1 // SPDX-License-Identifier: GPL-2.0-only 2 /* Copyright(c) 2022 Intel Corporation. All rights reserved. */ 3 #include <linux/io-64-nonatomic-hi-lo.h> 4 #include <linux/seq_file.h> 5 #include <linux/device.h> 6 #include <linux/delay.h> 7 8 #include "cxlmem.h" 9 #include "core.h" 10 11 /** 12 * DOC: cxl core hdm 13 * 14 * Compute Express Link Host Managed Device Memory, starting with the 15 * CXL 2.0 specification, is managed by an array of HDM Decoder register 16 * instances per CXL port and per CXL endpoint. Define common helpers 17 * for enumerating these registers and capabilities. 18 */ 19 20 DECLARE_RWSEM(cxl_dpa_rwsem); 21 22 static int add_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld, 23 int *target_map) 24 { 25 int rc; 26 27 rc = cxl_decoder_add_locked(cxld, target_map); 28 if (rc) { 29 put_device(&cxld->dev); 30 dev_err(&port->dev, "Failed to add decoder\n"); 31 return rc; 32 } 33 34 rc = cxl_decoder_autoremove(&port->dev, cxld); 35 if (rc) 36 return rc; 37 38 dev_dbg(&cxld->dev, "Added to port %s\n", dev_name(&port->dev)); 39 40 return 0; 41 } 42 43 /* 44 * Per the CXL specification (8.2.5.12 CXL HDM Decoder Capability Structure) 45 * single ported host-bridges need not publish a decoder capability when a 46 * passthrough decode can be assumed, i.e. all transactions that the uport sees 47 * are claimed and passed to the single dport. Disable the range until the first 48 * CXL region is enumerated / activated. 49 */ 50 int devm_cxl_add_passthrough_decoder(struct cxl_port *port) 51 { 52 struct cxl_switch_decoder *cxlsd; 53 struct cxl_dport *dport = NULL; 54 int single_port_map[1]; 55 unsigned long index; 56 57 cxlsd = cxl_switch_decoder_alloc(port, 1); 58 if (IS_ERR(cxlsd)) 59 return PTR_ERR(cxlsd); 60 61 device_lock_assert(&port->dev); 62 63 xa_for_each(&port->dports, index, dport) 64 break; 65 single_port_map[0] = dport->port_id; 66 67 return add_hdm_decoder(port, &cxlsd->cxld, single_port_map); 68 } 69 EXPORT_SYMBOL_NS_GPL(devm_cxl_add_passthrough_decoder, CXL); 70 71 static void parse_hdm_decoder_caps(struct cxl_hdm *cxlhdm) 72 { 73 u32 hdm_cap; 74 75 hdm_cap = readl(cxlhdm->regs.hdm_decoder + CXL_HDM_DECODER_CAP_OFFSET); 76 cxlhdm->decoder_count = cxl_hdm_decoder_count(hdm_cap); 77 cxlhdm->target_count = 78 FIELD_GET(CXL_HDM_DECODER_TARGET_COUNT_MASK, hdm_cap); 79 if (FIELD_GET(CXL_HDM_DECODER_INTERLEAVE_11_8, hdm_cap)) 80 cxlhdm->interleave_mask |= GENMASK(11, 8); 81 if (FIELD_GET(CXL_HDM_DECODER_INTERLEAVE_14_12, hdm_cap)) 82 cxlhdm->interleave_mask |= GENMASK(14, 12); 83 } 84 85 static int map_hdm_decoder_regs(struct cxl_port *port, void __iomem *crb, 86 struct cxl_component_regs *regs) 87 { 88 struct cxl_register_map map = { 89 .resource = port->component_reg_phys, 90 .base = crb, 91 .max_size = CXL_COMPONENT_REG_BLOCK_SIZE, 92 }; 93 94 cxl_probe_component_regs(&port->dev, crb, &map.component_map); 95 if (!map.component_map.hdm_decoder.valid) { 96 dev_err(&port->dev, "HDM decoder registers invalid\n"); 97 return -ENXIO; 98 } 99 100 return cxl_map_component_regs(&port->dev, regs, &map, 101 BIT(CXL_CM_CAP_CAP_ID_HDM)); 102 } 103 104 /** 105 * devm_cxl_setup_hdm - map HDM decoder component registers 106 * @port: cxl_port to map 107 */ 108 struct cxl_hdm *devm_cxl_setup_hdm(struct cxl_port *port) 109 { 110 struct device *dev = &port->dev; 111 struct cxl_hdm *cxlhdm; 112 void __iomem *crb; 113 int rc; 114 115 cxlhdm = devm_kzalloc(dev, sizeof(*cxlhdm), GFP_KERNEL); 116 if (!cxlhdm) 117 return ERR_PTR(-ENOMEM); 118 119 cxlhdm->port = port; 120 crb = ioremap(port->component_reg_phys, CXL_COMPONENT_REG_BLOCK_SIZE); 121 if (!crb) { 122 dev_err(dev, "No component registers mapped\n"); 123 return ERR_PTR(-ENXIO); 124 } 125 126 rc = map_hdm_decoder_regs(port, crb, &cxlhdm->regs); 127 iounmap(crb); 128 if (rc) 129 return ERR_PTR(rc); 130 131 parse_hdm_decoder_caps(cxlhdm); 132 if (cxlhdm->decoder_count == 0) { 133 dev_err(dev, "Spec violation. Caps invalid\n"); 134 return ERR_PTR(-ENXIO); 135 } 136 137 dev_set_drvdata(dev, cxlhdm); 138 139 return cxlhdm; 140 } 141 EXPORT_SYMBOL_NS_GPL(devm_cxl_setup_hdm, CXL); 142 143 static void __cxl_dpa_debug(struct seq_file *file, struct resource *r, int depth) 144 { 145 unsigned long long start = r->start, end = r->end; 146 147 seq_printf(file, "%*s%08llx-%08llx : %s\n", depth * 2, "", start, end, 148 r->name); 149 } 150 151 void cxl_dpa_debug(struct seq_file *file, struct cxl_dev_state *cxlds) 152 { 153 struct resource *p1, *p2; 154 155 down_read(&cxl_dpa_rwsem); 156 for (p1 = cxlds->dpa_res.child; p1; p1 = p1->sibling) { 157 __cxl_dpa_debug(file, p1, 0); 158 for (p2 = p1->child; p2; p2 = p2->sibling) 159 __cxl_dpa_debug(file, p2, 1); 160 } 161 up_read(&cxl_dpa_rwsem); 162 } 163 EXPORT_SYMBOL_NS_GPL(cxl_dpa_debug, CXL); 164 165 /* 166 * Must be called in a context that synchronizes against this decoder's 167 * port ->remove() callback (like an endpoint decoder sysfs attribute) 168 */ 169 static void __cxl_dpa_release(struct cxl_endpoint_decoder *cxled) 170 { 171 struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); 172 struct cxl_port *port = cxled_to_port(cxled); 173 struct cxl_dev_state *cxlds = cxlmd->cxlds; 174 struct resource *res = cxled->dpa_res; 175 resource_size_t skip_start; 176 177 lockdep_assert_held_write(&cxl_dpa_rwsem); 178 179 /* save @skip_start, before @res is released */ 180 skip_start = res->start - cxled->skip; 181 __release_region(&cxlds->dpa_res, res->start, resource_size(res)); 182 if (cxled->skip) 183 __release_region(&cxlds->dpa_res, skip_start, cxled->skip); 184 cxled->skip = 0; 185 cxled->dpa_res = NULL; 186 put_device(&cxled->cxld.dev); 187 port->hdm_end--; 188 } 189 190 static void cxl_dpa_release(void *cxled) 191 { 192 down_write(&cxl_dpa_rwsem); 193 __cxl_dpa_release(cxled); 194 up_write(&cxl_dpa_rwsem); 195 } 196 197 /* 198 * Must be called from context that will not race port device 199 * unregistration, like decoder sysfs attribute methods 200 */ 201 static void devm_cxl_dpa_release(struct cxl_endpoint_decoder *cxled) 202 { 203 struct cxl_port *port = cxled_to_port(cxled); 204 205 lockdep_assert_held_write(&cxl_dpa_rwsem); 206 devm_remove_action(&port->dev, cxl_dpa_release, cxled); 207 __cxl_dpa_release(cxled); 208 } 209 210 static int __cxl_dpa_reserve(struct cxl_endpoint_decoder *cxled, 211 resource_size_t base, resource_size_t len, 212 resource_size_t skipped) 213 { 214 struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); 215 struct cxl_port *port = cxled_to_port(cxled); 216 struct cxl_dev_state *cxlds = cxlmd->cxlds; 217 struct device *dev = &port->dev; 218 struct resource *res; 219 220 lockdep_assert_held_write(&cxl_dpa_rwsem); 221 222 if (!len) 223 goto success; 224 225 if (cxled->dpa_res) { 226 dev_dbg(dev, "decoder%d.%d: existing allocation %pr assigned\n", 227 port->id, cxled->cxld.id, cxled->dpa_res); 228 return -EBUSY; 229 } 230 231 if (port->hdm_end + 1 != cxled->cxld.id) { 232 /* 233 * Assumes alloc and commit order is always in hardware instance 234 * order per expectations from 8.2.5.12.20 Committing Decoder 235 * Programming that enforce decoder[m] committed before 236 * decoder[m+1] commit start. 237 */ 238 dev_dbg(dev, "decoder%d.%d: expected decoder%d.%d\n", port->id, 239 cxled->cxld.id, port->id, port->hdm_end + 1); 240 return -EBUSY; 241 } 242 243 if (skipped) { 244 res = __request_region(&cxlds->dpa_res, base - skipped, skipped, 245 dev_name(&cxled->cxld.dev), 0); 246 if (!res) { 247 dev_dbg(dev, 248 "decoder%d.%d: failed to reserve skipped space\n", 249 port->id, cxled->cxld.id); 250 return -EBUSY; 251 } 252 } 253 res = __request_region(&cxlds->dpa_res, base, len, 254 dev_name(&cxled->cxld.dev), 0); 255 if (!res) { 256 dev_dbg(dev, "decoder%d.%d: failed to reserve allocation\n", 257 port->id, cxled->cxld.id); 258 if (skipped) 259 __release_region(&cxlds->dpa_res, base - skipped, 260 skipped); 261 return -EBUSY; 262 } 263 cxled->dpa_res = res; 264 cxled->skip = skipped; 265 266 if (resource_contains(&cxlds->pmem_res, res)) 267 cxled->mode = CXL_DECODER_PMEM; 268 else if (resource_contains(&cxlds->ram_res, res)) 269 cxled->mode = CXL_DECODER_RAM; 270 else { 271 dev_dbg(dev, "decoder%d.%d: %pr mixed\n", port->id, 272 cxled->cxld.id, cxled->dpa_res); 273 cxled->mode = CXL_DECODER_MIXED; 274 } 275 276 success: 277 port->hdm_end++; 278 get_device(&cxled->cxld.dev); 279 return 0; 280 } 281 282 static int devm_cxl_dpa_reserve(struct cxl_endpoint_decoder *cxled, 283 resource_size_t base, resource_size_t len, 284 resource_size_t skipped) 285 { 286 struct cxl_port *port = cxled_to_port(cxled); 287 int rc; 288 289 down_write(&cxl_dpa_rwsem); 290 rc = __cxl_dpa_reserve(cxled, base, len, skipped); 291 up_write(&cxl_dpa_rwsem); 292 293 if (rc) 294 return rc; 295 296 return devm_add_action_or_reset(&port->dev, cxl_dpa_release, cxled); 297 } 298 299 resource_size_t cxl_dpa_size(struct cxl_endpoint_decoder *cxled) 300 { 301 resource_size_t size = 0; 302 303 down_read(&cxl_dpa_rwsem); 304 if (cxled->dpa_res) 305 size = resource_size(cxled->dpa_res); 306 up_read(&cxl_dpa_rwsem); 307 308 return size; 309 } 310 311 resource_size_t cxl_dpa_resource_start(struct cxl_endpoint_decoder *cxled) 312 { 313 resource_size_t base = -1; 314 315 down_read(&cxl_dpa_rwsem); 316 if (cxled->dpa_res) 317 base = cxled->dpa_res->start; 318 up_read(&cxl_dpa_rwsem); 319 320 return base; 321 } 322 323 int cxl_dpa_free(struct cxl_endpoint_decoder *cxled) 324 { 325 struct cxl_port *port = cxled_to_port(cxled); 326 struct device *dev = &cxled->cxld.dev; 327 int rc; 328 329 down_write(&cxl_dpa_rwsem); 330 if (!cxled->dpa_res) { 331 rc = 0; 332 goto out; 333 } 334 if (cxled->cxld.region) { 335 dev_dbg(dev, "decoder assigned to: %s\n", 336 dev_name(&cxled->cxld.region->dev)); 337 rc = -EBUSY; 338 goto out; 339 } 340 if (cxled->cxld.flags & CXL_DECODER_F_ENABLE) { 341 dev_dbg(dev, "decoder enabled\n"); 342 rc = -EBUSY; 343 goto out; 344 } 345 if (cxled->cxld.id != port->hdm_end) { 346 dev_dbg(dev, "expected decoder%d.%d\n", port->id, 347 port->hdm_end); 348 rc = -EBUSY; 349 goto out; 350 } 351 devm_cxl_dpa_release(cxled); 352 rc = 0; 353 out: 354 up_write(&cxl_dpa_rwsem); 355 return rc; 356 } 357 358 int cxl_dpa_set_mode(struct cxl_endpoint_decoder *cxled, 359 enum cxl_decoder_mode mode) 360 { 361 struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); 362 struct cxl_dev_state *cxlds = cxlmd->cxlds; 363 struct device *dev = &cxled->cxld.dev; 364 int rc; 365 366 switch (mode) { 367 case CXL_DECODER_RAM: 368 case CXL_DECODER_PMEM: 369 break; 370 default: 371 dev_dbg(dev, "unsupported mode: %d\n", mode); 372 return -EINVAL; 373 } 374 375 down_write(&cxl_dpa_rwsem); 376 if (cxled->cxld.flags & CXL_DECODER_F_ENABLE) { 377 rc = -EBUSY; 378 goto out; 379 } 380 381 /* 382 * Only allow modes that are supported by the current partition 383 * configuration 384 */ 385 if (mode == CXL_DECODER_PMEM && !resource_size(&cxlds->pmem_res)) { 386 dev_dbg(dev, "no available pmem capacity\n"); 387 rc = -ENXIO; 388 goto out; 389 } 390 if (mode == CXL_DECODER_RAM && !resource_size(&cxlds->ram_res)) { 391 dev_dbg(dev, "no available ram capacity\n"); 392 rc = -ENXIO; 393 goto out; 394 } 395 396 cxled->mode = mode; 397 rc = 0; 398 out: 399 up_write(&cxl_dpa_rwsem); 400 401 return rc; 402 } 403 404 int cxl_dpa_alloc(struct cxl_endpoint_decoder *cxled, unsigned long long size) 405 { 406 struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); 407 resource_size_t free_ram_start, free_pmem_start; 408 struct cxl_port *port = cxled_to_port(cxled); 409 struct cxl_dev_state *cxlds = cxlmd->cxlds; 410 struct device *dev = &cxled->cxld.dev; 411 resource_size_t start, avail, skip; 412 struct resource *p, *last; 413 int rc; 414 415 down_write(&cxl_dpa_rwsem); 416 if (cxled->cxld.region) { 417 dev_dbg(dev, "decoder attached to %s\n", 418 dev_name(&cxled->cxld.region->dev)); 419 rc = -EBUSY; 420 goto out; 421 } 422 423 if (cxled->cxld.flags & CXL_DECODER_F_ENABLE) { 424 dev_dbg(dev, "decoder enabled\n"); 425 rc = -EBUSY; 426 goto out; 427 } 428 429 for (p = cxlds->ram_res.child, last = NULL; p; p = p->sibling) 430 last = p; 431 if (last) 432 free_ram_start = last->end + 1; 433 else 434 free_ram_start = cxlds->ram_res.start; 435 436 for (p = cxlds->pmem_res.child, last = NULL; p; p = p->sibling) 437 last = p; 438 if (last) 439 free_pmem_start = last->end + 1; 440 else 441 free_pmem_start = cxlds->pmem_res.start; 442 443 if (cxled->mode == CXL_DECODER_RAM) { 444 start = free_ram_start; 445 avail = cxlds->ram_res.end - start + 1; 446 skip = 0; 447 } else if (cxled->mode == CXL_DECODER_PMEM) { 448 resource_size_t skip_start, skip_end; 449 450 start = free_pmem_start; 451 avail = cxlds->pmem_res.end - start + 1; 452 skip_start = free_ram_start; 453 454 /* 455 * If some pmem is already allocated, then that allocation 456 * already handled the skip. 457 */ 458 if (cxlds->pmem_res.child && 459 skip_start == cxlds->pmem_res.child->start) 460 skip_end = skip_start - 1; 461 else 462 skip_end = start - 1; 463 skip = skip_end - skip_start + 1; 464 } else { 465 dev_dbg(dev, "mode not set\n"); 466 rc = -EINVAL; 467 goto out; 468 } 469 470 if (size > avail) { 471 dev_dbg(dev, "%pa exceeds available %s capacity: %pa\n", &size, 472 cxled->mode == CXL_DECODER_RAM ? "ram" : "pmem", 473 &avail); 474 rc = -ENOSPC; 475 goto out; 476 } 477 478 rc = __cxl_dpa_reserve(cxled, start, size, skip); 479 out: 480 up_write(&cxl_dpa_rwsem); 481 482 if (rc) 483 return rc; 484 485 return devm_add_action_or_reset(&port->dev, cxl_dpa_release, cxled); 486 } 487 488 static void cxld_set_interleave(struct cxl_decoder *cxld, u32 *ctrl) 489 { 490 u16 eig; 491 u8 eiw; 492 493 /* 494 * Input validation ensures these warns never fire, but otherwise 495 * suppress unititalized variable usage warnings. 496 */ 497 if (WARN_ONCE(ways_to_eiw(cxld->interleave_ways, &eiw), 498 "invalid interleave_ways: %d\n", cxld->interleave_ways)) 499 return; 500 if (WARN_ONCE(granularity_to_eig(cxld->interleave_granularity, &eig), 501 "invalid interleave_granularity: %d\n", 502 cxld->interleave_granularity)) 503 return; 504 505 u32p_replace_bits(ctrl, eig, CXL_HDM_DECODER0_CTRL_IG_MASK); 506 u32p_replace_bits(ctrl, eiw, CXL_HDM_DECODER0_CTRL_IW_MASK); 507 *ctrl |= CXL_HDM_DECODER0_CTRL_COMMIT; 508 } 509 510 static void cxld_set_type(struct cxl_decoder *cxld, u32 *ctrl) 511 { 512 u32p_replace_bits(ctrl, !!(cxld->target_type == 3), 513 CXL_HDM_DECODER0_CTRL_TYPE); 514 } 515 516 static int cxlsd_set_targets(struct cxl_switch_decoder *cxlsd, u64 *tgt) 517 { 518 struct cxl_dport **t = &cxlsd->target[0]; 519 int ways = cxlsd->cxld.interleave_ways; 520 521 if (dev_WARN_ONCE(&cxlsd->cxld.dev, 522 ways > 8 || ways > cxlsd->nr_targets, 523 "ways: %d overflows targets: %d\n", ways, 524 cxlsd->nr_targets)) 525 return -ENXIO; 526 527 *tgt = FIELD_PREP(GENMASK(7, 0), t[0]->port_id); 528 if (ways > 1) 529 *tgt |= FIELD_PREP(GENMASK(15, 8), t[1]->port_id); 530 if (ways > 2) 531 *tgt |= FIELD_PREP(GENMASK(23, 16), t[2]->port_id); 532 if (ways > 3) 533 *tgt |= FIELD_PREP(GENMASK(31, 24), t[3]->port_id); 534 if (ways > 4) 535 *tgt |= FIELD_PREP(GENMASK_ULL(39, 32), t[4]->port_id); 536 if (ways > 5) 537 *tgt |= FIELD_PREP(GENMASK_ULL(47, 40), t[5]->port_id); 538 if (ways > 6) 539 *tgt |= FIELD_PREP(GENMASK_ULL(55, 48), t[6]->port_id); 540 if (ways > 7) 541 *tgt |= FIELD_PREP(GENMASK_ULL(63, 56), t[7]->port_id); 542 543 return 0; 544 } 545 546 /* 547 * Per CXL 2.0 8.2.5.12.20 Committing Decoder Programming, hardware must set 548 * committed or error within 10ms, but just be generous with 20ms to account for 549 * clock skew and other marginal behavior 550 */ 551 #define COMMIT_TIMEOUT_MS 20 552 static int cxld_await_commit(void __iomem *hdm, int id) 553 { 554 u32 ctrl; 555 int i; 556 557 for (i = 0; i < COMMIT_TIMEOUT_MS; i++) { 558 ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(id)); 559 if (FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMIT_ERROR, ctrl)) { 560 ctrl &= ~CXL_HDM_DECODER0_CTRL_COMMIT; 561 writel(ctrl, hdm + CXL_HDM_DECODER0_CTRL_OFFSET(id)); 562 return -EIO; 563 } 564 if (FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMITTED, ctrl)) 565 return 0; 566 fsleep(1000); 567 } 568 569 return -ETIMEDOUT; 570 } 571 572 static int cxl_decoder_commit(struct cxl_decoder *cxld) 573 { 574 struct cxl_port *port = to_cxl_port(cxld->dev.parent); 575 struct cxl_hdm *cxlhdm = dev_get_drvdata(&port->dev); 576 void __iomem *hdm = cxlhdm->regs.hdm_decoder; 577 int id = cxld->id, rc; 578 u64 base, size; 579 u32 ctrl; 580 581 if (cxld->flags & CXL_DECODER_F_ENABLE) 582 return 0; 583 584 if (port->commit_end + 1 != id) { 585 dev_dbg(&port->dev, 586 "%s: out of order commit, expected decoder%d.%d\n", 587 dev_name(&cxld->dev), port->id, port->commit_end + 1); 588 return -EBUSY; 589 } 590 591 down_read(&cxl_dpa_rwsem); 592 /* common decoder settings */ 593 ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(cxld->id)); 594 cxld_set_interleave(cxld, &ctrl); 595 cxld_set_type(cxld, &ctrl); 596 base = cxld->hpa_range.start; 597 size = range_len(&cxld->hpa_range); 598 599 writel(upper_32_bits(base), hdm + CXL_HDM_DECODER0_BASE_HIGH_OFFSET(id)); 600 writel(lower_32_bits(base), hdm + CXL_HDM_DECODER0_BASE_LOW_OFFSET(id)); 601 writel(upper_32_bits(size), hdm + CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(id)); 602 writel(lower_32_bits(size), hdm + CXL_HDM_DECODER0_SIZE_LOW_OFFSET(id)); 603 604 if (is_switch_decoder(&cxld->dev)) { 605 struct cxl_switch_decoder *cxlsd = 606 to_cxl_switch_decoder(&cxld->dev); 607 void __iomem *tl_hi = hdm + CXL_HDM_DECODER0_TL_HIGH(id); 608 void __iomem *tl_lo = hdm + CXL_HDM_DECODER0_TL_LOW(id); 609 u64 targets; 610 611 rc = cxlsd_set_targets(cxlsd, &targets); 612 if (rc) { 613 dev_dbg(&port->dev, "%s: target configuration error\n", 614 dev_name(&cxld->dev)); 615 goto err; 616 } 617 618 writel(upper_32_bits(targets), tl_hi); 619 writel(lower_32_bits(targets), tl_lo); 620 } else { 621 struct cxl_endpoint_decoder *cxled = 622 to_cxl_endpoint_decoder(&cxld->dev); 623 void __iomem *sk_hi = hdm + CXL_HDM_DECODER0_SKIP_HIGH(id); 624 void __iomem *sk_lo = hdm + CXL_HDM_DECODER0_SKIP_LOW(id); 625 626 writel(upper_32_bits(cxled->skip), sk_hi); 627 writel(lower_32_bits(cxled->skip), sk_lo); 628 } 629 630 writel(ctrl, hdm + CXL_HDM_DECODER0_CTRL_OFFSET(id)); 631 up_read(&cxl_dpa_rwsem); 632 633 port->commit_end++; 634 rc = cxld_await_commit(hdm, cxld->id); 635 err: 636 if (rc) { 637 dev_dbg(&port->dev, "%s: error %d committing decoder\n", 638 dev_name(&cxld->dev), rc); 639 cxld->reset(cxld); 640 return rc; 641 } 642 cxld->flags |= CXL_DECODER_F_ENABLE; 643 644 return 0; 645 } 646 647 static int cxl_decoder_reset(struct cxl_decoder *cxld) 648 { 649 struct cxl_port *port = to_cxl_port(cxld->dev.parent); 650 struct cxl_hdm *cxlhdm = dev_get_drvdata(&port->dev); 651 void __iomem *hdm = cxlhdm->regs.hdm_decoder; 652 int id = cxld->id; 653 u32 ctrl; 654 655 if ((cxld->flags & CXL_DECODER_F_ENABLE) == 0) 656 return 0; 657 658 if (port->commit_end != id) { 659 dev_dbg(&port->dev, 660 "%s: out of order reset, expected decoder%d.%d\n", 661 dev_name(&cxld->dev), port->id, port->commit_end); 662 return -EBUSY; 663 } 664 665 down_read(&cxl_dpa_rwsem); 666 ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(id)); 667 ctrl &= ~CXL_HDM_DECODER0_CTRL_COMMIT; 668 writel(ctrl, hdm + CXL_HDM_DECODER0_CTRL_OFFSET(id)); 669 670 writel(0, hdm + CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(id)); 671 writel(0, hdm + CXL_HDM_DECODER0_SIZE_LOW_OFFSET(id)); 672 writel(0, hdm + CXL_HDM_DECODER0_BASE_HIGH_OFFSET(id)); 673 writel(0, hdm + CXL_HDM_DECODER0_BASE_LOW_OFFSET(id)); 674 up_read(&cxl_dpa_rwsem); 675 676 port->commit_end--; 677 cxld->flags &= ~CXL_DECODER_F_ENABLE; 678 679 return 0; 680 } 681 682 static int init_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld, 683 int *target_map, void __iomem *hdm, int which, 684 u64 *dpa_base) 685 { 686 struct cxl_endpoint_decoder *cxled = NULL; 687 u64 size, base, skip, dpa_size; 688 bool committed; 689 u32 remainder; 690 int i, rc; 691 u32 ctrl; 692 union { 693 u64 value; 694 unsigned char target_id[8]; 695 } target_list; 696 697 if (is_endpoint_decoder(&cxld->dev)) 698 cxled = to_cxl_endpoint_decoder(&cxld->dev); 699 700 ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(which)); 701 base = ioread64_hi_lo(hdm + CXL_HDM_DECODER0_BASE_LOW_OFFSET(which)); 702 size = ioread64_hi_lo(hdm + CXL_HDM_DECODER0_SIZE_LOW_OFFSET(which)); 703 committed = !!(ctrl & CXL_HDM_DECODER0_CTRL_COMMITTED); 704 cxld->commit = cxl_decoder_commit; 705 cxld->reset = cxl_decoder_reset; 706 707 if (!committed) 708 size = 0; 709 if (base == U64_MAX || size == U64_MAX) { 710 dev_warn(&port->dev, "decoder%d.%d: Invalid resource range\n", 711 port->id, cxld->id); 712 return -ENXIO; 713 } 714 715 cxld->hpa_range = (struct range) { 716 .start = base, 717 .end = base + size - 1, 718 }; 719 720 /* decoders are enabled if committed */ 721 if (committed) { 722 cxld->flags |= CXL_DECODER_F_ENABLE; 723 if (ctrl & CXL_HDM_DECODER0_CTRL_LOCK) 724 cxld->flags |= CXL_DECODER_F_LOCK; 725 if (FIELD_GET(CXL_HDM_DECODER0_CTRL_TYPE, ctrl)) 726 cxld->target_type = CXL_DECODER_EXPANDER; 727 else 728 cxld->target_type = CXL_DECODER_ACCELERATOR; 729 if (cxld->id != port->commit_end + 1) { 730 dev_warn(&port->dev, 731 "decoder%d.%d: Committed out of order\n", 732 port->id, cxld->id); 733 return -ENXIO; 734 } 735 port->commit_end = cxld->id; 736 } else { 737 /* unless / until type-2 drivers arrive, assume type-3 */ 738 if (FIELD_GET(CXL_HDM_DECODER0_CTRL_TYPE, ctrl) == 0) { 739 ctrl |= CXL_HDM_DECODER0_CTRL_TYPE; 740 writel(ctrl, hdm + CXL_HDM_DECODER0_CTRL_OFFSET(which)); 741 } 742 cxld->target_type = CXL_DECODER_EXPANDER; 743 } 744 rc = eiw_to_ways(FIELD_GET(CXL_HDM_DECODER0_CTRL_IW_MASK, ctrl), 745 &cxld->interleave_ways); 746 if (rc) { 747 dev_warn(&port->dev, 748 "decoder%d.%d: Invalid interleave ways (ctrl: %#x)\n", 749 port->id, cxld->id, ctrl); 750 return rc; 751 } 752 rc = eig_to_granularity(FIELD_GET(CXL_HDM_DECODER0_CTRL_IG_MASK, ctrl), 753 &cxld->interleave_granularity); 754 if (rc) 755 return rc; 756 757 if (!cxled) { 758 target_list.value = 759 ioread64_hi_lo(hdm + CXL_HDM_DECODER0_TL_LOW(which)); 760 for (i = 0; i < cxld->interleave_ways; i++) 761 target_map[i] = target_list.target_id[i]; 762 763 return 0; 764 } 765 766 if (!committed) 767 return 0; 768 769 dpa_size = div_u64_rem(size, cxld->interleave_ways, &remainder); 770 if (remainder) { 771 dev_err(&port->dev, 772 "decoder%d.%d: invalid committed configuration size: %#llx ways: %d\n", 773 port->id, cxld->id, size, cxld->interleave_ways); 774 return -ENXIO; 775 } 776 skip = ioread64_hi_lo(hdm + CXL_HDM_DECODER0_SKIP_LOW(which)); 777 rc = devm_cxl_dpa_reserve(cxled, *dpa_base + skip, dpa_size, skip); 778 if (rc) { 779 dev_err(&port->dev, 780 "decoder%d.%d: Failed to reserve DPA range %#llx - %#llx\n (%d)", 781 port->id, cxld->id, *dpa_base, 782 *dpa_base + dpa_size + skip - 1, rc); 783 return rc; 784 } 785 *dpa_base += dpa_size + skip; 786 return 0; 787 } 788 789 /** 790 * devm_cxl_enumerate_decoders - add decoder objects per HDM register set 791 * @cxlhdm: Structure to populate with HDM capabilities 792 */ 793 int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm) 794 { 795 void __iomem *hdm = cxlhdm->regs.hdm_decoder; 796 struct cxl_port *port = cxlhdm->port; 797 int i, committed; 798 u64 dpa_base = 0; 799 u32 ctrl; 800 801 /* 802 * Since the register resource was recently claimed via request_region() 803 * be careful about trusting the "not-committed" status until the commit 804 * timeout has elapsed. The commit timeout is 10ms (CXL 2.0 805 * 8.2.5.12.20), but double it to be tolerant of any clock skew between 806 * host and target. 807 */ 808 for (i = 0, committed = 0; i < cxlhdm->decoder_count; i++) { 809 ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(i)); 810 if (ctrl & CXL_HDM_DECODER0_CTRL_COMMITTED) 811 committed++; 812 } 813 814 /* ensure that future checks of committed can be trusted */ 815 if (committed != cxlhdm->decoder_count) 816 msleep(20); 817 818 for (i = 0; i < cxlhdm->decoder_count; i++) { 819 int target_map[CXL_DECODER_MAX_INTERLEAVE] = { 0 }; 820 int rc, target_count = cxlhdm->target_count; 821 struct cxl_decoder *cxld; 822 823 if (is_cxl_endpoint(port)) { 824 struct cxl_endpoint_decoder *cxled; 825 826 cxled = cxl_endpoint_decoder_alloc(port); 827 if (IS_ERR(cxled)) { 828 dev_warn(&port->dev, 829 "Failed to allocate the decoder\n"); 830 return PTR_ERR(cxled); 831 } 832 cxld = &cxled->cxld; 833 } else { 834 struct cxl_switch_decoder *cxlsd; 835 836 cxlsd = cxl_switch_decoder_alloc(port, target_count); 837 if (IS_ERR(cxlsd)) { 838 dev_warn(&port->dev, 839 "Failed to allocate the decoder\n"); 840 return PTR_ERR(cxlsd); 841 } 842 cxld = &cxlsd->cxld; 843 } 844 845 rc = init_hdm_decoder(port, cxld, target_map, hdm, i, &dpa_base); 846 if (rc) { 847 put_device(&cxld->dev); 848 return rc; 849 } 850 rc = add_hdm_decoder(port, cxld, target_map); 851 if (rc) { 852 dev_warn(&port->dev, 853 "Failed to add decoder to port\n"); 854 return rc; 855 } 856 } 857 858 return 0; 859 } 860 EXPORT_SYMBOL_NS_GPL(devm_cxl_enumerate_decoders, CXL); 861