1 // SPDX-License-Identifier: GPL-2.0 2 3 /* Copyright (c) 2012-2018, The Linux Foundation. All rights reserved. 4 * Copyright (C) 2018-2022 Linaro Ltd. 5 */ 6 7 #include <linux/types.h> 8 #include <linux/kernel.h> 9 #include <linux/bits.h> 10 #include <linux/bitops.h> 11 #include <linux/bitfield.h> 12 #include <linux/io.h> 13 #include <linux/build_bug.h> 14 #include <linux/device.h> 15 #include <linux/dma-mapping.h> 16 17 #include "ipa.h" 18 #include "ipa_version.h" 19 #include "ipa_endpoint.h" 20 #include "ipa_table.h" 21 #include "ipa_reg.h" 22 #include "ipa_mem.h" 23 #include "ipa_cmd.h" 24 #include "gsi.h" 25 #include "gsi_trans.h" 26 27 /** 28 * DOC: IPA Filter and Route Tables 29 * 30 * The IPA has tables defined in its local (IPA-resident) memory that define 31 * filter and routing rules. An entry in either of these tables is a little 32 * endian 64-bit "slot" that holds the address of a rule definition. (The 33 * size of these slots is 64 bits regardless of the host DMA address size.) 34 * 35 * Separate tables (both filter and route) are used for IPv4 and IPv6. There 36 * is normally another set of "hashed" filter and route tables, which are 37 * used with a hash of message metadata. Hashed operation is not supported 38 * by all IPA hardware (IPA v4.2 doesn't support hashed tables). 39 * 40 * Rules can be in local memory or in DRAM (system memory). The offset of 41 * an object (such as a route or filter table) in IPA-resident memory must 42 * 128-byte aligned. An object in system memory (such as a route or filter 43 * rule) must be at an 8-byte aligned address. We currently only place 44 * route or filter rules in system memory. 45 * 46 * A rule consists of a contiguous block of 32-bit values terminated with 47 * 32 zero bits. A special "zero entry" rule consisting of 64 zero bits 48 * represents "no filtering" or "no routing," and is the reset value for 49 * filter or route table rules. 50 * 51 * Each filter rule is associated with an AP or modem TX endpoint, though 52 * not all TX endpoints support filtering. The first 64-bit slot in a 53 * filter table is a bitmap indicating which endpoints have entries in 54 * the table. Each set bit in this bitmap indicates the presence of the 55 * address of a filter rule in the memory following the bitmap. Until IPA 56 * v5.0, the low-order bit (bit 0) in this bitmap represents a special 57 * global filter, which applies to all traffic. Otherwise the position of 58 * each set bit represents an endpoint for which a filter rule is defined. 59 * 60 * The global rule is not used in current code, and support for it is 61 * removed starting at IPA v5.0. For IPA v5.0+, the endpoint bitmap 62 * position defines the endpoint ID--i.e. if bit 1 is set in the endpoint 63 * bitmap, endpoint 1 has a filter rule. Older versions of IPA represent 64 * the presence of a filter rule for endpoint X by bit (X + 1) being set. 65 * I.e., bit 1 set indicates the presence of a filter rule for endpoint 0, 66 * and bit 3 set means there is a filter rule present for endpoint 2. 67 * 68 * Each filter table entry has the address of a set of equations that 69 * implement a filter rule. So following the endpoint bitmap there 70 * will be such an address/entry for each endpoint with a set bit in 71 * the bitmap. 72 * 73 * The AP initializes all entries in a filter table to refer to a "zero" 74 * rule. Once initialized, the modem and AP update the entries for 75 * endpoints they "own" directly. Currently the AP does not use the IPA 76 * filtering functionality. 77 * 78 * This diagram shows an example of a filter table with an endpoint 79 * bitmap as defined prior to IPA v5.0. 80 * 81 * IPA Filter Table 82 * ---------------------- 83 * endpoint bitmap | 0x0000000000000048 | Bits 3 and 6 set (endpoints 2 and 5) 84 * |--------------------| 85 * 1st endpoint | 0x000123456789abc0 | DMA address for modem endpoint 2 rule 86 * |--------------------| 87 * 2nd endpoint | 0x000123456789abf0 | DMA address for AP endpoint 5 rule 88 * |--------------------| 89 * (unused) | | (Unused space in filter table) 90 * |--------------------| 91 * . . . 92 * |--------------------| 93 * (unused) | | (Unused space in filter table) 94 * ---------------------- 95 * 96 * The set of available route rules is divided about equally between the AP 97 * and modem. The AP initializes all entries in a route table to refer to 98 * a "zero entry". Once initialized, the modem and AP are responsible for 99 * updating their own entries. All entries in a route table are usable, 100 * though the AP currently does not use the IPA routing functionality. 101 * 102 * IPA Route Table 103 * ---------------------- 104 * 1st modem route | 0x0001234500001100 | DMA address for first route rule 105 * |--------------------| 106 * 2nd modem route | 0x0001234500001140 | DMA address for second route rule 107 * |--------------------| 108 * . . . 109 * |--------------------| 110 * Last modem route| 0x0001234500002280 | DMA address for Nth route rule 111 * |--------------------| 112 * 1st AP route | 0x0001234500001100 | DMA address for route rule (N+1) 113 * |--------------------| 114 * 2nd AP route | 0x0001234500001140 | DMA address for next route rule 115 * |--------------------| 116 * . . . 117 * |--------------------| 118 * Last AP route | 0x0001234500002280 | DMA address for last route rule 119 * ---------------------- 120 */ 121 122 /* Filter or route rules consist of a set of 32-bit values followed by a 123 * 32-bit all-zero rule list terminator. The "zero rule" is simply an 124 * all-zero rule followed by the list terminator. 125 */ 126 #define IPA_ZERO_RULE_SIZE (2 * sizeof(__le32)) 127 128 /* Check things that can be validated at build time. */ 129 static void ipa_table_validate_build(void) 130 { 131 /* Filter and route tables contain DMA addresses that refer 132 * to filter or route rules. But the size of a table entry 133 * is 64 bits regardless of what the size of an AP DMA address 134 * is. A fixed constant defines the size of an entry, and 135 * code in ipa_table_init() uses a pointer to __le64 to 136 * initialize tables. 137 */ 138 BUILD_BUG_ON(sizeof(dma_addr_t) > sizeof(__le64)); 139 140 /* A "zero rule" is used to represent no filtering or no routing. 141 * It is a 64-bit block of zeroed memory. Code in ipa_table_init() 142 * assumes that it can be written using a pointer to __le64. 143 */ 144 BUILD_BUG_ON(IPA_ZERO_RULE_SIZE != sizeof(__le64)); 145 } 146 147 static const struct ipa_mem * 148 ipa_table_mem(struct ipa *ipa, bool filter, bool hashed, bool ipv6) 149 { 150 enum ipa_mem_id mem_id; 151 152 mem_id = filter ? hashed ? ipv6 ? IPA_MEM_V6_FILTER_HASHED 153 : IPA_MEM_V4_FILTER_HASHED 154 : ipv6 ? IPA_MEM_V6_FILTER 155 : IPA_MEM_V4_FILTER 156 : hashed ? ipv6 ? IPA_MEM_V6_ROUTE_HASHED 157 : IPA_MEM_V4_ROUTE_HASHED 158 : ipv6 ? IPA_MEM_V6_ROUTE 159 : IPA_MEM_V4_ROUTE; 160 161 return ipa_mem_find(ipa, mem_id); 162 } 163 164 bool ipa_filtered_valid(struct ipa *ipa, u64 filtered) 165 { 166 struct device *dev = &ipa->pdev->dev; 167 u32 count; 168 169 if (!filtered) { 170 dev_err(dev, "at least one filtering endpoint is required\n"); 171 172 return false; 173 } 174 175 count = hweight64(filtered); 176 if (count > ipa->filter_count) { 177 dev_err(dev, "too many filtering endpoints (%u > %u)\n", 178 count, ipa->filter_count); 179 180 return false; 181 } 182 183 return true; 184 } 185 186 /* Zero entry count means no table, so just return a 0 address */ 187 static dma_addr_t ipa_table_addr(struct ipa *ipa, bool filter_mask, u16 count) 188 { 189 u32 skip; 190 191 if (!count) 192 return 0; 193 194 WARN_ON(count > max_t(u32, ipa->filter_count, ipa->route_count)); 195 196 /* Skip over the zero rule and possibly the filter mask */ 197 skip = filter_mask ? 1 : 2; 198 199 return ipa->table_addr + skip * sizeof(*ipa->table_virt); 200 } 201 202 static void ipa_table_reset_add(struct gsi_trans *trans, bool filter, 203 bool hashed, bool ipv6, u16 first, u16 count) 204 { 205 struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi); 206 const struct ipa_mem *mem; 207 dma_addr_t addr; 208 u32 offset; 209 u16 size; 210 211 /* Nothing to do if the memory region is doesn't exist or is empty */ 212 mem = ipa_table_mem(ipa, filter, hashed, ipv6); 213 if (!mem || !mem->size) 214 return; 215 216 if (filter) 217 first++; /* skip over bitmap */ 218 219 offset = mem->offset + first * sizeof(__le64); 220 size = count * sizeof(__le64); 221 addr = ipa_table_addr(ipa, false, count); 222 223 ipa_cmd_dma_shared_mem_add(trans, offset, size, addr, true); 224 } 225 226 /* Reset entries in a single filter table belonging to either the AP or 227 * modem to refer to the zero entry. The memory region supplied will be 228 * for the IPv4 and IPv6 non-hashed and hashed filter tables. 229 */ 230 static int 231 ipa_filter_reset_table(struct ipa *ipa, bool hashed, bool ipv6, bool modem) 232 { 233 u64 ep_mask = ipa->filtered; 234 struct gsi_trans *trans; 235 enum gsi_ee_id ee_id; 236 237 trans = ipa_cmd_trans_alloc(ipa, hweight64(ep_mask)); 238 if (!trans) { 239 dev_err(&ipa->pdev->dev, 240 "no transaction for %s filter reset\n", 241 modem ? "modem" : "AP"); 242 return -EBUSY; 243 } 244 245 ee_id = modem ? GSI_EE_MODEM : GSI_EE_AP; 246 while (ep_mask) { 247 u32 endpoint_id = __ffs(ep_mask); 248 struct ipa_endpoint *endpoint; 249 250 ep_mask ^= BIT(endpoint_id); 251 252 endpoint = &ipa->endpoint[endpoint_id]; 253 if (endpoint->ee_id != ee_id) 254 continue; 255 256 ipa_table_reset_add(trans, true, hashed, ipv6, endpoint_id, 1); 257 } 258 259 gsi_trans_commit_wait(trans); 260 261 return 0; 262 } 263 264 /* Theoretically, each filter table could have more filter slots to 265 * update than the maximum number of commands in a transaction. So 266 * we do each table separately. 267 */ 268 static int ipa_filter_reset(struct ipa *ipa, bool modem) 269 { 270 int ret; 271 272 ret = ipa_filter_reset_table(ipa, false, false, modem); 273 if (ret) 274 return ret; 275 276 ret = ipa_filter_reset_table(ipa, true, false, modem); 277 if (ret) 278 return ret; 279 280 ret = ipa_filter_reset_table(ipa, false, true, modem); 281 if (ret) 282 return ret; 283 ret = ipa_filter_reset_table(ipa, true, true, modem); 284 285 return ret; 286 } 287 288 /* The AP routes and modem routes are each contiguous within the 289 * table. We can update each table with a single command, and we 290 * won't exceed the per-transaction command limit. 291 * */ 292 static int ipa_route_reset(struct ipa *ipa, bool modem) 293 { 294 u32 modem_route_count = ipa->modem_route_count; 295 struct gsi_trans *trans; 296 u16 first; 297 u16 count; 298 299 trans = ipa_cmd_trans_alloc(ipa, 4); 300 if (!trans) { 301 dev_err(&ipa->pdev->dev, 302 "no transaction for %s route reset\n", 303 modem ? "modem" : "AP"); 304 return -EBUSY; 305 } 306 307 if (modem) { 308 first = 0; 309 count = modem_route_count; 310 } else { 311 first = modem_route_count; 312 count = ipa->route_count - modem_route_count; 313 } 314 315 ipa_table_reset_add(trans, false, false, false, first, count); 316 ipa_table_reset_add(trans, false, true, false, first, count); 317 318 ipa_table_reset_add(trans, false, false, true, first, count); 319 ipa_table_reset_add(trans, false, true, true, first, count); 320 321 gsi_trans_commit_wait(trans); 322 323 return 0; 324 } 325 326 void ipa_table_reset(struct ipa *ipa, bool modem) 327 { 328 struct device *dev = &ipa->pdev->dev; 329 const char *ee_name; 330 int ret; 331 332 ee_name = modem ? "modem" : "AP"; 333 334 /* Report errors, but reset filter and route tables */ 335 ret = ipa_filter_reset(ipa, modem); 336 if (ret) 337 dev_err(dev, "error %d resetting filter table for %s\n", 338 ret, ee_name); 339 340 ret = ipa_route_reset(ipa, modem); 341 if (ret) 342 dev_err(dev, "error %d resetting route table for %s\n", 343 ret, ee_name); 344 } 345 346 int ipa_table_hash_flush(struct ipa *ipa) 347 { 348 const struct ipa_reg *reg; 349 struct gsi_trans *trans; 350 u32 offset; 351 u32 val; 352 353 if (!ipa_table_hash_support(ipa)) 354 return 0; 355 356 trans = ipa_cmd_trans_alloc(ipa, 1); 357 if (!trans) { 358 dev_err(&ipa->pdev->dev, "no transaction for hash flush\n"); 359 return -EBUSY; 360 } 361 362 reg = ipa_reg(ipa, FILT_ROUT_HASH_FLUSH); 363 offset = ipa_reg_offset(reg); 364 365 val = ipa_reg_bit(reg, IPV6_ROUTER_HASH); 366 val |= ipa_reg_bit(reg, IPV6_FILTER_HASH); 367 val |= ipa_reg_bit(reg, IPV4_ROUTER_HASH); 368 val |= ipa_reg_bit(reg, IPV4_FILTER_HASH); 369 370 ipa_cmd_register_write_add(trans, offset, val, val, false); 371 372 gsi_trans_commit_wait(trans); 373 374 return 0; 375 } 376 377 static void ipa_table_init_add(struct gsi_trans *trans, bool filter, bool ipv6) 378 { 379 struct ipa *ipa = container_of(trans->gsi, struct ipa, gsi); 380 const struct ipa_mem *hash_mem; 381 enum ipa_cmd_opcode opcode; 382 const struct ipa_mem *mem; 383 dma_addr_t hash_addr; 384 dma_addr_t addr; 385 u32 hash_offset; 386 u32 zero_offset; 387 u16 hash_count; 388 u32 zero_size; 389 u16 hash_size; 390 u16 count; 391 u16 size; 392 393 opcode = filter ? ipv6 ? IPA_CMD_IP_V6_FILTER_INIT 394 : IPA_CMD_IP_V4_FILTER_INIT 395 : ipv6 ? IPA_CMD_IP_V6_ROUTING_INIT 396 : IPA_CMD_IP_V4_ROUTING_INIT; 397 398 /* The non-hashed region will exist (see ipa_table_mem_valid()) */ 399 mem = ipa_table_mem(ipa, filter, false, ipv6); 400 hash_mem = ipa_table_mem(ipa, filter, true, ipv6); 401 hash_offset = hash_mem ? hash_mem->offset : 0; 402 403 /* Compute the number of table entries to initialize */ 404 if (filter) { 405 /* The number of filtering endpoints determines number of 406 * entries in the filter table; we also add one more "slot" 407 * to hold the bitmap itself. The size of the hashed filter 408 * table is either the same as the non-hashed one, or zero. 409 */ 410 count = 1 + hweight64(ipa->filtered); 411 hash_count = hash_mem && hash_mem->size ? count : 0; 412 } else { 413 /* The size of a route table region determines the number 414 * of entries it has. 415 */ 416 count = mem->size / sizeof(__le64); 417 hash_count = hash_mem ? hash_mem->size / sizeof(__le64) : 0; 418 } 419 size = count * sizeof(__le64); 420 hash_size = hash_count * sizeof(__le64); 421 422 addr = ipa_table_addr(ipa, filter, count); 423 hash_addr = ipa_table_addr(ipa, filter, hash_count); 424 425 ipa_cmd_table_init_add(trans, opcode, size, mem->offset, addr, 426 hash_size, hash_offset, hash_addr); 427 if (!filter) 428 return; 429 430 /* Zero the unused space in the filter table */ 431 zero_offset = mem->offset + size; 432 zero_size = mem->size - size; 433 ipa_cmd_dma_shared_mem_add(trans, zero_offset, zero_size, 434 ipa->zero_addr, true); 435 if (!hash_size) 436 return; 437 438 /* Zero the unused space in the hashed filter table */ 439 zero_offset = hash_offset + hash_size; 440 zero_size = hash_mem->size - hash_size; 441 ipa_cmd_dma_shared_mem_add(trans, zero_offset, zero_size, 442 ipa->zero_addr, true); 443 } 444 445 int ipa_table_setup(struct ipa *ipa) 446 { 447 struct gsi_trans *trans; 448 449 /* We will need at most 8 TREs: 450 * - IPv4: 451 * - One for route table initialization (non-hashed and hashed) 452 * - One for filter table initialization (non-hashed and hashed) 453 * - One to zero unused entries in the non-hashed filter table 454 * - One to zero unused entries in the hashed filter table 455 * - IPv6: 456 * - One for route table initialization (non-hashed and hashed) 457 * - One for filter table initialization (non-hashed and hashed) 458 * - One to zero unused entries in the non-hashed filter table 459 * - One to zero unused entries in the hashed filter table 460 * All platforms support at least 8 TREs in a transaction. 461 */ 462 trans = ipa_cmd_trans_alloc(ipa, 8); 463 if (!trans) { 464 dev_err(&ipa->pdev->dev, "no transaction for table setup\n"); 465 return -EBUSY; 466 } 467 468 ipa_table_init_add(trans, false, false); 469 ipa_table_init_add(trans, false, true); 470 ipa_table_init_add(trans, true, false); 471 ipa_table_init_add(trans, true, true); 472 473 gsi_trans_commit_wait(trans); 474 475 return 0; 476 } 477 478 /** 479 * ipa_filter_tuple_zero() - Zero an endpoint's hashed filter tuple 480 * @endpoint: Endpoint whose filter hash tuple should be zeroed 481 * 482 * Endpoint must be for the AP (not modem) and support filtering. Updates 483 * the filter hash values without changing route ones. 484 */ 485 static void ipa_filter_tuple_zero(struct ipa_endpoint *endpoint) 486 { 487 u32 endpoint_id = endpoint->endpoint_id; 488 struct ipa *ipa = endpoint->ipa; 489 const struct ipa_reg *reg; 490 u32 offset; 491 u32 val; 492 493 reg = ipa_reg(ipa, ENDP_FILTER_ROUTER_HSH_CFG); 494 495 offset = ipa_reg_n_offset(reg, endpoint_id); 496 val = ioread32(endpoint->ipa->reg_virt + offset); 497 498 /* Zero all filter-related fields, preserving the rest */ 499 val &= ~ipa_reg_fmask(reg, FILTER_HASH_MSK_ALL); 500 501 iowrite32(val, endpoint->ipa->reg_virt + offset); 502 } 503 504 /* Configure a hashed filter table; there is no ipa_filter_deconfig() */ 505 static void ipa_filter_config(struct ipa *ipa, bool modem) 506 { 507 enum gsi_ee_id ee_id = modem ? GSI_EE_MODEM : GSI_EE_AP; 508 u64 ep_mask = ipa->filtered; 509 510 if (!ipa_table_hash_support(ipa)) 511 return; 512 513 while (ep_mask) { 514 u32 endpoint_id = __ffs(ep_mask); 515 struct ipa_endpoint *endpoint; 516 517 ep_mask ^= BIT(endpoint_id); 518 519 endpoint = &ipa->endpoint[endpoint_id]; 520 if (endpoint->ee_id == ee_id) 521 ipa_filter_tuple_zero(endpoint); 522 } 523 } 524 525 static bool ipa_route_id_modem(struct ipa *ipa, u32 route_id) 526 { 527 return route_id < ipa->modem_route_count; 528 } 529 530 /** 531 * ipa_route_tuple_zero() - Zero a hashed route table entry tuple 532 * @ipa: IPA pointer 533 * @route_id: Route table entry whose hash tuple should be zeroed 534 * 535 * Updates the route hash values without changing filter ones. 536 */ 537 static void ipa_route_tuple_zero(struct ipa *ipa, u32 route_id) 538 { 539 const struct ipa_reg *reg; 540 u32 offset; 541 u32 val; 542 543 reg = ipa_reg(ipa, ENDP_FILTER_ROUTER_HSH_CFG); 544 offset = ipa_reg_n_offset(reg, route_id); 545 546 val = ioread32(ipa->reg_virt + offset); 547 548 /* Zero all route-related fields, preserving the rest */ 549 val &= ~ipa_reg_fmask(reg, ROUTER_HASH_MSK_ALL); 550 551 iowrite32(val, ipa->reg_virt + offset); 552 } 553 554 /* Configure a hashed route table; there is no ipa_route_deconfig() */ 555 static void ipa_route_config(struct ipa *ipa, bool modem) 556 { 557 u32 route_id; 558 559 if (!ipa_table_hash_support(ipa)) 560 return; 561 562 for (route_id = 0; route_id < ipa->route_count; route_id++) 563 if (ipa_route_id_modem(ipa, route_id) == modem) 564 ipa_route_tuple_zero(ipa, route_id); 565 } 566 567 /* Configure a filter and route tables; there is no ipa_table_deconfig() */ 568 void ipa_table_config(struct ipa *ipa) 569 { 570 ipa_filter_config(ipa, false); 571 ipa_filter_config(ipa, true); 572 ipa_route_config(ipa, false); 573 ipa_route_config(ipa, true); 574 } 575 576 /* Verify the sizes of all IPA table filter or routing table memory regions 577 * are valid. If valid, this records the size of the routing table. 578 */ 579 bool ipa_table_mem_valid(struct ipa *ipa, bool filter) 580 { 581 bool hash_support = ipa_table_hash_support(ipa); 582 const struct ipa_mem *mem_hashed; 583 const struct ipa_mem *mem_ipv4; 584 const struct ipa_mem *mem_ipv6; 585 u32 count; 586 587 /* IPv4 and IPv6 non-hashed tables are expected to be defined and 588 * have the same size. Both must have at least two entries (and 589 * would normally have more than that). 590 */ 591 mem_ipv4 = ipa_table_mem(ipa, filter, false, false); 592 if (!mem_ipv4) 593 return false; 594 595 mem_ipv6 = ipa_table_mem(ipa, filter, false, true); 596 if (!mem_ipv6) 597 return false; 598 599 if (mem_ipv4->size != mem_ipv6->size) 600 return false; 601 602 /* Compute and record the number of entries for each table type */ 603 count = mem_ipv4->size / sizeof(__le64); 604 if (count < 2) 605 return false; 606 if (filter) 607 ipa->filter_count = count - 1; /* Filter map in first entry */ 608 else 609 ipa->route_count = count; 610 611 /* Table offset and size must fit in TABLE_INIT command fields */ 612 if (!ipa_cmd_table_init_valid(ipa, mem_ipv4, !filter)) 613 return false; 614 615 /* Make sure the regions are big enough */ 616 if (filter) { 617 /* Filter tables must able to hold the endpoint bitmap plus 618 * an entry for each endpoint that supports filtering 619 */ 620 if (count < 1 + hweight64(ipa->filtered)) 621 return false; 622 } else { 623 /* Routing tables must be able to hold all modem entries, 624 * plus at least one entry for the AP. 625 */ 626 if (count < ipa->modem_route_count + 1) 627 return false; 628 } 629 630 /* If hashing is supported, hashed tables are expected to be defined, 631 * and have the same size as non-hashed tables. If hashing is not 632 * supported, hashed tables are expected to have zero size (or not 633 * be defined). 634 */ 635 mem_hashed = ipa_table_mem(ipa, filter, true, false); 636 if (hash_support) { 637 if (!mem_hashed || mem_hashed->size != mem_ipv4->size) 638 return false; 639 } else { 640 if (mem_hashed && mem_hashed->size) 641 return false; 642 } 643 644 /* Same check for IPv6 tables */ 645 mem_hashed = ipa_table_mem(ipa, filter, true, true); 646 if (hash_support) { 647 if (!mem_hashed || mem_hashed->size != mem_ipv6->size) 648 return false; 649 } else { 650 if (mem_hashed && mem_hashed->size) 651 return false; 652 } 653 654 return true; 655 } 656 657 /* Initialize a coherent DMA allocation containing initialized filter and 658 * route table data. This is used when initializing or resetting the IPA 659 * filter or route table. 660 * 661 * The first entry in a filter table contains a bitmap indicating which 662 * endpoints contain entries in the table. In addition to that first entry, 663 * there is a fixed maximum number of entries that follow. Filter table 664 * entries are 64 bits wide, and (other than the bitmap) contain the DMA 665 * address of a filter rule. A "zero rule" indicates no filtering, and 666 * consists of 64 bits of zeroes. When a filter table is initialized (or 667 * reset) its entries are made to refer to the zero rule. 668 * 669 * Each entry in a route table is the DMA address of a routing rule. For 670 * routing there is also a 64-bit "zero rule" that means no routing, and 671 * when a route table is initialized or reset, its entries are made to refer 672 * to the zero rule. The zero rule is shared for route and filter tables. 673 * 674 * +-------------------+ 675 * --> | zero rule | 676 * / |-------------------| 677 * | | filter mask | 678 * |\ |-------------------| 679 * | ---- zero rule address | \ 680 * |\ |-------------------| | 681 * | ---- zero rule address | | Max IPA filter count 682 * | |-------------------| > or IPA route count, 683 * | ... | whichever is greater 684 * \ |-------------------| | 685 * ---- zero rule address | / 686 * +-------------------+ 687 */ 688 int ipa_table_init(struct ipa *ipa) 689 { 690 struct device *dev = &ipa->pdev->dev; 691 dma_addr_t addr; 692 __le64 le_addr; 693 __le64 *virt; 694 size_t size; 695 u32 count; 696 697 ipa_table_validate_build(); 698 699 count = max_t(u32, ipa->filter_count, ipa->route_count); 700 701 /* The IPA hardware requires route and filter table rules to be 702 * aligned on a 128-byte boundary. We put the "zero rule" at the 703 * base of the table area allocated here. The DMA address returned 704 * by dma_alloc_coherent() is guaranteed to be a power-of-2 number 705 * of pages, which satisfies the rule alignment requirement. 706 */ 707 size = IPA_ZERO_RULE_SIZE + (1 + count) * sizeof(__le64); 708 virt = dma_alloc_coherent(dev, size, &addr, GFP_KERNEL); 709 if (!virt) 710 return -ENOMEM; 711 712 ipa->table_virt = virt; 713 ipa->table_addr = addr; 714 715 /* First slot is the zero rule */ 716 *virt++ = 0; 717 718 /* Next is the filter table bitmap. The "soft" bitmap value might 719 * need to be converted to the hardware representation by shifting 720 * it left one position. Prior to IPA v5.0, bit 0 repesents global 721 * filtering, which is possible but not used. IPA v5.0+ eliminated 722 * that option, so there's no shifting required. 723 */ 724 if (ipa->version < IPA_VERSION_5_0) 725 *virt++ = cpu_to_le64(ipa->filtered << 1); 726 else 727 *virt++ = cpu_to_le64(ipa->filtered); 728 729 /* All the rest contain the DMA address of the zero rule */ 730 le_addr = cpu_to_le64(addr); 731 while (count--) 732 *virt++ = le_addr; 733 734 return 0; 735 } 736 737 void ipa_table_exit(struct ipa *ipa) 738 { 739 u32 count = max_t(u32, 1 + ipa->filter_count, ipa->route_count); 740 struct device *dev = &ipa->pdev->dev; 741 size_t size; 742 743 size = IPA_ZERO_RULE_SIZE + (1 + count) * sizeof(__le64); 744 745 dma_free_coherent(dev, size, ipa->table_virt, ipa->table_addr); 746 ipa->table_addr = 0; 747 ipa->table_virt = NULL; 748 } 749