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 extern const struct nvdimm_security_ops *cxl_security_ops;
16 
17 /**
18  * DOC: cxl objects
19  *
20  * The CXL core objects like ports, decoders, and regions are shared
21  * between the subsystem drivers cxl_acpi, cxl_pci, and core drivers
22  * (port-driver, region-driver, nvdimm object-drivers... etc).
23  */
24 
25 /* CXL 2.0 8.2.4 CXL Component Register Layout and Definition */
26 #define CXL_COMPONENT_REG_BLOCK_SIZE SZ_64K
27 
28 /* CXL 2.0 8.2.5 CXL.cache and CXL.mem Registers*/
29 #define CXL_CM_OFFSET 0x1000
30 #define CXL_CM_CAP_HDR_OFFSET 0x0
31 #define   CXL_CM_CAP_HDR_ID_MASK GENMASK(15, 0)
32 #define     CM_CAP_HDR_CAP_ID 1
33 #define   CXL_CM_CAP_HDR_VERSION_MASK GENMASK(19, 16)
34 #define     CM_CAP_HDR_CAP_VERSION 1
35 #define   CXL_CM_CAP_HDR_CACHE_MEM_VERSION_MASK GENMASK(23, 20)
36 #define     CM_CAP_HDR_CACHE_MEM_VERSION 1
37 #define   CXL_CM_CAP_HDR_ARRAY_SIZE_MASK GENMASK(31, 24)
38 #define CXL_CM_CAP_PTR_MASK GENMASK(31, 20)
39 
40 #define   CXL_CM_CAP_CAP_ID_RAS 0x2
41 #define   CXL_CM_CAP_CAP_ID_HDM 0x5
42 #define   CXL_CM_CAP_CAP_HDM_VERSION 1
43 
44 /* HDM decoders CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure */
45 #define CXL_HDM_DECODER_CAP_OFFSET 0x0
46 #define   CXL_HDM_DECODER_COUNT_MASK GENMASK(3, 0)
47 #define   CXL_HDM_DECODER_TARGET_COUNT_MASK GENMASK(7, 4)
48 #define   CXL_HDM_DECODER_INTERLEAVE_11_8 BIT(8)
49 #define   CXL_HDM_DECODER_INTERLEAVE_14_12 BIT(9)
50 #define   CXL_HDM_DECODER_INTERLEAVE_3_6_12_WAY BIT(11)
51 #define   CXL_HDM_DECODER_INTERLEAVE_16_WAY BIT(12)
52 #define CXL_HDM_DECODER_CTRL_OFFSET 0x4
53 #define   CXL_HDM_DECODER_ENABLE BIT(1)
54 #define CXL_HDM_DECODER0_BASE_LOW_OFFSET(i) (0x20 * (i) + 0x10)
55 #define CXL_HDM_DECODER0_BASE_HIGH_OFFSET(i) (0x20 * (i) + 0x14)
56 #define CXL_HDM_DECODER0_SIZE_LOW_OFFSET(i) (0x20 * (i) + 0x18)
57 #define CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(i) (0x20 * (i) + 0x1c)
58 #define CXL_HDM_DECODER0_CTRL_OFFSET(i) (0x20 * (i) + 0x20)
59 #define   CXL_HDM_DECODER0_CTRL_IG_MASK GENMASK(3, 0)
60 #define   CXL_HDM_DECODER0_CTRL_IW_MASK GENMASK(7, 4)
61 #define   CXL_HDM_DECODER0_CTRL_LOCK BIT(8)
62 #define   CXL_HDM_DECODER0_CTRL_COMMIT BIT(9)
63 #define   CXL_HDM_DECODER0_CTRL_COMMITTED BIT(10)
64 #define   CXL_HDM_DECODER0_CTRL_COMMIT_ERROR BIT(11)
65 #define   CXL_HDM_DECODER0_CTRL_HOSTONLY BIT(12)
66 #define CXL_HDM_DECODER0_TL_LOW(i) (0x20 * (i) + 0x24)
67 #define CXL_HDM_DECODER0_TL_HIGH(i) (0x20 * (i) + 0x28)
68 #define CXL_HDM_DECODER0_SKIP_LOW(i) CXL_HDM_DECODER0_TL_LOW(i)
69 #define CXL_HDM_DECODER0_SKIP_HIGH(i) CXL_HDM_DECODER0_TL_HIGH(i)
70 
71 /* HDM decoder control register constants CXL 3.0 8.2.5.19.7 */
72 #define CXL_DECODER_MIN_GRANULARITY 256
73 #define CXL_DECODER_MAX_ENCODED_IG 6
74 
75 static inline int cxl_hdm_decoder_count(u32 cap_hdr)
76 {
77 	int val = FIELD_GET(CXL_HDM_DECODER_COUNT_MASK, cap_hdr);
78 
79 	return val ? val * 2 : 1;
80 }
81 
82 /* Encode defined in CXL 2.0 8.2.5.12.7 HDM Decoder Control Register */
83 static inline int eig_to_granularity(u16 eig, unsigned int *granularity)
84 {
85 	if (eig > CXL_DECODER_MAX_ENCODED_IG)
86 		return -EINVAL;
87 	*granularity = CXL_DECODER_MIN_GRANULARITY << eig;
88 	return 0;
89 }
90 
91 /* Encode defined in CXL ECN "3, 6, 12 and 16-way memory Interleaving" */
92 static inline int eiw_to_ways(u8 eiw, unsigned int *ways)
93 {
94 	switch (eiw) {
95 	case 0 ... 4:
96 		*ways = 1 << eiw;
97 		break;
98 	case 8 ... 10:
99 		*ways = 3 << (eiw - 8);
100 		break;
101 	default:
102 		return -EINVAL;
103 	}
104 
105 	return 0;
106 }
107 
108 static inline int granularity_to_eig(int granularity, u16 *eig)
109 {
110 	if (granularity > SZ_16K || granularity < CXL_DECODER_MIN_GRANULARITY ||
111 	    !is_power_of_2(granularity))
112 		return -EINVAL;
113 	*eig = ilog2(granularity) - 8;
114 	return 0;
115 }
116 
117 static inline int ways_to_eiw(unsigned int ways, u8 *eiw)
118 {
119 	if (ways > 16)
120 		return -EINVAL;
121 	if (is_power_of_2(ways)) {
122 		*eiw = ilog2(ways);
123 		return 0;
124 	}
125 	if (ways % 3)
126 		return -EINVAL;
127 	ways /= 3;
128 	if (!is_power_of_2(ways))
129 		return -EINVAL;
130 	*eiw = ilog2(ways) + 8;
131 	return 0;
132 }
133 
134 /* RAS Registers CXL 2.0 8.2.5.9 CXL RAS Capability Structure */
135 #define CXL_RAS_UNCORRECTABLE_STATUS_OFFSET 0x0
136 #define   CXL_RAS_UNCORRECTABLE_STATUS_MASK (GENMASK(16, 14) | GENMASK(11, 0))
137 #define CXL_RAS_UNCORRECTABLE_MASK_OFFSET 0x4
138 #define   CXL_RAS_UNCORRECTABLE_MASK_MASK (GENMASK(16, 14) | GENMASK(11, 0))
139 #define   CXL_RAS_UNCORRECTABLE_MASK_F256B_MASK BIT(8)
140 #define CXL_RAS_UNCORRECTABLE_SEVERITY_OFFSET 0x8
141 #define   CXL_RAS_UNCORRECTABLE_SEVERITY_MASK (GENMASK(16, 14) | GENMASK(11, 0))
142 #define CXL_RAS_CORRECTABLE_STATUS_OFFSET 0xC
143 #define   CXL_RAS_CORRECTABLE_STATUS_MASK GENMASK(6, 0)
144 #define CXL_RAS_CORRECTABLE_MASK_OFFSET 0x10
145 #define   CXL_RAS_CORRECTABLE_MASK_MASK GENMASK(6, 0)
146 #define CXL_RAS_CAP_CONTROL_OFFSET 0x14
147 #define CXL_RAS_CAP_CONTROL_FE_MASK GENMASK(5, 0)
148 #define CXL_RAS_HEADER_LOG_OFFSET 0x18
149 #define CXL_RAS_CAPABILITY_LENGTH 0x58
150 #define CXL_HEADERLOG_SIZE SZ_512
151 #define CXL_HEADERLOG_SIZE_U32 SZ_512 / sizeof(u32)
152 
153 /* CXL 2.0 8.2.8.1 Device Capabilities Array Register */
154 #define CXLDEV_CAP_ARRAY_OFFSET 0x0
155 #define   CXLDEV_CAP_ARRAY_CAP_ID 0
156 #define   CXLDEV_CAP_ARRAY_ID_MASK GENMASK_ULL(15, 0)
157 #define   CXLDEV_CAP_ARRAY_COUNT_MASK GENMASK_ULL(47, 32)
158 /* CXL 2.0 8.2.8.2 CXL Device Capability Header Register */
159 #define CXLDEV_CAP_HDR_CAP_ID_MASK GENMASK(15, 0)
160 /* CXL 2.0 8.2.8.2.1 CXL Device Capabilities */
161 #define CXLDEV_CAP_CAP_ID_DEVICE_STATUS 0x1
162 #define CXLDEV_CAP_CAP_ID_PRIMARY_MAILBOX 0x2
163 #define CXLDEV_CAP_CAP_ID_SECONDARY_MAILBOX 0x3
164 #define CXLDEV_CAP_CAP_ID_MEMDEV 0x4000
165 
166 /* CXL 3.0 8.2.8.3.1 Event Status Register */
167 #define CXLDEV_DEV_EVENT_STATUS_OFFSET		0x00
168 #define CXLDEV_EVENT_STATUS_INFO		BIT(0)
169 #define CXLDEV_EVENT_STATUS_WARN		BIT(1)
170 #define CXLDEV_EVENT_STATUS_FAIL		BIT(2)
171 #define CXLDEV_EVENT_STATUS_FATAL		BIT(3)
172 
173 #define CXLDEV_EVENT_STATUS_ALL (CXLDEV_EVENT_STATUS_INFO |	\
174 				 CXLDEV_EVENT_STATUS_WARN |	\
175 				 CXLDEV_EVENT_STATUS_FAIL |	\
176 				 CXLDEV_EVENT_STATUS_FATAL)
177 
178 /* CXL rev 3.0 section 8.2.9.2.4; Table 8-52 */
179 #define CXLDEV_EVENT_INT_MODE_MASK	GENMASK(1, 0)
180 #define CXLDEV_EVENT_INT_MSGNUM_MASK	GENMASK(7, 4)
181 
182 /* CXL 2.0 8.2.8.4 Mailbox Registers */
183 #define CXLDEV_MBOX_CAPS_OFFSET 0x00
184 #define   CXLDEV_MBOX_CAP_PAYLOAD_SIZE_MASK GENMASK(4, 0)
185 #define   CXLDEV_MBOX_CAP_BG_CMD_IRQ BIT(6)
186 #define   CXLDEV_MBOX_CAP_IRQ_MSGNUM_MASK GENMASK(10, 7)
187 #define CXLDEV_MBOX_CTRL_OFFSET 0x04
188 #define   CXLDEV_MBOX_CTRL_DOORBELL BIT(0)
189 #define   CXLDEV_MBOX_CTRL_BG_CMD_IRQ BIT(2)
190 #define CXLDEV_MBOX_CMD_OFFSET 0x08
191 #define   CXLDEV_MBOX_CMD_COMMAND_OPCODE_MASK GENMASK_ULL(15, 0)
192 #define   CXLDEV_MBOX_CMD_PAYLOAD_LENGTH_MASK GENMASK_ULL(36, 16)
193 #define CXLDEV_MBOX_STATUS_OFFSET 0x10
194 #define   CXLDEV_MBOX_STATUS_BG_CMD BIT(0)
195 #define   CXLDEV_MBOX_STATUS_RET_CODE_MASK GENMASK_ULL(47, 32)
196 #define CXLDEV_MBOX_BG_CMD_STATUS_OFFSET 0x18
197 #define   CXLDEV_MBOX_BG_CMD_COMMAND_OPCODE_MASK GENMASK_ULL(15, 0)
198 #define   CXLDEV_MBOX_BG_CMD_COMMAND_PCT_MASK GENMASK_ULL(22, 16)
199 #define   CXLDEV_MBOX_BG_CMD_COMMAND_RC_MASK GENMASK_ULL(47, 32)
200 #define   CXLDEV_MBOX_BG_CMD_COMMAND_VENDOR_MASK GENMASK_ULL(63, 48)
201 #define CXLDEV_MBOX_PAYLOAD_OFFSET 0x20
202 
203 /*
204  * Using struct_group() allows for per register-block-type helper routines,
205  * without requiring block-type agnostic code to include the prefix.
206  */
207 struct cxl_regs {
208 	/*
209 	 * Common set of CXL Component register block base pointers
210 	 * @hdm_decoder: CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure
211 	 * @ras: CXL 2.0 8.2.5.9 CXL RAS Capability Structure
212 	 */
213 	struct_group_tagged(cxl_component_regs, component,
214 		void __iomem *hdm_decoder;
215 		void __iomem *ras;
216 	);
217 	/*
218 	 * Common set of CXL Device register block base pointers
219 	 * @status: CXL 2.0 8.2.8.3 Device Status Registers
220 	 * @mbox: CXL 2.0 8.2.8.4 Mailbox Registers
221 	 * @memdev: CXL 2.0 8.2.8.5 Memory Device Registers
222 	 */
223 	struct_group_tagged(cxl_device_regs, device_regs,
224 		void __iomem *status, *mbox, *memdev;
225 	);
226 
227 	struct_group_tagged(cxl_pmu_regs, pmu_regs,
228 		void __iomem *pmu;
229 	);
230 
231 	/*
232 	 * RCH downstream port specific RAS register
233 	 * @aer: CXL 3.0 8.2.1.1 RCH Downstream Port RCRB
234 	 */
235 	struct_group_tagged(cxl_rch_regs, rch_regs,
236 		void __iomem *dport_aer;
237 	);
238 
239 	/*
240 	 * RCD upstream port specific PCIe cap register
241 	 * @pcie_cap: CXL 3.0 8.2.1.2 RCD Upstream Port RCRB
242 	 */
243 	struct_group_tagged(cxl_rcd_regs, rcd_regs,
244 		void __iomem *rcd_pcie_cap;
245 	);
246 };
247 
248 struct cxl_reg_map {
249 	bool valid;
250 	int id;
251 	unsigned long offset;
252 	unsigned long size;
253 };
254 
255 struct cxl_component_reg_map {
256 	struct cxl_reg_map hdm_decoder;
257 	struct cxl_reg_map ras;
258 };
259 
260 struct cxl_device_reg_map {
261 	struct cxl_reg_map status;
262 	struct cxl_reg_map mbox;
263 	struct cxl_reg_map memdev;
264 };
265 
266 struct cxl_pmu_reg_map {
267 	struct cxl_reg_map pmu;
268 };
269 
270 /**
271  * struct cxl_register_map - DVSEC harvested register block mapping parameters
272  * @host: device for devm operations and logging
273  * @base: virtual base of the register-block-BAR + @block_offset
274  * @resource: physical resource base of the register block
275  * @max_size: maximum mapping size to perform register search
276  * @reg_type: see enum cxl_regloc_type
277  * @component_map: cxl_reg_map for component registers
278  * @device_map: cxl_reg_maps for device registers
279  * @pmu_map: cxl_reg_maps for CXL Performance Monitoring Units
280  */
281 struct cxl_register_map {
282 	struct device *host;
283 	void __iomem *base;
284 	resource_size_t resource;
285 	resource_size_t max_size;
286 	u8 reg_type;
287 	union {
288 		struct cxl_component_reg_map component_map;
289 		struct cxl_device_reg_map device_map;
290 		struct cxl_pmu_reg_map pmu_map;
291 	};
292 };
293 
294 void cxl_probe_component_regs(struct device *dev, void __iomem *base,
295 			      struct cxl_component_reg_map *map);
296 void cxl_probe_device_regs(struct device *dev, void __iomem *base,
297 			   struct cxl_device_reg_map *map);
298 int cxl_map_component_regs(const struct cxl_register_map *map,
299 			   struct cxl_component_regs *regs,
300 			   unsigned long map_mask);
301 int cxl_map_device_regs(const struct cxl_register_map *map,
302 			struct cxl_device_regs *regs);
303 int cxl_map_pmu_regs(struct cxl_register_map *map, struct cxl_pmu_regs *regs);
304 
305 #define CXL_INSTANCES_COUNT -1
306 enum cxl_regloc_type;
307 int cxl_count_regblock(struct pci_dev *pdev, enum cxl_regloc_type type);
308 int cxl_find_regblock_instance(struct pci_dev *pdev, enum cxl_regloc_type type,
309 			       struct cxl_register_map *map, unsigned int index);
310 int cxl_find_regblock(struct pci_dev *pdev, enum cxl_regloc_type type,
311 		      struct cxl_register_map *map);
312 int cxl_setup_regs(struct cxl_register_map *map);
313 struct cxl_dport;
314 resource_size_t cxl_rcd_component_reg_phys(struct device *dev,
315 					   struct cxl_dport *dport);
316 int cxl_dport_map_rcd_linkcap(struct pci_dev *pdev, struct cxl_dport *dport);
317 
318 #define CXL_RESOURCE_NONE ((resource_size_t) -1)
319 #define CXL_TARGET_STRLEN 20
320 
321 /*
322  * cxl_decoder flags that define the type of memory / devices this
323  * decoder supports as well as configuration lock status See "CXL 2.0
324  * 8.2.5.12.7 CXL HDM Decoder 0 Control Register" for details.
325  * Additionally indicate whether decoder settings were autodetected,
326  * user customized.
327  */
328 #define CXL_DECODER_F_RAM   BIT(0)
329 #define CXL_DECODER_F_PMEM  BIT(1)
330 #define CXL_DECODER_F_TYPE2 BIT(2)
331 #define CXL_DECODER_F_TYPE3 BIT(3)
332 #define CXL_DECODER_F_LOCK  BIT(4)
333 #define CXL_DECODER_F_ENABLE    BIT(5)
334 #define CXL_DECODER_F_MASK  GENMASK(5, 0)
335 
336 enum cxl_decoder_type {
337 	CXL_DECODER_DEVMEM = 2,
338 	CXL_DECODER_HOSTONLYMEM = 3,
339 };
340 
341 /*
342  * Current specification goes up to 8, double that seems a reasonable
343  * software max for the foreseeable future
344  */
345 #define CXL_DECODER_MAX_INTERLEAVE 16
346 
347 #define CXL_QOS_CLASS_INVALID -1
348 
349 /**
350  * struct cxl_decoder - Common CXL HDM Decoder Attributes
351  * @dev: this decoder's device
352  * @id: kernel device name id
353  * @hpa_range: Host physical address range mapped by this decoder
354  * @interleave_ways: number of cxl_dports in this decode
355  * @interleave_granularity: data stride per dport
356  * @target_type: accelerator vs expander (type2 vs type3) selector
357  * @region: currently assigned region for this decoder
358  * @flags: memory type capabilities and locking
359  * @commit: device/decoder-type specific callback to commit settings to hw
360  * @reset: device/decoder-type specific callback to reset hw settings
361 */
362 struct cxl_decoder {
363 	struct device dev;
364 	int id;
365 	struct range hpa_range;
366 	int interleave_ways;
367 	int interleave_granularity;
368 	enum cxl_decoder_type target_type;
369 	struct cxl_region *region;
370 	unsigned long flags;
371 	int (*commit)(struct cxl_decoder *cxld);
372 	void (*reset)(struct cxl_decoder *cxld);
373 };
374 
375 /*
376  * Track whether this decoder is reserved for region autodiscovery, or
377  * free for userspace provisioning.
378  */
379 enum cxl_decoder_state {
380 	CXL_DECODER_STATE_MANUAL,
381 	CXL_DECODER_STATE_AUTO,
382 };
383 
384 /**
385  * struct cxl_endpoint_decoder - Endpoint  / SPA to DPA decoder
386  * @cxld: base cxl_decoder_object
387  * @dpa_res: actively claimed DPA span of this decoder
388  * @skip: offset into @dpa_res where @cxld.hpa_range maps
389  * @state: autodiscovery state
390  * @part: partition index this decoder maps
391  * @pos: interleave position in @cxld.region
392  */
393 struct cxl_endpoint_decoder {
394 	struct cxl_decoder cxld;
395 	struct resource *dpa_res;
396 	resource_size_t skip;
397 	enum cxl_decoder_state state;
398 	int part;
399 	int pos;
400 };
401 
402 /**
403  * struct cxl_switch_decoder - Switch specific CXL HDM Decoder
404  * @cxld: base cxl_decoder object
405  * @nr_targets: number of elements in @target
406  * @target: active ordered target list in current decoder configuration
407  *
408  * The 'switch' decoder type represents the decoder instances of cxl_port's that
409  * route from the root of a CXL memory decode topology to the endpoints. They
410  * come in two flavors, root-level decoders, statically defined by platform
411  * firmware, and mid-level decoders, where interleave-granularity,
412  * interleave-width, and the target list are mutable.
413  */
414 struct cxl_switch_decoder {
415 	struct cxl_decoder cxld;
416 	int nr_targets;
417 	struct cxl_dport *target[];
418 };
419 
420 struct cxl_root_decoder;
421 typedef u64 (*cxl_hpa_to_spa_fn)(struct cxl_root_decoder *cxlrd, u64 hpa);
422 
423 /**
424  * struct cxl_root_decoder - Static platform CXL address decoder
425  * @res: host / parent resource for region allocations
426  * @region_id: region id for next region provisioning event
427  * @hpa_to_spa: translate CXL host-physical-address to Platform system-physical-address
428  * @platform_data: platform specific configuration data
429  * @range_lock: sync region autodiscovery by address range
430  * @qos_class: QoS performance class cookie
431  * @cxlsd: base cxl switch decoder
432  */
433 struct cxl_root_decoder {
434 	struct resource *res;
435 	atomic_t region_id;
436 	cxl_hpa_to_spa_fn hpa_to_spa;
437 	void *platform_data;
438 	struct mutex range_lock;
439 	int qos_class;
440 	struct cxl_switch_decoder cxlsd;
441 };
442 
443 /*
444  * enum cxl_config_state - State machine for region configuration
445  * @CXL_CONFIG_IDLE: Any sysfs attribute can be written freely
446  * @CXL_CONFIG_INTERLEAVE_ACTIVE: region size has been set, no more
447  * changes to interleave_ways or interleave_granularity
448  * @CXL_CONFIG_ACTIVE: All targets have been added the region is now
449  * active
450  * @CXL_CONFIG_RESET_PENDING: see commit_store()
451  * @CXL_CONFIG_COMMIT: Soft-config has been committed to hardware
452  */
453 enum cxl_config_state {
454 	CXL_CONFIG_IDLE,
455 	CXL_CONFIG_INTERLEAVE_ACTIVE,
456 	CXL_CONFIG_ACTIVE,
457 	CXL_CONFIG_RESET_PENDING,
458 	CXL_CONFIG_COMMIT,
459 };
460 
461 /**
462  * struct cxl_region_params - region settings
463  * @state: allow the driver to lockdown further parameter changes
464  * @uuid: unique id for persistent regions
465  * @interleave_ways: number of endpoints in the region
466  * @interleave_granularity: capacity each endpoint contributes to a stripe
467  * @res: allocated iomem capacity for this region
468  * @targets: active ordered targets in current decoder configuration
469  * @nr_targets: number of targets
470  * @cache_size: extended linear cache size if exists, otherwise zero.
471  *
472  * State transitions are protected by the cxl_region_rwsem
473  */
474 struct cxl_region_params {
475 	enum cxl_config_state state;
476 	uuid_t uuid;
477 	int interleave_ways;
478 	int interleave_granularity;
479 	struct resource *res;
480 	struct cxl_endpoint_decoder *targets[CXL_DECODER_MAX_INTERLEAVE];
481 	int nr_targets;
482 	resource_size_t cache_size;
483 };
484 
485 enum cxl_partition_mode {
486 	CXL_PARTMODE_RAM,
487 	CXL_PARTMODE_PMEM,
488 };
489 
490 /*
491  * Indicate whether this region has been assembled by autodetection or
492  * userspace assembly. Prevent endpoint decoders outside of automatic
493  * detection from being added to the region.
494  */
495 #define CXL_REGION_F_AUTO 0
496 
497 /*
498  * Require that a committed region successfully complete a teardown once
499  * any of its associated decoders have been torn down. This maintains
500  * the commit state for the region since there are committed decoders,
501  * but blocks cxl_region_probe().
502  */
503 #define CXL_REGION_F_NEEDS_RESET 1
504 
505 /**
506  * struct cxl_region - CXL region
507  * @dev: This region's device
508  * @id: This region's id. Id is globally unique across all regions
509  * @mode: Operational mode of the mapped capacity
510  * @type: Endpoint decoder target type
511  * @cxl_nvb: nvdimm bridge for coordinating @cxlr_pmem setup / shutdown
512  * @cxlr_pmem: (for pmem regions) cached copy of the nvdimm bridge
513  * @flags: Region state flags
514  * @params: active + config params for the region
515  * @coord: QoS access coordinates for the region
516  * @memory_notifier: notifier for setting the access coordinates to node
517  * @adist_notifier: notifier for calculating the abstract distance of node
518  */
519 struct cxl_region {
520 	struct device dev;
521 	int id;
522 	enum cxl_partition_mode mode;
523 	enum cxl_decoder_type type;
524 	struct cxl_nvdimm_bridge *cxl_nvb;
525 	struct cxl_pmem_region *cxlr_pmem;
526 	unsigned long flags;
527 	struct cxl_region_params params;
528 	struct access_coordinate coord[ACCESS_COORDINATE_MAX];
529 	struct notifier_block memory_notifier;
530 	struct notifier_block adist_notifier;
531 };
532 
533 struct cxl_nvdimm_bridge {
534 	int id;
535 	struct device dev;
536 	struct cxl_port *port;
537 	struct nvdimm_bus *nvdimm_bus;
538 	struct nvdimm_bus_descriptor nd_desc;
539 };
540 
541 #define CXL_DEV_ID_LEN 19
542 
543 struct cxl_nvdimm {
544 	struct device dev;
545 	struct cxl_memdev *cxlmd;
546 	u8 dev_id[CXL_DEV_ID_LEN]; /* for nvdimm, string of 'serial' */
547 	u64 dirty_shutdowns;
548 };
549 
550 struct cxl_pmem_region_mapping {
551 	struct cxl_memdev *cxlmd;
552 	struct cxl_nvdimm *cxl_nvd;
553 	u64 start;
554 	u64 size;
555 	int position;
556 };
557 
558 struct cxl_pmem_region {
559 	struct device dev;
560 	struct cxl_region *cxlr;
561 	struct nd_region *nd_region;
562 	struct range hpa_range;
563 	int nr_mappings;
564 	struct cxl_pmem_region_mapping mapping[];
565 };
566 
567 struct cxl_dax_region {
568 	struct device dev;
569 	struct cxl_region *cxlr;
570 	struct range hpa_range;
571 };
572 
573 /**
574  * struct cxl_port - logical collection of upstream port devices and
575  *		     downstream port devices to construct a CXL memory
576  *		     decode hierarchy.
577  * @dev: this port's device
578  * @uport_dev: PCI or platform device implementing the upstream port capability
579  * @host_bridge: Shortcut to the platform attach point for this port
580  * @id: id for port device-name
581  * @dports: cxl_dport instances referenced by decoders
582  * @endpoints: cxl_ep instances, endpoints that are a descendant of this port
583  * @regions: cxl_region_ref instances, regions mapped by this port
584  * @parent_dport: dport that points to this port in the parent
585  * @decoder_ida: allocator for decoder ids
586  * @reg_map: component and ras register mapping parameters
587  * @nr_dports: number of entries in @dports
588  * @hdm_end: track last allocated HDM decoder instance for allocation ordering
589  * @commit_end: cursor to track highest committed decoder for commit ordering
590  * @dead: last ep has been removed, force port re-creation
591  * @depth: How deep this port is relative to the root. depth 0 is the root.
592  * @cdat: Cached CDAT data
593  * @cdat_available: Should a CDAT attribute be available in sysfs
594  * @pci_latency: Upstream latency in picoseconds
595  */
596 struct cxl_port {
597 	struct device dev;
598 	struct device *uport_dev;
599 	struct device *host_bridge;
600 	int id;
601 	struct xarray dports;
602 	struct xarray endpoints;
603 	struct xarray regions;
604 	struct cxl_dport *parent_dport;
605 	struct ida decoder_ida;
606 	struct cxl_register_map reg_map;
607 	int nr_dports;
608 	int hdm_end;
609 	int commit_end;
610 	bool dead;
611 	unsigned int depth;
612 	struct cxl_cdat {
613 		void *table;
614 		size_t length;
615 	} cdat;
616 	bool cdat_available;
617 	long pci_latency;
618 };
619 
620 /**
621  * struct cxl_root - logical collection of root cxl_port items
622  *
623  * @port: cxl_port member
624  * @ops: cxl root operations
625  */
626 struct cxl_root {
627 	struct cxl_port port;
628 	const struct cxl_root_ops *ops;
629 };
630 
631 static inline struct cxl_root *
632 to_cxl_root(const struct cxl_port *port)
633 {
634 	return container_of(port, struct cxl_root, port);
635 }
636 
637 struct cxl_root_ops {
638 	int (*qos_class)(struct cxl_root *cxl_root,
639 			 struct access_coordinate *coord, int entries,
640 			 int *qos_class);
641 };
642 
643 static inline struct cxl_dport *
644 cxl_find_dport_by_dev(struct cxl_port *port, const struct device *dport_dev)
645 {
646 	return xa_load(&port->dports, (unsigned long)dport_dev);
647 }
648 
649 struct cxl_rcrb_info {
650 	resource_size_t base;
651 	u16 aer_cap;
652 };
653 
654 /**
655  * struct cxl_dport - CXL downstream port
656  * @dport_dev: PCI bridge or firmware device representing the downstream link
657  * @reg_map: component and ras register mapping parameters
658  * @port_id: unique hardware identifier for dport in decoder target list
659  * @rcrb: Data about the Root Complex Register Block layout
660  * @rch: Indicate whether this dport was enumerated in RCH or VH mode
661  * @port: reference to cxl_port that contains this downstream port
662  * @regs: Dport parsed register blocks
663  * @coord: access coordinates (bandwidth and latency performance attributes)
664  * @link_latency: calculated PCIe downstream latency
665  * @gpf_dvsec: Cached GPF port DVSEC
666  */
667 struct cxl_dport {
668 	struct device *dport_dev;
669 	struct cxl_register_map reg_map;
670 	int port_id;
671 	struct cxl_rcrb_info rcrb;
672 	bool rch;
673 	struct cxl_port *port;
674 	struct cxl_regs regs;
675 	struct access_coordinate coord[ACCESS_COORDINATE_MAX];
676 	long link_latency;
677 	int gpf_dvsec;
678 };
679 
680 /**
681  * struct cxl_ep - track an endpoint's interest in a port
682  * @ep: device that hosts a generic CXL endpoint (expander or accelerator)
683  * @dport: which dport routes to this endpoint on @port
684  * @next: cxl switch port across the link attached to @dport NULL if
685  *	  attached to an endpoint
686  */
687 struct cxl_ep {
688 	struct device *ep;
689 	struct cxl_dport *dport;
690 	struct cxl_port *next;
691 };
692 
693 /**
694  * struct cxl_region_ref - track a region's interest in a port
695  * @port: point in topology to install this reference
696  * @decoder: decoder assigned for @region in @port
697  * @region: region for this reference
698  * @endpoints: cxl_ep references for region members beneath @port
699  * @nr_targets_set: track how many targets have been programmed during setup
700  * @nr_eps: number of endpoints beneath @port
701  * @nr_targets: number of distinct targets needed to reach @nr_eps
702  */
703 struct cxl_region_ref {
704 	struct cxl_port *port;
705 	struct cxl_decoder *decoder;
706 	struct cxl_region *region;
707 	struct xarray endpoints;
708 	int nr_targets_set;
709 	int nr_eps;
710 	int nr_targets;
711 };
712 
713 /*
714  * The platform firmware device hosting the root is also the top of the
715  * CXL port topology. All other CXL ports have another CXL port as their
716  * parent and their ->uport_dev / host device is out-of-line of the port
717  * ancestry.
718  */
719 static inline bool is_cxl_root(struct cxl_port *port)
720 {
721 	return port->uport_dev == port->dev.parent;
722 }
723 
724 int cxl_num_decoders_committed(struct cxl_port *port);
725 bool is_cxl_port(const struct device *dev);
726 struct cxl_port *to_cxl_port(const struct device *dev);
727 struct cxl_port *parent_port_of(struct cxl_port *port);
728 void cxl_port_commit_reap(struct cxl_decoder *cxld);
729 struct pci_bus;
730 int devm_cxl_register_pci_bus(struct device *host, struct device *uport_dev,
731 			      struct pci_bus *bus);
732 struct pci_bus *cxl_port_to_pci_bus(struct cxl_port *port);
733 struct cxl_port *devm_cxl_add_port(struct device *host,
734 				   struct device *uport_dev,
735 				   resource_size_t component_reg_phys,
736 				   struct cxl_dport *parent_dport);
737 struct cxl_root *devm_cxl_add_root(struct device *host,
738 				   const struct cxl_root_ops *ops);
739 struct cxl_root *find_cxl_root(struct cxl_port *port);
740 
741 DEFINE_FREE(put_cxl_root, struct cxl_root *, if (_T) put_device(&_T->port.dev))
742 DEFINE_FREE(put_cxl_port, struct cxl_port *, if (!IS_ERR_OR_NULL(_T)) put_device(&_T->dev))
743 DEFINE_FREE(put_cxl_root_decoder, struct cxl_root_decoder *, if (!IS_ERR_OR_NULL(_T)) put_device(&_T->cxlsd.cxld.dev))
744 DEFINE_FREE(put_cxl_region, struct cxl_region *, if (!IS_ERR_OR_NULL(_T)) put_device(&_T->dev))
745 
746 int devm_cxl_enumerate_ports(struct cxl_memdev *cxlmd);
747 void cxl_bus_rescan(void);
748 void cxl_bus_drain(void);
749 struct cxl_port *cxl_pci_find_port(struct pci_dev *pdev,
750 				   struct cxl_dport **dport);
751 struct cxl_port *cxl_mem_find_port(struct cxl_memdev *cxlmd,
752 				   struct cxl_dport **dport);
753 bool schedule_cxl_memdev_detach(struct cxl_memdev *cxlmd);
754 
755 struct cxl_dport *devm_cxl_add_dport(struct cxl_port *port,
756 				     struct device *dport, int port_id,
757 				     resource_size_t component_reg_phys);
758 struct cxl_dport *devm_cxl_add_rch_dport(struct cxl_port *port,
759 					 struct device *dport_dev, int port_id,
760 					 resource_size_t rcrb);
761 
762 #ifdef CONFIG_PCIEAER_CXL
763 void cxl_setup_parent_dport(struct device *host, struct cxl_dport *dport);
764 void cxl_dport_init_ras_reporting(struct cxl_dport *dport, struct device *host);
765 #else
766 static inline void cxl_dport_init_ras_reporting(struct cxl_dport *dport,
767 						struct device *host) { }
768 #endif
769 
770 struct cxl_decoder *to_cxl_decoder(struct device *dev);
771 struct cxl_root_decoder *to_cxl_root_decoder(struct device *dev);
772 struct cxl_switch_decoder *to_cxl_switch_decoder(struct device *dev);
773 struct cxl_endpoint_decoder *to_cxl_endpoint_decoder(struct device *dev);
774 bool is_root_decoder(struct device *dev);
775 bool is_switch_decoder(struct device *dev);
776 bool is_endpoint_decoder(struct device *dev);
777 struct cxl_root_decoder *cxl_root_decoder_alloc(struct cxl_port *port,
778 						unsigned int nr_targets);
779 struct cxl_switch_decoder *cxl_switch_decoder_alloc(struct cxl_port *port,
780 						    unsigned int nr_targets);
781 int cxl_decoder_add(struct cxl_decoder *cxld, int *target_map);
782 struct cxl_endpoint_decoder *cxl_endpoint_decoder_alloc(struct cxl_port *port);
783 int cxl_decoder_add_locked(struct cxl_decoder *cxld, int *target_map);
784 int cxl_decoder_autoremove(struct device *host, struct cxl_decoder *cxld);
785 static inline int cxl_root_decoder_autoremove(struct device *host,
786 					      struct cxl_root_decoder *cxlrd)
787 {
788 	return cxl_decoder_autoremove(host, &cxlrd->cxlsd.cxld);
789 }
790 int cxl_endpoint_autoremove(struct cxl_memdev *cxlmd, struct cxl_port *endpoint);
791 
792 /**
793  * struct cxl_endpoint_dvsec_info - Cached DVSEC info
794  * @mem_enabled: cached value of mem_enabled in the DVSEC at init time
795  * @ranges: Number of active HDM ranges this device uses.
796  * @port: endpoint port associated with this info instance
797  * @dvsec_range: cached attributes of the ranges in the DVSEC, PCIE_DEVICE
798  */
799 struct cxl_endpoint_dvsec_info {
800 	bool mem_enabled;
801 	int ranges;
802 	struct cxl_port *port;
803 	struct range dvsec_range[2];
804 };
805 
806 struct cxl_hdm;
807 struct cxl_hdm *devm_cxl_setup_hdm(struct cxl_port *port,
808 				   struct cxl_endpoint_dvsec_info *info);
809 int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm,
810 				struct cxl_endpoint_dvsec_info *info);
811 int devm_cxl_add_passthrough_decoder(struct cxl_port *port);
812 struct cxl_dev_state;
813 int cxl_dvsec_rr_decode(struct cxl_dev_state *cxlds,
814 			struct cxl_endpoint_dvsec_info *info);
815 
816 bool is_cxl_region(struct device *dev);
817 
818 extern struct bus_type cxl_bus_type;
819 
820 struct cxl_driver {
821 	const char *name;
822 	int (*probe)(struct device *dev);
823 	void (*remove)(struct device *dev);
824 	struct device_driver drv;
825 	int id;
826 };
827 
828 #define to_cxl_drv(__drv)	container_of_const(__drv, struct cxl_driver, drv)
829 
830 int __cxl_driver_register(struct cxl_driver *cxl_drv, struct module *owner,
831 			  const char *modname);
832 #define cxl_driver_register(x) __cxl_driver_register(x, THIS_MODULE, KBUILD_MODNAME)
833 void cxl_driver_unregister(struct cxl_driver *cxl_drv);
834 
835 #define module_cxl_driver(__cxl_driver) \
836 	module_driver(__cxl_driver, cxl_driver_register, cxl_driver_unregister)
837 
838 #define CXL_DEVICE_NVDIMM_BRIDGE	1
839 #define CXL_DEVICE_NVDIMM		2
840 #define CXL_DEVICE_PORT			3
841 #define CXL_DEVICE_ROOT			4
842 #define CXL_DEVICE_MEMORY_EXPANDER	5
843 #define CXL_DEVICE_REGION		6
844 #define CXL_DEVICE_PMEM_REGION		7
845 #define CXL_DEVICE_DAX_REGION		8
846 #define CXL_DEVICE_PMU			9
847 
848 #define MODULE_ALIAS_CXL(type) MODULE_ALIAS("cxl:t" __stringify(type) "*")
849 #define CXL_MODALIAS_FMT "cxl:t%d"
850 
851 struct cxl_nvdimm_bridge *to_cxl_nvdimm_bridge(struct device *dev);
852 struct cxl_nvdimm_bridge *devm_cxl_add_nvdimm_bridge(struct device *host,
853 						     struct cxl_port *port);
854 struct cxl_nvdimm *to_cxl_nvdimm(struct device *dev);
855 bool is_cxl_nvdimm(struct device *dev);
856 int devm_cxl_add_nvdimm(struct cxl_port *parent_port, struct cxl_memdev *cxlmd);
857 struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_port *port);
858 
859 #ifdef CONFIG_CXL_REGION
860 bool is_cxl_pmem_region(struct device *dev);
861 struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev);
862 int cxl_add_to_region(struct cxl_endpoint_decoder *cxled);
863 struct cxl_dax_region *to_cxl_dax_region(struct device *dev);
864 u64 cxl_port_get_spa_cache_alias(struct cxl_port *endpoint, u64 spa);
865 #else
866 static inline bool is_cxl_pmem_region(struct device *dev)
867 {
868 	return false;
869 }
870 static inline struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev)
871 {
872 	return NULL;
873 }
874 static inline int cxl_add_to_region(struct cxl_endpoint_decoder *cxled)
875 {
876 	return 0;
877 }
878 static inline struct cxl_dax_region *to_cxl_dax_region(struct device *dev)
879 {
880 	return NULL;
881 }
882 static inline u64 cxl_port_get_spa_cache_alias(struct cxl_port *endpoint,
883 					       u64 spa)
884 {
885 	return 0;
886 }
887 #endif
888 
889 void cxl_endpoint_parse_cdat(struct cxl_port *port);
890 void cxl_switch_parse_cdat(struct cxl_port *port);
891 
892 int cxl_endpoint_get_perf_coordinates(struct cxl_port *port,
893 				      struct access_coordinate *coord);
894 void cxl_region_perf_data_calculate(struct cxl_region *cxlr,
895 				    struct cxl_endpoint_decoder *cxled);
896 void cxl_region_shared_upstream_bandwidth_update(struct cxl_region *cxlr);
897 
898 void cxl_memdev_update_perf(struct cxl_memdev *cxlmd);
899 
900 void cxl_coordinates_combine(struct access_coordinate *out,
901 			     struct access_coordinate *c1,
902 			     struct access_coordinate *c2);
903 
904 bool cxl_endpoint_decoder_reset_detected(struct cxl_port *port);
905 
906 /*
907  * Unit test builds overrides this to __weak, find the 'strong' version
908  * of these symbols in tools/testing/cxl/.
909  */
910 #ifndef __mock
911 #define __mock static
912 #endif
913 
914 u16 cxl_gpf_get_dvsec(struct device *dev);
915 
916 static inline struct rw_semaphore *rwsem_read_intr_acquire(struct rw_semaphore *rwsem)
917 {
918 	if (down_read_interruptible(rwsem))
919 		return NULL;
920 
921 	return rwsem;
922 }
923 
924 DEFINE_FREE(rwsem_read_release, struct rw_semaphore *, if (_T) up_read(_T))
925 
926 #endif /* __CXL_H__ */
927