1 /* SPDX-License-Identifier: (GPL-2.0-only OR BSD-3-Clause) */ 2 /* QLogic qed NIC Driver 3 * Copyright (c) 2015-2017 QLogic Corporation 4 * Copyright (c) 2019-2020 Marvell International Ltd. 5 */ 6 7 #ifndef _QED_CHAIN_H 8 #define _QED_CHAIN_H 9 10 #include <linux/types.h> 11 #include <asm/byteorder.h> 12 #include <linux/kernel.h> 13 #include <linux/list.h> 14 #include <linux/sizes.h> 15 #include <linux/slab.h> 16 #include <linux/qed/common_hsi.h> 17 18 enum qed_chain_mode { 19 /* Each Page contains a next pointer at its end */ 20 QED_CHAIN_MODE_NEXT_PTR, 21 22 /* Chain is a single page (next ptr) is not required */ 23 QED_CHAIN_MODE_SINGLE, 24 25 /* Page pointers are located in a side list */ 26 QED_CHAIN_MODE_PBL, 27 }; 28 29 enum qed_chain_use_mode { 30 QED_CHAIN_USE_TO_PRODUCE, /* Chain starts empty */ 31 QED_CHAIN_USE_TO_CONSUME, /* Chain starts full */ 32 QED_CHAIN_USE_TO_CONSUME_PRODUCE, /* Chain starts empty */ 33 }; 34 35 enum qed_chain_cnt_type { 36 /* The chain's size/prod/cons are kept in 16-bit variables */ 37 QED_CHAIN_CNT_TYPE_U16, 38 39 /* The chain's size/prod/cons are kept in 32-bit variables */ 40 QED_CHAIN_CNT_TYPE_U32, 41 }; 42 43 struct qed_chain_next { 44 struct regpair next_phys; 45 void *next_virt; 46 }; 47 48 struct qed_chain_pbl_u16 { 49 u16 prod_page_idx; 50 u16 cons_page_idx; 51 }; 52 53 struct qed_chain_pbl_u32 { 54 u32 prod_page_idx; 55 u32 cons_page_idx; 56 }; 57 58 struct qed_chain_u16 { 59 /* Cyclic index of next element to produce/consume */ 60 u16 prod_idx; 61 u16 cons_idx; 62 }; 63 64 struct qed_chain_u32 { 65 /* Cyclic index of next element to produce/consume */ 66 u32 prod_idx; 67 u32 cons_idx; 68 }; 69 70 struct addr_tbl_entry { 71 void *virt_addr; 72 dma_addr_t dma_map; 73 }; 74 75 struct qed_chain { 76 /* Fastpath portion of the chain - required for commands such 77 * as produce / consume. 78 */ 79 80 /* Point to next element to produce/consume */ 81 void *p_prod_elem; 82 void *p_cons_elem; 83 84 /* Fastpath portions of the PBL [if exists] */ 85 86 struct { 87 /* Table for keeping the virtual and physical addresses of the 88 * chain pages, respectively to the physical addresses 89 * in the pbl table. 90 */ 91 struct addr_tbl_entry *pp_addr_tbl; 92 93 union { 94 struct qed_chain_pbl_u16 u16; 95 struct qed_chain_pbl_u32 u32; 96 } c; 97 } pbl; 98 99 union { 100 struct qed_chain_u16 chain16; 101 struct qed_chain_u32 chain32; 102 } u; 103 104 /* Capacity counts only usable elements */ 105 u32 capacity; 106 u32 page_cnt; 107 108 enum qed_chain_mode mode; 109 110 /* Elements information for fast calculations */ 111 u16 elem_per_page; 112 u16 elem_per_page_mask; 113 u16 elem_size; 114 u16 next_page_mask; 115 u16 usable_per_page; 116 u8 elem_unusable; 117 118 enum qed_chain_cnt_type cnt_type; 119 120 /* Slowpath of the chain - required for initialization and destruction, 121 * but isn't involved in regular functionality. 122 */ 123 124 u32 page_size; 125 126 /* Base address of a pre-allocated buffer for pbl */ 127 struct { 128 __le64 *table_virt; 129 dma_addr_t table_phys; 130 size_t table_size; 131 } pbl_sp; 132 133 /* Address of first page of the chain - the address is required 134 * for fastpath operation [consume/produce] but only for the SINGLE 135 * flavour which isn't considered fastpath [== SPQ]. 136 */ 137 void *p_virt_addr; 138 dma_addr_t p_phys_addr; 139 140 /* Total number of elements [for entire chain] */ 141 u32 size; 142 143 enum qed_chain_use_mode intended_use; 144 145 bool b_external_pbl; 146 }; 147 148 struct qed_chain_init_params { 149 enum qed_chain_mode mode; 150 enum qed_chain_use_mode intended_use; 151 enum qed_chain_cnt_type cnt_type; 152 153 u32 page_size; 154 u32 num_elems; 155 size_t elem_size; 156 157 void *ext_pbl_virt; 158 dma_addr_t ext_pbl_phys; 159 }; 160 161 #define QED_CHAIN_PAGE_SIZE SZ_4K 162 163 #define ELEMS_PER_PAGE(elem_size, page_size) \ 164 ((page_size) / (elem_size)) 165 166 #define UNUSABLE_ELEMS_PER_PAGE(elem_size, mode) \ 167 (((mode) == QED_CHAIN_MODE_NEXT_PTR) ? \ 168 (u8)(1 + ((sizeof(struct qed_chain_next) - 1) / (elem_size))) : \ 169 0) 170 171 #define USABLE_ELEMS_PER_PAGE(elem_size, page_size, mode) \ 172 ((u32)(ELEMS_PER_PAGE((elem_size), (page_size)) - \ 173 UNUSABLE_ELEMS_PER_PAGE((elem_size), (mode)))) 174 175 #define QED_CHAIN_PAGE_CNT(elem_cnt, elem_size, page_size, mode) \ 176 DIV_ROUND_UP((elem_cnt), \ 177 USABLE_ELEMS_PER_PAGE((elem_size), (page_size), (mode))) 178 179 #define is_chain_u16(p) \ 180 ((p)->cnt_type == QED_CHAIN_CNT_TYPE_U16) 181 #define is_chain_u32(p) \ 182 ((p)->cnt_type == QED_CHAIN_CNT_TYPE_U32) 183 184 /* Accessors */ 185 186 static inline u16 qed_chain_get_prod_idx(const struct qed_chain *chain) 187 { 188 return chain->u.chain16.prod_idx; 189 } 190 191 static inline u16 qed_chain_get_cons_idx(const struct qed_chain *chain) 192 { 193 return chain->u.chain16.cons_idx; 194 } 195 196 static inline u32 qed_chain_get_prod_idx_u32(const struct qed_chain *chain) 197 { 198 return chain->u.chain32.prod_idx; 199 } 200 201 static inline u32 qed_chain_get_cons_idx_u32(const struct qed_chain *chain) 202 { 203 return chain->u.chain32.cons_idx; 204 } 205 206 static inline u16 qed_chain_get_elem_used(const struct qed_chain *chain) 207 { 208 u32 prod = qed_chain_get_prod_idx(chain); 209 u32 cons = qed_chain_get_cons_idx(chain); 210 u16 elem_per_page = chain->elem_per_page; 211 u16 used; 212 213 if (prod < cons) 214 prod += (u32)U16_MAX + 1; 215 216 used = (u16)(prod - cons); 217 if (chain->mode == QED_CHAIN_MODE_NEXT_PTR) 218 used -= (u16)(prod / elem_per_page - cons / elem_per_page); 219 220 return used; 221 } 222 223 static inline u16 qed_chain_get_elem_left(const struct qed_chain *chain) 224 { 225 return (u16)(chain->capacity - qed_chain_get_elem_used(chain)); 226 } 227 228 static inline u32 qed_chain_get_elem_used_u32(const struct qed_chain *chain) 229 { 230 u64 prod = qed_chain_get_prod_idx_u32(chain); 231 u64 cons = qed_chain_get_cons_idx_u32(chain); 232 u16 elem_per_page = chain->elem_per_page; 233 u32 used; 234 235 if (prod < cons) 236 prod += (u64)U32_MAX + 1; 237 238 used = (u32)(prod - cons); 239 if (chain->mode == QED_CHAIN_MODE_NEXT_PTR) 240 used -= (u32)(prod / elem_per_page - cons / elem_per_page); 241 242 return used; 243 } 244 245 static inline u32 qed_chain_get_elem_left_u32(const struct qed_chain *chain) 246 { 247 return chain->capacity - qed_chain_get_elem_used_u32(chain); 248 } 249 250 static inline u16 qed_chain_get_usable_per_page(const struct qed_chain *chain) 251 { 252 return chain->usable_per_page; 253 } 254 255 static inline u8 qed_chain_get_unusable_per_page(const struct qed_chain *chain) 256 { 257 return chain->elem_unusable; 258 } 259 260 static inline u32 qed_chain_get_page_cnt(const struct qed_chain *chain) 261 { 262 return chain->page_cnt; 263 } 264 265 static inline dma_addr_t qed_chain_get_pbl_phys(const struct qed_chain *chain) 266 { 267 return chain->pbl_sp.table_phys; 268 } 269 270 /** 271 * @brief qed_chain_advance_page - 272 * 273 * Advance the next element across pages for a linked chain 274 * 275 * @param p_chain 276 * @param p_next_elem 277 * @param idx_to_inc 278 * @param page_to_inc 279 */ 280 static inline void 281 qed_chain_advance_page(struct qed_chain *p_chain, 282 void **p_next_elem, void *idx_to_inc, void *page_to_inc) 283 { 284 struct qed_chain_next *p_next = NULL; 285 u32 page_index = 0; 286 287 switch (p_chain->mode) { 288 case QED_CHAIN_MODE_NEXT_PTR: 289 p_next = *p_next_elem; 290 *p_next_elem = p_next->next_virt; 291 if (is_chain_u16(p_chain)) 292 *(u16 *)idx_to_inc += p_chain->elem_unusable; 293 else 294 *(u32 *)idx_to_inc += p_chain->elem_unusable; 295 break; 296 case QED_CHAIN_MODE_SINGLE: 297 *p_next_elem = p_chain->p_virt_addr; 298 break; 299 300 case QED_CHAIN_MODE_PBL: 301 if (is_chain_u16(p_chain)) { 302 if (++(*(u16 *)page_to_inc) == p_chain->page_cnt) 303 *(u16 *)page_to_inc = 0; 304 page_index = *(u16 *)page_to_inc; 305 } else { 306 if (++(*(u32 *)page_to_inc) == p_chain->page_cnt) 307 *(u32 *)page_to_inc = 0; 308 page_index = *(u32 *)page_to_inc; 309 } 310 *p_next_elem = p_chain->pbl.pp_addr_tbl[page_index].virt_addr; 311 } 312 } 313 314 #define is_unusable_idx(p, idx) \ 315 (((p)->u.chain16.idx & (p)->elem_per_page_mask) == (p)->usable_per_page) 316 317 #define is_unusable_idx_u32(p, idx) \ 318 (((p)->u.chain32.idx & (p)->elem_per_page_mask) == (p)->usable_per_page) 319 #define is_unusable_next_idx(p, idx) \ 320 ((((p)->u.chain16.idx + 1) & (p)->elem_per_page_mask) == \ 321 (p)->usable_per_page) 322 323 #define is_unusable_next_idx_u32(p, idx) \ 324 ((((p)->u.chain32.idx + 1) & (p)->elem_per_page_mask) == \ 325 (p)->usable_per_page) 326 327 #define test_and_skip(p, idx) \ 328 do { \ 329 if (is_chain_u16(p)) { \ 330 if (is_unusable_idx(p, idx)) \ 331 (p)->u.chain16.idx += (p)->elem_unusable; \ 332 } else { \ 333 if (is_unusable_idx_u32(p, idx)) \ 334 (p)->u.chain32.idx += (p)->elem_unusable; \ 335 } \ 336 } while (0) 337 338 /** 339 * @brief qed_chain_return_produced - 340 * 341 * A chain in which the driver "Produces" elements should use this API 342 * to indicate previous produced elements are now consumed. 343 * 344 * @param p_chain 345 */ 346 static inline void qed_chain_return_produced(struct qed_chain *p_chain) 347 { 348 if (is_chain_u16(p_chain)) 349 p_chain->u.chain16.cons_idx++; 350 else 351 p_chain->u.chain32.cons_idx++; 352 test_and_skip(p_chain, cons_idx); 353 } 354 355 /** 356 * @brief qed_chain_produce - 357 * 358 * A chain in which the driver "Produces" elements should use this to get 359 * a pointer to the next element which can be "Produced". It's driver 360 * responsibility to validate that the chain has room for new element. 361 * 362 * @param p_chain 363 * 364 * @return void*, a pointer to next element 365 */ 366 static inline void *qed_chain_produce(struct qed_chain *p_chain) 367 { 368 void *p_ret = NULL, *p_prod_idx, *p_prod_page_idx; 369 370 if (is_chain_u16(p_chain)) { 371 if ((p_chain->u.chain16.prod_idx & 372 p_chain->elem_per_page_mask) == p_chain->next_page_mask) { 373 p_prod_idx = &p_chain->u.chain16.prod_idx; 374 p_prod_page_idx = &p_chain->pbl.c.u16.prod_page_idx; 375 qed_chain_advance_page(p_chain, &p_chain->p_prod_elem, 376 p_prod_idx, p_prod_page_idx); 377 } 378 p_chain->u.chain16.prod_idx++; 379 } else { 380 if ((p_chain->u.chain32.prod_idx & 381 p_chain->elem_per_page_mask) == p_chain->next_page_mask) { 382 p_prod_idx = &p_chain->u.chain32.prod_idx; 383 p_prod_page_idx = &p_chain->pbl.c.u32.prod_page_idx; 384 qed_chain_advance_page(p_chain, &p_chain->p_prod_elem, 385 p_prod_idx, p_prod_page_idx); 386 } 387 p_chain->u.chain32.prod_idx++; 388 } 389 390 p_ret = p_chain->p_prod_elem; 391 p_chain->p_prod_elem = (void *)(((u8 *)p_chain->p_prod_elem) + 392 p_chain->elem_size); 393 394 return p_ret; 395 } 396 397 /** 398 * @brief qed_chain_get_capacity - 399 * 400 * Get the maximum number of BDs in chain 401 * 402 * @param p_chain 403 * @param num 404 * 405 * @return number of unusable BDs 406 */ 407 static inline u32 qed_chain_get_capacity(struct qed_chain *p_chain) 408 { 409 return p_chain->capacity; 410 } 411 412 /** 413 * @brief qed_chain_recycle_consumed - 414 * 415 * Returns an element which was previously consumed; 416 * Increments producers so they could be written to FW. 417 * 418 * @param p_chain 419 */ 420 static inline void qed_chain_recycle_consumed(struct qed_chain *p_chain) 421 { 422 test_and_skip(p_chain, prod_idx); 423 if (is_chain_u16(p_chain)) 424 p_chain->u.chain16.prod_idx++; 425 else 426 p_chain->u.chain32.prod_idx++; 427 } 428 429 /** 430 * @brief qed_chain_consume - 431 * 432 * A Chain in which the driver utilizes data written by a different source 433 * (i.e., FW) should use this to access passed buffers. 434 * 435 * @param p_chain 436 * 437 * @return void*, a pointer to the next buffer written 438 */ 439 static inline void *qed_chain_consume(struct qed_chain *p_chain) 440 { 441 void *p_ret = NULL, *p_cons_idx, *p_cons_page_idx; 442 443 if (is_chain_u16(p_chain)) { 444 if ((p_chain->u.chain16.cons_idx & 445 p_chain->elem_per_page_mask) == p_chain->next_page_mask) { 446 p_cons_idx = &p_chain->u.chain16.cons_idx; 447 p_cons_page_idx = &p_chain->pbl.c.u16.cons_page_idx; 448 qed_chain_advance_page(p_chain, &p_chain->p_cons_elem, 449 p_cons_idx, p_cons_page_idx); 450 } 451 p_chain->u.chain16.cons_idx++; 452 } else { 453 if ((p_chain->u.chain32.cons_idx & 454 p_chain->elem_per_page_mask) == p_chain->next_page_mask) { 455 p_cons_idx = &p_chain->u.chain32.cons_idx; 456 p_cons_page_idx = &p_chain->pbl.c.u32.cons_page_idx; 457 qed_chain_advance_page(p_chain, &p_chain->p_cons_elem, 458 p_cons_idx, p_cons_page_idx); 459 } 460 p_chain->u.chain32.cons_idx++; 461 } 462 463 p_ret = p_chain->p_cons_elem; 464 p_chain->p_cons_elem = (void *)(((u8 *)p_chain->p_cons_elem) + 465 p_chain->elem_size); 466 467 return p_ret; 468 } 469 470 /** 471 * @brief qed_chain_reset - Resets the chain to its start state 472 * 473 * @param p_chain pointer to a previously allocated chain 474 */ 475 static inline void qed_chain_reset(struct qed_chain *p_chain) 476 { 477 u32 i; 478 479 if (is_chain_u16(p_chain)) { 480 p_chain->u.chain16.prod_idx = 0; 481 p_chain->u.chain16.cons_idx = 0; 482 } else { 483 p_chain->u.chain32.prod_idx = 0; 484 p_chain->u.chain32.cons_idx = 0; 485 } 486 p_chain->p_cons_elem = p_chain->p_virt_addr; 487 p_chain->p_prod_elem = p_chain->p_virt_addr; 488 489 if (p_chain->mode == QED_CHAIN_MODE_PBL) { 490 /* Use (page_cnt - 1) as a reset value for the prod/cons page's 491 * indices, to avoid unnecessary page advancing on the first 492 * call to qed_chain_produce/consume. Instead, the indices 493 * will be advanced to page_cnt and then will be wrapped to 0. 494 */ 495 u32 reset_val = p_chain->page_cnt - 1; 496 497 if (is_chain_u16(p_chain)) { 498 p_chain->pbl.c.u16.prod_page_idx = (u16)reset_val; 499 p_chain->pbl.c.u16.cons_page_idx = (u16)reset_val; 500 } else { 501 p_chain->pbl.c.u32.prod_page_idx = reset_val; 502 p_chain->pbl.c.u32.cons_page_idx = reset_val; 503 } 504 } 505 506 switch (p_chain->intended_use) { 507 case QED_CHAIN_USE_TO_CONSUME: 508 /* produce empty elements */ 509 for (i = 0; i < p_chain->capacity; i++) 510 qed_chain_recycle_consumed(p_chain); 511 break; 512 513 case QED_CHAIN_USE_TO_CONSUME_PRODUCE: 514 case QED_CHAIN_USE_TO_PRODUCE: 515 default: 516 /* Do nothing */ 517 break; 518 } 519 } 520 521 /** 522 * @brief qed_chain_get_last_elem - 523 * 524 * Returns a pointer to the last element of the chain 525 * 526 * @param p_chain 527 * 528 * @return void* 529 */ 530 static inline void *qed_chain_get_last_elem(struct qed_chain *p_chain) 531 { 532 struct qed_chain_next *p_next = NULL; 533 void *p_virt_addr = NULL; 534 u32 size, last_page_idx; 535 536 if (!p_chain->p_virt_addr) 537 goto out; 538 539 switch (p_chain->mode) { 540 case QED_CHAIN_MODE_NEXT_PTR: 541 size = p_chain->elem_size * p_chain->usable_per_page; 542 p_virt_addr = p_chain->p_virt_addr; 543 p_next = (struct qed_chain_next *)((u8 *)p_virt_addr + size); 544 while (p_next->next_virt != p_chain->p_virt_addr) { 545 p_virt_addr = p_next->next_virt; 546 p_next = (struct qed_chain_next *)((u8 *)p_virt_addr + 547 size); 548 } 549 break; 550 case QED_CHAIN_MODE_SINGLE: 551 p_virt_addr = p_chain->p_virt_addr; 552 break; 553 case QED_CHAIN_MODE_PBL: 554 last_page_idx = p_chain->page_cnt - 1; 555 p_virt_addr = p_chain->pbl.pp_addr_tbl[last_page_idx].virt_addr; 556 break; 557 } 558 /* p_virt_addr points at this stage to the last page of the chain */ 559 size = p_chain->elem_size * (p_chain->usable_per_page - 1); 560 p_virt_addr = (u8 *)p_virt_addr + size; 561 out: 562 return p_virt_addr; 563 } 564 565 /** 566 * @brief qed_chain_set_prod - sets the prod to the given value 567 * 568 * @param prod_idx 569 * @param p_prod_elem 570 */ 571 static inline void qed_chain_set_prod(struct qed_chain *p_chain, 572 u32 prod_idx, void *p_prod_elem) 573 { 574 if (p_chain->mode == QED_CHAIN_MODE_PBL) { 575 u32 cur_prod, page_mask, page_cnt, page_diff; 576 577 cur_prod = is_chain_u16(p_chain) ? p_chain->u.chain16.prod_idx : 578 p_chain->u.chain32.prod_idx; 579 580 /* Assume that number of elements in a page is power of 2 */ 581 page_mask = ~p_chain->elem_per_page_mask; 582 583 /* Use "cur_prod - 1" and "prod_idx - 1" since producer index 584 * reaches the first element of next page before the page index 585 * is incremented. See qed_chain_produce(). 586 * Index wrap around is not a problem because the difference 587 * between current and given producer indices is always 588 * positive and lower than the chain's capacity. 589 */ 590 page_diff = (((cur_prod - 1) & page_mask) - 591 ((prod_idx - 1) & page_mask)) / 592 p_chain->elem_per_page; 593 594 page_cnt = qed_chain_get_page_cnt(p_chain); 595 if (is_chain_u16(p_chain)) 596 p_chain->pbl.c.u16.prod_page_idx = 597 (p_chain->pbl.c.u16.prod_page_idx - 598 page_diff + page_cnt) % page_cnt; 599 else 600 p_chain->pbl.c.u32.prod_page_idx = 601 (p_chain->pbl.c.u32.prod_page_idx - 602 page_diff + page_cnt) % page_cnt; 603 } 604 605 if (is_chain_u16(p_chain)) 606 p_chain->u.chain16.prod_idx = (u16) prod_idx; 607 else 608 p_chain->u.chain32.prod_idx = prod_idx; 609 p_chain->p_prod_elem = p_prod_elem; 610 } 611 612 /** 613 * @brief qed_chain_pbl_zero_mem - set chain memory to 0 614 * 615 * @param p_chain 616 */ 617 static inline void qed_chain_pbl_zero_mem(struct qed_chain *p_chain) 618 { 619 u32 i, page_cnt; 620 621 if (p_chain->mode != QED_CHAIN_MODE_PBL) 622 return; 623 624 page_cnt = qed_chain_get_page_cnt(p_chain); 625 626 for (i = 0; i < page_cnt; i++) 627 memset(p_chain->pbl.pp_addr_tbl[i].virt_addr, 0, 628 p_chain->page_size); 629 } 630 631 #endif 632