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 phys_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 phys_addr = map->resource + mi->rmap->offset; 227 length = mi->rmap->size; 228 *(mi->addr) = devm_cxl_iomap_block(host, phys_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 int bar = FIELD_GET(CXL_DVSEC_REG_LOCATOR_BIR_MASK, reg_lo); 275 u64 offset = ((u64)reg_hi << 32) | 276 (reg_lo & CXL_DVSEC_REG_LOCATOR_BLOCK_OFF_LOW_MASK); 277 278 if (offset > pci_resource_len(pdev, bar)) { 279 dev_warn(&pdev->dev, 280 "BAR%d: %pr: too small (offset: %pa, type: %d)\n", bar, 281 &pdev->resource[bar], &offset, map->reg_type); 282 return false; 283 } 284 285 map->reg_type = FIELD_GET(CXL_DVSEC_REG_LOCATOR_BLOCK_ID_MASK, reg_lo); 286 map->resource = pci_resource_start(pdev, bar) + offset; 287 map->max_size = pci_resource_len(pdev, bar) - offset; 288 return true; 289} 290 291/** 292 * cxl_find_regblock_instance() - Locate a register block by type / index 293 * @pdev: The CXL PCI device to enumerate. 294 * @type: Register Block Indicator id 295 * @map: Enumeration output, clobbered on error 296 * @index: Index into which particular instance of a regblock wanted in the 297 * order found in register locator DVSEC. 298 * 299 * Return: 0 if register block enumerated, negative error code otherwise 300 * 301 * A CXL DVSEC may point to one or more register blocks, search for them 302 * by @type and @index. 303 */ 304int cxl_find_regblock_instance(struct pci_dev *pdev, enum cxl_regloc_type type, 305 struct cxl_register_map *map, int index) 306{ 307 u32 regloc_size, regblocks; 308 int instance = 0; 309 int regloc, i; 310 311 *map = (struct cxl_register_map) { 312 .host = &pdev->dev, 313 .resource = CXL_RESOURCE_NONE, 314 }; 315 316 regloc = pci_find_dvsec_capability(pdev, PCI_DVSEC_VENDOR_ID_CXL, 317 CXL_DVSEC_REG_LOCATOR); 318 if (!regloc) 319 return -ENXIO; 320 321 pci_read_config_dword(pdev, regloc + PCI_DVSEC_HEADER1, ®loc_size); 322 regloc_size = FIELD_GET(PCI_DVSEC_HEADER1_LENGTH_MASK, regloc_size); 323 324 regloc += CXL_DVSEC_REG_LOCATOR_BLOCK1_OFFSET; 325 regblocks = (regloc_size - CXL_DVSEC_REG_LOCATOR_BLOCK1_OFFSET) / 8; 326 327 for (i = 0; i < regblocks; i++, regloc += 8) { 328 u32 reg_lo, reg_hi; 329 330 pci_read_config_dword(pdev, regloc, ®_lo); 331 pci_read_config_dword(pdev, regloc + 4, ®_hi); 332 333 if (!cxl_decode_regblock(pdev, reg_lo, reg_hi, map)) 334 continue; 335 336 if (map->reg_type == type) { 337 if (index == instance) 338 return 0; 339 instance++; 340 } 341 } 342 343 map->resource = CXL_RESOURCE_NONE; 344 return -ENODEV; 345} 346EXPORT_SYMBOL_NS_GPL(cxl_find_regblock_instance, CXL); 347 348/** 349 * cxl_find_regblock() - Locate register blocks by type 350 * @pdev: The CXL PCI device to enumerate. 351 * @type: Register Block Indicator id 352 * @map: Enumeration output, clobbered on error 353 * 354 * Return: 0 if register block enumerated, negative error code otherwise 355 * 356 * A CXL DVSEC may point to one or more register blocks, search for them 357 * by @type. 358 */ 359int cxl_find_regblock(struct pci_dev *pdev, enum cxl_regloc_type type, 360 struct cxl_register_map *map) 361{ 362 return cxl_find_regblock_instance(pdev, type, map, 0); 363} 364EXPORT_SYMBOL_NS_GPL(cxl_find_regblock, CXL); 365 366/** 367 * cxl_count_regblock() - Count instances of a given regblock type. 368 * @pdev: The CXL PCI device to enumerate. 369 * @type: Register Block Indicator id 370 * 371 * Some regblocks may be repeated. Count how many instances. 372 * 373 * Return: count of matching regblocks. 374 */ 375int cxl_count_regblock(struct pci_dev *pdev, enum cxl_regloc_type type) 376{ 377 struct cxl_register_map map; 378 int rc, count = 0; 379 380 while (1) { 381 rc = cxl_find_regblock_instance(pdev, type, &map, count); 382 if (rc) 383 return count; 384 count++; 385 } 386} 387EXPORT_SYMBOL_NS_GPL(cxl_count_regblock, CXL); 388 389int cxl_map_pmu_regs(struct pci_dev *pdev, struct cxl_pmu_regs *regs, 390 struct cxl_register_map *map) 391{ 392 struct device *dev = &pdev->dev; 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 473resource_size_t __rcrb_to_component(struct device *dev, struct cxl_rcrb_info *ri, 474 enum cxl_rcrb which) 475{ 476 resource_size_t component_reg_phys; 477 resource_size_t rcrb = ri->base; 478 void __iomem *addr; 479 u32 bar0, bar1; 480 u16 cmd; 481 u32 id; 482 483 if (which == CXL_RCRB_UPSTREAM) 484 rcrb += SZ_4K; 485 486 /* 487 * RCRB's BAR[0..1] point to component block containing CXL 488 * subsystem component registers. MEMBAR extraction follows 489 * the PCI Base spec here, esp. 64 bit extraction and memory 490 * ranges alignment (6.0, 7.5.1.2.1). 491 */ 492 if (!request_mem_region(rcrb, SZ_4K, "CXL RCRB")) 493 return CXL_RESOURCE_NONE; 494 addr = ioremap(rcrb, SZ_4K); 495 if (!addr) { 496 dev_err(dev, "Failed to map region %pr\n", addr); 497 release_mem_region(rcrb, SZ_4K); 498 return CXL_RESOURCE_NONE; 499 } 500 501 id = readl(addr + PCI_VENDOR_ID); 502 cmd = readw(addr + PCI_COMMAND); 503 bar0 = readl(addr + PCI_BASE_ADDRESS_0); 504 bar1 = readl(addr + PCI_BASE_ADDRESS_1); 505 iounmap(addr); 506 release_mem_region(rcrb, SZ_4K); 507 508 /* 509 * Sanity check, see CXL 3.0 Figure 9-8 CXL Device that Does Not 510 * Remap Upstream Port and Component Registers 511 */ 512 if (id == U32_MAX) { 513 if (which == CXL_RCRB_DOWNSTREAM) 514 dev_err(dev, "Failed to access Downstream Port RCRB\n"); 515 return CXL_RESOURCE_NONE; 516 } 517 if (!(cmd & PCI_COMMAND_MEMORY)) 518 return CXL_RESOURCE_NONE; 519 /* The RCRB is a Memory Window, and the MEM_TYPE_1M bit is obsolete */ 520 if (bar0 & (PCI_BASE_ADDRESS_MEM_TYPE_1M | PCI_BASE_ADDRESS_SPACE_IO)) 521 return CXL_RESOURCE_NONE; 522 523 component_reg_phys = bar0 & PCI_BASE_ADDRESS_MEM_MASK; 524 if (bar0 & PCI_BASE_ADDRESS_MEM_TYPE_64) 525 component_reg_phys |= ((u64)bar1) << 32; 526 527 if (!component_reg_phys) 528 return CXL_RESOURCE_NONE; 529 530 /* MEMBAR is block size (64k) aligned. */ 531 if (!IS_ALIGNED(component_reg_phys, CXL_COMPONENT_REG_BLOCK_SIZE)) 532 return CXL_RESOURCE_NONE; 533 534 return component_reg_phys; 535} 536 537resource_size_t cxl_rcd_component_reg_phys(struct device *dev, 538 struct cxl_dport *dport) 539{ 540 if (!dport->rch) 541 return CXL_RESOURCE_NONE; 542 return __rcrb_to_component(dev, &dport->rcrb, CXL_RCRB_UPSTREAM); 543} 544EXPORT_SYMBOL_NS_GPL(cxl_rcd_component_reg_phys, CXL); 545