1 /* SPDX-License-Identifier: GPL-2.0-only */
2 /* Copyright(c) 2020 Intel Corporation. */
7 #include <linux/libnvdimm.h>
8 #include <linux/bitfield.h>
9 #include <linux/bitops.h>
10 #include <linux/log2.h>
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).
21 /* CXL 2.0 8.2.4 CXL Component Register Layout and Definition */
22 #define CXL_COMPONENT_REG_BLOCK_SIZE SZ_64K
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)
36 #define CXL_CM_CAP_CAP_ID_HDM 0x5
37 #define CXL_CM_CAP_CAP_HDM_VERSION 1
39 /* HDM decoders CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure */
40 #define CXL_HDM_DECODER_CAP_OFFSET 0x0
41 #define CXL_HDM_DECODER_COUNT_MASK GENMASK(3, 0)
42 #define CXL_HDM_DECODER_TARGET_COUNT_MASK GENMASK(7, 4)
43 #define CXL_HDM_DECODER_INTERLEAVE_11_8 BIT(8)
44 #define CXL_HDM_DECODER_INTERLEAVE_14_12 BIT(9)
45 #define CXL_HDM_DECODER_CTRL_OFFSET 0x4
46 #define CXL_HDM_DECODER_ENABLE BIT(1)
47 #define CXL_HDM_DECODER0_BASE_LOW_OFFSET(i) (0x20 * (i) + 0x10)
48 #define CXL_HDM_DECODER0_BASE_HIGH_OFFSET(i) (0x20 * (i) + 0x14)
49 #define CXL_HDM_DECODER0_SIZE_LOW_OFFSET(i) (0x20 * (i) + 0x18)
50 #define CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(i) (0x20 * (i) + 0x1c)
51 #define CXL_HDM_DECODER0_CTRL_OFFSET(i) (0x20 * (i) + 0x20)
52 #define CXL_HDM_DECODER0_CTRL_IG_MASK GENMASK(3, 0)
53 #define CXL_HDM_DECODER0_CTRL_IW_MASK GENMASK(7, 4)
54 #define CXL_HDM_DECODER0_CTRL_LOCK BIT(8)
55 #define CXL_HDM_DECODER0_CTRL_COMMIT BIT(9)
56 #define CXL_HDM_DECODER0_CTRL_COMMITTED BIT(10)
57 #define CXL_HDM_DECODER0_CTRL_COMMIT_ERROR BIT(11)
58 #define CXL_HDM_DECODER0_CTRL_TYPE BIT(12)
59 #define CXL_HDM_DECODER0_TL_LOW(i) (0x20 * (i) + 0x24)
60 #define CXL_HDM_DECODER0_TL_HIGH(i) (0x20 * (i) + 0x28)
61 #define CXL_HDM_DECODER0_SKIP_LOW(i) CXL_HDM_DECODER0_TL_LOW(i)
62 #define CXL_HDM_DECODER0_SKIP_HIGH(i) CXL_HDM_DECODER0_TL_HIGH(i)
64 static inline int cxl_hdm_decoder_count(u32 cap_hdr)
66 int val = FIELD_GET(CXL_HDM_DECODER_COUNT_MASK, cap_hdr);
68 return val ? val * 2 : 1;
71 /* Encode defined in CXL 2.0 8.2.5.12.7 HDM Decoder Control Register */
72 static inline int cxl_to_granularity(u16 ig, unsigned int *val)
80 /* Encode defined in CXL ECN "3, 6, 12 and 16-way memory Interleaving" */
81 static inline int cxl_to_ways(u8 eniw, unsigned int *val)
88 *val = 3 << (eniw - 8);
97 static inline int granularity_to_cxl(int g, u16 *ig)
99 if (g > SZ_16K || g < 256 || !is_power_of_2(g))
105 static inline int ways_to_cxl(unsigned int ways, u8 *iw)
109 if (is_power_of_2(ways)) {
116 if (!is_power_of_2(ways))
118 *iw = ilog2(ways) + 8;
122 /* CXL 2.0 8.2.8.1 Device Capabilities Array Register */
123 #define CXLDEV_CAP_ARRAY_OFFSET 0x0
124 #define CXLDEV_CAP_ARRAY_CAP_ID 0
125 #define CXLDEV_CAP_ARRAY_ID_MASK GENMASK_ULL(15, 0)
126 #define CXLDEV_CAP_ARRAY_COUNT_MASK GENMASK_ULL(47, 32)
127 /* CXL 2.0 8.2.8.2 CXL Device Capability Header Register */
128 #define CXLDEV_CAP_HDR_CAP_ID_MASK GENMASK(15, 0)
129 /* CXL 2.0 8.2.8.2.1 CXL Device Capabilities */
130 #define CXLDEV_CAP_CAP_ID_DEVICE_STATUS 0x1
131 #define CXLDEV_CAP_CAP_ID_PRIMARY_MAILBOX 0x2
132 #define CXLDEV_CAP_CAP_ID_SECONDARY_MAILBOX 0x3
133 #define CXLDEV_CAP_CAP_ID_MEMDEV 0x4000
135 /* CXL 2.0 8.2.8.4 Mailbox Registers */
136 #define CXLDEV_MBOX_CAPS_OFFSET 0x00
137 #define CXLDEV_MBOX_CAP_PAYLOAD_SIZE_MASK GENMASK(4, 0)
138 #define CXLDEV_MBOX_CTRL_OFFSET 0x04
139 #define CXLDEV_MBOX_CTRL_DOORBELL BIT(0)
140 #define CXLDEV_MBOX_CMD_OFFSET 0x08
141 #define CXLDEV_MBOX_CMD_COMMAND_OPCODE_MASK GENMASK_ULL(15, 0)
142 #define CXLDEV_MBOX_CMD_PAYLOAD_LENGTH_MASK GENMASK_ULL(36, 16)
143 #define CXLDEV_MBOX_STATUS_OFFSET 0x10
144 #define CXLDEV_MBOX_STATUS_RET_CODE_MASK GENMASK_ULL(47, 32)
145 #define CXLDEV_MBOX_BG_CMD_STATUS_OFFSET 0x18
146 #define CXLDEV_MBOX_PAYLOAD_OFFSET 0x20
149 * Using struct_group() allows for per register-block-type helper routines,
150 * without requiring block-type agnostic code to include the prefix.
154 * Common set of CXL Component register block base pointers
155 * @hdm_decoder: CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure
157 struct_group_tagged(cxl_component_regs, component,
158 void __iomem *hdm_decoder;
161 * Common set of CXL Device register block base pointers
162 * @status: CXL 2.0 8.2.8.3 Device Status Registers
163 * @mbox: CXL 2.0 8.2.8.4 Mailbox Registers
164 * @memdev: CXL 2.0 8.2.8.5 Memory Device Registers
166 struct_group_tagged(cxl_device_regs, device_regs,
167 void __iomem *status, *mbox, *memdev;
173 unsigned long offset;
177 struct cxl_component_reg_map {
178 struct cxl_reg_map hdm_decoder;
181 struct cxl_device_reg_map {
182 struct cxl_reg_map status;
183 struct cxl_reg_map mbox;
184 struct cxl_reg_map memdev;
188 * struct cxl_register_map - DVSEC harvested register block mapping parameters
189 * @base: virtual base of the register-block-BAR + @block_offset
190 * @block_offset: offset to start of register block in @barno
191 * @reg_type: see enum cxl_regloc_type
192 * @barno: PCI BAR number containing the register block
193 * @component_map: cxl_reg_map for component registers
194 * @device_map: cxl_reg_maps for device registers
196 struct cxl_register_map {
202 struct cxl_component_reg_map component_map;
203 struct cxl_device_reg_map device_map;
207 void cxl_probe_component_regs(struct device *dev, void __iomem *base,
208 struct cxl_component_reg_map *map);
209 void cxl_probe_device_regs(struct device *dev, void __iomem *base,
210 struct cxl_device_reg_map *map);
211 int cxl_map_component_regs(struct pci_dev *pdev,
212 struct cxl_component_regs *regs,
213 struct cxl_register_map *map);
214 int cxl_map_device_regs(struct pci_dev *pdev,
215 struct cxl_device_regs *regs,
216 struct cxl_register_map *map);
218 enum cxl_regloc_type;
219 int cxl_find_regblock(struct pci_dev *pdev, enum cxl_regloc_type type,
220 struct cxl_register_map *map);
221 void __iomem *devm_cxl_iomap_block(struct device *dev, resource_size_t addr,
222 resource_size_t length);
224 #define CXL_RESOURCE_NONE ((resource_size_t) -1)
225 #define CXL_TARGET_STRLEN 20
228 * cxl_decoder flags that define the type of memory / devices this
229 * decoder supports as well as configuration lock status See "CXL 2.0
230 * 8.2.5.12.7 CXL HDM Decoder 0 Control Register" for details.
232 #define CXL_DECODER_F_RAM BIT(0)
233 #define CXL_DECODER_F_PMEM BIT(1)
234 #define CXL_DECODER_F_TYPE2 BIT(2)
235 #define CXL_DECODER_F_TYPE3 BIT(3)
236 #define CXL_DECODER_F_LOCK BIT(4)
237 #define CXL_DECODER_F_ENABLE BIT(5)
238 #define CXL_DECODER_F_MASK GENMASK(5, 0)
240 enum cxl_decoder_type {
241 CXL_DECODER_ACCELERATOR = 2,
242 CXL_DECODER_EXPANDER = 3,
246 * Current specification goes up to 8, double that seems a reasonable
247 * software max for the foreseeable future
249 #define CXL_DECODER_MAX_INTERLEAVE 16
251 #define CXL_DECODER_MIN_GRANULARITY 256
254 * struct cxl_decoder - Common CXL HDM Decoder Attributes
255 * @dev: this decoder's device
256 * @id: kernel device name id
257 * @hpa_range: Host physical address range mapped by this decoder
258 * @interleave_ways: number of cxl_dports in this decode
259 * @interleave_granularity: data stride per dport
260 * @target_type: accelerator vs expander (type2 vs type3) selector
261 * @region: currently assigned region for this decoder
262 * @flags: memory type capabilities and locking
263 * @commit: device/decoder-type specific callback to commit settings to hw
264 * @reset: device/decoder-type specific callback to reset hw settings
269 struct range hpa_range;
271 int interleave_granularity;
272 enum cxl_decoder_type target_type;
273 struct cxl_region *region;
275 int (*commit)(struct cxl_decoder *cxld);
276 int (*reset)(struct cxl_decoder *cxld);
280 * CXL_DECODER_DEAD prevents endpoints from being reattached to regions
281 * while cxld_unregister() is running
283 enum cxl_decoder_mode {
292 * struct cxl_endpoint_decoder - Endpoint / SPA to DPA decoder
293 * @cxld: base cxl_decoder_object
294 * @dpa_res: actively claimed DPA span of this decoder
295 * @skip: offset into @dpa_res where @cxld.hpa_range maps
296 * @mode: which memory type / access-mode-partition this decoder targets
297 * @pos: interleave position in @cxld.region
299 struct cxl_endpoint_decoder {
300 struct cxl_decoder cxld;
301 struct resource *dpa_res;
302 resource_size_t skip;
303 enum cxl_decoder_mode mode;
308 * struct cxl_switch_decoder - Switch specific CXL HDM Decoder
309 * @cxld: base cxl_decoder object
310 * @target_lock: coordinate coherent reads of the target list
311 * @nr_targets: number of elements in @target
312 * @target: active ordered target list in current decoder configuration
314 * The 'switch' decoder type represents the decoder instances of cxl_port's that
315 * route from the root of a CXL memory decode topology to the endpoints. They
316 * come in two flavors, root-level decoders, statically defined by platform
317 * firmware, and mid-level decoders, where interleave-granularity,
318 * interleave-width, and the target list are mutable.
320 struct cxl_switch_decoder {
321 struct cxl_decoder cxld;
322 seqlock_t target_lock;
324 struct cxl_dport *target[];
329 * struct cxl_root_decoder - Static platform CXL address decoder
330 * @res: host / parent resource for region allocations
331 * @region_id: region id for next region provisioning event
332 * @calc_hb: which host bridge covers the n'th position by granularity
333 * @cxlsd: base cxl switch decoder
335 struct cxl_root_decoder {
336 struct resource *res;
338 struct cxl_dport *(*calc_hb)(struct cxl_root_decoder *cxlrd, int pos);
339 struct cxl_switch_decoder cxlsd;
343 * enum cxl_config_state - State machine for region configuration
344 * @CXL_CONFIG_IDLE: Any sysfs attribute can be written freely
345 * @CXL_CONFIG_INTERLEAVE_ACTIVE: region size has been set, no more
346 * changes to interleave_ways or interleave_granularity
347 * @CXL_CONFIG_ACTIVE: All targets have been added the region is now
349 * @CXL_CONFIG_RESET_PENDING: see commit_store()
350 * @CXL_CONFIG_COMMIT: Soft-config has been committed to hardware
352 enum cxl_config_state {
354 CXL_CONFIG_INTERLEAVE_ACTIVE,
356 CXL_CONFIG_RESET_PENDING,
361 * struct cxl_region_params - region settings
362 * @state: allow the driver to lockdown further parameter changes
363 * @uuid: unique id for persistent regions
364 * @interleave_ways: number of endpoints in the region
365 * @interleave_granularity: capacity each endpoint contributes to a stripe
366 * @res: allocated iomem capacity for this region
367 * @targets: active ordered targets in current decoder configuration
368 * @nr_targets: number of targets
370 * State transitions are protected by the cxl_region_rwsem
372 struct cxl_region_params {
373 enum cxl_config_state state;
376 int interleave_granularity;
377 struct resource *res;
378 struct cxl_endpoint_decoder *targets[CXL_DECODER_MAX_INTERLEAVE];
383 * struct cxl_region - CXL region
384 * @dev: This region's device
385 * @id: This region's id. Id is globally unique across all regions
386 * @mode: Endpoint decoder allocation / access mode
387 * @type: Endpoint decoder target type
388 * @params: active + config params for the region
393 enum cxl_decoder_mode mode;
394 enum cxl_decoder_type type;
395 struct cxl_region_params params;
399 * enum cxl_nvdimm_brige_state - state machine for managing bus rescans
400 * @CXL_NVB_NEW: Set at bridge create and after cxl_pmem_wq is destroyed
401 * @CXL_NVB_DEAD: Set at brige unregistration to preclude async probing
402 * @CXL_NVB_ONLINE: Target state after successful ->probe()
403 * @CXL_NVB_OFFLINE: Target state after ->remove() or failed ->probe()
405 enum cxl_nvdimm_brige_state {
412 struct cxl_nvdimm_bridge {
415 struct cxl_port *port;
416 struct nvdimm_bus *nvdimm_bus;
417 struct nvdimm_bus_descriptor nd_desc;
418 struct work_struct state_work;
419 enum cxl_nvdimm_brige_state state;
424 struct cxl_memdev *cxlmd;
425 struct cxl_nvdimm_bridge *bridge;
426 struct cxl_pmem_region *region;
429 struct cxl_pmem_region_mapping {
430 struct cxl_memdev *cxlmd;
431 struct cxl_nvdimm *cxl_nvd;
437 struct cxl_pmem_region {
439 struct cxl_region *cxlr;
440 struct nd_region *nd_region;
441 struct cxl_nvdimm_bridge *bridge;
442 struct range hpa_range;
444 struct cxl_pmem_region_mapping mapping[];
448 * struct cxl_port - logical collection of upstream port devices and
449 * downstream port devices to construct a CXL memory
451 * @dev: this port's device
452 * @uport: PCI or platform device implementing the upstream port capability
453 * @host_bridge: Shortcut to the platform attach point for this port
454 * @id: id for port device-name
455 * @dports: cxl_dport instances referenced by decoders
456 * @endpoints: cxl_ep instances, endpoints that are a descendant of this port
457 * @regions: cxl_region_ref instances, regions mapped by this port
458 * @parent_dport: dport that points to this port in the parent
459 * @decoder_ida: allocator for decoder ids
460 * @hdm_end: track last allocated HDM decoder instance for allocation ordering
461 * @commit_end: cursor to track highest committed decoder for commit ordering
462 * @component_reg_phys: component register capability base address (optional)
463 * @dead: last ep has been removed, force port re-creation
464 * @depth: How deep this port is relative to the root. depth 0 is the root.
465 * @cdat: Cached CDAT data
466 * @cdat_available: Should a CDAT attribute be available in sysfs
470 struct device *uport;
471 struct device *host_bridge;
473 struct xarray dports;
474 struct xarray endpoints;
475 struct xarray regions;
476 struct cxl_dport *parent_dport;
477 struct ida decoder_ida;
480 resource_size_t component_reg_phys;
490 static inline struct cxl_dport *
491 cxl_find_dport_by_dev(struct cxl_port *port, const struct device *dport_dev)
493 return xa_load(&port->dports, (unsigned long)dport_dev);
497 * struct cxl_dport - CXL downstream port
498 * @dport: PCI bridge or firmware device representing the downstream link
499 * @port_id: unique hardware identifier for dport in decoder target list
500 * @component_reg_phys: downstream port component registers
501 * @port: reference to cxl_port that contains this downstream port
504 struct device *dport;
506 resource_size_t component_reg_phys;
507 struct cxl_port *port;
511 * struct cxl_ep - track an endpoint's interest in a port
512 * @ep: device that hosts a generic CXL endpoint (expander or accelerator)
513 * @dport: which dport routes to this endpoint on @port
514 * @next: cxl switch port across the link attached to @dport NULL if
515 * attached to an endpoint
519 struct cxl_dport *dport;
520 struct cxl_port *next;
524 * struct cxl_region_ref - track a region's interest in a port
525 * @port: point in topology to install this reference
526 * @decoder: decoder assigned for @region in @port
527 * @region: region for this reference
528 * @endpoints: cxl_ep references for region members beneath @port
529 * @nr_targets_set: track how many targets have been programmed during setup
530 * @nr_eps: number of endpoints beneath @port
531 * @nr_targets: number of distinct targets needed to reach @nr_eps
533 struct cxl_region_ref {
534 struct cxl_port *port;
535 struct cxl_decoder *decoder;
536 struct cxl_region *region;
537 struct xarray endpoints;
544 * The platform firmware device hosting the root is also the top of the
545 * CXL port topology. All other CXL ports have another CXL port as their
546 * parent and their ->uport / host device is out-of-line of the port
549 static inline bool is_cxl_root(struct cxl_port *port)
551 return port->uport == port->dev.parent;
554 bool is_cxl_port(struct device *dev);
555 struct cxl_port *to_cxl_port(struct device *dev);
557 int devm_cxl_register_pci_bus(struct device *host, struct device *uport,
558 struct pci_bus *bus);
559 struct pci_bus *cxl_port_to_pci_bus(struct cxl_port *port);
560 struct cxl_port *devm_cxl_add_port(struct device *host, struct device *uport,
561 resource_size_t component_reg_phys,
562 struct cxl_dport *parent_dport);
563 int devm_cxl_add_endpoint(struct cxl_memdev *cxlmd,
564 struct cxl_dport *parent_dport);
565 struct cxl_port *find_cxl_root(struct device *dev);
566 int devm_cxl_enumerate_ports(struct cxl_memdev *cxlmd);
567 int cxl_bus_rescan(void);
568 struct cxl_port *cxl_mem_find_port(struct cxl_memdev *cxlmd,
569 struct cxl_dport **dport);
570 bool schedule_cxl_memdev_detach(struct cxl_memdev *cxlmd);
572 struct cxl_dport *devm_cxl_add_dport(struct cxl_port *port,
573 struct device *dport, int port_id,
574 resource_size_t component_reg_phys);
576 struct cxl_decoder *to_cxl_decoder(struct device *dev);
577 struct cxl_root_decoder *to_cxl_root_decoder(struct device *dev);
578 struct cxl_endpoint_decoder *to_cxl_endpoint_decoder(struct device *dev);
579 bool is_root_decoder(struct device *dev);
580 bool is_endpoint_decoder(struct device *dev);
581 struct cxl_root_decoder *cxl_root_decoder_alloc(struct cxl_port *port,
582 unsigned int nr_targets);
583 struct cxl_switch_decoder *cxl_switch_decoder_alloc(struct cxl_port *port,
584 unsigned int nr_targets);
585 int cxl_decoder_add(struct cxl_decoder *cxld, int *target_map);
586 struct cxl_endpoint_decoder *cxl_endpoint_decoder_alloc(struct cxl_port *port);
587 int cxl_decoder_add_locked(struct cxl_decoder *cxld, int *target_map);
588 int cxl_decoder_autoremove(struct device *host, struct cxl_decoder *cxld);
589 int cxl_endpoint_autoremove(struct cxl_memdev *cxlmd, struct cxl_port *endpoint);
592 struct cxl_hdm *devm_cxl_setup_hdm(struct cxl_port *port);
593 int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm);
594 int devm_cxl_add_passthrough_decoder(struct cxl_port *port);
596 bool is_cxl_region(struct device *dev);
598 extern struct bus_type cxl_bus_type;
602 int (*probe)(struct device *dev);
603 void (*remove)(struct device *dev);
604 struct device_driver drv;
608 static inline struct cxl_driver *to_cxl_drv(struct device_driver *drv)
610 return container_of(drv, struct cxl_driver, drv);
613 int __cxl_driver_register(struct cxl_driver *cxl_drv, struct module *owner,
614 const char *modname);
615 #define cxl_driver_register(x) __cxl_driver_register(x, THIS_MODULE, KBUILD_MODNAME)
616 void cxl_driver_unregister(struct cxl_driver *cxl_drv);
618 #define module_cxl_driver(__cxl_driver) \
619 module_driver(__cxl_driver, cxl_driver_register, cxl_driver_unregister)
621 #define CXL_DEVICE_NVDIMM_BRIDGE 1
622 #define CXL_DEVICE_NVDIMM 2
623 #define CXL_DEVICE_PORT 3
624 #define CXL_DEVICE_ROOT 4
625 #define CXL_DEVICE_MEMORY_EXPANDER 5
626 #define CXL_DEVICE_REGION 6
627 #define CXL_DEVICE_PMEM_REGION 7
629 #define MODULE_ALIAS_CXL(type) MODULE_ALIAS("cxl:t" __stringify(type) "*")
630 #define CXL_MODALIAS_FMT "cxl:t%d"
632 struct cxl_nvdimm_bridge *to_cxl_nvdimm_bridge(struct device *dev);
633 struct cxl_nvdimm_bridge *devm_cxl_add_nvdimm_bridge(struct device *host,
634 struct cxl_port *port);
635 struct cxl_nvdimm *to_cxl_nvdimm(struct device *dev);
636 bool is_cxl_nvdimm(struct device *dev);
637 bool is_cxl_nvdimm_bridge(struct device *dev);
638 int devm_cxl_add_nvdimm(struct device *host, struct cxl_memdev *cxlmd);
639 struct cxl_nvdimm_bridge *cxl_find_nvdimm_bridge(struct device *dev);
641 #ifdef CONFIG_CXL_REGION
642 bool is_cxl_pmem_region(struct device *dev);
643 struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev);
645 static inline bool is_cxl_pmem_region(struct device *dev)
649 static inline struct cxl_pmem_region *to_cxl_pmem_region(struct device *dev)
656 * Unit test builds overrides this to __weak, find the 'strong' version
657 * of these symbols in tools/testing/cxl/.
660 #define __mock static
663 #endif /* __CXL_H__ */