xref: /openbmc/linux/drivers/cxl/cxl.h (revision 98a52692)
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 struct cxl_reg_map {
227 	bool valid;
228 	int id;
229 	unsigned long offset;
230 	unsigned long size;
231 };
232 
233 struct cxl_component_reg_map {
234 	struct cxl_reg_map hdm_decoder;
235 	struct cxl_reg_map ras;
236 };
237 
238 struct cxl_device_reg_map {
239 	struct cxl_reg_map status;
240 	struct cxl_reg_map mbox;
241 	struct cxl_reg_map memdev;
242 };
243 
244 struct cxl_pmu_reg_map {
245 	struct cxl_reg_map pmu;
246 };
247 
248 /**
249  * struct cxl_register_map - DVSEC harvested register block mapping parameters
250  * @host: device for devm operations and logging
251  * @base: virtual base of the register-block-BAR + @block_offset
252  * @resource: physical resource base of the register block
253  * @max_size: maximum mapping size to perform register search
254  * @reg_type: see enum cxl_regloc_type
255  * @component_map: cxl_reg_map for component registers
256  * @device_map: cxl_reg_maps for device registers
257  * @pmu_map: cxl_reg_maps for CXL Performance Monitoring Units
258  */
259 struct cxl_register_map {
260 	struct device *host;
261 	void __iomem *base;
262 	resource_size_t resource;
263 	resource_size_t max_size;
264 	u8 reg_type;
265 	union {
266 		struct cxl_component_reg_map component_map;
267 		struct cxl_device_reg_map device_map;
268 		struct cxl_pmu_reg_map pmu_map;
269 	};
270 };
271 
272 void cxl_probe_component_regs(struct device *dev, void __iomem *base,
273 			      struct cxl_component_reg_map *map);
274 void cxl_probe_device_regs(struct device *dev, void __iomem *base,
275 			   struct cxl_device_reg_map *map);
276 int cxl_map_component_regs(const struct cxl_register_map *map,
277 			   struct cxl_component_regs *regs,
278 			   unsigned long map_mask);
279 int cxl_map_device_regs(const struct cxl_register_map *map,
280 			struct cxl_device_regs *regs);
281 int cxl_map_pmu_regs(struct pci_dev *pdev, struct cxl_pmu_regs *regs,
282 		     struct cxl_register_map *map);
283 
284 enum cxl_regloc_type;
285 int cxl_count_regblock(struct pci_dev *pdev, enum cxl_regloc_type type);
286 int cxl_find_regblock_instance(struct pci_dev *pdev, enum cxl_regloc_type type,
287 			       struct cxl_register_map *map, int index);
288 int cxl_find_regblock(struct pci_dev *pdev, enum cxl_regloc_type type,
289 		      struct cxl_register_map *map);
290 int cxl_setup_regs(struct cxl_register_map *map);
291 struct cxl_dport;
292 resource_size_t cxl_rcd_component_reg_phys(struct device *dev,
293 					   struct cxl_dport *dport);
294 
295 #define CXL_RESOURCE_NONE ((resource_size_t) -1)
296 #define CXL_TARGET_STRLEN 20
297 
298 /*
299  * cxl_decoder flags that define the type of memory / devices this
300  * decoder supports as well as configuration lock status See "CXL 2.0
301  * 8.2.5.12.7 CXL HDM Decoder 0 Control Register" for details.
302  * Additionally indicate whether decoder settings were autodetected,
303  * user customized.
304  */
305 #define CXL_DECODER_F_RAM   BIT(0)
306 #define CXL_DECODER_F_PMEM  BIT(1)
307 #define CXL_DECODER_F_TYPE2 BIT(2)
308 #define CXL_DECODER_F_TYPE3 BIT(3)
309 #define CXL_DECODER_F_LOCK  BIT(4)
310 #define CXL_DECODER_F_ENABLE    BIT(5)
311 #define CXL_DECODER_F_MASK  GENMASK(5, 0)
312 
313 enum cxl_decoder_type {
314 	CXL_DECODER_DEVMEM = 2,
315 	CXL_DECODER_HOSTONLYMEM = 3,
316 };
317 
318 /*
319  * Current specification goes up to 8, double that seems a reasonable
320  * software max for the foreseeable future
321  */
322 #define CXL_DECODER_MAX_INTERLEAVE 16
323 
324 
325 /**
326  * struct cxl_decoder - Common CXL HDM Decoder Attributes
327  * @dev: this decoder's device
328  * @id: kernel device name id
329  * @hpa_range: Host physical address range mapped by this decoder
330  * @interleave_ways: number of cxl_dports in this decode
331  * @interleave_granularity: data stride per dport
332  * @target_type: accelerator vs expander (type2 vs type3) selector
333  * @region: currently assigned region for this decoder
334  * @flags: memory type capabilities and locking
335  * @commit: device/decoder-type specific callback to commit settings to hw
336  * @reset: device/decoder-type specific callback to reset hw settings
337 */
338 struct cxl_decoder {
339 	struct device dev;
340 	int id;
341 	struct range hpa_range;
342 	int interleave_ways;
343 	int interleave_granularity;
344 	enum cxl_decoder_type target_type;
345 	struct cxl_region *region;
346 	unsigned long flags;
347 	int (*commit)(struct cxl_decoder *cxld);
348 	int (*reset)(struct cxl_decoder *cxld);
349 };
350 
351 /*
352  * CXL_DECODER_DEAD prevents endpoints from being reattached to regions
353  * while cxld_unregister() is running
354  */
355 enum cxl_decoder_mode {
356 	CXL_DECODER_NONE,
357 	CXL_DECODER_RAM,
358 	CXL_DECODER_PMEM,
359 	CXL_DECODER_MIXED,
360 	CXL_DECODER_DEAD,
361 };
362 
363 static inline const char *cxl_decoder_mode_name(enum cxl_decoder_mode mode)
364 {
365 	static const char * const names[] = {
366 		[CXL_DECODER_NONE] = "none",
367 		[CXL_DECODER_RAM] = "ram",
368 		[CXL_DECODER_PMEM] = "pmem",
369 		[CXL_DECODER_MIXED] = "mixed",
370 	};
371 
372 	if (mode >= CXL_DECODER_NONE && mode <= CXL_DECODER_MIXED)
373 		return names[mode];
374 	return "mixed";
375 }
376 
377 /*
378  * Track whether this decoder is reserved for region autodiscovery, or
379  * free for userspace provisioning.
380  */
381 enum cxl_decoder_state {
382 	CXL_DECODER_STATE_MANUAL,
383 	CXL_DECODER_STATE_AUTO,
384 };
385 
386 /**
387  * struct cxl_endpoint_decoder - Endpoint  / SPA to DPA decoder
388  * @cxld: base cxl_decoder_object
389  * @dpa_res: actively claimed DPA span of this decoder
390  * @skip: offset into @dpa_res where @cxld.hpa_range maps
391  * @mode: which memory type / access-mode-partition this decoder targets
392  * @state: autodiscovery state
393  * @pos: interleave position in @cxld.region
394  */
395 struct cxl_endpoint_decoder {
396 	struct cxl_decoder cxld;
397 	struct resource *dpa_res;
398 	resource_size_t skip;
399 	enum cxl_decoder_mode mode;
400 	enum cxl_decoder_state state;
401 	int pos;
402 };
403 
404 /**
405  * struct cxl_switch_decoder - Switch specific CXL HDM Decoder
406  * @cxld: base cxl_decoder object
407  * @target_lock: coordinate coherent reads of the target list
408  * @nr_targets: number of elements in @target
409  * @target: active ordered target list in current decoder configuration
410  *
411  * The 'switch' decoder type represents the decoder instances of cxl_port's that
412  * route from the root of a CXL memory decode topology to the endpoints. They
413  * come in two flavors, root-level decoders, statically defined by platform
414  * firmware, and mid-level decoders, where interleave-granularity,
415  * interleave-width, and the target list are mutable.
416  */
417 struct cxl_switch_decoder {
418 	struct cxl_decoder cxld;
419 	seqlock_t target_lock;
420 	int nr_targets;
421 	struct cxl_dport *target[];
422 };
423 
424 struct cxl_root_decoder;
425 typedef struct cxl_dport *(*cxl_calc_hb_fn)(struct cxl_root_decoder *cxlrd,
426 					    int pos);
427 
428 /**
429  * struct cxl_root_decoder - Static platform CXL address decoder
430  * @res: host / parent resource for region allocations
431  * @region_id: region id for next region provisioning event
432  * @calc_hb: which host bridge covers the n'th position by granularity
433  * @platform_data: platform specific configuration data
434  * @range_lock: sync region autodiscovery by address range
435  * @cxlsd: base cxl switch decoder
436  */
437 struct cxl_root_decoder {
438 	struct resource *res;
439 	atomic_t region_id;
440 	cxl_calc_hb_fn calc_hb;
441 	void *platform_data;
442 	struct mutex range_lock;
443 	struct cxl_switch_decoder cxlsd;
444 };
445 
446 /*
447  * enum cxl_config_state - State machine for region configuration
448  * @CXL_CONFIG_IDLE: Any sysfs attribute can be written freely
449  * @CXL_CONFIG_INTERLEAVE_ACTIVE: region size has been set, no more
450  * changes to interleave_ways or interleave_granularity
451  * @CXL_CONFIG_ACTIVE: All targets have been added the region is now
452  * active
453  * @CXL_CONFIG_RESET_PENDING: see commit_store()
454  * @CXL_CONFIG_COMMIT: Soft-config has been committed to hardware
455  */
456 enum cxl_config_state {
457 	CXL_CONFIG_IDLE,
458 	CXL_CONFIG_INTERLEAVE_ACTIVE,
459 	CXL_CONFIG_ACTIVE,
460 	CXL_CONFIG_RESET_PENDING,
461 	CXL_CONFIG_COMMIT,
462 };
463 
464 /**
465  * struct cxl_region_params - region settings
466  * @state: allow the driver to lockdown further parameter changes
467  * @uuid: unique id for persistent regions
468  * @interleave_ways: number of endpoints in the region
469  * @interleave_granularity: capacity each endpoint contributes to a stripe
470  * @res: allocated iomem capacity for this region
471  * @targets: active ordered targets in current decoder configuration
472  * @nr_targets: number of targets
473  *
474  * State transitions are protected by the cxl_region_rwsem
475  */
476 struct cxl_region_params {
477 	enum cxl_config_state state;
478 	uuid_t uuid;
479 	int interleave_ways;
480 	int interleave_granularity;
481 	struct resource *res;
482 	struct cxl_endpoint_decoder *targets[CXL_DECODER_MAX_INTERLEAVE];
483 	int nr_targets;
484 };
485 
486 /*
487  * Indicate whether this region has been assembled by autodetection or
488  * userspace assembly. Prevent endpoint decoders outside of automatic
489  * detection from being added to the region.
490  */
491 #define CXL_REGION_F_AUTO 0
492 
493 /*
494  * Require that a committed region successfully complete a teardown once
495  * any of its associated decoders have been torn down. This maintains
496  * the commit state for the region since there are committed decoders,
497  * but blocks cxl_region_probe().
498  */
499 #define CXL_REGION_F_NEEDS_RESET 1
500 
501 /**
502  * struct cxl_region - CXL region
503  * @dev: This region's device
504  * @id: This region's id. Id is globally unique across all regions
505  * @mode: Endpoint decoder allocation / access mode
506  * @type: Endpoint decoder target type
507  * @cxl_nvb: nvdimm bridge for coordinating @cxlr_pmem setup / shutdown
508  * @cxlr_pmem: (for pmem regions) cached copy of the nvdimm bridge
509  * @flags: Region state flags
510  * @params: active + config params for the region
511  */
512 struct cxl_region {
513 	struct device dev;
514 	int id;
515 	enum cxl_decoder_mode mode;
516 	enum cxl_decoder_type type;
517 	struct cxl_nvdimm_bridge *cxl_nvb;
518 	struct cxl_pmem_region *cxlr_pmem;
519 	unsigned long flags;
520 	struct cxl_region_params params;
521 };
522 
523 struct cxl_nvdimm_bridge {
524 	int id;
525 	struct device dev;
526 	struct cxl_port *port;
527 	struct nvdimm_bus *nvdimm_bus;
528 	struct nvdimm_bus_descriptor nd_desc;
529 };
530 
531 #define CXL_DEV_ID_LEN 19
532 
533 struct cxl_nvdimm {
534 	struct device dev;
535 	struct cxl_memdev *cxlmd;
536 	u8 dev_id[CXL_DEV_ID_LEN]; /* for nvdimm, string of 'serial' */
537 };
538 
539 struct cxl_pmem_region_mapping {
540 	struct cxl_memdev *cxlmd;
541 	struct cxl_nvdimm *cxl_nvd;
542 	u64 start;
543 	u64 size;
544 	int position;
545 };
546 
547 struct cxl_pmem_region {
548 	struct device dev;
549 	struct cxl_region *cxlr;
550 	struct nd_region *nd_region;
551 	struct range hpa_range;
552 	int nr_mappings;
553 	struct cxl_pmem_region_mapping mapping[];
554 };
555 
556 struct cxl_dax_region {
557 	struct device dev;
558 	struct cxl_region *cxlr;
559 	struct range hpa_range;
560 };
561 
562 /**
563  * struct cxl_port - logical collection of upstream port devices and
564  *		     downstream port devices to construct a CXL memory
565  *		     decode hierarchy.
566  * @dev: this port's device
567  * @uport_dev: PCI or platform device implementing the upstream port capability
568  * @host_bridge: Shortcut to the platform attach point for this port
569  * @id: id for port device-name
570  * @dports: cxl_dport instances referenced by decoders
571  * @endpoints: cxl_ep instances, endpoints that are a descendant of this port
572  * @regions: cxl_region_ref instances, regions mapped by this port
573  * @parent_dport: dport that points to this port in the parent
574  * @decoder_ida: allocator for decoder ids
575  * @comp_map: component register capability mappings
576  * @nr_dports: number of entries in @dports
577  * @hdm_end: track last allocated HDM decoder instance for allocation ordering
578  * @commit_end: cursor to track highest committed decoder for commit ordering
579  * @component_reg_phys: component register capability base address (optional)
580  * @dead: last ep has been removed, force port re-creation
581  * @depth: How deep this port is relative to the root. depth 0 is the root.
582  * @cdat: Cached CDAT data
583  * @cdat_available: Should a CDAT attribute be available in sysfs
584  */
585 struct cxl_port {
586 	struct device dev;
587 	struct device *uport_dev;
588 	struct device *host_bridge;
589 	int id;
590 	struct xarray dports;
591 	struct xarray endpoints;
592 	struct xarray regions;
593 	struct cxl_dport *parent_dport;
594 	struct ida decoder_ida;
595 	struct cxl_register_map comp_map;
596 	int nr_dports;
597 	int hdm_end;
598 	int commit_end;
599 	resource_size_t component_reg_phys;
600 	bool dead;
601 	unsigned int depth;
602 	struct cxl_cdat {
603 		void *table;
604 		size_t length;
605 	} cdat;
606 	bool cdat_available;
607 };
608 
609 static inline struct cxl_dport *
610 cxl_find_dport_by_dev(struct cxl_port *port, const struct device *dport_dev)
611 {
612 	return xa_load(&port->dports, (unsigned long)dport_dev);
613 }
614 
615 struct cxl_rcrb_info {
616 	resource_size_t base;
617 	u16 aer_cap;
618 };
619 
620 /**
621  * struct cxl_dport - CXL downstream port
622  * @dport_dev: PCI bridge or firmware device representing the downstream link
623  * @comp_map: component register capability mappings
624  * @port_id: unique hardware identifier for dport in decoder target list
625  * @rcrb: Data about the Root Complex Register Block layout
626  * @rch: Indicate whether this dport was enumerated in RCH or VH mode
627  * @port: reference to cxl_port that contains this downstream port
628  */
629 struct cxl_dport {
630 	struct device *dport_dev;
631 	struct cxl_register_map comp_map;
632 	int port_id;
633 	struct cxl_rcrb_info rcrb;
634 	bool rch;
635 	struct cxl_port *port;
636 };
637 
638 /**
639  * struct cxl_ep - track an endpoint's interest in a port
640  * @ep: device that hosts a generic CXL endpoint (expander or accelerator)
641  * @dport: which dport routes to this endpoint on @port
642  * @next: cxl switch port across the link attached to @dport NULL if
643  *	  attached to an endpoint
644  */
645 struct cxl_ep {
646 	struct device *ep;
647 	struct cxl_dport *dport;
648 	struct cxl_port *next;
649 };
650 
651 /**
652  * struct cxl_region_ref - track a region's interest in a port
653  * @port: point in topology to install this reference
654  * @decoder: decoder assigned for @region in @port
655  * @region: region for this reference
656  * @endpoints: cxl_ep references for region members beneath @port
657  * @nr_targets_set: track how many targets have been programmed during setup
658  * @nr_eps: number of endpoints beneath @port
659  * @nr_targets: number of distinct targets needed to reach @nr_eps
660  */
661 struct cxl_region_ref {
662 	struct cxl_port *port;
663 	struct cxl_decoder *decoder;
664 	struct cxl_region *region;
665 	struct xarray endpoints;
666 	int nr_targets_set;
667 	int nr_eps;
668 	int nr_targets;
669 };
670 
671 /*
672  * The platform firmware device hosting the root is also the top of the
673  * CXL port topology. All other CXL ports have another CXL port as their
674  * parent and their ->uport_dev / host device is out-of-line of the port
675  * ancestry.
676  */
677 static inline bool is_cxl_root(struct cxl_port *port)
678 {
679 	return port->uport_dev == port->dev.parent;
680 }
681 
682 bool is_cxl_port(const struct device *dev);
683 struct cxl_port *to_cxl_port(const struct device *dev);
684 struct pci_bus;
685 int devm_cxl_register_pci_bus(struct device *host, struct device *uport_dev,
686 			      struct pci_bus *bus);
687 struct pci_bus *cxl_port_to_pci_bus(struct cxl_port *port);
688 struct cxl_port *devm_cxl_add_port(struct device *host,
689 				   struct device *uport_dev,
690 				   resource_size_t component_reg_phys,
691 				   struct cxl_dport *parent_dport);
692 struct cxl_port *find_cxl_root(struct cxl_port *port);
693 int devm_cxl_enumerate_ports(struct cxl_memdev *cxlmd);
694 void cxl_bus_rescan(void);
695 void cxl_bus_drain(void);
696 struct cxl_port *cxl_pci_find_port(struct pci_dev *pdev,
697 				   struct cxl_dport **dport);
698 struct cxl_port *cxl_mem_find_port(struct cxl_memdev *cxlmd,
699 				   struct cxl_dport **dport);
700 bool schedule_cxl_memdev_detach(struct cxl_memdev *cxlmd);
701 
702 struct cxl_dport *devm_cxl_add_dport(struct cxl_port *port,
703 				     struct device *dport, int port_id,
704 				     resource_size_t component_reg_phys);
705 struct cxl_dport *devm_cxl_add_rch_dport(struct cxl_port *port,
706 					 struct device *dport_dev, int port_id,
707 					 resource_size_t rcrb);
708 
709 struct cxl_decoder *to_cxl_decoder(struct device *dev);
710 struct cxl_root_decoder *to_cxl_root_decoder(struct device *dev);
711 struct cxl_switch_decoder *to_cxl_switch_decoder(struct device *dev);
712 struct cxl_endpoint_decoder *to_cxl_endpoint_decoder(struct device *dev);
713 bool is_root_decoder(struct device *dev);
714 bool is_switch_decoder(struct device *dev);
715 bool is_endpoint_decoder(struct device *dev);
716 struct cxl_root_decoder *cxl_root_decoder_alloc(struct cxl_port *port,
717 						unsigned int nr_targets,
718 						cxl_calc_hb_fn calc_hb);
719 struct cxl_dport *cxl_hb_modulo(struct cxl_root_decoder *cxlrd, int pos);
720 struct cxl_switch_decoder *cxl_switch_decoder_alloc(struct cxl_port *port,
721 						    unsigned int nr_targets);
722 int cxl_decoder_add(struct cxl_decoder *cxld, int *target_map);
723 struct cxl_endpoint_decoder *cxl_endpoint_decoder_alloc(struct cxl_port *port);
724 int cxl_decoder_add_locked(struct cxl_decoder *cxld, int *target_map);
725 int cxl_decoder_autoremove(struct device *host, struct cxl_decoder *cxld);
726 int cxl_endpoint_autoremove(struct cxl_memdev *cxlmd, struct cxl_port *endpoint);
727 
728 /**
729  * struct cxl_endpoint_dvsec_info - Cached DVSEC info
730  * @mem_enabled: cached value of mem_enabled in the DVSEC at init time
731  * @ranges: Number of active HDM ranges this device uses.
732  * @port: endpoint port associated with this info instance
733  * @dvsec_range: cached attributes of the ranges in the DVSEC, PCIE_DEVICE
734  */
735 struct cxl_endpoint_dvsec_info {
736 	bool mem_enabled;
737 	int ranges;
738 	struct cxl_port *port;
739 	struct range dvsec_range[2];
740 };
741 
742 struct cxl_hdm;
743 struct cxl_hdm *devm_cxl_setup_hdm(struct cxl_port *port,
744 				   struct cxl_endpoint_dvsec_info *info);
745 int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm,
746 				struct cxl_endpoint_dvsec_info *info);
747 int devm_cxl_add_passthrough_decoder(struct cxl_port *port);
748 int cxl_dvsec_rr_decode(struct device *dev, int dvsec,
749 			struct cxl_endpoint_dvsec_info *info);
750 
751 bool is_cxl_region(struct device *dev);
752 
753 extern struct bus_type cxl_bus_type;
754 
755 struct cxl_driver {
756 	const char *name;
757 	int (*probe)(struct device *dev);
758 	void (*remove)(struct device *dev);
759 	struct device_driver drv;
760 	int id;
761 };
762 
763 static inline struct cxl_driver *to_cxl_drv(struct device_driver *drv)
764 {
765 	return container_of(drv, struct cxl_driver, drv);
766 }
767 
768 int __cxl_driver_register(struct cxl_driver *cxl_drv, struct module *owner,
769 			  const char *modname);
770 #define cxl_driver_register(x) __cxl_driver_register(x, THIS_MODULE, KBUILD_MODNAME)
771 void cxl_driver_unregister(struct cxl_driver *cxl_drv);
772 
773 #define module_cxl_driver(__cxl_driver) \
774 	module_driver(__cxl_driver, cxl_driver_register, cxl_driver_unregister)
775 
776 #define CXL_DEVICE_NVDIMM_BRIDGE	1
777 #define CXL_DEVICE_NVDIMM		2
778 #define CXL_DEVICE_PORT			3
779 #define CXL_DEVICE_ROOT			4
780 #define CXL_DEVICE_MEMORY_EXPANDER	5
781 #define CXL_DEVICE_REGION		6
782 #define CXL_DEVICE_PMEM_REGION		7
783 #define CXL_DEVICE_DAX_REGION		8
784 #define CXL_DEVICE_PMU			9
785 
786 #define MODULE_ALIAS_CXL(type) MODULE_ALIAS("cxl:t" __stringify(type) "*")
787 #define CXL_MODALIAS_FMT "cxl:t%d"
788 
789 struct cxl_nvdimm_bridge *to_cxl_nvdimm_bridge(struct device *dev);
790 struct cxl_nvdimm_bridge *devm_cxl_add_nvdimm_bridge(struct device *host,
791 						     struct cxl_port *port);
792 struct cxl_nvdimm *to_cxl_nvdimm(struct device *dev);
793 bool is_cxl_nvdimm(struct device *dev);
794 bool is_cxl_nvdimm_bridge(struct device *dev);
795 int devm_cxl_add_nvdimm(struct cxl_memdev *cxlmd);
796 struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_memdev *cxlmd);
797 
798 #ifdef CONFIG_CXL_REGION
799 bool is_cxl_pmem_region(struct device *dev);
800 struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev);
801 int cxl_add_to_region(struct cxl_port *root,
802 		      struct cxl_endpoint_decoder *cxled);
803 struct cxl_dax_region *to_cxl_dax_region(struct device *dev);
804 #else
805 static inline bool is_cxl_pmem_region(struct device *dev)
806 {
807 	return false;
808 }
809 static inline struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev)
810 {
811 	return NULL;
812 }
813 static inline int cxl_add_to_region(struct cxl_port *root,
814 				    struct cxl_endpoint_decoder *cxled)
815 {
816 	return 0;
817 }
818 static inline struct cxl_dax_region *to_cxl_dax_region(struct device *dev)
819 {
820 	return NULL;
821 }
822 #endif
823 
824 /*
825  * Unit test builds overrides this to __weak, find the 'strong' version
826  * of these symbols in tools/testing/cxl/.
827  */
828 #ifndef __mock
829 #define __mock static
830 #endif
831 
832 #endif /* __CXL_H__ */
833