include/linux/qed/qed_chain.h

   1 /* QLogic qed NIC Driver
   2  * Copyright (c) 2015-2017  QLogic Corporation
   3  *
   4  * This software is available to you under a choice of one of two
   5  * licenses.  You may choose to be licensed under the terms of the GNU
   6  * General Public License (GPL) Version 2, available from the file
   7  * COPYING in the main directory of this source tree, or the
   8  * OpenIB.org BSD license below:
   9  *
  10  *     Redistribution and use in source and binary forms, with or
  11  *     without modification, are permitted provided that the following
  12  *     conditions are met:
  13  *
  14  *      - Redistributions of source code must retain the above
  15  *        copyright notice, this list of conditions and the following
  16  *        disclaimer.
  17  *
  18  *      - Redistributions in binary form must reproduce the above
  19  *        copyright notice, this list of conditions and the following
  20  *        disclaimer in the documentation and /or other materials
  21  *        provided with the distribution.
  22  *
  23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  30  * SOFTWARE.
  31  */
  32
  33 #ifndef _QED_CHAIN_H
  34 #define _QED_CHAIN_H
  35
  36 #include <linux/types.h>
  37 #include <asm/byteorder.h>
  38 #include <linux/kernel.h>
  39 #include <linux/list.h>
  40 #include <linux/slab.h>
  41 #include <linux/qed/common_hsi.h>
  42
  43 enum qed_chain_mode {
  44         /* Each Page contains a next pointer at its end */
  45         QED_CHAIN_MODE_NEXT_PTR,
  46
  47         /* Chain is a single page (next ptr) is unrequired */
  48         QED_CHAIN_MODE_SINGLE,
  49
  50         /* Page pointers are located in a side list */
  51         QED_CHAIN_MODE_PBL,
  52 };
  53
  54 enum qed_chain_use_mode {
  55         QED_CHAIN_USE_TO_PRODUCE,               /* Chain starts empty */
  56         QED_CHAIN_USE_TO_CONSUME,               /* Chain starts full */
  57         QED_CHAIN_USE_TO_CONSUME_PRODUCE,       /* Chain starts empty */
  58 };
  59
  60 enum qed_chain_cnt_type {
  61         /* The chain's size/prod/cons are kept in 16-bit variables */
  62         QED_CHAIN_CNT_TYPE_U16,
  63
  64         /* The chain's size/prod/cons are kept in 32-bit variables  */
  65         QED_CHAIN_CNT_TYPE_U32,
  66 };
  67
  68 struct qed_chain_next {
  69         struct regpair  next_phys;
  70         void            *next_virt;
  71 };
  72
  73 struct qed_chain_pbl_u16 {
  74         u16 prod_page_idx;
  75         u16 cons_page_idx;
  76 };
  77
  78 struct qed_chain_pbl_u32 {
  79         u32 prod_page_idx;
  80         u32 cons_page_idx;
  81 };
  82
  83 struct qed_chain_ext_pbl {
  84         dma_addr_t p_pbl_phys;
  85         void *p_pbl_virt;
  86 };
  87
  88 struct qed_chain_u16 {
  89         /* Cyclic index of next element to produce/consme */
  90         u16 prod_idx;
  91         u16 cons_idx;
  92 };
  93
  94 struct qed_chain_u32 {
  95         /* Cyclic index of next element to produce/consme */
  96         u32 prod_idx;
  97         u32 cons_idx;
  98 };
  99
 100 struct addr_tbl_entry {
 101         void *virt_addr;
 102         dma_addr_t dma_map;
 103 };
 104
 105 struct qed_chain {
 106         /* fastpath portion of the chain - required for commands such
 107          * as produce / consume.
 108          */
 109         /* Point to next element to produce/consume */
 110         void *p_prod_elem;
 111         void *p_cons_elem;
 112
 113         /* Fastpath portions of the PBL [if exists] */
 114         struct {
 115                 /* Table for keeping the virtual and physical addresses of the
 116                  * chain pages, respectively to the physical addresses
 117                  * in the pbl table.
 118                  */
 119                 struct addr_tbl_entry *pp_addr_tbl;
 120
 121                 union {
 122                         struct qed_chain_pbl_u16 u16;
 123                         struct qed_chain_pbl_u32 u32;
 124                 } c;
 125         } pbl;
 126
 127         union {
 128                 struct qed_chain_u16 chain16;
 129                 struct qed_chain_u32 chain32;
 130         } u;
 131
 132         /* Capacity counts only usable elements */
 133         u32 capacity;
 134         u32 page_cnt;
 135
 136         enum qed_chain_mode mode;
 137
 138         /* Elements information for fast calculations */
 139         u16 elem_per_page;
 140         u16 elem_per_page_mask;
 141         u16 elem_size;
 142         u16 next_page_mask;
 143         u16 usable_per_page;
 144         u8 elem_unusable;
 145
 146         u8 cnt_type;
 147
 148         /* Slowpath of the chain - required for initialization and destruction,
 149          * but isn't involved in regular functionality.
 150          */
 151
 152         /* Base address of a pre-allocated buffer for pbl */
 153         struct {
 154                 dma_addr_t p_phys_table;
 155                 void *p_virt_table;
 156         } pbl_sp;
 157
 158         /* Address of first page of the chain - the address is required
 159          * for fastpath operation [consume/produce] but only for the the SINGLE
 160          * flavour which isn't considered fastpath [== SPQ].
 161          */
 162         void *p_virt_addr;
 163         dma_addr_t p_phys_addr;
 164
 165         /* Total number of elements [for entire chain] */
 166         u32 size;
 167
 168         u8 intended_use;
 169
 170         bool b_external_pbl;
 171 };
 172
 173 #define QED_CHAIN_PBL_ENTRY_SIZE        (8)
 174 #define QED_CHAIN_PAGE_SIZE             (0x1000)
 175 #define ELEMS_PER_PAGE(elem_size)       (QED_CHAIN_PAGE_SIZE / (elem_size))
 176
 177 #define UNUSABLE_ELEMS_PER_PAGE(elem_size, mode)         \
 178         (((mode) == QED_CHAIN_MODE_NEXT_PTR) ?           \
 179          (u8)(1 + ((sizeof(struct qed_chain_next) - 1) / \
 180                    (elem_size))) : 0)
 181
 182 #define USABLE_ELEMS_PER_PAGE(elem_size, mode) \
 183         ((u32)(ELEMS_PER_PAGE(elem_size) -     \
 184                UNUSABLE_ELEMS_PER_PAGE(elem_size, mode)))
 185
 186 #define QED_CHAIN_PAGE_CNT(elem_cnt, elem_size, mode) \
 187         DIV_ROUND_UP(elem_cnt, USABLE_ELEMS_PER_PAGE(elem_size, mode))
 188
 189 #define is_chain_u16(p) ((p)->cnt_type == QED_CHAIN_CNT_TYPE_U16)
 190 #define is_chain_u32(p) ((p)->cnt_type == QED_CHAIN_CNT_TYPE_U32)
 191
 192 /* Accessors */
 193 static inline u16 qed_chain_get_prod_idx(struct qed_chain *p_chain)
 194 {
 195         return p_chain->u.chain16.prod_idx;
 196 }
 197
 198 static inline u16 qed_chain_get_cons_idx(struct qed_chain *p_chain)
 199 {
 200         return p_chain->u.chain16.cons_idx;
 201 }
 202
 203 static inline u32 qed_chain_get_cons_idx_u32(struct qed_chain *p_chain)
 204 {
 205         return p_chain->u.chain32.cons_idx;
 206 }
 207
 208 static inline u16 qed_chain_get_elem_left(struct qed_chain *p_chain)
 209 {
 210         u16 elem_per_page = p_chain->elem_per_page;
 211         u32 prod = p_chain->u.chain16.prod_idx;
 212         u32 cons = p_chain->u.chain16.cons_idx;
 213         u16 used;
 214
 215         if (prod < cons)
 216                 prod += (u32)U16_MAX + 1;
 217
 218         used = (u16)(prod - cons);
 219         if (p_chain->mode == QED_CHAIN_MODE_NEXT_PTR)
 220                 used -= prod / elem_per_page - cons / elem_per_page;
 221
 222         return (u16)(p_chain->capacity - used);
 223 }
 224
 225 static inline u32 qed_chain_get_elem_left_u32(struct qed_chain *p_chain)
 226 {
 227         u16 elem_per_page = p_chain->elem_per_page;
 228         u64 prod = p_chain->u.chain32.prod_idx;
 229         u64 cons = p_chain->u.chain32.cons_idx;
 230         u32 used;
 231
 232         if (prod < cons)
 233                 prod += (u64)U32_MAX + 1;
 234
 235         used = (u32)(prod - cons);
 236         if (p_chain->mode == QED_CHAIN_MODE_NEXT_PTR)
 237                 used -= (u32)(prod / elem_per_page - cons / elem_per_page);
 238
 239         return p_chain->capacity - used;
 240 }
 241
 242 static inline u16 qed_chain_get_usable_per_page(struct qed_chain *p_chain)
 243 {
 244         return p_chain->usable_per_page;
 245 }
 246
 247 static inline u8 qed_chain_get_unusable_per_page(struct qed_chain *p_chain)
 248 {
 249         return p_chain->elem_unusable;
 250 }
 251
 252 static inline u32 qed_chain_get_page_cnt(struct qed_chain *p_chain)
 253 {
 254         return p_chain->page_cnt;
 255 }
 256
 257 static inline dma_addr_t qed_chain_get_pbl_phys(struct qed_chain *p_chain)
 258 {
 259         return p_chain->pbl_sp.p_phys_table;
 260 }
 261
 262 /**
 263  * @brief qed_chain_advance_page -
 264  *
 265  * Advance the next element accros pages for a linked chain
 266  *
 267  * @param p_chain
 268  * @param p_next_elem
 269  * @param idx_to_inc
 270  * @param page_to_inc
 271  */
 272 static inline void
 273 qed_chain_advance_page(struct qed_chain *p_chain,
 274                        void **p_next_elem, void *idx_to_inc, void *page_to_inc)
 275 {
 276         struct qed_chain_next *p_next = NULL;
 277         u32 page_index = 0;
 278
 279         switch (p_chain->mode) {
 280         case QED_CHAIN_MODE_NEXT_PTR:
 281                 p_next = *p_next_elem;
 282                 *p_next_elem = p_next->next_virt;
 283                 if (is_chain_u16(p_chain))
 284                         *(u16 *)idx_to_inc += p_chain->elem_unusable;
 285                 else
 286                         *(u32 *)idx_to_inc += p_chain->elem_unusable;
 287                 break;
 288         case QED_CHAIN_MODE_SINGLE:
 289                 *p_next_elem = p_chain->p_virt_addr;
 290                 break;
 291
 292         case QED_CHAIN_MODE_PBL:
 293                 if (is_chain_u16(p_chain)) {
 294                         if (++(*(u16 *)page_to_inc) == p_chain->page_cnt)
 295                                 *(u16 *)page_to_inc = 0;
 296                         page_index = *(u16 *)page_to_inc;
 297                 } else {
 298                         if (++(*(u32 *)page_to_inc) == p_chain->page_cnt)
 299                                 *(u32 *)page_to_inc = 0;
 300                         page_index = *(u32 *)page_to_inc;
 301                 }
 302                 *p_next_elem = p_chain->pbl.pp_addr_tbl[page_index].virt_addr;
 303         }
 304 }
 305
 306 #define is_unusable_idx(p, idx) \
 307         (((p)->u.chain16.idx & (p)->elem_per_page_mask) == (p)->usable_per_page)
 308
 309 #define is_unusable_idx_u32(p, idx) \
 310         (((p)->u.chain32.idx & (p)->elem_per_page_mask) == (p)->usable_per_page)
 311 #define is_unusable_next_idx(p, idx)                             \
 312         ((((p)->u.chain16.idx + 1) & (p)->elem_per_page_mask) == \
 313          (p)->usable_per_page)
 314
 315 #define is_unusable_next_idx_u32(p, idx)                         \
 316         ((((p)->u.chain32.idx + 1) & (p)->elem_per_page_mask) == \
 317          (p)->usable_per_page)
 318
 319 #define test_and_skip(p, idx)                                              \
 320         do {                                            \
 321                 if (is_chain_u16(p)) {                                     \
 322                         if (is_unusable_idx(p, idx))                       \
 323                                 (p)->u.chain16.idx += (p)->elem_unusable;  \
 324                 } else {                                                   \
 325                         if (is_unusable_idx_u32(p, idx))                   \
 326                                 (p)->u.chain32.idx += (p)->elem_unusable;  \
 327                 }                                       \
 328         } while (0)
 329
 330 /**
 331  * @brief qed_chain_return_produced -
 332  *
 333  * A chain in which the driver "Produces" elements should use this API
 334  * to indicate previous produced elements are now consumed.
 335  *
 336  * @param p_chain
 337  */
 338 static inline void qed_chain_return_produced(struct qed_chain *p_chain)
 339 {
 340         if (is_chain_u16(p_chain))
 341                 p_chain->u.chain16.cons_idx++;
 342         else
 343                 p_chain->u.chain32.cons_idx++;
 344         test_and_skip(p_chain, cons_idx);
 345 }
 346
 347 /**
 348  * @brief qed_chain_produce -
 349  *
 350  * A chain in which the driver "Produces" elements should use this to get
 351  * a pointer to the next element which can be "Produced". It's driver
 352  * responsibility to validate that the chain has room for new element.
 353  *
 354  * @param p_chain
 355  *
 356  * @return void*, a pointer to next element
 357  */
 358 static inline void *qed_chain_produce(struct qed_chain *p_chain)
 359 {
 360         void *p_ret = NULL, *p_prod_idx, *p_prod_page_idx;
 361
 362         if (is_chain_u16(p_chain)) {
 363                 if ((p_chain->u.chain16.prod_idx &
 364                      p_chain->elem_per_page_mask) == p_chain->next_page_mask) {
 365                         p_prod_idx = &p_chain->u.chain16.prod_idx;
 366                         p_prod_page_idx = &p_chain->pbl.c.u16.prod_page_idx;
 367                         qed_chain_advance_page(p_chain, &p_chain->p_prod_elem,
 368                                                p_prod_idx, p_prod_page_idx);
 369                 }
 370                 p_chain->u.chain16.prod_idx++;
 371         } else {
 372                 if ((p_chain->u.chain32.prod_idx &
 373                      p_chain->elem_per_page_mask) == p_chain->next_page_mask) {
 374                         p_prod_idx = &p_chain->u.chain32.prod_idx;
 375                         p_prod_page_idx = &p_chain->pbl.c.u32.prod_page_idx;
 376                         qed_chain_advance_page(p_chain, &p_chain->p_prod_elem,
 377                                                p_prod_idx, p_prod_page_idx);
 378                 }
 379                 p_chain->u.chain32.prod_idx++;
 380         }
 381
 382         p_ret = p_chain->p_prod_elem;
 383         p_chain->p_prod_elem = (void *)(((u8 *)p_chain->p_prod_elem) +
 384                                         p_chain->elem_size);
 385
 386         return p_ret;
 387 }
 388
 389 /**
 390  * @brief qed_chain_get_capacity -
 391  *
 392  * Get the maximum number of BDs in chain
 393  *
 394  * @param p_chain
 395  * @param num
 396  *
 397  * @return number of unusable BDs
 398  */
 399 static inline u32 qed_chain_get_capacity(struct qed_chain *p_chain)
 400 {
 401         return p_chain->capacity;
 402 }
 403
 404 /**
 405  * @brief qed_chain_recycle_consumed -
 406  *
 407  * Returns an element which was previously consumed;
 408  * Increments producers so they could be written to FW.
 409  *
 410  * @param p_chain
 411  */
 412 static inline void qed_chain_recycle_consumed(struct qed_chain *p_chain)
 413 {
 414         test_and_skip(p_chain, prod_idx);
 415         if (is_chain_u16(p_chain))
 416                 p_chain->u.chain16.prod_idx++;
 417         else
 418                 p_chain->u.chain32.prod_idx++;
 419 }
 420
 421 /**
 422  * @brief qed_chain_consume -
 423  *
 424  * A Chain in which the driver utilizes data written by a different source
 425  * (i.e., FW) should use this to access passed buffers.
 426  *
 427  * @param p_chain
 428  *
 429  * @return void*, a pointer to the next buffer written
 430  */
 431 static inline void *qed_chain_consume(struct qed_chain *p_chain)
 432 {
 433         void *p_ret = NULL, *p_cons_idx, *p_cons_page_idx;
 434
 435         if (is_chain_u16(p_chain)) {
 436                 if ((p_chain->u.chain16.cons_idx &
 437                      p_chain->elem_per_page_mask) == p_chain->next_page_mask) {
 438                         p_cons_idx = &p_chain->u.chain16.cons_idx;
 439                         p_cons_page_idx = &p_chain->pbl.c.u16.cons_page_idx;
 440                         qed_chain_advance_page(p_chain, &p_chain->p_cons_elem,
 441                                                p_cons_idx, p_cons_page_idx);
 442                 }
 443                 p_chain->u.chain16.cons_idx++;
 444         } else {
 445                 if ((p_chain->u.chain32.cons_idx &
 446                      p_chain->elem_per_page_mask) == p_chain->next_page_mask) {
 447                         p_cons_idx = &p_chain->u.chain32.cons_idx;
 448                         p_cons_page_idx = &p_chain->pbl.c.u32.cons_page_idx;
 449                         qed_chain_advance_page(p_chain, &p_chain->p_cons_elem,
 450                                                p_cons_idx, p_cons_page_idx);
 451                 }
 452                 p_chain->u.chain32.cons_idx++;
 453         }
 454
 455         p_ret = p_chain->p_cons_elem;
 456         p_chain->p_cons_elem = (void *)(((u8 *)p_chain->p_cons_elem) +
 457                                         p_chain->elem_size);
 458
 459         return p_ret;
 460 }
 461
 462 /**
 463  * @brief qed_chain_reset - Resets the chain to its start state
 464  *
 465  * @param p_chain pointer to a previously allocted chain
 466  */
 467 static inline void qed_chain_reset(struct qed_chain *p_chain)
 468 {
 469         u32 i;
 470
 471         if (is_chain_u16(p_chain)) {
 472                 p_chain->u.chain16.prod_idx = 0;
 473                 p_chain->u.chain16.cons_idx = 0;
 474         } else {
 475                 p_chain->u.chain32.prod_idx = 0;
 476                 p_chain->u.chain32.cons_idx = 0;
 477         }
 478         p_chain->p_cons_elem = p_chain->p_virt_addr;
 479         p_chain->p_prod_elem = p_chain->p_virt_addr;
 480
 481         if (p_chain->mode == QED_CHAIN_MODE_PBL) {
 482                 /* Use (page_cnt - 1) as a reset value for the prod/cons page's
 483                  * indices, to avoid unnecessary page advancing on the first
 484                  * call to qed_chain_produce/consume. Instead, the indices
 485                  * will be advanced to page_cnt and then will be wrapped to 0.
 486                  */
 487                 u32 reset_val = p_chain->page_cnt - 1;
 488
 489                 if (is_chain_u16(p_chain)) {
 490                         p_chain->pbl.c.u16.prod_page_idx = (u16)reset_val;
 491                         p_chain->pbl.c.u16.cons_page_idx = (u16)reset_val;
 492                 } else {
 493                         p_chain->pbl.c.u32.prod_page_idx = reset_val;
 494                         p_chain->pbl.c.u32.cons_page_idx = reset_val;
 495                 }
 496         }
 497
 498         switch (p_chain->intended_use) {
 499         case QED_CHAIN_USE_TO_CONSUME:
 500                 /* produce empty elements */
 501                 for (i = 0; i < p_chain->capacity; i++)
 502                         qed_chain_recycle_consumed(p_chain);
 503                 break;
 504
 505         case QED_CHAIN_USE_TO_CONSUME_PRODUCE:
 506         case QED_CHAIN_USE_TO_PRODUCE:
 507         default:
 508                 /* Do nothing */
 509                 break;
 510         }
 511 }
 512
 513 /**
 514  * @brief qed_chain_init - Initalizes a basic chain struct
 515  *
 516  * @param p_chain
 517  * @param p_virt_addr
 518  * @param p_phys_addr   physical address of allocated buffer's beginning
 519  * @param page_cnt      number of pages in the allocated buffer
 520  * @param elem_size     size of each element in the chain
 521  * @param intended_use
 522  * @param mode
 523  */
 524 static inline void qed_chain_init_params(struct qed_chain *p_chain,
 525                                          u32 page_cnt,
 526                                          u8 elem_size,
 527                                          enum qed_chain_use_mode intended_use,
 528                                          enum qed_chain_mode mode,
 529                                          enum qed_chain_cnt_type cnt_type)
 530 {
 531         /* chain fixed parameters */
 532         p_chain->p_virt_addr = NULL;
 533         p_chain->p_phys_addr = 0;
 534         p_chain->elem_size      = elem_size;
 535         p_chain->intended_use = (u8)intended_use;
 536         p_chain->mode           = mode;
 537         p_chain->cnt_type = (u8)cnt_type;
 538
 539         p_chain->elem_per_page = ELEMS_PER_PAGE(elem_size);
 540         p_chain->usable_per_page = USABLE_ELEMS_PER_PAGE(elem_size, mode);
 541         p_chain->elem_per_page_mask = p_chain->elem_per_page - 1;
 542         p_chain->elem_unusable = UNUSABLE_ELEMS_PER_PAGE(elem_size, mode);
 543         p_chain->next_page_mask = (p_chain->usable_per_page &
 544                                    p_chain->elem_per_page_mask);
 545
 546         p_chain->page_cnt = page_cnt;
 547         p_chain->capacity = p_chain->usable_per_page * page_cnt;
 548         p_chain->size = p_chain->elem_per_page * page_cnt;
 549
 550         p_chain->pbl_sp.p_phys_table = 0;
 551         p_chain->pbl_sp.p_virt_table = NULL;
 552         p_chain->pbl.pp_addr_tbl = NULL;
 553 }
 554
 555 /**
 556  * @brief qed_chain_init_mem -
 557  *
 558  * Initalizes a basic chain struct with its chain buffers
 559  *
 560  * @param p_chain
 561  * @param p_virt_addr   virtual address of allocated buffer's beginning
 562  * @param p_phys_addr   physical address of allocated buffer's beginning
 563  *
 564  */
 565 static inline void qed_chain_init_mem(struct qed_chain *p_chain,
 566                                       void *p_virt_addr, dma_addr_t p_phys_addr)
 567 {
 568         p_chain->p_virt_addr = p_virt_addr;
 569         p_chain->p_phys_addr = p_phys_addr;
 570 }
 571
 572 /**
 573  * @brief qed_chain_init_pbl_mem -
 574  *
 575  * Initalizes a basic chain struct with its pbl buffers
 576  *
 577  * @param p_chain
 578  * @param p_virt_pbl    pointer to a pre allocated side table which will hold
 579  *                      virtual page addresses.
 580  * @param p_phys_pbl    pointer to a pre-allocated side table which will hold
 581  *                      physical page addresses.
 582  * @param pp_virt_addr_tbl
 583  *                      pointer to a pre-allocated side table which will hold
 584  *                      the virtual addresses of the chain pages.
 585  *
 586  */
 587 static inline void qed_chain_init_pbl_mem(struct qed_chain *p_chain,
 588                                           void *p_virt_pbl,
 589                                           dma_addr_t p_phys_pbl,
 590                                           struct addr_tbl_entry *pp_addr_tbl)
 591 {
 592         p_chain->pbl_sp.p_phys_table = p_phys_pbl;
 593         p_chain->pbl_sp.p_virt_table = p_virt_pbl;
 594         p_chain->pbl.pp_addr_tbl = pp_addr_tbl;
 595 }
 596
 597 /**
 598  * @brief qed_chain_init_next_ptr_elem -
 599  *
 600  * Initalizes a next pointer element
 601  *
 602  * @param p_chain
 603  * @param p_virt_curr   virtual address of a chain page of which the next
 604  *                      pointer element is initialized
 605  * @param p_virt_next   virtual address of the next chain page
 606  * @param p_phys_next   physical address of the next chain page
 607  *
 608  */
 609 static inline void
 610 qed_chain_init_next_ptr_elem(struct qed_chain *p_chain,
 611                              void *p_virt_curr,
 612                              void *p_virt_next, dma_addr_t p_phys_next)
 613 {
 614         struct qed_chain_next *p_next;
 615         u32 size;
 616
 617         size = p_chain->elem_size * p_chain->usable_per_page;
 618         p_next = (struct qed_chain_next *)((u8 *)p_virt_curr + size);
 619
 620         DMA_REGPAIR_LE(p_next->next_phys, p_phys_next);
 621
 622         p_next->next_virt = p_virt_next;
 623 }
 624
 625 /**
 626  * @brief qed_chain_get_last_elem -
 627  *
 628  * Returns a pointer to the last element of the chain
 629  *
 630  * @param p_chain
 631  *
 632  * @return void*
 633  */
 634 static inline void *qed_chain_get_last_elem(struct qed_chain *p_chain)
 635 {
 636         struct qed_chain_next *p_next = NULL;
 637         void *p_virt_addr = NULL;
 638         u32 size, last_page_idx;
 639
 640         if (!p_chain->p_virt_addr)
 641                 goto out;
 642
 643         switch (p_chain->mode) {
 644         case QED_CHAIN_MODE_NEXT_PTR:
 645                 size = p_chain->elem_size * p_chain->usable_per_page;
 646                 p_virt_addr = p_chain->p_virt_addr;
 647                 p_next = (struct qed_chain_next *)((u8 *)p_virt_addr + size);
 648                 while (p_next->next_virt != p_chain->p_virt_addr) {
 649                         p_virt_addr = p_next->next_virt;
 650                         p_next = (struct qed_chain_next *)((u8 *)p_virt_addr +
 651                                                            size);
 652                 }
 653                 break;
 654         case QED_CHAIN_MODE_SINGLE:
 655                 p_virt_addr = p_chain->p_virt_addr;
 656                 break;
 657         case QED_CHAIN_MODE_PBL:
 658                 last_page_idx = p_chain->page_cnt - 1;
 659                 p_virt_addr = p_chain->pbl.pp_addr_tbl[last_page_idx].virt_addr;
 660                 break;
 661         }
 662         /* p_virt_addr points at this stage to the last page of the chain */
 663         size = p_chain->elem_size * (p_chain->usable_per_page - 1);
 664         p_virt_addr = (u8 *)p_virt_addr + size;
 665 out:
 666         return p_virt_addr;
 667 }
 668
 669 /**
 670  * @brief qed_chain_set_prod - sets the prod to the given value
 671  *
 672  * @param prod_idx
 673  * @param p_prod_elem
 674  */
 675 static inline void qed_chain_set_prod(struct qed_chain *p_chain,
 676                                       u32 prod_idx, void *p_prod_elem)
 677 {
 678         if (p_chain->mode == QED_CHAIN_MODE_PBL) {
 679                 u32 cur_prod, page_mask, page_cnt, page_diff;
 680
 681                 cur_prod = is_chain_u16(p_chain) ? p_chain->u.chain16.prod_idx :
 682                            p_chain->u.chain32.prod_idx;
 683
 684                 /* Assume that number of elements in a page is power of 2 */
 685                 page_mask = ~p_chain->elem_per_page_mask;
 686
 687                 /* Use "cur_prod - 1" and "prod_idx - 1" since producer index
 688                  * reaches the first element of next page before the page index
 689                  * is incremented. See qed_chain_produce().
 690                  * Index wrap around is not a problem because the difference
 691                  * between current and given producer indices is always
 692                  * positive and lower than the chain's capacity.
 693                  */
 694                 page_diff = (((cur_prod - 1) & page_mask) -
 695                              ((prod_idx - 1) & page_mask)) /
 696                             p_chain->elem_per_page;
 697
 698                 page_cnt = qed_chain_get_page_cnt(p_chain);
 699                 if (is_chain_u16(p_chain))
 700                         p_chain->pbl.c.u16.prod_page_idx =
 701                                 (p_chain->pbl.c.u16.prod_page_idx -
 702                                  page_diff + page_cnt) % page_cnt;
 703                 else
 704                         p_chain->pbl.c.u32.prod_page_idx =
 705                                 (p_chain->pbl.c.u32.prod_page_idx -
 706                                  page_diff + page_cnt) % page_cnt;
 707         }
 708
 709         if (is_chain_u16(p_chain))
 710                 p_chain->u.chain16.prod_idx = (u16) prod_idx;
 711         else
 712                 p_chain->u.chain32.prod_idx = prod_idx;
 713         p_chain->p_prod_elem = p_prod_elem;
 714 }
 715
 716 /**
 717  * @brief qed_chain_pbl_zero_mem - set chain memory to 0
 718  *
 719  * @param p_chain
 720  */
 721 static inline void qed_chain_pbl_zero_mem(struct qed_chain *p_chain)
 722 {
 723         u32 i, page_cnt;
 724
 725         if (p_chain->mode != QED_CHAIN_MODE_PBL)
 726                 return;
 727
 728         page_cnt = qed_chain_get_page_cnt(p_chain);
 729
 730         for (i = 0; i < page_cnt; i++)
 731                 memset(p_chain->pbl.pp_addr_tbl[i].virt_addr, 0,
 732                        QED_CHAIN_PAGE_SIZE);
 733 }
 734
 735 #endif