xref: /kernel/linux/linux-6.6/drivers/cxl/cxl.h (revision 62306a36)
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
69static 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 */
77static 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" */
86static 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
102static 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
111static 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 */
201struct 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
226struct cxl_reg_map {
227	bool valid;
228	int id;
229	unsigned long offset;
230	unsigned long size;
231};
232
233struct cxl_component_reg_map {
234	struct cxl_reg_map hdm_decoder;
235	struct cxl_reg_map ras;
236};
237
238struct cxl_device_reg_map {
239	struct cxl_reg_map status;
240	struct cxl_reg_map mbox;
241	struct cxl_reg_map memdev;
242};
243
244struct 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 */
259struct 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
272void cxl_probe_component_regs(struct device *dev, void __iomem *base,
273			      struct cxl_component_reg_map *map);
274void cxl_probe_device_regs(struct device *dev, void __iomem *base,
275			   struct cxl_device_reg_map *map);
276int cxl_map_component_regs(const struct cxl_register_map *map,
277			   struct cxl_component_regs *regs,
278			   unsigned long map_mask);
279int cxl_map_device_regs(const struct cxl_register_map *map,
280			struct cxl_device_regs *regs);
281int cxl_map_pmu_regs(struct pci_dev *pdev, struct cxl_pmu_regs *regs,
282		     struct cxl_register_map *map);
283
284enum cxl_regloc_type;
285int cxl_count_regblock(struct pci_dev *pdev, enum cxl_regloc_type type);
286int cxl_find_regblock_instance(struct pci_dev *pdev, enum cxl_regloc_type type,
287			       struct cxl_register_map *map, int index);
288int cxl_find_regblock(struct pci_dev *pdev, enum cxl_regloc_type type,
289		      struct cxl_register_map *map);
290int cxl_setup_regs(struct cxl_register_map *map);
291struct cxl_dport;
292resource_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
313enum 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*/
338struct 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 */
355enum 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
363static 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 */
381enum 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 */
395struct 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 * @nr_targets: number of elements in @target
408 * @target: active ordered target list in current decoder configuration
409 *
410 * The 'switch' decoder type represents the decoder instances of cxl_port's that
411 * route from the root of a CXL memory decode topology to the endpoints. They
412 * come in two flavors, root-level decoders, statically defined by platform
413 * firmware, and mid-level decoders, where interleave-granularity,
414 * interleave-width, and the target list are mutable.
415 */
416struct cxl_switch_decoder {
417	struct cxl_decoder cxld;
418	int nr_targets;
419	struct cxl_dport *target[];
420};
421
422struct cxl_root_decoder;
423typedef struct cxl_dport *(*cxl_calc_hb_fn)(struct cxl_root_decoder *cxlrd,
424					    int pos);
425
426/**
427 * struct cxl_root_decoder - Static platform CXL address decoder
428 * @res: host / parent resource for region allocations
429 * @region_id: region id for next region provisioning event
430 * @calc_hb: which host bridge covers the n'th position by granularity
431 * @platform_data: platform specific configuration data
432 * @range_lock: sync region autodiscovery by address range
433 * @cxlsd: base cxl switch decoder
434 */
435struct cxl_root_decoder {
436	struct resource *res;
437	atomic_t region_id;
438	cxl_calc_hb_fn calc_hb;
439	void *platform_data;
440	struct mutex range_lock;
441	struct cxl_switch_decoder cxlsd;
442};
443
444/*
445 * enum cxl_config_state - State machine for region configuration
446 * @CXL_CONFIG_IDLE: Any sysfs attribute can be written freely
447 * @CXL_CONFIG_INTERLEAVE_ACTIVE: region size has been set, no more
448 * changes to interleave_ways or interleave_granularity
449 * @CXL_CONFIG_ACTIVE: All targets have been added the region is now
450 * active
451 * @CXL_CONFIG_RESET_PENDING: see commit_store()
452 * @CXL_CONFIG_COMMIT: Soft-config has been committed to hardware
453 */
454enum cxl_config_state {
455	CXL_CONFIG_IDLE,
456	CXL_CONFIG_INTERLEAVE_ACTIVE,
457	CXL_CONFIG_ACTIVE,
458	CXL_CONFIG_RESET_PENDING,
459	CXL_CONFIG_COMMIT,
460};
461
462/**
463 * struct cxl_region_params - region settings
464 * @state: allow the driver to lockdown further parameter changes
465 * @uuid: unique id for persistent regions
466 * @interleave_ways: number of endpoints in the region
467 * @interleave_granularity: capacity each endpoint contributes to a stripe
468 * @res: allocated iomem capacity for this region
469 * @targets: active ordered targets in current decoder configuration
470 * @nr_targets: number of targets
471 *
472 * State transitions are protected by the cxl_region_rwsem
473 */
474struct 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};
483
484/*
485 * Indicate whether this region has been assembled by autodetection or
486 * userspace assembly. Prevent endpoint decoders outside of automatic
487 * detection from being added to the region.
488 */
489#define CXL_REGION_F_AUTO 0
490
491/*
492 * Require that a committed region successfully complete a teardown once
493 * any of its associated decoders have been torn down. This maintains
494 * the commit state for the region since there are committed decoders,
495 * but blocks cxl_region_probe().
496 */
497#define CXL_REGION_F_NEEDS_RESET 1
498
499/**
500 * struct cxl_region - CXL region
501 * @dev: This region's device
502 * @id: This region's id. Id is globally unique across all regions
503 * @mode: Endpoint decoder allocation / access mode
504 * @type: Endpoint decoder target type
505 * @cxl_nvb: nvdimm bridge for coordinating @cxlr_pmem setup / shutdown
506 * @cxlr_pmem: (for pmem regions) cached copy of the nvdimm bridge
507 * @flags: Region state flags
508 * @params: active + config params for the region
509 */
510struct cxl_region {
511	struct device dev;
512	int id;
513	enum cxl_decoder_mode mode;
514	enum cxl_decoder_type type;
515	struct cxl_nvdimm_bridge *cxl_nvb;
516	struct cxl_pmem_region *cxlr_pmem;
517	unsigned long flags;
518	struct cxl_region_params params;
519};
520
521struct cxl_nvdimm_bridge {
522	int id;
523	struct device dev;
524	struct cxl_port *port;
525	struct nvdimm_bus *nvdimm_bus;
526	struct nvdimm_bus_descriptor nd_desc;
527};
528
529#define CXL_DEV_ID_LEN 19
530
531struct cxl_nvdimm {
532	struct device dev;
533	struct cxl_memdev *cxlmd;
534	u8 dev_id[CXL_DEV_ID_LEN]; /* for nvdimm, string of 'serial' */
535};
536
537struct cxl_pmem_region_mapping {
538	struct cxl_memdev *cxlmd;
539	struct cxl_nvdimm *cxl_nvd;
540	u64 start;
541	u64 size;
542	int position;
543};
544
545struct cxl_pmem_region {
546	struct device dev;
547	struct cxl_region *cxlr;
548	struct nd_region *nd_region;
549	struct range hpa_range;
550	int nr_mappings;
551	struct cxl_pmem_region_mapping mapping[];
552};
553
554struct cxl_dax_region {
555	struct device dev;
556	struct cxl_region *cxlr;
557	struct range hpa_range;
558};
559
560/**
561 * struct cxl_port - logical collection of upstream port devices and
562 *		     downstream port devices to construct a CXL memory
563 *		     decode hierarchy.
564 * @dev: this port's device
565 * @uport_dev: PCI or platform device implementing the upstream port capability
566 * @host_bridge: Shortcut to the platform attach point for this port
567 * @id: id for port device-name
568 * @dports: cxl_dport instances referenced by decoders
569 * @endpoints: cxl_ep instances, endpoints that are a descendant of this port
570 * @regions: cxl_region_ref instances, regions mapped by this port
571 * @parent_dport: dport that points to this port in the parent
572 * @decoder_ida: allocator for decoder ids
573 * @comp_map: component register capability mappings
574 * @nr_dports: number of entries in @dports
575 * @hdm_end: track last allocated HDM decoder instance for allocation ordering
576 * @commit_end: cursor to track highest committed decoder for commit ordering
577 * @component_reg_phys: component register capability base address (optional)
578 * @dead: last ep has been removed, force port re-creation
579 * @depth: How deep this port is relative to the root. depth 0 is the root.
580 * @cdat: Cached CDAT data
581 * @cdat_available: Should a CDAT attribute be available in sysfs
582 */
583struct cxl_port {
584	struct device dev;
585	struct device *uport_dev;
586	struct device *host_bridge;
587	int id;
588	struct xarray dports;
589	struct xarray endpoints;
590	struct xarray regions;
591	struct cxl_dport *parent_dport;
592	struct ida decoder_ida;
593	struct cxl_register_map comp_map;
594	int nr_dports;
595	int hdm_end;
596	int commit_end;
597	resource_size_t component_reg_phys;
598	bool dead;
599	unsigned int depth;
600	struct cxl_cdat {
601		void *table;
602		size_t length;
603	} cdat;
604	bool cdat_available;
605};
606
607static inline struct cxl_dport *
608cxl_find_dport_by_dev(struct cxl_port *port, const struct device *dport_dev)
609{
610	return xa_load(&port->dports, (unsigned long)dport_dev);
611}
612
613struct cxl_rcrb_info {
614	resource_size_t base;
615	u16 aer_cap;
616};
617
618/**
619 * struct cxl_dport - CXL downstream port
620 * @dport_dev: PCI bridge or firmware device representing the downstream link
621 * @comp_map: component register capability mappings
622 * @port_id: unique hardware identifier for dport in decoder target list
623 * @rcrb: Data about the Root Complex Register Block layout
624 * @rch: Indicate whether this dport was enumerated in RCH or VH mode
625 * @port: reference to cxl_port that contains this downstream port
626 */
627struct cxl_dport {
628	struct device *dport_dev;
629	struct cxl_register_map comp_map;
630	int port_id;
631	struct cxl_rcrb_info rcrb;
632	bool rch;
633	struct cxl_port *port;
634};
635
636/**
637 * struct cxl_ep - track an endpoint's interest in a port
638 * @ep: device that hosts a generic CXL endpoint (expander or accelerator)
639 * @dport: which dport routes to this endpoint on @port
640 * @next: cxl switch port across the link attached to @dport NULL if
641 *	  attached to an endpoint
642 */
643struct cxl_ep {
644	struct device *ep;
645	struct cxl_dport *dport;
646	struct cxl_port *next;
647};
648
649/**
650 * struct cxl_region_ref - track a region's interest in a port
651 * @port: point in topology to install this reference
652 * @decoder: decoder assigned for @region in @port
653 * @region: region for this reference
654 * @endpoints: cxl_ep references for region members beneath @port
655 * @nr_targets_set: track how many targets have been programmed during setup
656 * @nr_eps: number of endpoints beneath @port
657 * @nr_targets: number of distinct targets needed to reach @nr_eps
658 */
659struct cxl_region_ref {
660	struct cxl_port *port;
661	struct cxl_decoder *decoder;
662	struct cxl_region *region;
663	struct xarray endpoints;
664	int nr_targets_set;
665	int nr_eps;
666	int nr_targets;
667};
668
669/*
670 * The platform firmware device hosting the root is also the top of the
671 * CXL port topology. All other CXL ports have another CXL port as their
672 * parent and their ->uport_dev / host device is out-of-line of the port
673 * ancestry.
674 */
675static inline bool is_cxl_root(struct cxl_port *port)
676{
677	return port->uport_dev == port->dev.parent;
678}
679
680int cxl_num_decoders_committed(struct cxl_port *port);
681bool is_cxl_port(const struct device *dev);
682struct cxl_port *to_cxl_port(const struct device *dev);
683struct pci_bus;
684int devm_cxl_register_pci_bus(struct device *host, struct device *uport_dev,
685			      struct pci_bus *bus);
686struct pci_bus *cxl_port_to_pci_bus(struct cxl_port *port);
687struct cxl_port *devm_cxl_add_port(struct device *host,
688				   struct device *uport_dev,
689				   resource_size_t component_reg_phys,
690				   struct cxl_dport *parent_dport);
691struct cxl_port *find_cxl_root(struct cxl_port *port);
692int devm_cxl_enumerate_ports(struct cxl_memdev *cxlmd);
693void cxl_bus_rescan(void);
694void cxl_bus_drain(void);
695struct cxl_port *cxl_pci_find_port(struct pci_dev *pdev,
696				   struct cxl_dport **dport);
697struct cxl_port *cxl_mem_find_port(struct cxl_memdev *cxlmd,
698				   struct cxl_dport **dport);
699bool schedule_cxl_memdev_detach(struct cxl_memdev *cxlmd);
700
701struct cxl_dport *devm_cxl_add_dport(struct cxl_port *port,
702				     struct device *dport, int port_id,
703				     resource_size_t component_reg_phys);
704struct cxl_dport *devm_cxl_add_rch_dport(struct cxl_port *port,
705					 struct device *dport_dev, int port_id,
706					 resource_size_t rcrb);
707
708struct cxl_decoder *to_cxl_decoder(struct device *dev);
709struct cxl_root_decoder *to_cxl_root_decoder(struct device *dev);
710struct cxl_switch_decoder *to_cxl_switch_decoder(struct device *dev);
711struct cxl_endpoint_decoder *to_cxl_endpoint_decoder(struct device *dev);
712bool is_root_decoder(struct device *dev);
713bool is_switch_decoder(struct device *dev);
714bool is_endpoint_decoder(struct device *dev);
715struct cxl_root_decoder *cxl_root_decoder_alloc(struct cxl_port *port,
716						unsigned int nr_targets,
717						cxl_calc_hb_fn calc_hb);
718struct cxl_dport *cxl_hb_modulo(struct cxl_root_decoder *cxlrd, int pos);
719struct cxl_switch_decoder *cxl_switch_decoder_alloc(struct cxl_port *port,
720						    unsigned int nr_targets);
721int cxl_decoder_add(struct cxl_decoder *cxld, int *target_map);
722struct cxl_endpoint_decoder *cxl_endpoint_decoder_alloc(struct cxl_port *port);
723int cxl_decoder_add_locked(struct cxl_decoder *cxld, int *target_map);
724int cxl_decoder_autoremove(struct device *host, struct cxl_decoder *cxld);
725int cxl_endpoint_autoremove(struct cxl_memdev *cxlmd, struct cxl_port *endpoint);
726
727/**
728 * struct cxl_endpoint_dvsec_info - Cached DVSEC info
729 * @mem_enabled: cached value of mem_enabled in the DVSEC at init time
730 * @ranges: Number of active HDM ranges this device uses.
731 * @port: endpoint port associated with this info instance
732 * @dvsec_range: cached attributes of the ranges in the DVSEC, PCIE_DEVICE
733 */
734struct cxl_endpoint_dvsec_info {
735	bool mem_enabled;
736	int ranges;
737	struct cxl_port *port;
738	struct range dvsec_range[2];
739};
740
741struct cxl_hdm;
742struct cxl_hdm *devm_cxl_setup_hdm(struct cxl_port *port,
743				   struct cxl_endpoint_dvsec_info *info);
744int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm,
745				struct cxl_endpoint_dvsec_info *info);
746int devm_cxl_add_passthrough_decoder(struct cxl_port *port);
747int cxl_dvsec_rr_decode(struct device *dev, int dvsec,
748			struct cxl_endpoint_dvsec_info *info);
749
750bool is_cxl_region(struct device *dev);
751
752extern struct bus_type cxl_bus_type;
753
754struct cxl_driver {
755	const char *name;
756	int (*probe)(struct device *dev);
757	void (*remove)(struct device *dev);
758	struct device_driver drv;
759	int id;
760};
761
762static inline struct cxl_driver *to_cxl_drv(struct device_driver *drv)
763{
764	return container_of(drv, struct cxl_driver, drv);
765}
766
767int __cxl_driver_register(struct cxl_driver *cxl_drv, struct module *owner,
768			  const char *modname);
769#define cxl_driver_register(x) __cxl_driver_register(x, THIS_MODULE, KBUILD_MODNAME)
770void cxl_driver_unregister(struct cxl_driver *cxl_drv);
771
772#define module_cxl_driver(__cxl_driver) \
773	module_driver(__cxl_driver, cxl_driver_register, cxl_driver_unregister)
774
775#define CXL_DEVICE_NVDIMM_BRIDGE	1
776#define CXL_DEVICE_NVDIMM		2
777#define CXL_DEVICE_PORT			3
778#define CXL_DEVICE_ROOT			4
779#define CXL_DEVICE_MEMORY_EXPANDER	5
780#define CXL_DEVICE_REGION		6
781#define CXL_DEVICE_PMEM_REGION		7
782#define CXL_DEVICE_DAX_REGION		8
783#define CXL_DEVICE_PMU			9
784
785#define MODULE_ALIAS_CXL(type) MODULE_ALIAS("cxl:t" __stringify(type) "*")
786#define CXL_MODALIAS_FMT "cxl:t%d"
787
788struct cxl_nvdimm_bridge *to_cxl_nvdimm_bridge(struct device *dev);
789struct cxl_nvdimm_bridge *devm_cxl_add_nvdimm_bridge(struct device *host,
790						     struct cxl_port *port);
791struct cxl_nvdimm *to_cxl_nvdimm(struct device *dev);
792bool is_cxl_nvdimm(struct device *dev);
793bool is_cxl_nvdimm_bridge(struct device *dev);
794int devm_cxl_add_nvdimm(struct cxl_memdev *cxlmd);
795struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct cxl_memdev *cxlmd);
796
797#ifdef CONFIG_CXL_REGION
798bool is_cxl_pmem_region(struct device *dev);
799struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev);
800int cxl_add_to_region(struct cxl_port *root,
801		      struct cxl_endpoint_decoder *cxled);
802struct cxl_dax_region *to_cxl_dax_region(struct device *dev);
803#else
804static inline bool is_cxl_pmem_region(struct device *dev)
805{
806	return false;
807}
808static inline struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev)
809{
810	return NULL;
811}
812static inline int cxl_add_to_region(struct cxl_port *root,
813				    struct cxl_endpoint_decoder *cxled)
814{
815	return 0;
816}
817static inline struct cxl_dax_region *to_cxl_dax_region(struct device *dev)
818{
819	return NULL;
820}
821#endif
822
823/*
824 * Unit test builds overrides this to __weak, find the 'strong' version
825 * of these symbols in tools/testing/cxl/.
826 */
827#ifndef __mock
828#define __mock static
829#endif
830
831#endif /* __CXL_H__ */
832