1 // SPDX-License-Identifier: GPL-2.0-only 2 /* Copyright(c) 2022 Intel Corporation. All rights reserved. */ 3 #include <linux/seq_file.h> 4 #include <linux/device.h> 5 #include <linux/delay.h> 6 7 #include "cxlmem.h" 8 #include "core.h" 9 10 /** 11 * DOC: cxl core hdm 12 * 13 * Compute Express Link Host Managed Device Memory, starting with the 14 * CXL 2.0 specification, is managed by an array of HDM Decoder register 15 * instances per CXL port and per CXL endpoint. Define common helpers 16 * for enumerating these registers and capabilities. 17 */ 18 19 DECLARE_RWSEM(cxl_dpa_rwsem); 20 21 static int add_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld, 22 int *target_map) 23 { 24 int rc; 25 26 rc = cxl_decoder_add_locked(cxld, target_map); 27 if (rc) { 28 put_device(&cxld->dev); 29 dev_err(&port->dev, "Failed to add decoder\n"); 30 return rc; 31 } 32 33 rc = cxl_decoder_autoremove(&port->dev, cxld); 34 if (rc) 35 return rc; 36 37 dev_dbg(&cxld->dev, "Added to port %s\n", dev_name(&port->dev)); 38 39 return 0; 40 } 41 42 /* 43 * Per the CXL specification (8.2.5.12 CXL HDM Decoder Capability Structure) 44 * single ported host-bridges need not publish a decoder capability when a 45 * passthrough decode can be assumed, i.e. all transactions that the uport sees 46 * are claimed and passed to the single dport. Disable the range until the first 47 * CXL region is enumerated / activated. 48 */ 49 int devm_cxl_add_passthrough_decoder(struct cxl_port *port) 50 { 51 struct cxl_switch_decoder *cxlsd; 52 struct cxl_dport *dport = NULL; 53 int single_port_map[1]; 54 unsigned long index; 55 56 cxlsd = cxl_switch_decoder_alloc(port, 1); 57 if (IS_ERR(cxlsd)) 58 return PTR_ERR(cxlsd); 59 60 device_lock_assert(&port->dev); 61 62 xa_for_each(&port->dports, index, dport) 63 break; 64 single_port_map[0] = dport->port_id; 65 66 return add_hdm_decoder(port, &cxlsd->cxld, single_port_map); 67 } 68 EXPORT_SYMBOL_NS_GPL(devm_cxl_add_passthrough_decoder, CXL); 69 70 static void parse_hdm_decoder_caps(struct cxl_hdm *cxlhdm) 71 { 72 u32 hdm_cap; 73 74 hdm_cap = readl(cxlhdm->regs.hdm_decoder + CXL_HDM_DECODER_CAP_OFFSET); 75 cxlhdm->decoder_count = cxl_hdm_decoder_count(hdm_cap); 76 cxlhdm->target_count = 77 FIELD_GET(CXL_HDM_DECODER_TARGET_COUNT_MASK, hdm_cap); 78 if (FIELD_GET(CXL_HDM_DECODER_INTERLEAVE_11_8, hdm_cap)) 79 cxlhdm->interleave_mask |= GENMASK(11, 8); 80 if (FIELD_GET(CXL_HDM_DECODER_INTERLEAVE_14_12, hdm_cap)) 81 cxlhdm->interleave_mask |= GENMASK(14, 12); 82 } 83 84 static int map_hdm_decoder_regs(struct cxl_port *port, void __iomem *crb, 85 struct cxl_component_regs *regs) 86 { 87 struct cxl_register_map map = { 88 .resource = port->component_reg_phys, 89 .base = crb, 90 .max_size = CXL_COMPONENT_REG_BLOCK_SIZE, 91 }; 92 93 cxl_probe_component_regs(&port->dev, crb, &map.component_map); 94 if (!map.component_map.hdm_decoder.valid) { 95 dev_dbg(&port->dev, "HDM decoder registers not implemented\n"); 96 /* unique error code to indicate no HDM decoder capability */ 97 return -ENODEV; 98 } 99 100 return cxl_map_component_regs(&port->dev, regs, &map, 101 BIT(CXL_CM_CAP_CAP_ID_HDM)); 102 } 103 104 static bool should_emulate_decoders(struct cxl_endpoint_dvsec_info *info) 105 { 106 struct cxl_hdm *cxlhdm; 107 void __iomem *hdm; 108 u32 ctrl; 109 int i; 110 111 if (!info) 112 return false; 113 114 cxlhdm = dev_get_drvdata(&info->port->dev); 115 hdm = cxlhdm->regs.hdm_decoder; 116 117 if (!hdm) 118 return true; 119 120 /* 121 * If HDM decoders are present and the driver is in control of 122 * Mem_Enable skip DVSEC based emulation 123 */ 124 if (!info->mem_enabled) 125 return false; 126 127 /* 128 * If any decoders are committed already, there should not be any 129 * emulated DVSEC decoders. 130 */ 131 for (i = 0; i < cxlhdm->decoder_count; i++) { 132 ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(i)); 133 dev_dbg(&info->port->dev, 134 "decoder%d.%d: committed: %ld base: %#x_%.8x size: %#x_%.8x\n", 135 info->port->id, i, 136 FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMITTED, ctrl), 137 readl(hdm + CXL_HDM_DECODER0_BASE_HIGH_OFFSET(i)), 138 readl(hdm + CXL_HDM_DECODER0_BASE_LOW_OFFSET(i)), 139 readl(hdm + CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(i)), 140 readl(hdm + CXL_HDM_DECODER0_SIZE_LOW_OFFSET(i))); 141 if (FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMITTED, ctrl)) 142 return false; 143 } 144 145 return true; 146 } 147 148 /** 149 * devm_cxl_setup_hdm - map HDM decoder component registers 150 * @port: cxl_port to map 151 * @info: cached DVSEC range register info 152 */ 153 struct cxl_hdm *devm_cxl_setup_hdm(struct cxl_port *port, 154 struct cxl_endpoint_dvsec_info *info) 155 { 156 struct device *dev = &port->dev; 157 struct cxl_hdm *cxlhdm; 158 void __iomem *crb; 159 int rc; 160 161 cxlhdm = devm_kzalloc(dev, sizeof(*cxlhdm), GFP_KERNEL); 162 if (!cxlhdm) 163 return ERR_PTR(-ENOMEM); 164 cxlhdm->port = port; 165 dev_set_drvdata(dev, cxlhdm); 166 167 crb = ioremap(port->component_reg_phys, CXL_COMPONENT_REG_BLOCK_SIZE); 168 if (!crb && info && info->mem_enabled) { 169 cxlhdm->decoder_count = info->ranges; 170 return cxlhdm; 171 } else if (!crb) { 172 dev_err(dev, "No component registers mapped\n"); 173 return ERR_PTR(-ENXIO); 174 } 175 176 rc = map_hdm_decoder_regs(port, crb, &cxlhdm->regs); 177 iounmap(crb); 178 if (rc) 179 return ERR_PTR(rc); 180 181 parse_hdm_decoder_caps(cxlhdm); 182 if (cxlhdm->decoder_count == 0) { 183 dev_err(dev, "Spec violation. Caps invalid\n"); 184 return ERR_PTR(-ENXIO); 185 } 186 187 /* 188 * Now that the hdm capability is parsed, decide if range 189 * register emulation is needed and fixup cxlhdm accordingly. 190 */ 191 if (should_emulate_decoders(info)) { 192 dev_dbg(dev, "Fallback map %d range register%s\n", info->ranges, 193 info->ranges > 1 ? "s" : ""); 194 cxlhdm->decoder_count = info->ranges; 195 } 196 197 return cxlhdm; 198 } 199 EXPORT_SYMBOL_NS_GPL(devm_cxl_setup_hdm, CXL); 200 201 static void __cxl_dpa_debug(struct seq_file *file, struct resource *r, int depth) 202 { 203 unsigned long long start = r->start, end = r->end; 204 205 seq_printf(file, "%*s%08llx-%08llx : %s\n", depth * 2, "", start, end, 206 r->name); 207 } 208 209 void cxl_dpa_debug(struct seq_file *file, struct cxl_dev_state *cxlds) 210 { 211 struct resource *p1, *p2; 212 213 down_read(&cxl_dpa_rwsem); 214 for (p1 = cxlds->dpa_res.child; p1; p1 = p1->sibling) { 215 __cxl_dpa_debug(file, p1, 0); 216 for (p2 = p1->child; p2; p2 = p2->sibling) 217 __cxl_dpa_debug(file, p2, 1); 218 } 219 up_read(&cxl_dpa_rwsem); 220 } 221 EXPORT_SYMBOL_NS_GPL(cxl_dpa_debug, CXL); 222 223 /* 224 * Must be called in a context that synchronizes against this decoder's 225 * port ->remove() callback (like an endpoint decoder sysfs attribute) 226 */ 227 static void __cxl_dpa_release(struct cxl_endpoint_decoder *cxled) 228 { 229 struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); 230 struct cxl_port *port = cxled_to_port(cxled); 231 struct cxl_dev_state *cxlds = cxlmd->cxlds; 232 struct resource *res = cxled->dpa_res; 233 resource_size_t skip_start; 234 235 lockdep_assert_held_write(&cxl_dpa_rwsem); 236 237 /* save @skip_start, before @res is released */ 238 skip_start = res->start - cxled->skip; 239 __release_region(&cxlds->dpa_res, res->start, resource_size(res)); 240 if (cxled->skip) 241 __release_region(&cxlds->dpa_res, skip_start, cxled->skip); 242 cxled->skip = 0; 243 cxled->dpa_res = NULL; 244 put_device(&cxled->cxld.dev); 245 port->hdm_end--; 246 } 247 248 static void cxl_dpa_release(void *cxled) 249 { 250 down_write(&cxl_dpa_rwsem); 251 __cxl_dpa_release(cxled); 252 up_write(&cxl_dpa_rwsem); 253 } 254 255 /* 256 * Must be called from context that will not race port device 257 * unregistration, like decoder sysfs attribute methods 258 */ 259 static void devm_cxl_dpa_release(struct cxl_endpoint_decoder *cxled) 260 { 261 struct cxl_port *port = cxled_to_port(cxled); 262 263 lockdep_assert_held_write(&cxl_dpa_rwsem); 264 devm_remove_action(&port->dev, cxl_dpa_release, cxled); 265 __cxl_dpa_release(cxled); 266 } 267 268 static int __cxl_dpa_reserve(struct cxl_endpoint_decoder *cxled, 269 resource_size_t base, resource_size_t len, 270 resource_size_t skipped) 271 { 272 struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); 273 struct cxl_port *port = cxled_to_port(cxled); 274 struct cxl_dev_state *cxlds = cxlmd->cxlds; 275 struct device *dev = &port->dev; 276 struct resource *res; 277 278 lockdep_assert_held_write(&cxl_dpa_rwsem); 279 280 if (!len) { 281 dev_warn(dev, "decoder%d.%d: empty reservation attempted\n", 282 port->id, cxled->cxld.id); 283 return -EINVAL; 284 } 285 286 if (cxled->dpa_res) { 287 dev_dbg(dev, "decoder%d.%d: existing allocation %pr assigned\n", 288 port->id, cxled->cxld.id, cxled->dpa_res); 289 return -EBUSY; 290 } 291 292 if (port->hdm_end + 1 != cxled->cxld.id) { 293 /* 294 * Assumes alloc and commit order is always in hardware instance 295 * order per expectations from 8.2.5.12.20 Committing Decoder 296 * Programming that enforce decoder[m] committed before 297 * decoder[m+1] commit start. 298 */ 299 dev_dbg(dev, "decoder%d.%d: expected decoder%d.%d\n", port->id, 300 cxled->cxld.id, port->id, port->hdm_end + 1); 301 return -EBUSY; 302 } 303 304 if (skipped) { 305 res = __request_region(&cxlds->dpa_res, base - skipped, skipped, 306 dev_name(&cxled->cxld.dev), 0); 307 if (!res) { 308 dev_dbg(dev, 309 "decoder%d.%d: failed to reserve skipped space\n", 310 port->id, cxled->cxld.id); 311 return -EBUSY; 312 } 313 } 314 res = __request_region(&cxlds->dpa_res, base, len, 315 dev_name(&cxled->cxld.dev), 0); 316 if (!res) { 317 dev_dbg(dev, "decoder%d.%d: failed to reserve allocation\n", 318 port->id, cxled->cxld.id); 319 if (skipped) 320 __release_region(&cxlds->dpa_res, base - skipped, 321 skipped); 322 return -EBUSY; 323 } 324 cxled->dpa_res = res; 325 cxled->skip = skipped; 326 327 if (resource_contains(&cxlds->pmem_res, res)) 328 cxled->mode = CXL_DECODER_PMEM; 329 else if (resource_contains(&cxlds->ram_res, res)) 330 cxled->mode = CXL_DECODER_RAM; 331 else { 332 dev_dbg(dev, "decoder%d.%d: %pr mixed\n", port->id, 333 cxled->cxld.id, cxled->dpa_res); 334 cxled->mode = CXL_DECODER_MIXED; 335 } 336 337 port->hdm_end++; 338 get_device(&cxled->cxld.dev); 339 return 0; 340 } 341 342 int devm_cxl_dpa_reserve(struct cxl_endpoint_decoder *cxled, 343 resource_size_t base, resource_size_t len, 344 resource_size_t skipped) 345 { 346 struct cxl_port *port = cxled_to_port(cxled); 347 int rc; 348 349 down_write(&cxl_dpa_rwsem); 350 rc = __cxl_dpa_reserve(cxled, base, len, skipped); 351 up_write(&cxl_dpa_rwsem); 352 353 if (rc) 354 return rc; 355 356 return devm_add_action_or_reset(&port->dev, cxl_dpa_release, cxled); 357 } 358 EXPORT_SYMBOL_NS_GPL(devm_cxl_dpa_reserve, CXL); 359 360 resource_size_t cxl_dpa_size(struct cxl_endpoint_decoder *cxled) 361 { 362 resource_size_t size = 0; 363 364 down_read(&cxl_dpa_rwsem); 365 if (cxled->dpa_res) 366 size = resource_size(cxled->dpa_res); 367 up_read(&cxl_dpa_rwsem); 368 369 return size; 370 } 371 372 resource_size_t cxl_dpa_resource_start(struct cxl_endpoint_decoder *cxled) 373 { 374 resource_size_t base = -1; 375 376 down_read(&cxl_dpa_rwsem); 377 if (cxled->dpa_res) 378 base = cxled->dpa_res->start; 379 up_read(&cxl_dpa_rwsem); 380 381 return base; 382 } 383 384 int cxl_dpa_free(struct cxl_endpoint_decoder *cxled) 385 { 386 struct cxl_port *port = cxled_to_port(cxled); 387 struct device *dev = &cxled->cxld.dev; 388 int rc; 389 390 down_write(&cxl_dpa_rwsem); 391 if (!cxled->dpa_res) { 392 rc = 0; 393 goto out; 394 } 395 if (cxled->cxld.region) { 396 dev_dbg(dev, "decoder assigned to: %s\n", 397 dev_name(&cxled->cxld.region->dev)); 398 rc = -EBUSY; 399 goto out; 400 } 401 if (cxled->cxld.flags & CXL_DECODER_F_ENABLE) { 402 dev_dbg(dev, "decoder enabled\n"); 403 rc = -EBUSY; 404 goto out; 405 } 406 if (cxled->cxld.id != port->hdm_end) { 407 dev_dbg(dev, "expected decoder%d.%d\n", port->id, 408 port->hdm_end); 409 rc = -EBUSY; 410 goto out; 411 } 412 devm_cxl_dpa_release(cxled); 413 rc = 0; 414 out: 415 up_write(&cxl_dpa_rwsem); 416 return rc; 417 } 418 419 int cxl_dpa_set_mode(struct cxl_endpoint_decoder *cxled, 420 enum cxl_decoder_mode mode) 421 { 422 struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); 423 struct cxl_dev_state *cxlds = cxlmd->cxlds; 424 struct device *dev = &cxled->cxld.dev; 425 int rc; 426 427 switch (mode) { 428 case CXL_DECODER_RAM: 429 case CXL_DECODER_PMEM: 430 break; 431 default: 432 dev_dbg(dev, "unsupported mode: %d\n", mode); 433 return -EINVAL; 434 } 435 436 down_write(&cxl_dpa_rwsem); 437 if (cxled->cxld.flags & CXL_DECODER_F_ENABLE) { 438 rc = -EBUSY; 439 goto out; 440 } 441 442 /* 443 * Only allow modes that are supported by the current partition 444 * configuration 445 */ 446 if (mode == CXL_DECODER_PMEM && !resource_size(&cxlds->pmem_res)) { 447 dev_dbg(dev, "no available pmem capacity\n"); 448 rc = -ENXIO; 449 goto out; 450 } 451 if (mode == CXL_DECODER_RAM && !resource_size(&cxlds->ram_res)) { 452 dev_dbg(dev, "no available ram capacity\n"); 453 rc = -ENXIO; 454 goto out; 455 } 456 457 cxled->mode = mode; 458 rc = 0; 459 out: 460 up_write(&cxl_dpa_rwsem); 461 462 return rc; 463 } 464 465 int cxl_dpa_alloc(struct cxl_endpoint_decoder *cxled, unsigned long long size) 466 { 467 struct cxl_memdev *cxlmd = cxled_to_memdev(cxled); 468 resource_size_t free_ram_start, free_pmem_start; 469 struct cxl_port *port = cxled_to_port(cxled); 470 struct cxl_dev_state *cxlds = cxlmd->cxlds; 471 struct device *dev = &cxled->cxld.dev; 472 resource_size_t start, avail, skip; 473 struct resource *p, *last; 474 int rc; 475 476 down_write(&cxl_dpa_rwsem); 477 if (cxled->cxld.region) { 478 dev_dbg(dev, "decoder attached to %s\n", 479 dev_name(&cxled->cxld.region->dev)); 480 rc = -EBUSY; 481 goto out; 482 } 483 484 if (cxled->cxld.flags & CXL_DECODER_F_ENABLE) { 485 dev_dbg(dev, "decoder enabled\n"); 486 rc = -EBUSY; 487 goto out; 488 } 489 490 for (p = cxlds->ram_res.child, last = NULL; p; p = p->sibling) 491 last = p; 492 if (last) 493 free_ram_start = last->end + 1; 494 else 495 free_ram_start = cxlds->ram_res.start; 496 497 for (p = cxlds->pmem_res.child, last = NULL; p; p = p->sibling) 498 last = p; 499 if (last) 500 free_pmem_start = last->end + 1; 501 else 502 free_pmem_start = cxlds->pmem_res.start; 503 504 if (cxled->mode == CXL_DECODER_RAM) { 505 start = free_ram_start; 506 avail = cxlds->ram_res.end - start + 1; 507 skip = 0; 508 } else if (cxled->mode == CXL_DECODER_PMEM) { 509 resource_size_t skip_start, skip_end; 510 511 start = free_pmem_start; 512 avail = cxlds->pmem_res.end - start + 1; 513 skip_start = free_ram_start; 514 515 /* 516 * If some pmem is already allocated, then that allocation 517 * already handled the skip. 518 */ 519 if (cxlds->pmem_res.child && 520 skip_start == cxlds->pmem_res.child->start) 521 skip_end = skip_start - 1; 522 else 523 skip_end = start - 1; 524 skip = skip_end - skip_start + 1; 525 } else { 526 dev_dbg(dev, "mode not set\n"); 527 rc = -EINVAL; 528 goto out; 529 } 530 531 if (size > avail) { 532 dev_dbg(dev, "%pa exceeds available %s capacity: %pa\n", &size, 533 cxled->mode == CXL_DECODER_RAM ? "ram" : "pmem", 534 &avail); 535 rc = -ENOSPC; 536 goto out; 537 } 538 539 rc = __cxl_dpa_reserve(cxled, start, size, skip); 540 out: 541 up_write(&cxl_dpa_rwsem); 542 543 if (rc) 544 return rc; 545 546 return devm_add_action_or_reset(&port->dev, cxl_dpa_release, cxled); 547 } 548 549 static void cxld_set_interleave(struct cxl_decoder *cxld, u32 *ctrl) 550 { 551 u16 eig; 552 u8 eiw; 553 554 /* 555 * Input validation ensures these warns never fire, but otherwise 556 * suppress unititalized variable usage warnings. 557 */ 558 if (WARN_ONCE(ways_to_eiw(cxld->interleave_ways, &eiw), 559 "invalid interleave_ways: %d\n", cxld->interleave_ways)) 560 return; 561 if (WARN_ONCE(granularity_to_eig(cxld->interleave_granularity, &eig), 562 "invalid interleave_granularity: %d\n", 563 cxld->interleave_granularity)) 564 return; 565 566 u32p_replace_bits(ctrl, eig, CXL_HDM_DECODER0_CTRL_IG_MASK); 567 u32p_replace_bits(ctrl, eiw, CXL_HDM_DECODER0_CTRL_IW_MASK); 568 *ctrl |= CXL_HDM_DECODER0_CTRL_COMMIT; 569 } 570 571 static void cxld_set_type(struct cxl_decoder *cxld, u32 *ctrl) 572 { 573 u32p_replace_bits(ctrl, 574 !!(cxld->target_type == CXL_DECODER_HOSTONLYMEM), 575 CXL_HDM_DECODER0_CTRL_TYPE); 576 } 577 578 static int cxlsd_set_targets(struct cxl_switch_decoder *cxlsd, u64 *tgt) 579 { 580 struct cxl_dport **t = &cxlsd->target[0]; 581 int ways = cxlsd->cxld.interleave_ways; 582 583 if (dev_WARN_ONCE(&cxlsd->cxld.dev, 584 ways > 8 || ways > cxlsd->nr_targets, 585 "ways: %d overflows targets: %d\n", ways, 586 cxlsd->nr_targets)) 587 return -ENXIO; 588 589 *tgt = FIELD_PREP(GENMASK(7, 0), t[0]->port_id); 590 if (ways > 1) 591 *tgt |= FIELD_PREP(GENMASK(15, 8), t[1]->port_id); 592 if (ways > 2) 593 *tgt |= FIELD_PREP(GENMASK(23, 16), t[2]->port_id); 594 if (ways > 3) 595 *tgt |= FIELD_PREP(GENMASK(31, 24), t[3]->port_id); 596 if (ways > 4) 597 *tgt |= FIELD_PREP(GENMASK_ULL(39, 32), t[4]->port_id); 598 if (ways > 5) 599 *tgt |= FIELD_PREP(GENMASK_ULL(47, 40), t[5]->port_id); 600 if (ways > 6) 601 *tgt |= FIELD_PREP(GENMASK_ULL(55, 48), t[6]->port_id); 602 if (ways > 7) 603 *tgt |= FIELD_PREP(GENMASK_ULL(63, 56), t[7]->port_id); 604 605 return 0; 606 } 607 608 /* 609 * Per CXL 2.0 8.2.5.12.20 Committing Decoder Programming, hardware must set 610 * committed or error within 10ms, but just be generous with 20ms to account for 611 * clock skew and other marginal behavior 612 */ 613 #define COMMIT_TIMEOUT_MS 20 614 static int cxld_await_commit(void __iomem *hdm, int id) 615 { 616 u32 ctrl; 617 int i; 618 619 for (i = 0; i < COMMIT_TIMEOUT_MS; i++) { 620 ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(id)); 621 if (FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMIT_ERROR, ctrl)) { 622 ctrl &= ~CXL_HDM_DECODER0_CTRL_COMMIT; 623 writel(ctrl, hdm + CXL_HDM_DECODER0_CTRL_OFFSET(id)); 624 return -EIO; 625 } 626 if (FIELD_GET(CXL_HDM_DECODER0_CTRL_COMMITTED, ctrl)) 627 return 0; 628 fsleep(1000); 629 } 630 631 return -ETIMEDOUT; 632 } 633 634 static int cxl_decoder_commit(struct cxl_decoder *cxld) 635 { 636 struct cxl_port *port = to_cxl_port(cxld->dev.parent); 637 struct cxl_hdm *cxlhdm = dev_get_drvdata(&port->dev); 638 void __iomem *hdm = cxlhdm->regs.hdm_decoder; 639 int id = cxld->id, rc; 640 u64 base, size; 641 u32 ctrl; 642 643 if (cxld->flags & CXL_DECODER_F_ENABLE) 644 return 0; 645 646 if (port->commit_end + 1 != id) { 647 dev_dbg(&port->dev, 648 "%s: out of order commit, expected decoder%d.%d\n", 649 dev_name(&cxld->dev), port->id, port->commit_end + 1); 650 return -EBUSY; 651 } 652 653 down_read(&cxl_dpa_rwsem); 654 /* common decoder settings */ 655 ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(cxld->id)); 656 cxld_set_interleave(cxld, &ctrl); 657 cxld_set_type(cxld, &ctrl); 658 base = cxld->hpa_range.start; 659 size = range_len(&cxld->hpa_range); 660 661 writel(upper_32_bits(base), hdm + CXL_HDM_DECODER0_BASE_HIGH_OFFSET(id)); 662 writel(lower_32_bits(base), hdm + CXL_HDM_DECODER0_BASE_LOW_OFFSET(id)); 663 writel(upper_32_bits(size), hdm + CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(id)); 664 writel(lower_32_bits(size), hdm + CXL_HDM_DECODER0_SIZE_LOW_OFFSET(id)); 665 666 if (is_switch_decoder(&cxld->dev)) { 667 struct cxl_switch_decoder *cxlsd = 668 to_cxl_switch_decoder(&cxld->dev); 669 void __iomem *tl_hi = hdm + CXL_HDM_DECODER0_TL_HIGH(id); 670 void __iomem *tl_lo = hdm + CXL_HDM_DECODER0_TL_LOW(id); 671 u64 targets; 672 673 rc = cxlsd_set_targets(cxlsd, &targets); 674 if (rc) { 675 dev_dbg(&port->dev, "%s: target configuration error\n", 676 dev_name(&cxld->dev)); 677 goto err; 678 } 679 680 writel(upper_32_bits(targets), tl_hi); 681 writel(lower_32_bits(targets), tl_lo); 682 } else { 683 struct cxl_endpoint_decoder *cxled = 684 to_cxl_endpoint_decoder(&cxld->dev); 685 void __iomem *sk_hi = hdm + CXL_HDM_DECODER0_SKIP_HIGH(id); 686 void __iomem *sk_lo = hdm + CXL_HDM_DECODER0_SKIP_LOW(id); 687 688 writel(upper_32_bits(cxled->skip), sk_hi); 689 writel(lower_32_bits(cxled->skip), sk_lo); 690 } 691 692 writel(ctrl, hdm + CXL_HDM_DECODER0_CTRL_OFFSET(id)); 693 up_read(&cxl_dpa_rwsem); 694 695 port->commit_end++; 696 rc = cxld_await_commit(hdm, cxld->id); 697 err: 698 if (rc) { 699 dev_dbg(&port->dev, "%s: error %d committing decoder\n", 700 dev_name(&cxld->dev), rc); 701 cxld->reset(cxld); 702 return rc; 703 } 704 cxld->flags |= CXL_DECODER_F_ENABLE; 705 706 return 0; 707 } 708 709 static int cxl_decoder_reset(struct cxl_decoder *cxld) 710 { 711 struct cxl_port *port = to_cxl_port(cxld->dev.parent); 712 struct cxl_hdm *cxlhdm = dev_get_drvdata(&port->dev); 713 void __iomem *hdm = cxlhdm->regs.hdm_decoder; 714 int id = cxld->id; 715 u32 ctrl; 716 717 if ((cxld->flags & CXL_DECODER_F_ENABLE) == 0) 718 return 0; 719 720 if (port->commit_end != id) { 721 dev_dbg(&port->dev, 722 "%s: out of order reset, expected decoder%d.%d\n", 723 dev_name(&cxld->dev), port->id, port->commit_end); 724 return -EBUSY; 725 } 726 727 down_read(&cxl_dpa_rwsem); 728 ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(id)); 729 ctrl &= ~CXL_HDM_DECODER0_CTRL_COMMIT; 730 writel(ctrl, hdm + CXL_HDM_DECODER0_CTRL_OFFSET(id)); 731 732 writel(0, hdm + CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(id)); 733 writel(0, hdm + CXL_HDM_DECODER0_SIZE_LOW_OFFSET(id)); 734 writel(0, hdm + CXL_HDM_DECODER0_BASE_HIGH_OFFSET(id)); 735 writel(0, hdm + CXL_HDM_DECODER0_BASE_LOW_OFFSET(id)); 736 up_read(&cxl_dpa_rwsem); 737 738 port->commit_end--; 739 cxld->flags &= ~CXL_DECODER_F_ENABLE; 740 741 /* Userspace is now responsible for reconfiguring this decoder */ 742 if (is_endpoint_decoder(&cxld->dev)) { 743 struct cxl_endpoint_decoder *cxled; 744 745 cxled = to_cxl_endpoint_decoder(&cxld->dev); 746 cxled->state = CXL_DECODER_STATE_MANUAL; 747 } 748 749 return 0; 750 } 751 752 static int cxl_setup_hdm_decoder_from_dvsec( 753 struct cxl_port *port, struct cxl_decoder *cxld, u64 *dpa_base, 754 int which, struct cxl_endpoint_dvsec_info *info) 755 { 756 struct cxl_endpoint_decoder *cxled; 757 u64 len; 758 int rc; 759 760 if (!is_cxl_endpoint(port)) 761 return -EOPNOTSUPP; 762 763 cxled = to_cxl_endpoint_decoder(&cxld->dev); 764 len = range_len(&info->dvsec_range[which]); 765 if (!len) 766 return -ENOENT; 767 768 cxld->target_type = CXL_DECODER_HOSTONLYMEM; 769 cxld->commit = NULL; 770 cxld->reset = NULL; 771 cxld->hpa_range = info->dvsec_range[which]; 772 773 /* 774 * Set the emulated decoder as locked pending additional support to 775 * change the range registers at run time. 776 */ 777 cxld->flags |= CXL_DECODER_F_ENABLE | CXL_DECODER_F_LOCK; 778 port->commit_end = cxld->id; 779 780 rc = devm_cxl_dpa_reserve(cxled, *dpa_base, len, 0); 781 if (rc) { 782 dev_err(&port->dev, 783 "decoder%d.%d: Failed to reserve DPA range %#llx - %#llx\n (%d)", 784 port->id, cxld->id, *dpa_base, *dpa_base + len - 1, rc); 785 return rc; 786 } 787 *dpa_base += len; 788 cxled->state = CXL_DECODER_STATE_AUTO; 789 790 return 0; 791 } 792 793 static int init_hdm_decoder(struct cxl_port *port, struct cxl_decoder *cxld, 794 int *target_map, void __iomem *hdm, int which, 795 u64 *dpa_base, struct cxl_endpoint_dvsec_info *info) 796 { 797 u64 size, base, skip, dpa_size, lo, hi; 798 struct cxl_endpoint_decoder *cxled; 799 bool committed; 800 u32 remainder; 801 int i, rc; 802 u32 ctrl; 803 union { 804 u64 value; 805 unsigned char target_id[8]; 806 } target_list; 807 808 if (should_emulate_decoders(info)) 809 return cxl_setup_hdm_decoder_from_dvsec(port, cxld, dpa_base, 810 which, info); 811 812 ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(which)); 813 lo = readl(hdm + CXL_HDM_DECODER0_BASE_LOW_OFFSET(which)); 814 hi = readl(hdm + CXL_HDM_DECODER0_BASE_HIGH_OFFSET(which)); 815 base = (hi << 32) + lo; 816 lo = readl(hdm + CXL_HDM_DECODER0_SIZE_LOW_OFFSET(which)); 817 hi = readl(hdm + CXL_HDM_DECODER0_SIZE_HIGH_OFFSET(which)); 818 size = (hi << 32) + lo; 819 committed = !!(ctrl & CXL_HDM_DECODER0_CTRL_COMMITTED); 820 cxld->commit = cxl_decoder_commit; 821 cxld->reset = cxl_decoder_reset; 822 823 if (!committed) 824 size = 0; 825 if (base == U64_MAX || size == U64_MAX) { 826 dev_warn(&port->dev, "decoder%d.%d: Invalid resource range\n", 827 port->id, cxld->id); 828 return -ENXIO; 829 } 830 831 cxld->hpa_range = (struct range) { 832 .start = base, 833 .end = base + size - 1, 834 }; 835 836 /* decoders are enabled if committed */ 837 if (committed) { 838 cxld->flags |= CXL_DECODER_F_ENABLE; 839 if (ctrl & CXL_HDM_DECODER0_CTRL_LOCK) 840 cxld->flags |= CXL_DECODER_F_LOCK; 841 if (FIELD_GET(CXL_HDM_DECODER0_CTRL_TYPE, ctrl)) 842 cxld->target_type = CXL_DECODER_HOSTONLYMEM; 843 else 844 cxld->target_type = CXL_DECODER_DEVMEM; 845 if (cxld->id != port->commit_end + 1) { 846 dev_warn(&port->dev, 847 "decoder%d.%d: Committed out of order\n", 848 port->id, cxld->id); 849 return -ENXIO; 850 } 851 852 if (size == 0) { 853 dev_warn(&port->dev, 854 "decoder%d.%d: Committed with zero size\n", 855 port->id, cxld->id); 856 return -ENXIO; 857 } 858 port->commit_end = cxld->id; 859 } else { 860 /* unless / until type-2 drivers arrive, assume type-3 */ 861 if (FIELD_GET(CXL_HDM_DECODER0_CTRL_TYPE, ctrl) == 0) { 862 ctrl |= CXL_HDM_DECODER0_CTRL_TYPE; 863 writel(ctrl, hdm + CXL_HDM_DECODER0_CTRL_OFFSET(which)); 864 } 865 cxld->target_type = CXL_DECODER_HOSTONLYMEM; 866 } 867 rc = eiw_to_ways(FIELD_GET(CXL_HDM_DECODER0_CTRL_IW_MASK, ctrl), 868 &cxld->interleave_ways); 869 if (rc) { 870 dev_warn(&port->dev, 871 "decoder%d.%d: Invalid interleave ways (ctrl: %#x)\n", 872 port->id, cxld->id, ctrl); 873 return rc; 874 } 875 rc = eig_to_granularity(FIELD_GET(CXL_HDM_DECODER0_CTRL_IG_MASK, ctrl), 876 &cxld->interleave_granularity); 877 if (rc) 878 return rc; 879 880 dev_dbg(&port->dev, "decoder%d.%d: range: %#llx-%#llx iw: %d ig: %d\n", 881 port->id, cxld->id, cxld->hpa_range.start, cxld->hpa_range.end, 882 cxld->interleave_ways, cxld->interleave_granularity); 883 884 if (!info) { 885 lo = readl(hdm + CXL_HDM_DECODER0_TL_LOW(which)); 886 hi = readl(hdm + CXL_HDM_DECODER0_TL_HIGH(which)); 887 target_list.value = (hi << 32) + lo; 888 for (i = 0; i < cxld->interleave_ways; i++) 889 target_map[i] = target_list.target_id[i]; 890 891 return 0; 892 } 893 894 if (!committed) 895 return 0; 896 897 dpa_size = div_u64_rem(size, cxld->interleave_ways, &remainder); 898 if (remainder) { 899 dev_err(&port->dev, 900 "decoder%d.%d: invalid committed configuration size: %#llx ways: %d\n", 901 port->id, cxld->id, size, cxld->interleave_ways); 902 return -ENXIO; 903 } 904 lo = readl(hdm + CXL_HDM_DECODER0_SKIP_LOW(which)); 905 hi = readl(hdm + CXL_HDM_DECODER0_SKIP_HIGH(which)); 906 skip = (hi << 32) + lo; 907 cxled = to_cxl_endpoint_decoder(&cxld->dev); 908 rc = devm_cxl_dpa_reserve(cxled, *dpa_base + skip, dpa_size, skip); 909 if (rc) { 910 dev_err(&port->dev, 911 "decoder%d.%d: Failed to reserve DPA range %#llx - %#llx\n (%d)", 912 port->id, cxld->id, *dpa_base, 913 *dpa_base + dpa_size + skip - 1, rc); 914 return rc; 915 } 916 *dpa_base += dpa_size + skip; 917 918 cxled->state = CXL_DECODER_STATE_AUTO; 919 920 return 0; 921 } 922 923 static void cxl_settle_decoders(struct cxl_hdm *cxlhdm) 924 { 925 void __iomem *hdm = cxlhdm->regs.hdm_decoder; 926 int committed, i; 927 u32 ctrl; 928 929 if (!hdm) 930 return; 931 932 /* 933 * Since the register resource was recently claimed via request_region() 934 * be careful about trusting the "not-committed" status until the commit 935 * timeout has elapsed. The commit timeout is 10ms (CXL 2.0 936 * 8.2.5.12.20), but double it to be tolerant of any clock skew between 937 * host and target. 938 */ 939 for (i = 0, committed = 0; i < cxlhdm->decoder_count; i++) { 940 ctrl = readl(hdm + CXL_HDM_DECODER0_CTRL_OFFSET(i)); 941 if (ctrl & CXL_HDM_DECODER0_CTRL_COMMITTED) 942 committed++; 943 } 944 945 /* ensure that future checks of committed can be trusted */ 946 if (committed != cxlhdm->decoder_count) 947 msleep(20); 948 } 949 950 /** 951 * devm_cxl_enumerate_decoders - add decoder objects per HDM register set 952 * @cxlhdm: Structure to populate with HDM capabilities 953 * @info: cached DVSEC range register info 954 */ 955 int devm_cxl_enumerate_decoders(struct cxl_hdm *cxlhdm, 956 struct cxl_endpoint_dvsec_info *info) 957 { 958 void __iomem *hdm = cxlhdm->regs.hdm_decoder; 959 struct cxl_port *port = cxlhdm->port; 960 int i; 961 u64 dpa_base = 0; 962 963 cxl_settle_decoders(cxlhdm); 964 965 for (i = 0; i < cxlhdm->decoder_count; i++) { 966 int target_map[CXL_DECODER_MAX_INTERLEAVE] = { 0 }; 967 int rc, target_count = cxlhdm->target_count; 968 struct cxl_decoder *cxld; 969 970 if (is_cxl_endpoint(port)) { 971 struct cxl_endpoint_decoder *cxled; 972 973 cxled = cxl_endpoint_decoder_alloc(port); 974 if (IS_ERR(cxled)) { 975 dev_warn(&port->dev, 976 "Failed to allocate decoder%d.%d\n", 977 port->id, i); 978 return PTR_ERR(cxled); 979 } 980 cxld = &cxled->cxld; 981 } else { 982 struct cxl_switch_decoder *cxlsd; 983 984 cxlsd = cxl_switch_decoder_alloc(port, target_count); 985 if (IS_ERR(cxlsd)) { 986 dev_warn(&port->dev, 987 "Failed to allocate decoder%d.%d\n", 988 port->id, i); 989 return PTR_ERR(cxlsd); 990 } 991 cxld = &cxlsd->cxld; 992 } 993 994 rc = init_hdm_decoder(port, cxld, target_map, hdm, i, 995 &dpa_base, info); 996 if (rc) { 997 dev_warn(&port->dev, 998 "Failed to initialize decoder%d.%d\n", 999 port->id, i); 1000 put_device(&cxld->dev); 1001 return rc; 1002 } 1003 rc = add_hdm_decoder(port, cxld, target_map); 1004 if (rc) { 1005 dev_warn(&port->dev, 1006 "Failed to add decoder%d.%d\n", port->id, i); 1007 return rc; 1008 } 1009 } 1010 1011 return 0; 1012 } 1013 EXPORT_SYMBOL_NS_GPL(devm_cxl_enumerate_decoders, CXL); 1014