: base cxl_decoder_object
399  * @dpa_res: actively claimed DPA span of this decoder
400  * @skip: offset into @dpa_res where @cxld.hpa_range maps
401  * @mode: which memory type / access-mode-partition this decoder targets
402  * @state: autodiscovery state
403  * @pos: interleave position in @cxld.region
404  */
405 struct cxl_endpoint_decoder {
406 	struct cxl_decoder cxld;
407 	struct resource *dpa_res;
408 	resource_size_t skip;
409 	enum cxl_decoder_mode mode;
410 	enum cxl_decoder_state state;
411 	int pos;
412 };
413 
414 /**
415  * struct cxl_switch_decoder - Switch specific CXL HDM Decoder
416  * @cxld: base cxl_decoder object
417  * @nr_targets: number of elements in @target
418  * @target: active ordered target list in current decoder configuration
419  *
420  * The 'switch' decoder type represents the decoder instances of cxl_port's that
421  * route from the root of a CXL memory decode topology to the endpoints. They
422  * come in two flavors, root-level decoders, statically defined by platform
423  * firmware, and mid-level decoders, where interleave-granularity,
424  * interleave-width, and the target list are mutable.
425  */
426 struct cxl_switch_decoder {
427 	struct cxl_decoder cxld;
428 	int nr_targets;
429 	struct cxl_dport *target[];
430 };
431 
432 struct cxl_root_decoder;
433 typedef struct cxl_dport *(*cxl_calc_hb_fn)(struct cxl_root_decoder *cxlrd,
434 					    int pos);
435 
436 /**
437  * struct cxl_root_decoder - Static platform CXL address decoder
438  * @res: host / parent resource for region allocations
439  * @region_id: region id for next region provisioning event
440  * @calc_hb: which host bridge covers the n'th position by granularity
441  * @platform_data: platform specific configuration data
442  * @range_lock: sync region autodiscovery by address range
443  * @qos_class: QoS performance class cookie
444  * @cxlsd: base cxl switch decoder
445  */
446 struct cxl_root_decoder {
447 	struct resource *res;
448 	atomic_t region_id;
449 	cxl_calc_hb_fn calc_hb;
450 	void *platform_data;
451 	struct mutex range_lock;
452 	int qos_class;
453 	struct cxl_switch_decoder cxlsd;
454 };
455 
456 /*
457  * enum cxl_config_state - State machine for region configuration
458  * @CXL_CONFIG_IDLE: Any sysfs attribute can be written freely
459  * @CXL_CONFIG_INTERLEAVE_ACTIVE: region size has been set, no more
460  * changes to interleave_ways or interleave_granularity
461  * @CXL_CONFIG_ACTIVE: All targets have been added the region is now
462  * active
463  * @CXL_CONFIG_RESET_PENDING: see commit_store()
464  * @CXL_CONFIG_COMMIT: Soft-config has been committed to hardware
465  */
466 enum cxl_config_state {
467 	CXL_CONFIG_IDLE,
468 	CXL_CONFIG_INTERLEAVE_ACTIVE,
469 	CXL_CONFIG_ACTIVE,
470 	CXL_CONFIG_RESET_PENDING,
471 	CXL_CONFIG_COMMIT,
472 };
473 
474 /**
475  * struct cxl_region_params - region settings
476  * @state: allow the driver to lockdown further parameter changes
477  * @uuid: unique id for persistent regions
478  * @interleave_ways: number of endpoints in the region
479  * @interleave_granularity: capacity each endpoint contributes to a stripe
480  * @res: allocated iomem capacity for this region
481  * @targets: active ordered targets in current decoder configuration
482  * @nr_targets: number of targets
483  *
484  * State transitions are protected by the cxl_region_rwsem
485  */
486 struct cxl_region_params {
487 	enum cxl_config_state state;
488 	uuid_t uuid;
489 	int interleave_ways;
490 	int interleave_granularity;
491 	struct resource *res;
492 	struct cxl_endpoint_decoder *targets[CXL_DECODER_MAX_INTERLEAVE];
493 	int nr_targets;
494 };
495 
496 /*
497  * Indicate whether this region has been assembled by autodetection or
498  * userspace assembly. Prevent endpoint decoders outside of automatic
499  * detection from being added to the region.
500  */
501 #define CXL_REGION_F_AUTO 0
502 
503 /*
504  * Require that a committed region successfully complete a teardown once
505  * any of its associated decoders have been torn down. This maintains
506  * the commit state for the region since there are committed decoders,
507  * but blocks cxl_region_probe().
508  */
509 #define CXL_REGION_F_NEEDS_RESET 1
510 
511 /**
512  * struct cxl_region - CXL region
513  * @dev: This region's device
514  * @id: This region's id. Id is globally unique across all regions
515  * @mode: Endpoint decoder allocation / access mode
516  * @type: Endpoint decoder target type
517  * @cxl_nvb: nvdimm bridge for coordinating @cxlr_pmem setup / shutdown
518  * @cxlr_pmem: (for pmem regions) cached copy of the nvdimm bridge
519  * @flags: Region state flags
520  * @params: active + config params for the region
521  * @coord: QoS access coordinates for the region
522  * @memory_notifier: notifier for setting the access coordinates to node
523  */
524 struct cxl_region {
525 	struct device dev;
526 	int id;
527 	enum cxl_decoder_mode mode;
528 	enum cxl_decoder_type type;
529 	struct cxl_nvdimm_bridge *cxl_nvb;
530 	struct cxl_pmem_region *cxlr_pmem;
531 	unsigned long flags;
532 	struct cxl_region_params params;
533 	struct access_coordinate coord[ACCESS_COORDINATE_MAX];
534 	struct notifier_block memory_notifier;
535 };
536 
537 struct cxl_nvdimm_bridge {
538 	int id;
539 	struct device dev;
540 	struct cxl_port *port;
541 	struct nvdimm_bus *nvdimm_bus;
542 	struct nvdimm_bus_descriptor nd_desc;
543 };
544 
545 #define CXL_DEV_ID_LEN 19
546 
547 struct cxl_nvdimm {
548 	struct device dev;
549 	struct cxl_memdev *cxlmd;
550 	u8 dev_id[CXL_DEV_ID_LEN]; /* for nvdimm, string of 'serial' */
551 };
552 
553 struct cxl_pmem_region_mapping {
554 	struct cxl_memdev *cxlmd;
555 	struct cxl_nvdimm *cxl_nvd;
556 	u64 start;
557 	u64 size;
558 	int position;
559 };
560 
561 struct cxl_pmem_region {
562 	struct device dev;
563 	struct cxl_region *cxlr;
564 	struct nd_region *nd_region;
565 	struct range hpa_range;
566 	int nr_mappings;
567 	struct cxl_pmem_region_mapping mapping[];
568 };
569 
570 struct cxl_dax_region {
571 	struct device dev;
572 	struct cxl_region *cxlr;
573 	struct range hpa_range;
574 };
575 
576 /**
577  * struct cxl_port - logical collection of upstream port devices and
578  *		     downstream port devices to construct a CXL memory
579  *		     decode hierarchy.
580  * @dev: this port's device
581  * @uport_dev: PCI or platform device implementing the upstream port capability
582  * @host_bridge: Shortcut to the platform attach point for this port
583  * @id: id for port device-name
584  * @dports: cxl_dport instances referenced by decoders
585  * @endpoints: cxl_ep instances, endpoints that are a descendant of this port
586  * @regions: cxl_region_ref instances, regions mapped by this port
587  * @parent_dport: dport that points to this port in the parent
588  * @decoder_ida: allocator for decoder ids
589  * @reg_map: component and ras register mapping parameters
590  * @nr_dports: number of entries in @dports
591  * @hdm_end: track last allocated HDM decoder instance for allocation ordering
592  * @commit_end: cursor to track highest committed decoder for commit ordering
593  * @dead: last ep has been removed, force port re-creation
594  * @depth: How deep this port is relative to the root. depth 0 is the root.
595  * @cdat: Cached CDAT data
596  * @cdat_available: Should a CDAT attribute be available in sysfs
597  * @pci_latency: Upstream latency in picoseconds
598  */
599 struct cxl_port {
600 	struct device dev;
601 	struct device *uport_dev;
602 	struct device *host_bridge;
603 	int id;
604 	struct xarray dports;
605 	struct xarray endpoints;
606 	struct xarray regions;
607 	struct cxl_dport *parent_dport;
608 	struct ida decoder_ida;
609 	struct cxl_register_map reg_map;
610 	int nr_dports;
611 	int hdm_end;
612 	int commit_end;
613 	bool dead;
614 	unsigned int depth;
615 	struct cxl_cdat {
616 		void *table;
617 		size_t length;
618 	} cdat;
619 	bool cdat_available;
620 	long pci_latency;
621 };
622 
623 /**
624  * struct cxl_root - logical collection of root cxl_port items
625  *
626  * @port: cxl_port member
627  * @ops: cxl root operations
628  */
629 struct cxl_root {
630 	struct cxl_port port;
631 	const struct cxl_root_ops *ops;
632 };
633 
634 static inline struct cxl_root *
635 to_cxl_root(const struct cxl_port *port)
636 {
637 	return container_of(port, struct cxl_root, port);
638 }
639 
640 struct cxl_root_ops {
641 	int (*qos_class)(struct cxl_root *cxl_root,
642 			 struct access_coordinate *coord, int entries,
643 			 int *qos_class);
644 };
645 
646 static inline struct cxl_dport *
647 cxl_find_dport_by_dev(struct cxl_port *port, const struct device *dport_dev)
648 {
649 	return xa_load(&port->dports, (unsigned long)dport_dev);
650 }
651 
652 struct cxl_rcrb_info {
653 	resource_size_t base;
654 	u16 aer_cap;
655 };
656 
657 /**
658  * struct cxl_dport - CXL downstream port
659  * @dport_dev: PCI bridge or firmware device representing the downstream link
660  * @reg_map: component and ras register mapping parameters
661  * @port_id: unique hardware identifier for dport in decoder target list
662  * @rcrb: Data about the Root Complex Register Block layout
663  * @rch: Indicate whether this dport was enumerated in RCH or VH mode
664  * @port: reference to cxl_port that contains this downstream port
665  * @regs: Dport parsed register blocks
666  * @coord: access coordinates (bandwidth and latency performance attributes)
667  * @link_latency: calculated PCIe downstream latency
668  */
669 struct cxl_dport {
670 	struct device *dport_dev;
671 	struct cxl_register_map reg_map;
672 	int port_id;
673 	struct cxl_rcrb_info rcrb;
674 	bool rch;
675 	struct cxl_port *port;
676 	struct cxl_regs regs;
677 	struct access_coordinate coord[ACCESS_COORDINATE_MAX];
678 	long link_latency;
679 };
680 
681 /**
682  * struct cxl_ep - track an endpoint's interest in a port
683  * @ep: device that hosts a generic CXL endpoint (expander or accelerator)
684  * @dport: which dport routes to this endpoint on @port
685  * @next: cxl switch port across the link attached to @dport NULL if
686  *	  attached to an endpoint
687  */
688 struct cxl_ep {
689 	struct device *ep;
690 	struct cxl_dport *dport;
691 	struct cxl_port *next;
692 };
693 
694 /**
695  * struct cxl_region_ref - track a region's interest in a port
696  * @port: point in topology to install this reference
697  * @decoder: decoder assigned for @region in @port
698  * @region: region for this reference
699  * @endpoints: cxl_ep references for region members beneath @port
700  * @nr_targets_set: track how many targets have been programmed during setup
701  * @nr_eps: number of endpoints beneath @port
702  * @nr_targets: number of distinct targets needed to reach @nr_eps
703  */
704 struct cxl_region_ref {
705 	struct cxl_port *port;
706 	struct cxl_decoder *decoder;
707 	struct cxl_region *region;
708 	struct xarray endpoints;
709 	int nr_targets_set;
710 	int nr_eps;
711 	int nr_targets;
712 };
713 
714 /*
715  * The platform firmware device hosting the root is also the top of the
716  * CXL port topology. All other CXL ports have another CXL port as their
717  * parent and their ->uport_dev / host device is out-of-line of the port
718  * ancestry.
719  */
720 static inline bool is_cxl_root(struct cxl_port *port)
721 {
722 	return port->uport_dev == port->dev.parent;
723 }
724 
725 int cxl_num_decoders_committed(struct cxl_port *port);
726 bool is_cxl_port(const struct device *dev);
727 struct cxl_port *to_cxl_port(const struct device *dev);
728 struct pci_bus;
729 int devm_cxl_register_pci_bus(struct device *host, struct device *uport_dev,
730 			      struct pci_bus *bus);
731 struct pci_bus *cxl_port_to_pci_bus(struct cxl_port *port);
732 struct cxl_port *devm_cxl_add_port(struct device *host,
733 				   struct device *uport_dev,
734 				   resource_size_t component_reg_phys,
735 				   struct cxl_dport *parent_dport);
736 struct cxl_root *devm_cxl_add_root(struct device *host,
737 				   const struct cxl_root_ops *ops);
738 struct cxl_root *find_cxl_root(struct cxl_port *port);
739 void put_cxl_root(struct cxl_root *cxl_root);
740 DEFINE_FREE(put_cxl_root, struct cxl_root *, if (_T) put_cxl_root(_T))
741 
742 int devm_cxl_enumerate_ports(struct cxl_memdev *cxlmd);
743 void cxl_bus_rescan(void);
744 void cxl_bus_drain(void);
745 struct cxl_port *cxl_pci_find_port(struct pci_dev *pdev,
746 				   struct cxl_dport **dport);
747 struct cxl_port *cxl_mem_find_port(struct cxl_memdev *cxlmd,
748 				   struct cxl_dport **dport);
749 bool schedule_cxl_memdev_detach(struct cxl_memdev *cxlmd);
750 
751 struct cxl_dport *devm_cxl_add_dport(struct cxl_port *port,
752 				     struct device *dport, int port_id,
753 				     resource_size_t component_reg_phys);
754 struct cxl_dport *devm_cxl_add_rch_dport(struct cxl_port *port,
755 					 struct device *dport_dev, int port_id,
756 					 resource_size_t rcrb);
757 
758 #ifdef CONFIG_PCIEAER_CXL
759 void cxl_setup_parent_dport(struct device *host, struct cxl_dport *dport);
760 #else
761 static inline void cxl_setup_parent_dport(struct device *host,
762 					  struct cxl_dport *dport) { }
763 #endif
764 
765 struct cxl_decoder *to_cxl_decoder(struct device *dev);
766 struct cxl_root_decoder *to_cxl_root_decoder(struct device *dev);
767 struct cxl_switch_decoder *to_cxl_switch_decoder(struct device *dev);
768 struct cxl_endpoint_decoder *to_cxl_endpoint_decoder(struct device *dev);
769 bool is_root_decoder(struct device *dev);
770 bool is_switch_decoder(struct device *dev);
771 bool is_endpoint_decoder(struct device *dev);
772 struct cxl_root_decoder *cxl_root_decoder_alloc(struct cxl_port *port,
773 						unsigned int nr_targets,
774 						cxl_calc_hb_fn calc_hb);
775 struct cxl_dport *cxl_hb_modulo(struct cxl_root_decoder *cxlrd, int pos);
776 struct cxl_switch_decoder *cxl_switch_decoder_alloc(struct cxl_port *port,
777 						    unsigned int nr_targets);
778 int cxl_decoder_add(struct cxl_decoder *cxld, int *target_map);
779 struct cxl_endpoint_decoder *cxl_endpoint_decoder_alloc(struct cxl_port *port);
780 int cxl_decoder_add_locked(struct cxl_decoder *cxld, int *target_map);
781 int cxl_decoder_autoremove(struct device *host, struct cxl_decoder *cxld);
782 int cxl_endpoint_autoremove(struct cxl_memdev *cxlmd, struct cxl_port *endpoint);
783 
784 /**
785  * struct cxl_endpoint_dvsec_info - Cached DVSEC info
786  * @mem_enabled: cached value of mem_enabled in the DVSEC at init time
787  * @ranges: Number of active HDM ranges this device uses.
788  * @port: endpoint port associated with this info instance
789  * @dvsec_range: cached attributes of the ranges in the DVSEC, PCIE_DEVICE
790  */
791 struct cxl_endpoint_dvsec_info {
792 	bool mem_enabled;
793 	int ranges;
794 	struct cxl_port *port;
795 	struct range dvsec_range[2];
796 };
797 
798 struct cxl_hdm;
799 struct cxl_hdm *devm_cxl_setup_hdm(struct cxl_port *port,
800 				   struct cxl_endpoint_dvsec_info *info);
801 int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm,
802 				struct cxl_endpoint_dvsec_info *info);
803 int devm_cxl_add_passthrough_decoder(struct cxl_port *port);
804 int cxl_dvsec_rr_decode(struct device *dev, int dvsec,
805 			struct cxl_endpoint_dvsec_info *info);
806 
807 bool is_cxl_region(struct device *dev);
808 
809 extern struct bus_type cxl_bus_type;
810 
811 struct cxl_driver {
812 	const char *name;
813 	int (*probe)(struct device *dev);
814 	void (*remove)(struct device *dev);
815 	struct device_driver drv;
816 	int id;
817 };
818 
819 static inline struct cxl_driver *to_cxl_drv(struct device_driver *drv)
820 {
821 	return container_of(drv, struct cxl_driver, drv);
822 }
823 
824 int __cxl_driver_register(struct cxl_driver *cxl_drv, struct module *owner,
825 			  const char *modname);
826 #define cxl_driver_register(x) __cxl_driver_register(x, THIS_MODULE, KBUILD_MODNAME)
827 void cxl_driver_unregister(struct cxl_driver *cxl_drv);
828 
829 #define module_cxl_driver(__cxl_driver) \
830 	module_driver(__cxl_driver, cxl_driver_register, cxl_driver_unregister)
831 
832 #define CXL_DEVICE_NVDIMM_BRIDGE	1
833 #define CXL_DEVICE_NVDIMM		2
834 #define CXL_DEVICE_PORT			3
835 #define CXL_DEVICE_ROOT			4
836 #define CXL_DEVICE_MEMORY_EXPANDER	5
837 #define CXL_DEVICE_REGION		6
838 #define CXL_DEVICE_PMEM_REGION		7
839 #define CXL_DEVICE_DAX_REGION		8
840 #define CXL_DEVICE_PMU			9
841 
842 #define MODULE_ALIAS_CXL(type) MODULE_ALIAS("cxl:t" __stringify(type) "*")
843 #define CXL_MODALIAS_FMT "cxl:t%d"
844 
845 struct cxl_nvdimm_bridge *to_cxl_nvdimm_bridge(struct device *dev);
846 struct cxl_nvdimm_bridge *devm_cxl_add_nvdimm_bridge(struct device *host,
847 						     struct cxl_port *port);
848 struct cxl_nvdimm *to_cxl_nvdimm(struct device *dev);
849 bool is_cxl_nvdimm(struct device *dev);
850 bool is_cxl_nvdimm_bridge(struct device *dev);
851 int devm_cxl_add_nvdimm(struct cxl_memdev *cxlmd);
852 struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_memdev *cxlmd);
853 
854 #ifdef CONFIG_CXL_REGION
855 bool is_cxl_pmem_region(struct device *dev);
856 struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev);
857 int cxl_add_to_region(struct cxl_port *root,
858 		      struct cxl_endpoint_decoder *cxled);
859 struct cxl_dax_region *to_cxl_dax_region(struct device *dev);
860 #else
861 static inline bool is_cxl_pmem_region(struct device *dev)
862 {
863 	return false;
864 }
865 static inline struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev)
866 {
867 	return NULL;
868 }
869 static inline int cxl_add_to_region(struct cxl_port *root,
870 				    struct cxl_endpoint_decoder *cxled)
871 {
872 	return 0;
873 }
874 static inline struct cxl_dax_region *to_cxl_dax_region(struct device *dev)
875 {
876 	return NULL;
877 }
878 #endif
879 
880 void cxl_endpoint_parse_cdat(struct cxl_port *port);
881 void cxl_switch_parse_cdat(struct cxl_port *port);
882 
883 int cxl_endpoint_get_perf_coordinates(struct cxl_port *port,
884 				      struct access_coordinate *coord);
885 void cxl_region_perf_data_calculate(struct cxl_region *cxlr,
886 				    struct cxl_endpoint_decoder *cxled);
887 
888 void cxl_memdev_update_perf(struct cxl_memdev *cxlmd);
889 
890 void cxl_coordinates_combine(struct access_coordinate *out,
891 			     struct access_coordinate *c1,
892 			     struct access_coordinate *c2);
893 
894 /*
895  * Unit test builds overrides this to __weak, find the 'strong' version
896  * of these symbols in tools/testing/cxl/.
897  */
898 #ifndef __mock
899 #define __mock static
900 #endif
901 
902 #endif /* __CXL_H__ */
903