xref: /linux/drivers/cxl/cxl.h (revision db1ecca22edf27c5a3dd66af406c88b5b5ac7cc1)
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_HOSTONLY 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_CAP_BG_CMD_IRQ BIT(6)
180 #define   CXLDEV_MBOX_CAP_IRQ_MSGNUM_MASK GENMASK(10, 7)
181 #define CXLDEV_MBOX_CTRL_OFFSET 0x04
182 #define   CXLDEV_MBOX_CTRL_DOORBELL BIT(0)
183 #define   CXLDEV_MBOX_CTRL_BG_CMD_IRQ BIT(2)
184 #define CXLDEV_MBOX_CMD_OFFSET 0x08
185 #define   CXLDEV_MBOX_CMD_COMMAND_OPCODE_MASK GENMASK_ULL(15, 0)
186 #define   CXLDEV_MBOX_CMD_PAYLOAD_LENGTH_MASK GENMASK_ULL(36, 16)
187 #define CXLDEV_MBOX_STATUS_OFFSET 0x10
188 #define   CXLDEV_MBOX_STATUS_BG_CMD BIT(0)
189 #define   CXLDEV_MBOX_STATUS_RET_CODE_MASK GENMASK_ULL(47, 32)
190 #define CXLDEV_MBOX_BG_CMD_STATUS_OFFSET 0x18
191 #define   CXLDEV_MBOX_BG_CMD_COMMAND_OPCODE_MASK GENMASK_ULL(15, 0)
192 #define   CXLDEV_MBOX_BG_CMD_COMMAND_PCT_MASK GENMASK_ULL(22, 16)
193 #define   CXLDEV_MBOX_BG_CMD_COMMAND_RC_MASK GENMASK_ULL(47, 32)
194 #define   CXLDEV_MBOX_BG_CMD_COMMAND_VENDOR_MASK GENMASK_ULL(63, 48)
195 #define CXLDEV_MBOX_PAYLOAD_OFFSET 0x20
196 
197 /*
198  * Using struct_group() allows for per register-block-type helper routines,
199  * without requiring block-type agnostic code to include the prefix.
200  */
201 struct cxl_regs {
202 	/*
203 	 * Common set of CXL Component register block base pointers
204 	 * @hdm_decoder: CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure
205 	 * @ras: CXL 2.0 8.2.5.9 CXL RAS Capability Structure
206 	 */
207 	struct_group_tagged(cxl_component_regs, component,
208 		void __iomem *hdm_decoder;
209 		void __iomem *ras;
210 	);
211 	/*
212 	 * Common set of CXL Device register block base pointers
213 	 * @status: CXL 2.0 8.2.8.3 Device Status Registers
214 	 * @mbox: CXL 2.0 8.2.8.4 Mailbox Registers
215 	 * @memdev: CXL 2.0 8.2.8.5 Memory Device Registers
216 	 */
217 	struct_group_tagged(cxl_device_regs, device_regs,
218 		void __iomem *status, *mbox, *memdev;
219 	);
220 
221 	struct_group_tagged(cxl_pmu_regs, pmu_regs,
222 		void __iomem *pmu;
223 	);
224 
225 	/*
226 	 * RCH downstream port specific RAS register
227 	 * @aer: CXL 3.0 8.2.1.1 RCH Downstream Port RCRB
228 	 */
229 	struct_group_tagged(cxl_rch_regs, rch_regs,
230 		void __iomem *dport_aer;
231 	);
232 };
233 
234 struct cxl_reg_map {
235 	bool valid;
236 	int id;
237 	unsigned long offset;
238 	unsigned long size;
239 };
240 
241 struct cxl_component_reg_map {
242 	struct cxl_reg_map hdm_decoder;
243 	struct cxl_reg_map ras;
244 };
245 
246 struct cxl_device_reg_map {
247 	struct cxl_reg_map status;
248 	struct cxl_reg_map mbox;
249 	struct cxl_reg_map memdev;
250 };
251 
252 struct cxl_pmu_reg_map {
253 	struct cxl_reg_map pmu;
254 };
255 
256 /**
257  * struct cxl_register_map - DVSEC harvested register block mapping parameters
258  * @host: device for devm operations and logging
259  * @base: virtual base of the register-block-BAR + @block_offset
260  * @resource: physical resource base of the register block
261  * @max_size: maximum mapping size to perform register search
262  * @reg_type: see enum cxl_regloc_type
263  * @component_map: cxl_reg_map for component registers
264  * @device_map: cxl_reg_maps for device registers
265  * @pmu_map: cxl_reg_maps for CXL Performance Monitoring Units
266  */
267 struct cxl_register_map {
268 	struct device *host;
269 	void __iomem *base;
270 	resource_size_t resource;
271 	resource_size_t max_size;
272 	u8 reg_type;
273 	union {
274 		struct cxl_component_reg_map component_map;
275 		struct cxl_device_reg_map device_map;
276 		struct cxl_pmu_reg_map pmu_map;
277 	};
278 };
279 
280 void cxl_probe_component_regs(struct device *dev, void __iomem *base,
281 			      struct cxl_component_reg_map *map);
282 void cxl_probe_device_regs(struct device *dev, void __iomem *base,
283 			   struct cxl_device_reg_map *map);
284 int cxl_map_component_regs(const struct cxl_register_map *map,
285 			   struct cxl_component_regs *regs,
286 			   unsigned long map_mask);
287 int cxl_map_device_regs(const struct cxl_register_map *map,
288 			struct cxl_device_regs *regs);
289 int cxl_map_pmu_regs(struct cxl_register_map *map, struct cxl_pmu_regs *regs);
290 
291 enum cxl_regloc_type;
292 int cxl_count_regblock(struct pci_dev *pdev, enum cxl_regloc_type type);
293 int cxl_find_regblock_instance(struct pci_dev *pdev, enum cxl_regloc_type type,
294 			       struct cxl_register_map *map, int index);
295 int cxl_find_regblock(struct pci_dev *pdev, enum cxl_regloc_type type,
296 		      struct cxl_register_map *map);
297 int cxl_setup_regs(struct cxl_register_map *map);
298 struct cxl_dport;
299 resource_size_t cxl_rcd_component_reg_phys(struct device *dev,
300 					   struct cxl_dport *dport);
301 
302 #define CXL_RESOURCE_NONE ((resource_size_t) -1)
303 #define CXL_TARGET_STRLEN 20
304 
305 /*
306  * cxl_decoder flags that define the type of memory / devices this
307  * decoder supports as well as configuration lock status See "CXL 2.0
308  * 8.2.5.12.7 CXL HDM Decoder 0 Control Register" for details.
309  * Additionally indicate whether decoder settings were autodetected,
310  * user customized.
311  */
312 #define CXL_DECODER_F_RAM   BIT(0)
313 #define CXL_DECODER_F_PMEM  BIT(1)
314 #define CXL_DECODER_F_TYPE2 BIT(2)
315 #define CXL_DECODER_F_TYPE3 BIT(3)
316 #define CXL_DECODER_F_LOCK  BIT(4)
317 #define CXL_DECODER_F_ENABLE    BIT(5)
318 #define CXL_DECODER_F_MASK  GENMASK(5, 0)
319 
320 enum cxl_decoder_type {
321 	CXL_DECODER_DEVMEM = 2,
322 	CXL_DECODER_HOSTONLYMEM = 3,
323 };
324 
325 /*
326  * Current specification goes up to 8, double that seems a reasonable
327  * software max for the foreseeable future
328  */
329 #define CXL_DECODER_MAX_INTERLEAVE 16
330 
331 #define CXL_QOS_CLASS_INVALID -1
332 
333 /**
334  * struct cxl_decoder - Common CXL HDM Decoder Attributes
335  * @dev: this decoder's device
336  * @id: kernel device name id
337  * @hpa_range: Host physical address range mapped by this decoder
338  * @interleave_ways: number of cxl_dports in this decode
339  * @interleave_granularity: data stride per dport
340  * @target_type: accelerator vs expander (type2 vs type3) selector
341  * @region: currently assigned region for this decoder
342  * @flags: memory type capabilities and locking
343  * @commit: device/decoder-type specific callback to commit settings to hw
344  * @reset: device/decoder-type specific callback to reset hw settings
345 */
346 struct cxl_decoder {
347 	struct device dev;
348 	int id;
349 	struct range hpa_range;
350 	int interleave_ways;
351 	int interleave_granularity;
352 	enum cxl_decoder_type target_type;
353 	struct cxl_region *region;
354 	unsigned long flags;
355 	int (*commit)(struct cxl_decoder *cxld);
356 	int (*reset)(struct cxl_decoder *cxld);
357 };
358 
359 /*
360  * CXL_DECODER_DEAD prevents endpoints from being reattached to regions
361  * while cxld_unregister() is running
362  */
363 enum cxl_decoder_mode {
364 	CXL_DECODER_NONE,
365 	CXL_DECODER_RAM,
366 	CXL_DECODER_PMEM,
367 	CXL_DECODER_MIXED,
368 	CXL_DECODER_DEAD,
369 };
370 
371 static inline const char *cxl_decoder_mode_name(enum cxl_decoder_mode mode)
372 {
373 	static const char * const names[] = {
374 		[CXL_DECODER_NONE] = "none",
375 		[CXL_DECODER_RAM] = "ram",
376 		[CXL_DECODER_PMEM] = "pmem",
377 		[CXL_DECODER_MIXED] = "mixed",
378 	};
379 
380 	if (mode >= CXL_DECODER_NONE && mode <= CXL_DECODER_MIXED)
381 		return names[mode];
382 	return "mixed";
383 }
384 
385 /*
386  * Track whether this decoder is reserved for region autodiscovery, or
387  * free for userspace provisioning.
388  */
389 enum cxl_decoder_state {
390 	CXL_DECODER_STATE_MANUAL,
391 	CXL_DECODER_STATE_AUTO,
392 };
393 
394 /**
395  * struct cxl_endpoint_decoder - Endpoint  / SPA to DPA decoder
396  * @cxld: base cxl_decoder_object
397  * @dpa_res: actively claimed DPA span of this decoder
398  * @skip: offset into @dpa_res where @cxld.hpa_range maps
399  * @mode: which memory type / access-mode-partition this decoder targets
400  * @state: autodiscovery state
401  * @pos: interleave position in @cxld.region
402  */
403 struct cxl_endpoint_decoder {
404 	struct cxl_decoder cxld;
405 	struct resource *dpa_res;
406 	resource_size_t skip;
407 	enum cxl_decoder_mode mode;
408 	enum cxl_decoder_state state;
409 	int pos;
410 };
411 
412 /**
413  * struct cxl_switch_decoder - Switch specific CXL HDM Decoder
414  * @cxld: base cxl_decoder object
415  * @target_lock: coordinate coherent reads of the target list
416  * @nr_targets: number of elements in @target
417  * @target: active ordered target list in current decoder configuration
418  *
419  * The 'switch' decoder type represents the decoder instances of cxl_port's that
420  * route from the root of a CXL memory decode topology to the endpoints. They
421  * come in two flavors, root-level decoders, statically defined by platform
422  * firmware, and mid-level decoders, where interleave-granularity,
423  * interleave-width, and the target list are mutable.
424  */
425 struct cxl_switch_decoder {
426 	struct cxl_decoder cxld;
427 	seqlock_t target_lock;
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  */
522 struct cxl_region {
523 	struct device dev;
524 	int id;
525 	enum cxl_decoder_mode mode;
526 	enum cxl_decoder_type type;
527 	struct cxl_nvdimm_bridge *cxl_nvb;
528 	struct cxl_pmem_region *cxlr_pmem;
529 	unsigned long flags;
530 	struct cxl_region_params params;
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 };
548 
549 struct cxl_pmem_region_mapping {
550 	struct cxl_memdev *cxlmd;
551 	struct cxl_nvdimm *cxl_nvd;
552 	u64 start;
553 	u64 size;
554 	int position;
555 };
556 
557 struct cxl_pmem_region {
558 	struct device dev;
559 	struct cxl_region *cxlr;
560 	struct nd_region *nd_region;
561 	struct range hpa_range;
562 	int nr_mappings;
563 	struct cxl_pmem_region_mapping mapping[];
564 };
565 
566 struct cxl_dax_region {
567 	struct device dev;
568 	struct cxl_region *cxlr;
569 	struct range hpa_range;
570 };
571 
572 /**
573  * struct cxl_port - logical collection of upstream port devices and
574  *		     downstream port devices to construct a CXL memory
575  *		     decode hierarchy.
576  * @dev: this port's device
577  * @uport_dev: PCI or platform device implementing the upstream port capability
578  * @host_bridge: Shortcut to the platform attach point for this port
579  * @id: id for port device-name
580  * @dports: cxl_dport instances referenced by decoders
581  * @endpoints: cxl_ep instances, endpoints that are a descendant of this port
582  * @regions: cxl_region_ref instances, regions mapped by this port
583  * @parent_dport: dport that points to this port in the parent
584  * @decoder_ida: allocator for decoder ids
585  * @reg_map: component and ras register mapping parameters
586  * @nr_dports: number of entries in @dports
587  * @hdm_end: track last allocated HDM decoder instance for allocation ordering
588  * @commit_end: cursor to track highest committed decoder for commit ordering
589  * @dead: last ep has been removed, force port re-creation
590  * @depth: How deep this port is relative to the root. depth 0 is the root.
591  * @cdat: Cached CDAT data
592  * @cdat_available: Should a CDAT attribute be available in sysfs
593  */
594 struct cxl_port {
595 	struct device dev;
596 	struct device *uport_dev;
597 	struct device *host_bridge;
598 	int id;
599 	struct xarray dports;
600 	struct xarray endpoints;
601 	struct xarray regions;
602 	struct cxl_dport *parent_dport;
603 	struct ida decoder_ida;
604 	struct cxl_register_map reg_map;
605 	int nr_dports;
606 	int hdm_end;
607 	int commit_end;
608 	bool dead;
609 	unsigned int depth;
610 	struct cxl_cdat {
611 		void *table;
612 		size_t length;
613 	} cdat;
614 	bool cdat_available;
615 };
616 
617 static inline struct cxl_dport *
618 cxl_find_dport_by_dev(struct cxl_port *port, const struct device *dport_dev)
619 {
620 	return xa_load(&port->dports, (unsigned long)dport_dev);
621 }
622 
623 struct cxl_rcrb_info {
624 	resource_size_t base;
625 	u16 aer_cap;
626 };
627 
628 /**
629  * struct cxl_dport - CXL downstream port
630  * @dport_dev: PCI bridge or firmware device representing the downstream link
631  * @reg_map: component and ras register mapping parameters
632  * @port_id: unique hardware identifier for dport in decoder target list
633  * @rcrb: Data about the Root Complex Register Block layout
634  * @rch: Indicate whether this dport was enumerated in RCH or VH mode
635  * @port: reference to cxl_port that contains this downstream port
636  * @regs: Dport parsed register blocks
637  */
638 struct cxl_dport {
639 	struct device *dport_dev;
640 	struct cxl_register_map reg_map;
641 	int port_id;
642 	struct cxl_rcrb_info rcrb;
643 	bool rch;
644 	struct cxl_port *port;
645 	struct cxl_regs regs;
646 };
647 
648 /**
649  * struct cxl_ep - track an endpoint's interest in a port
650  * @ep: device that hosts a generic CXL endpoint (expander or accelerator)
651  * @dport: which dport routes to this endpoint on @port
652  * @next: cxl switch port across the link attached to @dport NULL if
653  *	  attached to an endpoint
654  */
655 struct cxl_ep {
656 	struct device *ep;
657 	struct cxl_dport *dport;
658 	struct cxl_port *next;
659 };
660 
661 /**
662  * struct cxl_region_ref - track a region's interest in a port
663  * @port: point in topology to install this reference
664  * @decoder: decoder assigned for @region in @port
665  * @region: region for this reference
666  * @endpoints: cxl_ep references for region members beneath @port
667  * @nr_targets_set: track how many targets have been programmed during setup
668  * @nr_eps: number of endpoints beneath @port
669  * @nr_targets: number of distinct targets needed to reach @nr_eps
670  */
671 struct cxl_region_ref {
672 	struct cxl_port *port;
673 	struct cxl_decoder *decoder;
674 	struct cxl_region *region;
675 	struct xarray endpoints;
676 	int nr_targets_set;
677 	int nr_eps;
678 	int nr_targets;
679 };
680 
681 /*
682  * The platform firmware device hosting the root is also the top of the
683  * CXL port topology. All other CXL ports have another CXL port as their
684  * parent and their ->uport_dev / host device is out-of-line of the port
685  * ancestry.
686  */
687 static inline bool is_cxl_root(struct cxl_port *port)
688 {
689 	return port->uport_dev == port->dev.parent;
690 }
691 
692 int cxl_num_decoders_committed(struct cxl_port *port);
693 bool is_cxl_port(const struct device *dev);
694 struct cxl_port *to_cxl_port(const struct device *dev);
695 struct pci_bus;
696 int devm_cxl_register_pci_bus(struct device *host, struct device *uport_dev,
697 			      struct pci_bus *bus);
698 struct pci_bus *cxl_port_to_pci_bus(struct cxl_port *port);
699 struct cxl_port *devm_cxl_add_port(struct device *host,
700 				   struct device *uport_dev,
701 				   resource_size_t component_reg_phys,
702 				   struct cxl_dport *parent_dport);
703 struct cxl_port *find_cxl_root(struct cxl_port *port);
704 int devm_cxl_enumerate_ports(struct cxl_memdev *cxlmd);
705 void cxl_bus_rescan(void);
706 void cxl_bus_drain(void);
707 struct cxl_port *cxl_pci_find_port(struct pci_dev *pdev,
708 				   struct cxl_dport **dport);
709 struct cxl_port *cxl_mem_find_port(struct cxl_memdev *cxlmd,
710 				   struct cxl_dport **dport);
711 bool schedule_cxl_memdev_detach(struct cxl_memdev *cxlmd);
712 
713 struct cxl_dport *devm_cxl_add_dport(struct cxl_port *port,
714 				     struct device *dport, int port_id,
715 				     resource_size_t component_reg_phys);
716 struct cxl_dport *devm_cxl_add_rch_dport(struct cxl_port *port,
717 					 struct device *dport_dev, int port_id,
718 					 resource_size_t rcrb);
719 
720 #ifdef CONFIG_PCIEAER_CXL
721 void cxl_setup_parent_dport(struct device *host, struct cxl_dport *dport);
722 #else
723 static inline void cxl_setup_parent_dport(struct device *host,
724 					  struct cxl_dport *dport) { }
725 #endif
726 
727 struct cxl_decoder *to_cxl_decoder(struct device *dev);
728 struct cxl_root_decoder *to_cxl_root_decoder(struct device *dev);
729 struct cxl_switch_decoder *to_cxl_switch_decoder(struct device *dev);
730 struct cxl_endpoint_decoder *to_cxl_endpoint_decoder(struct device *dev);
731 bool is_root_decoder(struct device *dev);
732 bool is_switch_decoder(struct device *dev);
733 bool is_endpoint_decoder(struct device *dev);
734 struct cxl_root_decoder *cxl_root_decoder_alloc(struct cxl_port *port,
735 						unsigned int nr_targets,
736 						cxl_calc_hb_fn calc_hb);
737 struct cxl_dport *cxl_hb_modulo(struct cxl_root_decoder *cxlrd, int pos);
738 struct cxl_switch_decoder *cxl_switch_decoder_alloc(struct cxl_port *port,
739 						    unsigned int nr_targets);
740 int cxl_decoder_add(struct cxl_decoder *cxld, int *target_map);
741 struct cxl_endpoint_decoder *cxl_endpoint_decoder_alloc(struct cxl_port *port);
742 int cxl_decoder_add_locked(struct cxl_decoder *cxld, int *target_map);
743 int cxl_decoder_autoremove(struct device *host, struct cxl_decoder *cxld);
744 int cxl_endpoint_autoremove(struct cxl_memdev *cxlmd, struct cxl_port *endpoint);
745 
746 /**
747  * struct cxl_endpoint_dvsec_info - Cached DVSEC info
748  * @mem_enabled: cached value of mem_enabled in the DVSEC at init time
749  * @ranges: Number of active HDM ranges this device uses.
750  * @port: endpoint port associated with this info instance
751  * @dvsec_range: cached attributes of the ranges in the DVSEC, PCIE_DEVICE
752  */
753 struct cxl_endpoint_dvsec_info {
754 	bool mem_enabled;
755 	int ranges;
756 	struct cxl_port *port;
757 	struct range dvsec_range[2];
758 };
759 
760 struct cxl_hdm;
761 struct cxl_hdm *devm_cxl_setup_hdm(struct cxl_port *port,
762 				   struct cxl_endpoint_dvsec_info *info);
763 int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm,
764 				struct cxl_endpoint_dvsec_info *info);
765 int devm_cxl_add_passthrough_decoder(struct cxl_port *port);
766 int cxl_dvsec_rr_decode(struct device *dev, int dvsec,
767 			struct cxl_endpoint_dvsec_info *info);
768 
769 bool is_cxl_region(struct device *dev);
770 
771 extern struct bus_type cxl_bus_type;
772 
773 struct cxl_driver {
774 	const char *name;
775 	int (*probe)(struct device *dev);
776 	void (*remove)(struct device *dev);
777 	struct device_driver drv;
778 	int id;
779 };
780 
781 static inline struct cxl_driver *to_cxl_drv(struct device_driver *drv)
782 {
783 	return container_of(drv, struct cxl_driver, drv);
784 }
785 
786 int __cxl_driver_register(struct cxl_driver *cxl_drv, struct module *owner,
787 			  const char *modname);
788 #define cxl_driver_register(x) __cxl_driver_register(x, THIS_MODULE, KBUILD_MODNAME)
789 void cxl_driver_unregister(struct cxl_driver *cxl_drv);
790 
791 #define module_cxl_driver(__cxl_driver) \
792 	module_driver(__cxl_driver, cxl_driver_register, cxl_driver_unregister)
793 
794 #define CXL_DEVICE_NVDIMM_BRIDGE	1
795 #define CXL_DEVICE_NVDIMM		2
796 #define CXL_DEVICE_PORT			3
797 #define CXL_DEVICE_ROOT			4
798 #define CXL_DEVICE_MEMORY_EXPANDER	5
799 #define CXL_DEVICE_REGION		6
800 #define CXL_DEVICE_PMEM_REGION		7
801 #define CXL_DEVICE_DAX_REGION		8
802 #define CXL_DEVICE_PMU			9
803 
804 #define MODULE_ALIAS_CXL(type) MODULE_ALIAS("cxl:t" __stringify(type) "*")
805 #define CXL_MODALIAS_FMT "cxl:t%d"
806 
807 struct cxl_nvdimm_bridge *to_cxl_nvdimm_bridge(struct device *dev);
808 struct cxl_nvdimm_bridge *devm_cxl_add_nvdimm_bridge(struct device *host,
809 						     struct cxl_port *port);
810 struct cxl_nvdimm *to_cxl_nvdimm(struct device *dev);
811 bool is_cxl_nvdimm(struct device *dev);
812 bool is_cxl_nvdimm_bridge(struct device *dev);
813 int devm_cxl_add_nvdimm(struct cxl_memdev *cxlmd);
814 struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_memdev *cxlmd);
815 
816 #ifdef CONFIG_CXL_REGION
817 bool is_cxl_pmem_region(struct device *dev);
818 struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev);
819 int cxl_add_to_region(struct cxl_port *root,
820 		      struct cxl_endpoint_decoder *cxled);
821 struct cxl_dax_region *to_cxl_dax_region(struct device *dev);
822 #else
823 static inline bool is_cxl_pmem_region(struct device *dev)
824 {
825 	return false;
826 }
827 static inline struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev)
828 {
829 	return NULL;
830 }
831 static inline int cxl_add_to_region(struct cxl_port *root,
832 				    struct cxl_endpoint_decoder *cxled)
833 {
834 	return 0;
835 }
836 static inline struct cxl_dax_region *to_cxl_dax_region(struct device *dev)
837 {
838 	return NULL;
839 }
840 #endif
841 
842 /*
843  * Unit test builds overrides this to __weak, find the 'strong' version
844  * of these symbols in tools/testing/cxl/.
845  */
846 #ifndef __mock
847 #define __mock static
848 #endif
849 
850 #endif /* __CXL_H__ */
851