1 /* 2 * This file is provided under a dual BSD/GPLv2 license. When using or 3 * redistributing this file, you may do so under either license. 4 * 5 * GPL LICENSE SUMMARY 6 * 7 * Copyright (C) 2015 EMC Corporation. All Rights Reserved. 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of version 2 of the GNU General Public License as 11 * published by the Free Software Foundation. 12 * 13 * This program is distributed in the hope that it will be useful, but 14 * WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 * General Public License for more details. 17 * 18 * BSD LICENSE 19 * 20 * Copyright (C) 2015 EMC Corporation. All Rights Reserved. 21 * 22 * Redistribution and use in source and binary forms, with or without 23 * modification, are permitted provided that the following conditions 24 * are met: 25 * 26 * * Redistributions of source code must retain the above copyright 27 * notice, this list of conditions and the following disclaimer. 28 * * Redistributions in binary form must reproduce the above copy 29 * notice, this list of conditions and the following disclaimer in 30 * the documentation and/or other materials provided with the 31 * distribution. 32 * * Neither the name of Intel Corporation nor the names of its 33 * contributors may be used to endorse or promote products derived 34 * from this software without specific prior written permission. 35 * 36 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 37 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 38 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 39 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 40 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 41 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 42 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 43 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 44 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 45 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 46 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 47 * 48 * PCIe NTB Linux driver 49 * 50 * Contact Information: 51 * Allen Hubbe <[email protected]> 52 */ 53 54 #ifndef _NTB_H_ 55 #define _NTB_H_ 56 57 #include <linux/completion.h> 58 #include <linux/device.h> 59 60 struct ntb_client; 61 struct ntb_dev; 62 struct pci_dev; 63 64 /** 65 * enum ntb_topo - NTB connection topology 66 * @NTB_TOPO_NONE: Topology is unknown or invalid. 67 * @NTB_TOPO_PRI: On primary side of local ntb. 68 * @NTB_TOPO_SEC: On secondary side of remote ntb. 69 * @NTB_TOPO_B2B_USD: On primary side of local ntb upstream of remote ntb. 70 * @NTB_TOPO_B2B_DSD: On primary side of local ntb downstream of remote ntb. 71 */ 72 enum ntb_topo { 73 NTB_TOPO_NONE = -1, 74 NTB_TOPO_PRI, 75 NTB_TOPO_SEC, 76 NTB_TOPO_B2B_USD, 77 NTB_TOPO_B2B_DSD, 78 }; 79 80 static inline int ntb_topo_is_b2b(enum ntb_topo topo) 81 { 82 switch ((int)topo) { 83 case NTB_TOPO_B2B_USD: 84 case NTB_TOPO_B2B_DSD: 85 return 1; 86 } 87 return 0; 88 } 89 90 static inline char *ntb_topo_string(enum ntb_topo topo) 91 { 92 switch (topo) { 93 case NTB_TOPO_NONE: return "NTB_TOPO_NONE"; 94 case NTB_TOPO_PRI: return "NTB_TOPO_PRI"; 95 case NTB_TOPO_SEC: return "NTB_TOPO_SEC"; 96 case NTB_TOPO_B2B_USD: return "NTB_TOPO_B2B_USD"; 97 case NTB_TOPO_B2B_DSD: return "NTB_TOPO_B2B_DSD"; 98 } 99 return "NTB_TOPO_INVALID"; 100 } 101 102 /** 103 * enum ntb_speed - NTB link training speed 104 * @NTB_SPEED_AUTO: Request the max supported speed. 105 * @NTB_SPEED_NONE: Link is not trained to any speed. 106 * @NTB_SPEED_GEN1: Link is trained to gen1 speed. 107 * @NTB_SPEED_GEN2: Link is trained to gen2 speed. 108 * @NTB_SPEED_GEN3: Link is trained to gen3 speed. 109 */ 110 enum ntb_speed { 111 NTB_SPEED_AUTO = -1, 112 NTB_SPEED_NONE = 0, 113 NTB_SPEED_GEN1 = 1, 114 NTB_SPEED_GEN2 = 2, 115 NTB_SPEED_GEN3 = 3, 116 }; 117 118 /** 119 * enum ntb_width - NTB link training width 120 * @NTB_WIDTH_AUTO: Request the max supported width. 121 * @NTB_WIDTH_NONE: Link is not trained to any width. 122 * @NTB_WIDTH_1: Link is trained to 1 lane width. 123 * @NTB_WIDTH_2: Link is trained to 2 lane width. 124 * @NTB_WIDTH_4: Link is trained to 4 lane width. 125 * @NTB_WIDTH_8: Link is trained to 8 lane width. 126 * @NTB_WIDTH_12: Link is trained to 12 lane width. 127 * @NTB_WIDTH_16: Link is trained to 16 lane width. 128 * @NTB_WIDTH_32: Link is trained to 32 lane width. 129 */ 130 enum ntb_width { 131 NTB_WIDTH_AUTO = -1, 132 NTB_WIDTH_NONE = 0, 133 NTB_WIDTH_1 = 1, 134 NTB_WIDTH_2 = 2, 135 NTB_WIDTH_4 = 4, 136 NTB_WIDTH_8 = 8, 137 NTB_WIDTH_12 = 12, 138 NTB_WIDTH_16 = 16, 139 NTB_WIDTH_32 = 32, 140 }; 141 142 /** 143 * struct ntb_client_ops - ntb client operations 144 * @probe: Notify client of a new device. 145 * @remove: Notify client to remove a device. 146 */ 147 struct ntb_client_ops { 148 int (*probe)(struct ntb_client *client, struct ntb_dev *ntb); 149 void (*remove)(struct ntb_client *client, struct ntb_dev *ntb); 150 }; 151 152 static inline int ntb_client_ops_is_valid(const struct ntb_client_ops *ops) 153 { 154 /* commented callbacks are not required: */ 155 return 156 ops->probe && 157 ops->remove && 158 1; 159 } 160 161 /** 162 * struct ntb_ctx_ops - ntb driver context operations 163 * @link_event: See ntb_link_event(). 164 * @db_event: See ntb_db_event(). 165 */ 166 struct ntb_ctx_ops { 167 void (*link_event)(void *ctx); 168 void (*db_event)(void *ctx, int db_vector); 169 }; 170 171 static inline int ntb_ctx_ops_is_valid(const struct ntb_ctx_ops *ops) 172 { 173 /* commented callbacks are not required: */ 174 return 175 /* ops->link_event && */ 176 /* ops->db_event && */ 177 1; 178 } 179 180 /** 181 * struct ntb_ctx_ops - ntb device operations 182 * @mw_count: See ntb_mw_count(). 183 * @mw_get_range: See ntb_mw_get_range(). 184 * @mw_set_trans: See ntb_mw_set_trans(). 185 * @mw_clear_trans: See ntb_mw_clear_trans(). 186 * @link_is_up: See ntb_link_is_up(). 187 * @link_enable: See ntb_link_enable(). 188 * @link_disable: See ntb_link_disable(). 189 * @db_is_unsafe: See ntb_db_is_unsafe(). 190 * @db_valid_mask: See ntb_db_valid_mask(). 191 * @db_vector_count: See ntb_db_vector_count(). 192 * @db_vector_mask: See ntb_db_vector_mask(). 193 * @db_read: See ntb_db_read(). 194 * @db_set: See ntb_db_set(). 195 * @db_clear: See ntb_db_clear(). 196 * @db_read_mask: See ntb_db_read_mask(). 197 * @db_set_mask: See ntb_db_set_mask(). 198 * @db_clear_mask: See ntb_db_clear_mask(). 199 * @peer_db_addr: See ntb_peer_db_addr(). 200 * @peer_db_read: See ntb_peer_db_read(). 201 * @peer_db_set: See ntb_peer_db_set(). 202 * @peer_db_clear: See ntb_peer_db_clear(). 203 * @peer_db_read_mask: See ntb_peer_db_read_mask(). 204 * @peer_db_set_mask: See ntb_peer_db_set_mask(). 205 * @peer_db_clear_mask: See ntb_peer_db_clear_mask(). 206 * @spad_is_unsafe: See ntb_spad_is_unsafe(). 207 * @spad_count: See ntb_spad_count(). 208 * @spad_read: See ntb_spad_read(). 209 * @spad_write: See ntb_spad_write(). 210 * @peer_spad_addr: See ntb_peer_spad_addr(). 211 * @peer_spad_read: See ntb_peer_spad_read(). 212 * @peer_spad_write: See ntb_peer_spad_write(). 213 */ 214 struct ntb_dev_ops { 215 int (*mw_count)(struct ntb_dev *ntb); 216 int (*mw_get_range)(struct ntb_dev *ntb, int idx, 217 phys_addr_t *base, resource_size_t *size, 218 resource_size_t *align, resource_size_t *align_size); 219 int (*mw_set_trans)(struct ntb_dev *ntb, int idx, 220 dma_addr_t addr, resource_size_t size); 221 int (*mw_clear_trans)(struct ntb_dev *ntb, int idx); 222 223 int (*link_is_up)(struct ntb_dev *ntb, 224 enum ntb_speed *speed, enum ntb_width *width); 225 int (*link_enable)(struct ntb_dev *ntb, 226 enum ntb_speed max_speed, enum ntb_width max_width); 227 int (*link_disable)(struct ntb_dev *ntb); 228 229 int (*db_is_unsafe)(struct ntb_dev *ntb); 230 u64 (*db_valid_mask)(struct ntb_dev *ntb); 231 int (*db_vector_count)(struct ntb_dev *ntb); 232 u64 (*db_vector_mask)(struct ntb_dev *ntb, int db_vector); 233 234 u64 (*db_read)(struct ntb_dev *ntb); 235 int (*db_set)(struct ntb_dev *ntb, u64 db_bits); 236 int (*db_clear)(struct ntb_dev *ntb, u64 db_bits); 237 238 u64 (*db_read_mask)(struct ntb_dev *ntb); 239 int (*db_set_mask)(struct ntb_dev *ntb, u64 db_bits); 240 int (*db_clear_mask)(struct ntb_dev *ntb, u64 db_bits); 241 242 int (*peer_db_addr)(struct ntb_dev *ntb, 243 phys_addr_t *db_addr, resource_size_t *db_size); 244 u64 (*peer_db_read)(struct ntb_dev *ntb); 245 int (*peer_db_set)(struct ntb_dev *ntb, u64 db_bits); 246 int (*peer_db_clear)(struct ntb_dev *ntb, u64 db_bits); 247 248 u64 (*peer_db_read_mask)(struct ntb_dev *ntb); 249 int (*peer_db_set_mask)(struct ntb_dev *ntb, u64 db_bits); 250 int (*peer_db_clear_mask)(struct ntb_dev *ntb, u64 db_bits); 251 252 int (*spad_is_unsafe)(struct ntb_dev *ntb); 253 int (*spad_count)(struct ntb_dev *ntb); 254 255 u32 (*spad_read)(struct ntb_dev *ntb, int idx); 256 int (*spad_write)(struct ntb_dev *ntb, int idx, u32 val); 257 258 int (*peer_spad_addr)(struct ntb_dev *ntb, int idx, 259 phys_addr_t *spad_addr); 260 u32 (*peer_spad_read)(struct ntb_dev *ntb, int idx); 261 int (*peer_spad_write)(struct ntb_dev *ntb, int idx, u32 val); 262 }; 263 264 static inline int ntb_dev_ops_is_valid(const struct ntb_dev_ops *ops) 265 { 266 /* commented callbacks are not required: */ 267 return 268 ops->mw_count && 269 ops->mw_get_range && 270 ops->mw_set_trans && 271 /* ops->mw_clear_trans && */ 272 ops->link_is_up && 273 ops->link_enable && 274 ops->link_disable && 275 /* ops->db_is_unsafe && */ 276 ops->db_valid_mask && 277 278 /* both set, or both unset */ 279 (!ops->db_vector_count == !ops->db_vector_mask) && 280 281 ops->db_read && 282 /* ops->db_set && */ 283 ops->db_clear && 284 /* ops->db_read_mask && */ 285 ops->db_set_mask && 286 ops->db_clear_mask && 287 ops->peer_db_addr && 288 /* ops->peer_db_read && */ 289 ops->peer_db_set && 290 /* ops->peer_db_clear && */ 291 /* ops->peer_db_read_mask && */ 292 /* ops->peer_db_set_mask && */ 293 /* ops->peer_db_clear_mask && */ 294 /* ops->spad_is_unsafe && */ 295 ops->spad_count && 296 ops->spad_read && 297 ops->spad_write && 298 ops->peer_spad_addr && 299 /* ops->peer_spad_read && */ 300 ops->peer_spad_write && 301 1; 302 } 303 304 /** 305 * struct ntb_client - client interested in ntb devices 306 * @drv: Linux driver object. 307 * @ops: See &ntb_client_ops. 308 */ 309 struct ntb_client { 310 struct device_driver drv; 311 const struct ntb_client_ops ops; 312 }; 313 314 #define drv_ntb_client(__drv) container_of((__drv), struct ntb_client, drv) 315 316 /** 317 * struct ntb_device - ntb device 318 * @dev: Linux device object. 319 * @pdev: Pci device entry of the ntb. 320 * @topo: Detected topology of the ntb. 321 * @ops: See &ntb_dev_ops. 322 * @ctx: See &ntb_ctx_ops. 323 * @ctx_ops: See &ntb_ctx_ops. 324 */ 325 struct ntb_dev { 326 struct device dev; 327 struct pci_dev *pdev; 328 enum ntb_topo topo; 329 const struct ntb_dev_ops *ops; 330 void *ctx; 331 const struct ntb_ctx_ops *ctx_ops; 332 333 /* private: */ 334 335 /* synchronize setting, clearing, and calling ctx_ops */ 336 spinlock_t ctx_lock; 337 /* block unregister until device is fully released */ 338 struct completion released; 339 }; 340 341 #define dev_ntb(__dev) container_of((__dev), struct ntb_dev, dev) 342 343 /** 344 * ntb_register_client() - register a client for interest in ntb devices 345 * @client: Client context. 346 * 347 * The client will be added to the list of clients interested in ntb devices. 348 * The client will be notified of any ntb devices that are not already 349 * associated with a client, or if ntb devices are registered later. 350 * 351 * Return: Zero if the client is registered, otherwise an error number. 352 */ 353 #define ntb_register_client(client) \ 354 __ntb_register_client((client), THIS_MODULE, KBUILD_MODNAME) 355 356 int __ntb_register_client(struct ntb_client *client, struct module *mod, 357 const char *mod_name); 358 359 /** 360 * ntb_unregister_client() - unregister a client for interest in ntb devices 361 * @client: Client context. 362 * 363 * The client will be removed from the list of clients interested in ntb 364 * devices. If any ntb devices are associated with the client, the client will 365 * be notified to remove those devices. 366 */ 367 void ntb_unregister_client(struct ntb_client *client); 368 369 #define module_ntb_client(__ntb_client) \ 370 module_driver(__ntb_client, ntb_register_client, \ 371 ntb_unregister_client) 372 373 /** 374 * ntb_register_device() - register a ntb device 375 * @ntb: NTB device context. 376 * 377 * The device will be added to the list of ntb devices. If any clients are 378 * interested in ntb devices, each client will be notified of the ntb device, 379 * until at most one client accepts the device. 380 * 381 * Return: Zero if the device is registered, otherwise an error number. 382 */ 383 int ntb_register_device(struct ntb_dev *ntb); 384 385 /** 386 * ntb_register_device() - unregister a ntb device 387 * @ntb: NTB device context. 388 * 389 * The device will be removed from the list of ntb devices. If the ntb device 390 * is associated with a client, the client will be notified to remove the 391 * device. 392 */ 393 void ntb_unregister_device(struct ntb_dev *ntb); 394 395 /** 396 * ntb_set_ctx() - associate a driver context with an ntb device 397 * @ntb: NTB device context. 398 * @ctx: Driver context. 399 * @ctx_ops: Driver context operations. 400 * 401 * Associate a driver context and operations with a ntb device. The context is 402 * provided by the client driver, and the driver may associate a different 403 * context with each ntb device. 404 * 405 * Return: Zero if the context is associated, otherwise an error number. 406 */ 407 int ntb_set_ctx(struct ntb_dev *ntb, void *ctx, 408 const struct ntb_ctx_ops *ctx_ops); 409 410 /** 411 * ntb_clear_ctx() - disassociate any driver context from an ntb device 412 * @ntb: NTB device context. 413 * 414 * Clear any association that may exist between a driver context and the ntb 415 * device. 416 */ 417 void ntb_clear_ctx(struct ntb_dev *ntb); 418 419 /** 420 * ntb_link_event() - notify driver context of a change in link status 421 * @ntb: NTB device context. 422 * 423 * Notify the driver context that the link status may have changed. The driver 424 * should call ntb_link_is_up() to get the current status. 425 */ 426 void ntb_link_event(struct ntb_dev *ntb); 427 428 /** 429 * ntb_db_event() - notify driver context of a doorbell event 430 * @ntb: NTB device context. 431 * @vector: Interrupt vector number. 432 * 433 * Notify the driver context of a doorbell event. If hardware supports 434 * multiple interrupt vectors for doorbells, the vector number indicates which 435 * vector received the interrupt. The vector number is relative to the first 436 * vector used for doorbells, starting at zero, and must be less than 437 ** ntb_db_vector_count(). The driver may call ntb_db_read() to check which 438 * doorbell bits need service, and ntb_db_vector_mask() to determine which of 439 * those bits are associated with the vector number. 440 */ 441 void ntb_db_event(struct ntb_dev *ntb, int vector); 442 443 /** 444 * ntb_mw_count() - get the number of memory windows 445 * @ntb: NTB device context. 446 * 447 * Hardware and topology may support a different number of memory windows. 448 * 449 * Return: the number of memory windows. 450 */ 451 static inline int ntb_mw_count(struct ntb_dev *ntb) 452 { 453 return ntb->ops->mw_count(ntb); 454 } 455 456 /** 457 * ntb_mw_get_range() - get the range of a memory window 458 * @ntb: NTB device context. 459 * @idx: Memory window number. 460 * @base: OUT - the base address for mapping the memory window 461 * @size: OUT - the size for mapping the memory window 462 * @align: OUT - the base alignment for translating the memory window 463 * @align_size: OUT - the size alignment for translating the memory window 464 * 465 * Get the range of a memory window. NULL may be given for any output 466 * parameter if the value is not needed. The base and size may be used for 467 * mapping the memory window, to access the peer memory. The alignment and 468 * size may be used for translating the memory window, for the peer to access 469 * memory on the local system. 470 * 471 * Return: Zero on success, otherwise an error number. 472 */ 473 static inline int ntb_mw_get_range(struct ntb_dev *ntb, int idx, 474 phys_addr_t *base, resource_size_t *size, 475 resource_size_t *align, resource_size_t *align_size) 476 { 477 return ntb->ops->mw_get_range(ntb, idx, base, size, 478 align, align_size); 479 } 480 481 /** 482 * ntb_mw_set_trans() - set the translation of a memory window 483 * @ntb: NTB device context. 484 * @idx: Memory window number. 485 * @addr: The dma address local memory to expose to the peer. 486 * @size: The size of the local memory to expose to the peer. 487 * 488 * Set the translation of a memory window. The peer may access local memory 489 * through the window starting at the address, up to the size. The address 490 * must be aligned to the alignment specified by ntb_mw_get_range(). The size 491 * must be aligned to the size alignment specified by ntb_mw_get_range(). 492 * 493 * Return: Zero on success, otherwise an error number. 494 */ 495 static inline int ntb_mw_set_trans(struct ntb_dev *ntb, int idx, 496 dma_addr_t addr, resource_size_t size) 497 { 498 return ntb->ops->mw_set_trans(ntb, idx, addr, size); 499 } 500 501 /** 502 * ntb_mw_clear_trans() - clear the translation of a memory window 503 * @ntb: NTB device context. 504 * @idx: Memory window number. 505 * 506 * Clear the translation of a memory window. The peer may no longer access 507 * local memory through the window. 508 * 509 * Return: Zero on success, otherwise an error number. 510 */ 511 static inline int ntb_mw_clear_trans(struct ntb_dev *ntb, int idx) 512 { 513 if (!ntb->ops->mw_clear_trans) 514 return ntb->ops->mw_set_trans(ntb, idx, 0, 0); 515 516 return ntb->ops->mw_clear_trans(ntb, idx); 517 } 518 519 /** 520 * ntb_link_is_up() - get the current ntb link state 521 * @ntb: NTB device context. 522 * @speed: OUT - The link speed expressed as PCIe generation number. 523 * @width: OUT - The link width expressed as the number of PCIe lanes. 524 * 525 * Set the translation of a memory window. The peer may access local memory 526 * through the window starting at the address, up to the size. The address 527 * must be aligned to the alignment specified by ntb_mw_get_range(). The size 528 * must be aligned to the size alignment specified by ntb_mw_get_range(). 529 * 530 * Return: One if the link is up, zero if the link is down, otherwise a 531 * negative value indicating the error number. 532 */ 533 static inline int ntb_link_is_up(struct ntb_dev *ntb, 534 enum ntb_speed *speed, enum ntb_width *width) 535 { 536 return ntb->ops->link_is_up(ntb, speed, width); 537 } 538 539 /** 540 * ntb_link_enable() - enable the link on the secondary side of the ntb 541 * @ntb: NTB device context. 542 * @max_speed: The maximum link speed expressed as PCIe generation number. 543 * @max_width: The maximum link width expressed as the number of PCIe lanes. 544 * 545 * Enable the link on the secondary side of the ntb. This can only be done 546 * from the primary side of the ntb in primary or b2b topology. The ntb device 547 * should train the link to its maximum speed and width, or the requested speed 548 * and width, whichever is smaller, if supported. 549 * 550 * Return: Zero on success, otherwise an error number. 551 */ 552 static inline int ntb_link_enable(struct ntb_dev *ntb, 553 enum ntb_speed max_speed, 554 enum ntb_width max_width) 555 { 556 return ntb->ops->link_enable(ntb, max_speed, max_width); 557 } 558 559 /** 560 * ntb_link_disable() - disable the link on the secondary side of the ntb 561 * @ntb: NTB device context. 562 * 563 * Disable the link on the secondary side of the ntb. This can only be 564 * done from the primary side of the ntb in primary or b2b topology. The ntb 565 * device should disable the link. Returning from this call must indicate that 566 * a barrier has passed, though with no more writes may pass in either 567 * direction across the link, except if this call returns an error number. 568 * 569 * Return: Zero on success, otherwise an error number. 570 */ 571 static inline int ntb_link_disable(struct ntb_dev *ntb) 572 { 573 return ntb->ops->link_disable(ntb); 574 } 575 576 /** 577 * ntb_db_is_unsafe() - check if it is safe to use hardware doorbell 578 * @ntb: NTB device context. 579 * 580 * It is possible for some ntb hardware to be affected by errata. Hardware 581 * drivers can advise clients to avoid using doorbells. Clients may ignore 582 * this advice, though caution is recommended. 583 * 584 * Return: Zero if it is safe to use doorbells, or One if it is not safe. 585 */ 586 static inline int ntb_db_is_unsafe(struct ntb_dev *ntb) 587 { 588 if (!ntb->ops->db_is_unsafe) 589 return 0; 590 591 return ntb->ops->db_is_unsafe(ntb); 592 } 593 594 /** 595 * ntb_db_valid_mask() - get a mask of doorbell bits supported by the ntb 596 * @ntb: NTB device context. 597 * 598 * Hardware may support different number or arrangement of doorbell bits. 599 * 600 * Return: A mask of doorbell bits supported by the ntb. 601 */ 602 static inline u64 ntb_db_valid_mask(struct ntb_dev *ntb) 603 { 604 return ntb->ops->db_valid_mask(ntb); 605 } 606 607 /** 608 * ntb_db_vector_count() - get the number of doorbell interrupt vectors 609 * @ntb: NTB device context. 610 * 611 * Hardware may support different number of interrupt vectors. 612 * 613 * Return: The number of doorbell interrupt vectors. 614 */ 615 static inline int ntb_db_vector_count(struct ntb_dev *ntb) 616 { 617 if (!ntb->ops->db_vector_count) 618 return 1; 619 620 return ntb->ops->db_vector_count(ntb); 621 } 622 623 /** 624 * ntb_db_vector_mask() - get a mask of doorbell bits serviced by a vector 625 * @ntb: NTB device context. 626 * @vector: Doorbell vector number. 627 * 628 * Each interrupt vector may have a different number or arrangement of bits. 629 * 630 * Return: A mask of doorbell bits serviced by a vector. 631 */ 632 static inline u64 ntb_db_vector_mask(struct ntb_dev *ntb, int vector) 633 { 634 if (!ntb->ops->db_vector_mask) 635 return ntb_db_valid_mask(ntb); 636 637 return ntb->ops->db_vector_mask(ntb, vector); 638 } 639 640 /** 641 * ntb_db_read() - read the local doorbell register 642 * @ntb: NTB device context. 643 * 644 * Read the local doorbell register, and return the bits that are set. 645 * 646 * Return: The bits currently set in the local doorbell register. 647 */ 648 static inline u64 ntb_db_read(struct ntb_dev *ntb) 649 { 650 return ntb->ops->db_read(ntb); 651 } 652 653 /** 654 * ntb_db_set() - set bits in the local doorbell register 655 * @ntb: NTB device context. 656 * @db_bits: Doorbell bits to set. 657 * 658 * Set bits in the local doorbell register, which may generate a local doorbell 659 * interrupt. Bits that were already set must remain set. 660 * 661 * This is unusual, and hardware may not support it. 662 * 663 * Return: Zero on success, otherwise an error number. 664 */ 665 static inline int ntb_db_set(struct ntb_dev *ntb, u64 db_bits) 666 { 667 if (!ntb->ops->db_set) 668 return -EINVAL; 669 670 return ntb->ops->db_set(ntb, db_bits); 671 } 672 673 /** 674 * ntb_db_clear() - clear bits in the local doorbell register 675 * @ntb: NTB device context. 676 * @db_bits: Doorbell bits to clear. 677 * 678 * Clear bits in the local doorbell register, arming the bits for the next 679 * doorbell. 680 * 681 * Return: Zero on success, otherwise an error number. 682 */ 683 static inline int ntb_db_clear(struct ntb_dev *ntb, u64 db_bits) 684 { 685 return ntb->ops->db_clear(ntb, db_bits); 686 } 687 688 /** 689 * ntb_db_read_mask() - read the local doorbell mask 690 * @ntb: NTB device context. 691 * 692 * Read the local doorbell mask register, and return the bits that are set. 693 * 694 * This is unusual, though hardware is likely to support it. 695 * 696 * Return: The bits currently set in the local doorbell mask register. 697 */ 698 static inline u64 ntb_db_read_mask(struct ntb_dev *ntb) 699 { 700 if (!ntb->ops->db_read_mask) 701 return 0; 702 703 return ntb->ops->db_read_mask(ntb); 704 } 705 706 /** 707 * ntb_db_set_mask() - set bits in the local doorbell mask 708 * @ntb: NTB device context. 709 * @db_bits: Doorbell mask bits to set. 710 * 711 * Set bits in the local doorbell mask register, preventing doorbell interrupts 712 * from being generated for those doorbell bits. Bits that were already set 713 * must remain set. 714 * 715 * Return: Zero on success, otherwise an error number. 716 */ 717 static inline int ntb_db_set_mask(struct ntb_dev *ntb, u64 db_bits) 718 { 719 return ntb->ops->db_set_mask(ntb, db_bits); 720 } 721 722 /** 723 * ntb_db_clear_mask() - clear bits in the local doorbell mask 724 * @ntb: NTB device context. 725 * @db_bits: Doorbell bits to clear. 726 * 727 * Clear bits in the local doorbell mask register, allowing doorbell interrupts 728 * from being generated for those doorbell bits. If a doorbell bit is already 729 * set at the time the mask is cleared, and the corresponding mask bit is 730 * changed from set to clear, then the ntb driver must ensure that 731 * ntb_db_event() is called. If the hardware does not generate the interrupt 732 * on clearing the mask bit, then the driver must call ntb_db_event() anyway. 733 * 734 * Return: Zero on success, otherwise an error number. 735 */ 736 static inline int ntb_db_clear_mask(struct ntb_dev *ntb, u64 db_bits) 737 { 738 return ntb->ops->db_clear_mask(ntb, db_bits); 739 } 740 741 /** 742 * ntb_peer_db_addr() - address and size of the peer doorbell register 743 * @ntb: NTB device context. 744 * @db_addr: OUT - The address of the peer doorbell register. 745 * @db_size: OUT - The number of bytes to write the peer doorbell register. 746 * 747 * Return the address of the peer doorbell register. This may be used, for 748 * example, by drivers that offload memory copy operations to a dma engine. 749 * The drivers may wish to ring the peer doorbell at the completion of memory 750 * copy operations. For efficiency, and to simplify ordering of operations 751 * between the dma memory copies and the ringing doorbell, the driver may 752 * append one additional dma memory copy with the doorbell register as the 753 * destination, after the memory copy operations. 754 * 755 * Return: Zero on success, otherwise an error number. 756 */ 757 static inline int ntb_peer_db_addr(struct ntb_dev *ntb, 758 phys_addr_t *db_addr, 759 resource_size_t *db_size) 760 { 761 return ntb->ops->peer_db_addr(ntb, db_addr, db_size); 762 } 763 764 /** 765 * ntb_peer_db_read() - read the peer doorbell register 766 * @ntb: NTB device context. 767 * 768 * Read the peer doorbell register, and return the bits that are set. 769 * 770 * This is unusual, and hardware may not support it. 771 * 772 * Return: The bits currently set in the peer doorbell register. 773 */ 774 static inline u64 ntb_peer_db_read(struct ntb_dev *ntb) 775 { 776 if (!ntb->ops->peer_db_read) 777 return 0; 778 779 return ntb->ops->peer_db_read(ntb); 780 } 781 782 /** 783 * ntb_peer_db_set() - set bits in the peer doorbell register 784 * @ntb: NTB device context. 785 * @db_bits: Doorbell bits to set. 786 * 787 * Set bits in the peer doorbell register, which may generate a peer doorbell 788 * interrupt. Bits that were already set must remain set. 789 * 790 * Return: Zero on success, otherwise an error number. 791 */ 792 static inline int ntb_peer_db_set(struct ntb_dev *ntb, u64 db_bits) 793 { 794 return ntb->ops->peer_db_set(ntb, db_bits); 795 } 796 797 /** 798 * ntb_peer_db_clear() - clear bits in the local doorbell register 799 * @ntb: NTB device context. 800 * @db_bits: Doorbell bits to clear. 801 * 802 * Clear bits in the peer doorbell register, arming the bits for the next 803 * doorbell. 804 * 805 * This is unusual, and hardware may not support it. 806 * 807 * Return: Zero on success, otherwise an error number. 808 */ 809 static inline int ntb_peer_db_clear(struct ntb_dev *ntb, u64 db_bits) 810 { 811 if (!ntb->ops->db_clear) 812 return -EINVAL; 813 814 return ntb->ops->peer_db_clear(ntb, db_bits); 815 } 816 817 /** 818 * ntb_peer_db_read_mask() - read the peer doorbell mask 819 * @ntb: NTB device context. 820 * 821 * Read the peer doorbell mask register, and return the bits that are set. 822 * 823 * This is unusual, and hardware may not support it. 824 * 825 * Return: The bits currently set in the peer doorbell mask register. 826 */ 827 static inline u64 ntb_peer_db_read_mask(struct ntb_dev *ntb) 828 { 829 if (!ntb->ops->db_read_mask) 830 return 0; 831 832 return ntb->ops->peer_db_read_mask(ntb); 833 } 834 835 /** 836 * ntb_peer_db_set_mask() - set bits in the peer doorbell mask 837 * @ntb: NTB device context. 838 * @db_bits: Doorbell mask bits to set. 839 * 840 * Set bits in the peer doorbell mask register, preventing doorbell interrupts 841 * from being generated for those doorbell bits. Bits that were already set 842 * must remain set. 843 * 844 * This is unusual, and hardware may not support it. 845 * 846 * Return: Zero on success, otherwise an error number. 847 */ 848 static inline int ntb_peer_db_set_mask(struct ntb_dev *ntb, u64 db_bits) 849 { 850 if (!ntb->ops->db_set_mask) 851 return -EINVAL; 852 853 return ntb->ops->peer_db_set_mask(ntb, db_bits); 854 } 855 856 /** 857 * ntb_peer_db_clear_mask() - clear bits in the peer doorbell mask 858 * @ntb: NTB device context. 859 * @db_bits: Doorbell bits to clear. 860 * 861 * Clear bits in the peer doorbell mask register, allowing doorbell interrupts 862 * from being generated for those doorbell bits. If the hardware does not 863 * generate the interrupt on clearing the mask bit, then the driver should not 864 * implement this function! 865 * 866 * This is unusual, and hardware may not support it. 867 * 868 * Return: Zero on success, otherwise an error number. 869 */ 870 static inline int ntb_peer_db_clear_mask(struct ntb_dev *ntb, u64 db_bits) 871 { 872 if (!ntb->ops->db_clear_mask) 873 return -EINVAL; 874 875 return ntb->ops->peer_db_clear_mask(ntb, db_bits); 876 } 877 878 /** 879 * ntb_spad_is_unsafe() - check if it is safe to use the hardware scratchpads 880 * @ntb: NTB device context. 881 * 882 * It is possible for some ntb hardware to be affected by errata. Hardware 883 * drivers can advise clients to avoid using scratchpads. Clients may ignore 884 * this advice, though caution is recommended. 885 * 886 * Return: Zero if it is safe to use scratchpads, or One if it is not safe. 887 */ 888 static inline int ntb_spad_is_unsafe(struct ntb_dev *ntb) 889 { 890 if (!ntb->ops->spad_is_unsafe) 891 return 0; 892 893 return ntb->ops->spad_is_unsafe(ntb); 894 } 895 896 /** 897 * ntb_mw_count() - get the number of scratchpads 898 * @ntb: NTB device context. 899 * 900 * Hardware and topology may support a different number of scratchpads. 901 * 902 * Return: the number of scratchpads. 903 */ 904 static inline int ntb_spad_count(struct ntb_dev *ntb) 905 { 906 return ntb->ops->spad_count(ntb); 907 } 908 909 /** 910 * ntb_spad_read() - read the local scratchpad register 911 * @ntb: NTB device context. 912 * @idx: Scratchpad index. 913 * 914 * Read the local scratchpad register, and return the value. 915 * 916 * Return: The value of the local scratchpad register. 917 */ 918 static inline u32 ntb_spad_read(struct ntb_dev *ntb, int idx) 919 { 920 return ntb->ops->spad_read(ntb, idx); 921 } 922 923 /** 924 * ntb_spad_write() - write the local scratchpad register 925 * @ntb: NTB device context. 926 * @idx: Scratchpad index. 927 * @val: Scratchpad value. 928 * 929 * Write the value to the local scratchpad register. 930 * 931 * Return: Zero on success, otherwise an error number. 932 */ 933 static inline int ntb_spad_write(struct ntb_dev *ntb, int idx, u32 val) 934 { 935 return ntb->ops->spad_write(ntb, idx, val); 936 } 937 938 /** 939 * ntb_peer_spad_addr() - address of the peer scratchpad register 940 * @ntb: NTB device context. 941 * @idx: Scratchpad index. 942 * @spad_addr: OUT - The address of the peer scratchpad register. 943 * 944 * Return the address of the peer doorbell register. This may be used, for 945 * example, by drivers that offload memory copy operations to a dma engine. 946 * 947 * Return: Zero on success, otherwise an error number. 948 */ 949 static inline int ntb_peer_spad_addr(struct ntb_dev *ntb, int idx, 950 phys_addr_t *spad_addr) 951 { 952 return ntb->ops->peer_spad_addr(ntb, idx, spad_addr); 953 } 954 955 /** 956 * ntb_peer_spad_read() - read the peer scratchpad register 957 * @ntb: NTB device context. 958 * @idx: Scratchpad index. 959 * 960 * Read the peer scratchpad register, and return the value. 961 * 962 * Return: The value of the local scratchpad register. 963 */ 964 static inline u32 ntb_peer_spad_read(struct ntb_dev *ntb, int idx) 965 { 966 return ntb->ops->peer_spad_read(ntb, idx); 967 } 968 969 /** 970 * ntb_peer_spad_write() - write the peer scratchpad register 971 * @ntb: NTB device context. 972 * @idx: Scratchpad index. 973 * @val: Scratchpad value. 974 * 975 * Write the value to the peer scratchpad register. 976 * 977 * Return: Zero on success, otherwise an error number. 978 */ 979 static inline int ntb_peer_spad_write(struct ntb_dev *ntb, int idx, u32 val) 980 { 981 return ntb->ops->peer_spad_write(ntb, idx, val); 982 } 983 984 #endif 985