1// SPDX-License-Identifier: GPL-2.0-only 2/* Copyright(c) 2020 Intel Corporation. */ 3#include <linux/io-64-nonatomic-lo-hi.h> 4#include <linux/device.h> 5#include <linux/slab.h> 6#include <linux/pci.h> 7#include <cxlmem.h> 8#include <cxlpci.h> 9#include <pmu.h> 10 11#include "core.h" 12 13/** 14 * DOC: cxl registers 15 * 16 * CXL device capabilities are enumerated by PCI DVSEC (Designated 17 * Vendor-specific) and / or descriptors provided by platform firmware. 18 * They can be defined as a set like the device and component registers 19 * mandated by CXL Section 8.1.12.2 Memory Device PCIe Capabilities and 20 * Extended Capabilities, or they can be individual capabilities 21 * appended to bridged and endpoint devices. 22 * 23 * Provide common infrastructure for enumerating and mapping these 24 * discrete capabilities. 25 */ 26 27/** 28 * cxl_probe_component_regs() - Detect CXL Component register blocks 29 * @dev: Host device of the @base mapping 30 * @base: Mapping containing the HDM Decoder Capability Header 31 * @map: Map object describing the register block information found 32 * 33 * See CXL 2.0 8.2.4 Component Register Layout and Definition 34 * See CXL 2.0 8.2.5.5 CXL Device Register Interface 35 * 36 * Probe for component register information and return it in map object. 37 */ 38void cxl_probe_component_regs(struct device *dev, void __iomem *base, 39 struct cxl_component_reg_map *map) 40{ 41 int cap, cap_count; 42 u32 cap_array; 43 44 *map = (struct cxl_component_reg_map) { 0 }; 45 46 /* 47 * CXL.cache and CXL.mem registers are at offset 0x1000 as defined in 48 * CXL 2.0 8.2.4 Table 141. 49 */ 50 base += CXL_CM_OFFSET; 51 52 cap_array = readl(base + CXL_CM_CAP_HDR_OFFSET); 53 54 if (FIELD_GET(CXL_CM_CAP_HDR_ID_MASK, cap_array) != CM_CAP_HDR_CAP_ID) { 55 dev_err(dev, 56 "Couldn't locate the CXL.cache and CXL.mem capability array header.\n"); 57 return; 58 } 59 60 /* It's assumed that future versions will be backward compatible */ 61 cap_count = FIELD_GET(CXL_CM_CAP_HDR_ARRAY_SIZE_MASK, cap_array); 62 63 for (cap = 1; cap <= cap_count; cap++) { 64 void __iomem *register_block; 65 struct cxl_reg_map *rmap; 66 u16 cap_id, offset; 67 u32 length, hdr; 68 69 hdr = readl(base + cap * 0x4); 70 71 cap_id = FIELD_GET(CXL_CM_CAP_HDR_ID_MASK, hdr); 72 offset = FIELD_GET(CXL_CM_CAP_PTR_MASK, hdr); 73 register_block = base + offset; 74 hdr = readl(register_block); 75 76 rmap = NULL; 77 switch (cap_id) { 78 case CXL_CM_CAP_CAP_ID_HDM: { 79 int decoder_cnt; 80 81 dev_dbg(dev, "found HDM decoder capability (0x%x)\n", 82 offset); 83 84 decoder_cnt = cxl_hdm_decoder_count(hdr); 85 length = 0x20 * decoder_cnt + 0x10; 86 rmap = &map->hdm_decoder; 87 break; 88 } 89 case CXL_CM_CAP_CAP_ID_RAS: 90 dev_dbg(dev, "found RAS capability (0x%x)\n", 91 offset); 92 length = CXL_RAS_CAPABILITY_LENGTH; 93 rmap = &map->ras; 94 break; 95 default: 96 dev_dbg(dev, "Unknown CM cap ID: %d (0x%x)\n", cap_id, 97 offset); 98 break; 99 } 100 101 if (!rmap) 102 continue; 103 rmap->valid = true; 104 rmap->id = cap_id; 105 rmap->offset = CXL_CM_OFFSET + offset; 106 rmap->size = length; 107 } 108} 109EXPORT_SYMBOL_NS_GPL(cxl_probe_component_regs, CXL); 110 111/** 112 * cxl_probe_device_regs() - Detect CXL Device register blocks 113 * @dev: Host device of the @base mapping 114 * @base: Mapping of CXL 2.0 8.2.8 CXL Device Register Interface 115 * @map: Map object describing the register block information found 116 * 117 * Probe for device register information and return it in map object. 118 */ 119void cxl_probe_device_regs(struct device *dev, void __iomem *base, 120 struct cxl_device_reg_map *map) 121{ 122 int cap, cap_count; 123 u64 cap_array; 124 125 *map = (struct cxl_device_reg_map){ 0 }; 126 127 cap_array = readq(base + CXLDEV_CAP_ARRAY_OFFSET); 128 if (FIELD_GET(CXLDEV_CAP_ARRAY_ID_MASK, cap_array) != 129 CXLDEV_CAP_ARRAY_CAP_ID) 130 return; 131 132 cap_count = FIELD_GET(CXLDEV_CAP_ARRAY_COUNT_MASK, cap_array); 133 134 for (cap = 1; cap <= cap_count; cap++) { 135 struct cxl_reg_map *rmap; 136 u32 offset, length; 137 u16 cap_id; 138 139 cap_id = FIELD_GET(CXLDEV_CAP_HDR_CAP_ID_MASK, 140 readl(base + cap * 0x10)); 141 offset = readl(base + cap * 0x10 + 0x4); 142 length = readl(base + cap * 0x10 + 0x8); 143 144 rmap = NULL; 145 switch (cap_id) { 146 case CXLDEV_CAP_CAP_ID_DEVICE_STATUS: 147 dev_dbg(dev, "found Status capability (0x%x)\n", offset); 148 rmap = &map->status; 149 break; 150 case CXLDEV_CAP_CAP_ID_PRIMARY_MAILBOX: 151 dev_dbg(dev, "found Mailbox capability (0x%x)\n", offset); 152 rmap = &map->mbox; 153 break; 154 case CXLDEV_CAP_CAP_ID_SECONDARY_MAILBOX: 155 dev_dbg(dev, "found Secondary Mailbox capability (0x%x)\n", offset); 156 break; 157 case CXLDEV_CAP_CAP_ID_MEMDEV: 158 dev_dbg(dev, "found Memory Device capability (0x%x)\n", offset); 159 rmap = &map->memdev; 160 break; 161 default: 162 if (cap_id >= 0x8000) 163 dev_dbg(dev, "Vendor cap ID: %#x offset: %#x\n", cap_id, offset); 164 else 165 dev_dbg(dev, "Unknown cap ID: %#x offset: %#x\n", cap_id, offset); 166 break; 167 } 168 169 if (!rmap) 170 continue; 171 rmap->valid = true; 172 rmap->id = cap_id; 173 rmap->offset = offset; 174 rmap->size = length; 175 } 176} 177EXPORT_SYMBOL_NS_GPL(cxl_probe_device_regs, CXL); 178 179void __iomem *devm_cxl_iomap_block(struct device *dev, resource_size_t addr, 180 resource_size_t length) 181{ 182 void __iomem *ret_val; 183 struct resource *res; 184 185 if (WARN_ON_ONCE(addr == CXL_RESOURCE_NONE)) 186 return NULL; 187 188 res = devm_request_mem_region(dev, addr, length, dev_name(dev)); 189 if (!res) { 190 resource_size_t end = addr + length - 1; 191 192 dev_err(dev, "Failed to request region %pa-%pa\n", &addr, &end); 193 return NULL; 194 } 195 196 ret_val = devm_ioremap(dev, addr, length); 197 if (!ret_val) 198 dev_err(dev, "Failed to map region %pr\n", res); 199 200 return ret_val; 201} 202 203int cxl_map_component_regs(const struct cxl_register_map *map, 204 struct cxl_component_regs *regs, 205 unsigned long map_mask) 206{ 207 struct device *host = map->host; 208 struct mapinfo { 209 const struct cxl_reg_map *rmap; 210 void __iomem **addr; 211 } mapinfo[] = { 212 { &map->component_map.hdm_decoder, ®s->hdm_decoder }, 213 { &map->component_map.ras, ®s->ras }, 214 }; 215 int i; 216 217 for (i = 0; i < ARRAY_SIZE(mapinfo); i++) { 218 struct mapinfo *mi = &mapinfo[i]; 219 resource_size_t addr; 220 resource_size_t length; 221 222 if (!mi->rmap->valid) 223 continue; 224 if (!test_bit(mi->rmap->id, &map_mask)) 225 continue; 226 addr = map->resource + mi->rmap->offset; 227 length = mi->rmap->size; 228 *(mi->addr) = devm_cxl_iomap_block(host, addr, length); 229 if (!*(mi->addr)) 230 return -ENOMEM; 231 } 232 233 return 0; 234} 235EXPORT_SYMBOL_NS_GPL(cxl_map_component_regs, CXL); 236 237int cxl_map_device_regs(const struct cxl_register_map *map, 238 struct cxl_device_regs *regs) 239{ 240 struct device *host = map->host; 241 resource_size_t phys_addr = map->resource; 242 struct mapinfo { 243 const struct cxl_reg_map *rmap; 244 void __iomem **addr; 245 } mapinfo[] = { 246 { &map->device_map.status, ®s->status, }, 247 { &map->device_map.mbox, ®s->mbox, }, 248 { &map->device_map.memdev, ®s->memdev, }, 249 }; 250 int i; 251 252 for (i = 0; i < ARRAY_SIZE(mapinfo); i++) { 253 struct mapinfo *mi = &mapinfo[i]; 254 resource_size_t length; 255 resource_size_t addr; 256 257 if (!mi->rmap->valid) 258 continue; 259 260 addr = phys_addr + mi->rmap->offset; 261 length = mi->rmap->size; 262 *(mi->addr) = devm_cxl_iomap_block(host, addr, length); 263 if (!*(mi->addr)) 264 return -ENOMEM; 265 } 266 267 return 0; 268} 269EXPORT_SYMBOL_NS_GPL(cxl_map_device_regs, CXL); 270 271static bool cxl_decode_regblock(struct pci_dev *pdev, u32 reg_lo, u32 reg_hi, 272 struct cxl_register_map *map) 273{ 274 u8 reg_type = FIELD_GET(CXL_DVSEC_REG_LOCATOR_BLOCK_ID_MASK, reg_lo); 275 int bar = FIELD_GET(CXL_DVSEC_REG_LOCATOR_BIR_MASK, reg_lo); 276 u64 offset = ((u64)reg_hi << 32) | 277 (reg_lo & CXL_DVSEC_REG_LOCATOR_BLOCK_OFF_LOW_MASK); 278 279 if (offset > pci_resource_len(pdev, bar)) { 280 dev_warn(&pdev->dev, 281 "BAR%d: %pr: too small (offset: %pa, type: %d)\n", bar, 282 &pdev->resource[bar], &offset, reg_type); 283 return false; 284 } 285 286 map->reg_type = reg_type; 287 map->resource = pci_resource_start(pdev, bar) + offset; 288 map->max_size = pci_resource_len(pdev, bar) - offset; 289 return true; 290} 291 292/** 293 * cxl_find_regblock_instance() - Locate a register block by type / index 294 * @pdev: The CXL PCI device to enumerate. 295 * @type: Register Block Indicator id 296 * @map: Enumeration output, clobbered on error 297 * @index: Index into which particular instance of a regblock wanted in the 298 * order found in register locator DVSEC. 299 * 300 * Return: 0 if register block enumerated, negative error code otherwise 301 * 302 * A CXL DVSEC may point to one or more register blocks, search for them 303 * by @type and @index. 304 */ 305int cxl_find_regblock_instance(struct pci_dev *pdev, enum cxl_regloc_type type, 306 struct cxl_register_map *map, int index) 307{ 308 u32 regloc_size, regblocks; 309 int instance = 0; 310 int regloc, i; 311 312 *map = (struct cxl_register_map) { 313 .host = &pdev->dev, 314 .resource = CXL_RESOURCE_NONE, 315 }; 316 317 regloc = pci_find_dvsec_capability(pdev, PCI_DVSEC_VENDOR_ID_CXL, 318 CXL_DVSEC_REG_LOCATOR); 319 if (!regloc) 320 return -ENXIO; 321 322 pci_read_config_dword(pdev, regloc + PCI_DVSEC_HEADER1, ®loc_size); 323 regloc_size = FIELD_GET(PCI_DVSEC_HEADER1_LENGTH_MASK, regloc_size); 324 325 regloc += CXL_DVSEC_REG_LOCATOR_BLOCK1_OFFSET; 326 regblocks = (regloc_size - CXL_DVSEC_REG_LOCATOR_BLOCK1_OFFSET) / 8; 327 328 for (i = 0; i < regblocks; i++, regloc += 8) { 329 u32 reg_lo, reg_hi; 330 331 pci_read_config_dword(pdev, regloc, ®_lo); 332 pci_read_config_dword(pdev, regloc + 4, ®_hi); 333 334 if (!cxl_decode_regblock(pdev, reg_lo, reg_hi, map)) 335 continue; 336 337 if (map->reg_type == type) { 338 if (index == instance) 339 return 0; 340 instance++; 341 } 342 } 343 344 map->resource = CXL_RESOURCE_NONE; 345 return -ENODEV; 346} 347EXPORT_SYMBOL_NS_GPL(cxl_find_regblock_instance, CXL); 348 349/** 350 * cxl_find_regblock() - Locate register blocks by type 351 * @pdev: The CXL PCI device to enumerate. 352 * @type: Register Block Indicator id 353 * @map: Enumeration output, clobbered on error 354 * 355 * Return: 0 if register block enumerated, negative error code otherwise 356 * 357 * A CXL DVSEC may point to one or more register blocks, search for them 358 * by @type. 359 */ 360int cxl_find_regblock(struct pci_dev *pdev, enum cxl_regloc_type type, 361 struct cxl_register_map *map) 362{ 363 return cxl_find_regblock_instance(pdev, type, map, 0); 364} 365EXPORT_SYMBOL_NS_GPL(cxl_find_regblock, CXL); 366 367/** 368 * cxl_count_regblock() - Count instances of a given regblock type. 369 * @pdev: The CXL PCI device to enumerate. 370 * @type: Register Block Indicator id 371 * 372 * Some regblocks may be repeated. Count how many instances. 373 * 374 * Return: count of matching regblocks. 375 */ 376int cxl_count_regblock(struct pci_dev *pdev, enum cxl_regloc_type type) 377{ 378 struct cxl_register_map map; 379 int rc, count = 0; 380 381 while (1) { 382 rc = cxl_find_regblock_instance(pdev, type, &map, count); 383 if (rc) 384 return count; 385 count++; 386 } 387} 388EXPORT_SYMBOL_NS_GPL(cxl_count_regblock, CXL); 389 390int cxl_map_pmu_regs(struct cxl_register_map *map, struct cxl_pmu_regs *regs) 391{ 392 struct device *dev = map->host; 393 resource_size_t phys_addr; 394 395 phys_addr = map->resource; 396 regs->pmu = devm_cxl_iomap_block(dev, phys_addr, CXL_PMU_REGMAP_SIZE); 397 if (!regs->pmu) 398 return -ENOMEM; 399 400 return 0; 401} 402EXPORT_SYMBOL_NS_GPL(cxl_map_pmu_regs, CXL); 403 404static int cxl_map_regblock(struct cxl_register_map *map) 405{ 406 struct device *host = map->host; 407 408 map->base = ioremap(map->resource, map->max_size); 409 if (!map->base) { 410 dev_err(host, "failed to map registers\n"); 411 return -ENOMEM; 412 } 413 414 dev_dbg(host, "Mapped CXL Memory Device resource %pa\n", &map->resource); 415 return 0; 416} 417 418static void cxl_unmap_regblock(struct cxl_register_map *map) 419{ 420 iounmap(map->base); 421 map->base = NULL; 422} 423 424static int cxl_probe_regs(struct cxl_register_map *map) 425{ 426 struct cxl_component_reg_map *comp_map; 427 struct cxl_device_reg_map *dev_map; 428 struct device *host = map->host; 429 void __iomem *base = map->base; 430 431 switch (map->reg_type) { 432 case CXL_REGLOC_RBI_COMPONENT: 433 comp_map = &map->component_map; 434 cxl_probe_component_regs(host, base, comp_map); 435 dev_dbg(host, "Set up component registers\n"); 436 break; 437 case CXL_REGLOC_RBI_MEMDEV: 438 dev_map = &map->device_map; 439 cxl_probe_device_regs(host, base, dev_map); 440 if (!dev_map->status.valid || !dev_map->mbox.valid || 441 !dev_map->memdev.valid) { 442 dev_err(host, "registers not found: %s%s%s\n", 443 !dev_map->status.valid ? "status " : "", 444 !dev_map->mbox.valid ? "mbox " : "", 445 !dev_map->memdev.valid ? "memdev " : ""); 446 return -ENXIO; 447 } 448 449 dev_dbg(host, "Probing device registers...\n"); 450 break; 451 default: 452 break; 453 } 454 455 return 0; 456} 457 458int cxl_setup_regs(struct cxl_register_map *map) 459{ 460 int rc; 461 462 rc = cxl_map_regblock(map); 463 if (rc) 464 return rc; 465 466 rc = cxl_probe_regs(map); 467 cxl_unmap_regblock(map); 468 469 return rc; 470} 471EXPORT_SYMBOL_NS_GPL(cxl_setup_regs, CXL); 472 473u16 cxl_rcrb_to_aer(struct device *dev, resource_size_t rcrb) 474{ 475 void __iomem *addr; 476 u16 offset = 0; 477 u32 cap_hdr; 478 479 if (WARN_ON_ONCE(rcrb == CXL_RESOURCE_NONE)) 480 return 0; 481 482 if (!request_mem_region(rcrb, SZ_4K, dev_name(dev))) 483 return 0; 484 485 addr = ioremap(rcrb, SZ_4K); 486 if (!addr) 487 goto out; 488 489 cap_hdr = readl(addr + offset); 490 while (PCI_EXT_CAP_ID(cap_hdr) != PCI_EXT_CAP_ID_ERR) { 491 offset = PCI_EXT_CAP_NEXT(cap_hdr); 492 493 /* Offset 0 terminates capability list. */ 494 if (!offset) 495 break; 496 cap_hdr = readl(addr + offset); 497 } 498 499 if (offset) 500 dev_dbg(dev, "found AER extended capability (0x%x)\n", offset); 501 502 iounmap(addr); 503out: 504 release_mem_region(rcrb, SZ_4K); 505 506 return offset; 507} 508 509resource_size_t __rcrb_to_component(struct device *dev, struct cxl_rcrb_info *ri, 510 enum cxl_rcrb which) 511{ 512 resource_size_t component_reg_phys; 513 resource_size_t rcrb = ri->base; 514 void __iomem *addr; 515 u32 bar0, bar1; 516 u16 cmd; 517 u32 id; 518 519 if (which == CXL_RCRB_UPSTREAM) 520 rcrb += SZ_4K; 521 522 /* 523 * RCRB's BAR[0..1] point to component block containing CXL 524 * subsystem component registers. MEMBAR extraction follows 525 * the PCI Base spec here, esp. 64 bit extraction and memory 526 * ranges alignment (6.0, 7.5.1.2.1). 527 */ 528 if (!request_mem_region(rcrb, SZ_4K, "CXL RCRB")) 529 return CXL_RESOURCE_NONE; 530 addr = ioremap(rcrb, SZ_4K); 531 if (!addr) { 532 dev_err(dev, "Failed to map region %pr\n", addr); 533 release_mem_region(rcrb, SZ_4K); 534 return CXL_RESOURCE_NONE; 535 } 536 537 id = readl(addr + PCI_VENDOR_ID); 538 cmd = readw(addr + PCI_COMMAND); 539 bar0 = readl(addr + PCI_BASE_ADDRESS_0); 540 bar1 = readl(addr + PCI_BASE_ADDRESS_1); 541 iounmap(addr); 542 release_mem_region(rcrb, SZ_4K); 543 544 /* 545 * Sanity check, see CXL 3.0 Figure 9-8 CXL Device that Does Not 546 * Remap Upstream Port and Component Registers 547 */ 548 if (id == U32_MAX) { 549 if (which == CXL_RCRB_DOWNSTREAM) 550 dev_err(dev, "Failed to access Downstream Port RCRB\n"); 551 return CXL_RESOURCE_NONE; 552 } 553 if (!(cmd & PCI_COMMAND_MEMORY)) 554 return CXL_RESOURCE_NONE; 555 /* The RCRB is a Memory Window, and the MEM_TYPE_1M bit is obsolete */ 556 if (bar0 & (PCI_BASE_ADDRESS_MEM_TYPE_1M | PCI_BASE_ADDRESS_SPACE_IO)) 557 return CXL_RESOURCE_NONE; 558 559 component_reg_phys = bar0 & PCI_BASE_ADDRESS_MEM_MASK; 560 if (bar0 & PCI_BASE_ADDRESS_MEM_TYPE_64) 561 component_reg_phys |= ((u64)bar1) << 32; 562 563 if (!component_reg_phys) 564 return CXL_RESOURCE_NONE; 565 566 /* MEMBAR is block size (64k) aligned. */ 567 if (!IS_ALIGNED(component_reg_phys, CXL_COMPONENT_REG_BLOCK_SIZE)) 568 return CXL_RESOURCE_NONE; 569 570 return component_reg_phys; 571} 572 573resource_size_t cxl_rcd_component_reg_phys(struct device *dev, 574 struct cxl_dport *dport) 575{ 576 if (!dport->rch) 577 return CXL_RESOURCE_NONE; 578 return __rcrb_to_component(dev, &dport->rcrb, CXL_RCRB_UPSTREAM); 579} 580EXPORT_SYMBOL_NS_GPL(cxl_rcd_component_reg_phys, CXL); 581