1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * PCI Express PCI Hot Plug Driver 4 * 5 * Copyright (C) 1995,2001 Compaq Computer Corporation 6 * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com) 7 * Copyright (C) 2001 IBM Corp. 8 * Copyright (C) 2003-2004 Intel Corporation 9 * 10 * All rights reserved. 11 * 12 * Send feedback to <greg@kroah.com>,<kristen.c.accardi@intel.com> 13 */ 14 15 #define dev_fmt(fmt) "pciehp: " fmt 16 17 #include <linux/dmi.h> 18 #include <linux/kernel.h> 19 #include <linux/types.h> 20 #include <linux/jiffies.h> 21 #include <linux/kthread.h> 22 #include <linux/pci.h> 23 #include <linux/pm_runtime.h> 24 #include <linux/interrupt.h> 25 #include <linux/slab.h> 26 27 #include "../pci.h" 28 #include "pciehp.h" 29 30 static const struct dmi_system_id inband_presence_disabled_dmi_table[] = { 31 /* 32 * Match all Dell systems, as some Dell systems have inband 33 * presence disabled on NVMe slots (but don't support the bit to 34 * report it). Setting inband presence disabled should have no 35 * negative effect, except on broken hotplug slots that never 36 * assert presence detect--and those will still work, they will 37 * just have a bit of extra delay before being probed. 38 */ 39 { 40 .ident = "Dell System", 41 .matches = { 42 DMI_MATCH(DMI_OEM_STRING, "Dell System"), 43 }, 44 }, 45 {} 46 }; 47 48 static inline struct pci_dev *ctrl_dev(struct controller *ctrl) 49 { 50 return ctrl->pcie->port; 51 } 52 53 static irqreturn_t pciehp_isr(int irq, void *dev_id); 54 static irqreturn_t pciehp_ist(int irq, void *dev_id); 55 static int pciehp_poll(void *data); 56 57 static inline int pciehp_request_irq(struct controller *ctrl) 58 { 59 int retval, irq = ctrl->pcie->irq; 60 61 if (pciehp_poll_mode) { 62 ctrl->poll_thread = kthread_run(&pciehp_poll, ctrl, 63 "pciehp_poll-%s", 64 slot_name(ctrl)); 65 return PTR_ERR_OR_ZERO(ctrl->poll_thread); 66 } 67 68 /* Installs the interrupt handler */ 69 retval = request_threaded_irq(irq, pciehp_isr, pciehp_ist, 70 IRQF_SHARED, "pciehp", ctrl); 71 if (retval) 72 ctrl_err(ctrl, "Cannot get irq %d for the hotplug controller\n", 73 irq); 74 return retval; 75 } 76 77 static inline void pciehp_free_irq(struct controller *ctrl) 78 { 79 if (pciehp_poll_mode) 80 kthread_stop(ctrl->poll_thread); 81 else 82 free_irq(ctrl->pcie->irq, ctrl); 83 } 84 85 static int pcie_poll_cmd(struct controller *ctrl, int timeout) 86 { 87 struct pci_dev *pdev = ctrl_dev(ctrl); 88 u16 slot_status; 89 90 do { 91 pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status); 92 if (PCI_POSSIBLE_ERROR(slot_status)) { 93 ctrl_info(ctrl, "%s: no response from device\n", 94 __func__); 95 return 0; 96 } 97 98 if (slot_status & PCI_EXP_SLTSTA_CC) { 99 pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, 100 PCI_EXP_SLTSTA_CC); 101 ctrl->cmd_busy = 0; 102 smp_mb(); 103 return 1; 104 } 105 msleep(10); 106 timeout -= 10; 107 } while (timeout >= 0); 108 return 0; /* timeout */ 109 } 110 111 static void pcie_wait_cmd(struct controller *ctrl) 112 { 113 unsigned int msecs = pciehp_poll_mode ? 2500 : 1000; 114 unsigned long duration = msecs_to_jiffies(msecs); 115 unsigned long cmd_timeout = ctrl->cmd_started + duration; 116 unsigned long now, timeout; 117 int rc; 118 119 /* 120 * If the controller does not generate notifications for command 121 * completions, we never need to wait between writes. 122 */ 123 if (NO_CMD_CMPL(ctrl)) 124 return; 125 126 if (!ctrl->cmd_busy) 127 return; 128 129 /* 130 * Even if the command has already timed out, we want to call 131 * pcie_poll_cmd() so it can clear PCI_EXP_SLTSTA_CC. 132 */ 133 now = jiffies; 134 if (time_before_eq(cmd_timeout, now)) 135 timeout = 1; 136 else 137 timeout = cmd_timeout - now; 138 139 if (ctrl->slot_ctrl & PCI_EXP_SLTCTL_HPIE && 140 ctrl->slot_ctrl & PCI_EXP_SLTCTL_CCIE) 141 rc = wait_event_timeout(ctrl->queue, !ctrl->cmd_busy, timeout); 142 else 143 rc = pcie_poll_cmd(ctrl, jiffies_to_msecs(timeout)); 144 145 if (!rc) 146 ctrl_info(ctrl, "Timeout on hotplug command %#06x (issued %u msec ago)\n", 147 ctrl->slot_ctrl, 148 jiffies_to_msecs(jiffies - ctrl->cmd_started)); 149 } 150 151 #define CC_ERRATUM_MASK (PCI_EXP_SLTCTL_PCC | \ 152 PCI_EXP_SLTCTL_PIC | \ 153 PCI_EXP_SLTCTL_AIC | \ 154 PCI_EXP_SLTCTL_EIC) 155 156 static void pcie_do_write_cmd(struct controller *ctrl, u16 cmd, 157 u16 mask, bool wait) 158 { 159 struct pci_dev *pdev = ctrl_dev(ctrl); 160 u16 slot_ctrl_orig, slot_ctrl; 161 162 mutex_lock(&ctrl->ctrl_lock); 163 164 /* 165 * Always wait for any previous command that might still be in progress 166 */ 167 pcie_wait_cmd(ctrl); 168 169 pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &slot_ctrl); 170 if (PCI_POSSIBLE_ERROR(slot_ctrl)) { 171 ctrl_info(ctrl, "%s: no response from device\n", __func__); 172 goto out; 173 } 174 175 slot_ctrl_orig = slot_ctrl; 176 slot_ctrl &= ~mask; 177 slot_ctrl |= (cmd & mask); 178 ctrl->cmd_busy = 1; 179 smp_mb(); 180 ctrl->slot_ctrl = slot_ctrl; 181 pcie_capability_write_word(pdev, PCI_EXP_SLTCTL, slot_ctrl); 182 ctrl->cmd_started = jiffies; 183 184 /* 185 * Controllers with the Intel CF118 and similar errata advertise 186 * Command Completed support, but they only set Command Completed 187 * if we change the "Control" bits for power, power indicator, 188 * attention indicator, or interlock. If we only change the 189 * "Enable" bits, they never set the Command Completed bit. 190 */ 191 if (pdev->broken_cmd_compl && 192 (slot_ctrl_orig & CC_ERRATUM_MASK) == (slot_ctrl & CC_ERRATUM_MASK)) 193 ctrl->cmd_busy = 0; 194 195 /* 196 * Optionally wait for the hardware to be ready for a new command, 197 * indicating completion of the above issued command. 198 */ 199 if (wait) 200 pcie_wait_cmd(ctrl); 201 202 out: 203 mutex_unlock(&ctrl->ctrl_lock); 204 } 205 206 /** 207 * pcie_write_cmd - Issue controller command 208 * @ctrl: controller to which the command is issued 209 * @cmd: command value written to slot control register 210 * @mask: bitmask of slot control register to be modified 211 */ 212 static void pcie_write_cmd(struct controller *ctrl, u16 cmd, u16 mask) 213 { 214 pcie_do_write_cmd(ctrl, cmd, mask, true); 215 } 216 217 /* Same as above without waiting for the hardware to latch */ 218 static void pcie_write_cmd_nowait(struct controller *ctrl, u16 cmd, u16 mask) 219 { 220 pcie_do_write_cmd(ctrl, cmd, mask, false); 221 } 222 223 /** 224 * pciehp_check_link_active() - Is the link active 225 * @ctrl: PCIe hotplug controller 226 * 227 * Check whether the downstream link is currently active. Note it is 228 * possible that the card is removed immediately after this so the 229 * caller may need to take it into account. 230 * 231 * If the hotplug controller itself is not available anymore returns 232 * %-ENODEV. 233 */ 234 int pciehp_check_link_active(struct controller *ctrl) 235 { 236 struct pci_dev *pdev = ctrl_dev(ctrl); 237 u16 lnk_status; 238 int ret; 239 240 ret = pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status); 241 if (ret == PCIBIOS_DEVICE_NOT_FOUND || PCI_POSSIBLE_ERROR(lnk_status)) 242 return -ENODEV; 243 244 ret = !!(lnk_status & PCI_EXP_LNKSTA_DLLLA); 245 ctrl_dbg(ctrl, "%s: lnk_status = %x\n", __func__, lnk_status); 246 247 return ret; 248 } 249 250 static bool pci_bus_check_dev(struct pci_bus *bus, int devfn) 251 { 252 u32 l; 253 int count = 0; 254 int delay = 1000, step = 20; 255 bool found = false; 256 257 do { 258 found = pci_bus_read_dev_vendor_id(bus, devfn, &l, 0); 259 count++; 260 261 if (found) 262 break; 263 264 msleep(step); 265 delay -= step; 266 } while (delay > 0); 267 268 if (count > 1) 269 pr_debug("pci %04x:%02x:%02x.%d id reading try %d times with interval %d ms to get %08x\n", 270 pci_domain_nr(bus), bus->number, PCI_SLOT(devfn), 271 PCI_FUNC(devfn), count, step, l); 272 273 return found; 274 } 275 276 static void pcie_wait_for_presence(struct pci_dev *pdev) 277 { 278 int timeout = 1250; 279 u16 slot_status; 280 281 do { 282 pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status); 283 if (slot_status & PCI_EXP_SLTSTA_PDS) 284 return; 285 msleep(10); 286 timeout -= 10; 287 } while (timeout > 0); 288 } 289 290 int pciehp_check_link_status(struct controller *ctrl) 291 { 292 struct pci_dev *pdev = ctrl_dev(ctrl); 293 bool found; 294 u16 lnk_status; 295 296 if (!pcie_wait_for_link(pdev, true)) { 297 ctrl_info(ctrl, "Slot(%s): No link\n", slot_name(ctrl)); 298 return -1; 299 } 300 301 if (ctrl->inband_presence_disabled) 302 pcie_wait_for_presence(pdev); 303 304 found = pci_bus_check_dev(ctrl->pcie->port->subordinate, 305 PCI_DEVFN(0, 0)); 306 307 /* ignore link or presence changes up to this point */ 308 if (found) 309 atomic_and(~(PCI_EXP_SLTSTA_DLLSC | PCI_EXP_SLTSTA_PDC), 310 &ctrl->pending_events); 311 312 pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status); 313 ctrl_dbg(ctrl, "%s: lnk_status = %x\n", __func__, lnk_status); 314 if ((lnk_status & PCI_EXP_LNKSTA_LT) || 315 !(lnk_status & PCI_EXP_LNKSTA_NLW)) { 316 ctrl_info(ctrl, "Slot(%s): Cannot train link: status %#06x\n", 317 slot_name(ctrl), lnk_status); 318 return -1; 319 } 320 321 pcie_update_link_speed(ctrl->pcie->port->subordinate, lnk_status); 322 323 if (!found) { 324 ctrl_info(ctrl, "Slot(%s): No device found\n", 325 slot_name(ctrl)); 326 return -1; 327 } 328 329 return 0; 330 } 331 332 static int __pciehp_link_set(struct controller *ctrl, bool enable) 333 { 334 struct pci_dev *pdev = ctrl_dev(ctrl); 335 u16 lnk_ctrl; 336 337 pcie_capability_read_word(pdev, PCI_EXP_LNKCTL, &lnk_ctrl); 338 339 if (enable) 340 lnk_ctrl &= ~PCI_EXP_LNKCTL_LD; 341 else 342 lnk_ctrl |= PCI_EXP_LNKCTL_LD; 343 344 pcie_capability_write_word(pdev, PCI_EXP_LNKCTL, lnk_ctrl); 345 ctrl_dbg(ctrl, "%s: lnk_ctrl = %x\n", __func__, lnk_ctrl); 346 return 0; 347 } 348 349 static int pciehp_link_enable(struct controller *ctrl) 350 { 351 return __pciehp_link_set(ctrl, true); 352 } 353 354 int pciehp_get_raw_indicator_status(struct hotplug_slot *hotplug_slot, 355 u8 *status) 356 { 357 struct controller *ctrl = to_ctrl(hotplug_slot); 358 struct pci_dev *pdev = ctrl_dev(ctrl); 359 u16 slot_ctrl; 360 361 pci_config_pm_runtime_get(pdev); 362 pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &slot_ctrl); 363 pci_config_pm_runtime_put(pdev); 364 *status = (slot_ctrl & (PCI_EXP_SLTCTL_AIC | PCI_EXP_SLTCTL_PIC)) >> 6; 365 return 0; 366 } 367 368 int pciehp_get_attention_status(struct hotplug_slot *hotplug_slot, u8 *status) 369 { 370 struct controller *ctrl = to_ctrl(hotplug_slot); 371 struct pci_dev *pdev = ctrl_dev(ctrl); 372 u16 slot_ctrl; 373 374 pci_config_pm_runtime_get(pdev); 375 pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &slot_ctrl); 376 pci_config_pm_runtime_put(pdev); 377 ctrl_dbg(ctrl, "%s: SLOTCTRL %x, value read %x\n", __func__, 378 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_ctrl); 379 380 switch (slot_ctrl & PCI_EXP_SLTCTL_AIC) { 381 case PCI_EXP_SLTCTL_ATTN_IND_ON: 382 *status = 1; /* On */ 383 break; 384 case PCI_EXP_SLTCTL_ATTN_IND_BLINK: 385 *status = 2; /* Blink */ 386 break; 387 case PCI_EXP_SLTCTL_ATTN_IND_OFF: 388 *status = 0; /* Off */ 389 break; 390 default: 391 *status = 0xFF; 392 break; 393 } 394 395 return 0; 396 } 397 398 void pciehp_get_power_status(struct controller *ctrl, u8 *status) 399 { 400 struct pci_dev *pdev = ctrl_dev(ctrl); 401 u16 slot_ctrl; 402 403 pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &slot_ctrl); 404 ctrl_dbg(ctrl, "%s: SLOTCTRL %x value read %x\n", __func__, 405 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_ctrl); 406 407 switch (slot_ctrl & PCI_EXP_SLTCTL_PCC) { 408 case PCI_EXP_SLTCTL_PWR_ON: 409 *status = 1; /* On */ 410 break; 411 case PCI_EXP_SLTCTL_PWR_OFF: 412 *status = 0; /* Off */ 413 break; 414 default: 415 *status = 0xFF; 416 break; 417 } 418 } 419 420 void pciehp_get_latch_status(struct controller *ctrl, u8 *status) 421 { 422 struct pci_dev *pdev = ctrl_dev(ctrl); 423 u16 slot_status; 424 425 pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status); 426 *status = !!(slot_status & PCI_EXP_SLTSTA_MRLSS); 427 } 428 429 /** 430 * pciehp_card_present() - Is the card present 431 * @ctrl: PCIe hotplug controller 432 * 433 * Function checks whether the card is currently present in the slot and 434 * in that case returns true. Note it is possible that the card is 435 * removed immediately after the check so the caller may need to take 436 * this into account. 437 * 438 * It the hotplug controller itself is not available anymore returns 439 * %-ENODEV. 440 */ 441 int pciehp_card_present(struct controller *ctrl) 442 { 443 struct pci_dev *pdev = ctrl_dev(ctrl); 444 u16 slot_status; 445 int ret; 446 447 ret = pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status); 448 if (ret == PCIBIOS_DEVICE_NOT_FOUND || PCI_POSSIBLE_ERROR(slot_status)) 449 return -ENODEV; 450 451 return !!(slot_status & PCI_EXP_SLTSTA_PDS); 452 } 453 454 /** 455 * pciehp_card_present_or_link_active() - whether given slot is occupied 456 * @ctrl: PCIe hotplug controller 457 * 458 * Unlike pciehp_card_present(), which determines presence solely from the 459 * Presence Detect State bit, this helper also returns true if the Link Active 460 * bit is set. This is a concession to broken hotplug ports which hardwire 461 * Presence Detect State to zero, such as Wilocity's [1ae9:0200]. 462 * 463 * Returns: %1 if the slot is occupied and %0 if it is not. If the hotplug 464 * port is not present anymore returns %-ENODEV. 465 */ 466 int pciehp_card_present_or_link_active(struct controller *ctrl) 467 { 468 int ret; 469 470 ret = pciehp_card_present(ctrl); 471 if (ret) 472 return ret; 473 474 return pciehp_check_link_active(ctrl); 475 } 476 477 int pciehp_query_power_fault(struct controller *ctrl) 478 { 479 struct pci_dev *pdev = ctrl_dev(ctrl); 480 u16 slot_status; 481 482 pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status); 483 return !!(slot_status & PCI_EXP_SLTSTA_PFD); 484 } 485 486 int pciehp_set_raw_indicator_status(struct hotplug_slot *hotplug_slot, 487 u8 status) 488 { 489 struct controller *ctrl = to_ctrl(hotplug_slot); 490 struct pci_dev *pdev = ctrl_dev(ctrl); 491 492 pci_config_pm_runtime_get(pdev); 493 pcie_write_cmd_nowait(ctrl, status << 6, 494 PCI_EXP_SLTCTL_AIC | PCI_EXP_SLTCTL_PIC); 495 pci_config_pm_runtime_put(pdev); 496 return 0; 497 } 498 499 /** 500 * pciehp_set_indicators() - set attention indicator, power indicator, or both 501 * @ctrl: PCIe hotplug controller 502 * @pwr: one of: 503 * PCI_EXP_SLTCTL_PWR_IND_ON 504 * PCI_EXP_SLTCTL_PWR_IND_BLINK 505 * PCI_EXP_SLTCTL_PWR_IND_OFF 506 * @attn: one of: 507 * PCI_EXP_SLTCTL_ATTN_IND_ON 508 * PCI_EXP_SLTCTL_ATTN_IND_BLINK 509 * PCI_EXP_SLTCTL_ATTN_IND_OFF 510 * 511 * Either @pwr or @attn can also be INDICATOR_NOOP to leave that indicator 512 * unchanged. 513 */ 514 void pciehp_set_indicators(struct controller *ctrl, int pwr, int attn) 515 { 516 u16 cmd = 0, mask = 0; 517 518 if (PWR_LED(ctrl) && pwr != INDICATOR_NOOP) { 519 cmd |= (pwr & PCI_EXP_SLTCTL_PIC); 520 mask |= PCI_EXP_SLTCTL_PIC; 521 } 522 523 if (ATTN_LED(ctrl) && attn != INDICATOR_NOOP) { 524 cmd |= (attn & PCI_EXP_SLTCTL_AIC); 525 mask |= PCI_EXP_SLTCTL_AIC; 526 } 527 528 if (cmd) { 529 pcie_write_cmd_nowait(ctrl, cmd, mask); 530 ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__, 531 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, cmd); 532 } 533 } 534 535 int pciehp_power_on_slot(struct controller *ctrl) 536 { 537 struct pci_dev *pdev = ctrl_dev(ctrl); 538 u16 slot_status; 539 int retval; 540 541 /* Clear power-fault bit from previous power failures */ 542 pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status); 543 if (slot_status & PCI_EXP_SLTSTA_PFD) 544 pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, 545 PCI_EXP_SLTSTA_PFD); 546 ctrl->power_fault_detected = 0; 547 548 pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_PWR_ON, PCI_EXP_SLTCTL_PCC); 549 ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__, 550 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, 551 PCI_EXP_SLTCTL_PWR_ON); 552 553 retval = pciehp_link_enable(ctrl); 554 if (retval) 555 ctrl_err(ctrl, "%s: Can not enable the link!\n", __func__); 556 557 return retval; 558 } 559 560 void pciehp_power_off_slot(struct controller *ctrl) 561 { 562 pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_PWR_OFF, PCI_EXP_SLTCTL_PCC); 563 ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__, 564 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, 565 PCI_EXP_SLTCTL_PWR_OFF); 566 } 567 568 static void pciehp_ignore_dpc_link_change(struct controller *ctrl, 569 struct pci_dev *pdev, int irq) 570 { 571 /* 572 * Ignore link changes which occurred while waiting for DPC recovery. 573 * Could be several if DPC triggered multiple times consecutively. 574 */ 575 synchronize_hardirq(irq); 576 atomic_and(~PCI_EXP_SLTSTA_DLLSC, &ctrl->pending_events); 577 if (pciehp_poll_mode) 578 pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, 579 PCI_EXP_SLTSTA_DLLSC); 580 ctrl_info(ctrl, "Slot(%s): Link Down/Up ignored (recovered by DPC)\n", 581 slot_name(ctrl)); 582 583 /* 584 * If the link is unexpectedly down after successful recovery, 585 * the corresponding link change may have been ignored above. 586 * Synthesize it to ensure that it is acted on. 587 */ 588 down_read_nested(&ctrl->reset_lock, ctrl->depth); 589 if (!pciehp_check_link_active(ctrl)) 590 pciehp_request(ctrl, PCI_EXP_SLTSTA_DLLSC); 591 up_read(&ctrl->reset_lock); 592 } 593 594 static irqreturn_t pciehp_isr(int irq, void *dev_id) 595 { 596 struct controller *ctrl = (struct controller *)dev_id; 597 struct pci_dev *pdev = ctrl_dev(ctrl); 598 struct device *parent = pdev->dev.parent; 599 u16 status, events = 0; 600 601 /* 602 * Interrupts only occur in D3hot or shallower and only if enabled 603 * in the Slot Control register (PCIe r4.0, sec 6.7.3.4). 604 */ 605 if (pdev->current_state == PCI_D3cold || 606 (!(ctrl->slot_ctrl & PCI_EXP_SLTCTL_HPIE) && !pciehp_poll_mode)) 607 return IRQ_NONE; 608 609 /* 610 * Keep the port accessible by holding a runtime PM ref on its parent. 611 * Defer resume of the parent to the IRQ thread if it's suspended. 612 * Mask the interrupt until then. 613 */ 614 if (parent) { 615 pm_runtime_get_noresume(parent); 616 if (!pm_runtime_active(parent)) { 617 pm_runtime_put(parent); 618 disable_irq_nosync(irq); 619 atomic_or(RERUN_ISR, &ctrl->pending_events); 620 return IRQ_WAKE_THREAD; 621 } 622 } 623 624 read_status: 625 pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &status); 626 if (PCI_POSSIBLE_ERROR(status)) { 627 ctrl_info(ctrl, "%s: no response from device\n", __func__); 628 if (parent) 629 pm_runtime_put(parent); 630 return IRQ_NONE; 631 } 632 633 /* 634 * Slot Status contains plain status bits as well as event 635 * notification bits; right now we only want the event bits. 636 */ 637 status &= PCI_EXP_SLTSTA_ABP | PCI_EXP_SLTSTA_PFD | 638 PCI_EXP_SLTSTA_PDC | PCI_EXP_SLTSTA_CC | 639 PCI_EXP_SLTSTA_DLLSC; 640 641 /* 642 * If we've already reported a power fault, don't report it again 643 * until we've done something to handle it. 644 */ 645 if (ctrl->power_fault_detected) 646 status &= ~PCI_EXP_SLTSTA_PFD; 647 else if (status & PCI_EXP_SLTSTA_PFD) 648 ctrl->power_fault_detected = true; 649 650 events |= status; 651 if (!events) { 652 if (parent) 653 pm_runtime_put(parent); 654 return IRQ_NONE; 655 } 656 657 if (status) { 658 pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, status); 659 660 /* 661 * In MSI mode, all event bits must be zero before the port 662 * will send a new interrupt (PCIe Base Spec r5.0 sec 6.7.3.4). 663 * So re-read the Slot Status register in case a bit was set 664 * between read and write. 665 */ 666 if (pci_dev_msi_enabled(pdev) && !pciehp_poll_mode) 667 goto read_status; 668 } 669 670 ctrl_dbg(ctrl, "pending interrupts %#06x from Slot Status\n", events); 671 if (parent) 672 pm_runtime_put(parent); 673 674 /* 675 * Command Completed notifications are not deferred to the 676 * IRQ thread because it may be waiting for their arrival. 677 */ 678 if (events & PCI_EXP_SLTSTA_CC) { 679 ctrl->cmd_busy = 0; 680 smp_mb(); 681 wake_up(&ctrl->queue); 682 683 if (events == PCI_EXP_SLTSTA_CC) 684 return IRQ_HANDLED; 685 686 events &= ~PCI_EXP_SLTSTA_CC; 687 } 688 689 if (pdev->ignore_hotplug) { 690 ctrl_dbg(ctrl, "ignoring hotplug event %#06x\n", events); 691 return IRQ_HANDLED; 692 } 693 694 /* Save pending events for consumption by IRQ thread. */ 695 atomic_or(events, &ctrl->pending_events); 696 return IRQ_WAKE_THREAD; 697 } 698 699 static irqreturn_t pciehp_ist(int irq, void *dev_id) 700 { 701 struct controller *ctrl = (struct controller *)dev_id; 702 struct pci_dev *pdev = ctrl_dev(ctrl); 703 irqreturn_t ret; 704 u32 events; 705 706 ctrl->ist_running = true; 707 pci_config_pm_runtime_get(pdev); 708 709 /* rerun pciehp_isr() if the port was inaccessible on interrupt */ 710 if (atomic_fetch_and(~RERUN_ISR, &ctrl->pending_events) & RERUN_ISR) { 711 ret = pciehp_isr(irq, dev_id); 712 enable_irq(irq); 713 if (ret != IRQ_WAKE_THREAD) 714 goto out; 715 } 716 717 synchronize_hardirq(irq); 718 events = atomic_xchg(&ctrl->pending_events, 0); 719 if (!events) { 720 ret = IRQ_NONE; 721 goto out; 722 } 723 724 /* Check Attention Button Pressed */ 725 if (events & PCI_EXP_SLTSTA_ABP) 726 pciehp_handle_button_press(ctrl); 727 728 /* Check Power Fault Detected */ 729 if (events & PCI_EXP_SLTSTA_PFD) { 730 ctrl_err(ctrl, "Slot(%s): Power fault\n", slot_name(ctrl)); 731 pciehp_set_indicators(ctrl, PCI_EXP_SLTCTL_PWR_IND_OFF, 732 PCI_EXP_SLTCTL_ATTN_IND_ON); 733 } 734 735 /* 736 * Ignore Link Down/Up events caused by Downstream Port Containment 737 * if recovery from the error succeeded. 738 */ 739 if ((events & PCI_EXP_SLTSTA_DLLSC) && pci_dpc_recovered(pdev) && 740 ctrl->state == ON_STATE) { 741 events &= ~PCI_EXP_SLTSTA_DLLSC; 742 pciehp_ignore_dpc_link_change(ctrl, pdev, irq); 743 } 744 745 /* 746 * Disable requests have higher priority than Presence Detect Changed 747 * or Data Link Layer State Changed events. 748 */ 749 down_read_nested(&ctrl->reset_lock, ctrl->depth); 750 if (events & DISABLE_SLOT) 751 pciehp_handle_disable_request(ctrl); 752 else if (events & (PCI_EXP_SLTSTA_PDC | PCI_EXP_SLTSTA_DLLSC)) 753 pciehp_handle_presence_or_link_change(ctrl, events); 754 up_read(&ctrl->reset_lock); 755 756 ret = IRQ_HANDLED; 757 out: 758 pci_config_pm_runtime_put(pdev); 759 ctrl->ist_running = false; 760 wake_up(&ctrl->requester); 761 return ret; 762 } 763 764 static int pciehp_poll(void *data) 765 { 766 struct controller *ctrl = data; 767 768 schedule_timeout_idle(10 * HZ); /* start with 10 sec delay */ 769 770 while (!kthread_should_stop()) { 771 /* poll for interrupt events or user requests */ 772 while (pciehp_isr(IRQ_NOTCONNECTED, ctrl) == IRQ_WAKE_THREAD || 773 atomic_read(&ctrl->pending_events)) 774 pciehp_ist(IRQ_NOTCONNECTED, ctrl); 775 776 if (pciehp_poll_time <= 0 || pciehp_poll_time > 60) 777 pciehp_poll_time = 2; /* clamp to sane value */ 778 779 schedule_timeout_idle(pciehp_poll_time * HZ); 780 } 781 782 return 0; 783 } 784 785 static void pcie_enable_notification(struct controller *ctrl) 786 { 787 u16 cmd, mask; 788 789 /* 790 * TBD: Power fault detected software notification support. 791 * 792 * Power fault detected software notification is not enabled 793 * now, because it caused power fault detected interrupt storm 794 * on some machines. On those machines, power fault detected 795 * bit in the slot status register was set again immediately 796 * when it is cleared in the interrupt service routine, and 797 * next power fault detected interrupt was notified again. 798 */ 799 800 /* 801 * Always enable link events: thus link-up and link-down shall 802 * always be treated as hotplug and unplug respectively. Enable 803 * presence detect only if Attention Button is not present. 804 */ 805 cmd = PCI_EXP_SLTCTL_DLLSCE; 806 if (ATTN_BUTTN(ctrl)) 807 cmd |= PCI_EXP_SLTCTL_ABPE; 808 else 809 cmd |= PCI_EXP_SLTCTL_PDCE; 810 if (!pciehp_poll_mode) 811 cmd |= PCI_EXP_SLTCTL_HPIE; 812 if (!pciehp_poll_mode && !NO_CMD_CMPL(ctrl)) 813 cmd |= PCI_EXP_SLTCTL_CCIE; 814 815 mask = (PCI_EXP_SLTCTL_PDCE | PCI_EXP_SLTCTL_ABPE | 816 PCI_EXP_SLTCTL_PFDE | 817 PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE | 818 PCI_EXP_SLTCTL_DLLSCE); 819 820 pcie_write_cmd_nowait(ctrl, cmd, mask); 821 ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__, 822 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, cmd); 823 } 824 825 static void pcie_disable_notification(struct controller *ctrl) 826 { 827 u16 mask; 828 829 mask = (PCI_EXP_SLTCTL_PDCE | PCI_EXP_SLTCTL_ABPE | 830 PCI_EXP_SLTCTL_MRLSCE | PCI_EXP_SLTCTL_PFDE | 831 PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE | 832 PCI_EXP_SLTCTL_DLLSCE); 833 pcie_write_cmd(ctrl, 0, mask); 834 ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__, 835 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, 0); 836 } 837 838 void pcie_clear_hotplug_events(struct controller *ctrl) 839 { 840 pcie_capability_write_word(ctrl_dev(ctrl), PCI_EXP_SLTSTA, 841 PCI_EXP_SLTSTA_PDC | PCI_EXP_SLTSTA_DLLSC); 842 } 843 844 void pcie_enable_interrupt(struct controller *ctrl) 845 { 846 u16 mask; 847 848 mask = PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_DLLSCE; 849 pcie_write_cmd(ctrl, mask, mask); 850 } 851 852 void pcie_disable_interrupt(struct controller *ctrl) 853 { 854 u16 mask; 855 856 /* 857 * Mask hot-plug interrupt to prevent it triggering immediately 858 * when the link goes inactive (we still get PME when any of the 859 * enabled events is detected). Same goes with Link Layer State 860 * changed event which generates PME immediately when the link goes 861 * inactive so mask it as well. 862 */ 863 mask = PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_DLLSCE; 864 pcie_write_cmd(ctrl, 0, mask); 865 } 866 867 /** 868 * pciehp_slot_reset() - ignore link event caused by error-induced hot reset 869 * @dev: PCI Express port service device 870 * 871 * Called from pcie_portdrv_slot_reset() after AER or DPC initiated a reset 872 * further up in the hierarchy to recover from an error. The reset was 873 * propagated down to this hotplug port. Ignore the resulting link flap. 874 * If the link failed to retrain successfully, synthesize the ignored event. 875 * Surprise removal during reset is detected through Presence Detect Changed. 876 */ 877 int pciehp_slot_reset(struct pcie_device *dev) 878 { 879 struct controller *ctrl = get_service_data(dev); 880 881 if (ctrl->state != ON_STATE) 882 return 0; 883 884 pcie_capability_write_word(dev->port, PCI_EXP_SLTSTA, 885 PCI_EXP_SLTSTA_DLLSC); 886 887 if (!pciehp_check_link_active(ctrl)) 888 pciehp_request(ctrl, PCI_EXP_SLTSTA_DLLSC); 889 890 return 0; 891 } 892 893 /* 894 * pciehp has a 1:1 bus:slot relationship so we ultimately want a secondary 895 * bus reset of the bridge, but at the same time we want to ensure that it is 896 * not seen as a hot-unplug, followed by the hot-plug of the device. Thus, 897 * disable link state notification and presence detection change notification 898 * momentarily, if we see that they could interfere. Also, clear any spurious 899 * events after. 900 */ 901 int pciehp_reset_slot(struct hotplug_slot *hotplug_slot, bool probe) 902 { 903 struct controller *ctrl = to_ctrl(hotplug_slot); 904 struct pci_dev *pdev = ctrl_dev(ctrl); 905 u16 stat_mask = 0, ctrl_mask = 0; 906 int rc; 907 908 if (probe) 909 return 0; 910 911 down_write_nested(&ctrl->reset_lock, ctrl->depth); 912 913 if (!ATTN_BUTTN(ctrl)) { 914 ctrl_mask |= PCI_EXP_SLTCTL_PDCE; 915 stat_mask |= PCI_EXP_SLTSTA_PDC; 916 } 917 ctrl_mask |= PCI_EXP_SLTCTL_DLLSCE; 918 stat_mask |= PCI_EXP_SLTSTA_DLLSC; 919 920 pcie_write_cmd(ctrl, 0, ctrl_mask); 921 ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__, 922 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, 0); 923 924 rc = pci_bridge_secondary_bus_reset(ctrl->pcie->port); 925 926 pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, stat_mask); 927 pcie_write_cmd_nowait(ctrl, ctrl_mask, ctrl_mask); 928 ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__, 929 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, ctrl_mask); 930 931 up_write(&ctrl->reset_lock); 932 return rc; 933 } 934 935 int pcie_init_notification(struct controller *ctrl) 936 { 937 if (pciehp_request_irq(ctrl)) 938 return -1; 939 pcie_enable_notification(ctrl); 940 ctrl->notification_enabled = 1; 941 return 0; 942 } 943 944 void pcie_shutdown_notification(struct controller *ctrl) 945 { 946 if (ctrl->notification_enabled) { 947 pcie_disable_notification(ctrl); 948 pciehp_free_irq(ctrl); 949 ctrl->notification_enabled = 0; 950 } 951 } 952 953 static inline void dbg_ctrl(struct controller *ctrl) 954 { 955 struct pci_dev *pdev = ctrl->pcie->port; 956 u16 reg16; 957 958 ctrl_dbg(ctrl, "Slot Capabilities : 0x%08x\n", ctrl->slot_cap); 959 pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, ®16); 960 ctrl_dbg(ctrl, "Slot Status : 0x%04x\n", reg16); 961 pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, ®16); 962 ctrl_dbg(ctrl, "Slot Control : 0x%04x\n", reg16); 963 } 964 965 #define FLAG(x, y) (((x) & (y)) ? '+' : '-') 966 967 static inline int pcie_hotplug_depth(struct pci_dev *dev) 968 { 969 struct pci_bus *bus = dev->bus; 970 int depth = 0; 971 972 while (bus->parent) { 973 bus = bus->parent; 974 if (bus->self && bus->self->is_hotplug_bridge) 975 depth++; 976 } 977 978 return depth; 979 } 980 981 struct controller *pcie_init(struct pcie_device *dev) 982 { 983 struct controller *ctrl; 984 u32 slot_cap, slot_cap2; 985 u8 poweron; 986 struct pci_dev *pdev = dev->port; 987 struct pci_bus *subordinate = pdev->subordinate; 988 989 ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL); 990 if (!ctrl) 991 return NULL; 992 993 ctrl->pcie = dev; 994 ctrl->depth = pcie_hotplug_depth(dev->port); 995 pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, &slot_cap); 996 997 if (pdev->hotplug_user_indicators) 998 slot_cap &= ~(PCI_EXP_SLTCAP_AIP | PCI_EXP_SLTCAP_PIP); 999 1000 /* 1001 * We assume no Thunderbolt controllers support Command Complete events, 1002 * but some controllers falsely claim they do. 1003 */ 1004 if (pdev->is_thunderbolt) 1005 slot_cap |= PCI_EXP_SLTCAP_NCCS; 1006 1007 ctrl->slot_cap = slot_cap; 1008 mutex_init(&ctrl->ctrl_lock); 1009 mutex_init(&ctrl->state_lock); 1010 init_rwsem(&ctrl->reset_lock); 1011 init_waitqueue_head(&ctrl->requester); 1012 init_waitqueue_head(&ctrl->queue); 1013 INIT_DELAYED_WORK(&ctrl->button_work, pciehp_queue_pushbutton_work); 1014 dbg_ctrl(ctrl); 1015 1016 down_read(&pci_bus_sem); 1017 ctrl->state = list_empty(&subordinate->devices) ? OFF_STATE : ON_STATE; 1018 up_read(&pci_bus_sem); 1019 1020 pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP2, &slot_cap2); 1021 if (slot_cap2 & PCI_EXP_SLTCAP2_IBPD) { 1022 pcie_write_cmd_nowait(ctrl, PCI_EXP_SLTCTL_IBPD_DISABLE, 1023 PCI_EXP_SLTCTL_IBPD_DISABLE); 1024 ctrl->inband_presence_disabled = 1; 1025 } 1026 1027 if (dmi_first_match(inband_presence_disabled_dmi_table)) 1028 ctrl->inband_presence_disabled = 1; 1029 1030 /* Clear all remaining event bits in Slot Status register. */ 1031 pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, 1032 PCI_EXP_SLTSTA_ABP | PCI_EXP_SLTSTA_PFD | 1033 PCI_EXP_SLTSTA_MRLSC | PCI_EXP_SLTSTA_CC | 1034 PCI_EXP_SLTSTA_DLLSC | PCI_EXP_SLTSTA_PDC); 1035 1036 ctrl_info(ctrl, "Slot #%d AttnBtn%c PwrCtrl%c MRL%c AttnInd%c PwrInd%c HotPlug%c Surprise%c Interlock%c NoCompl%c IbPresDis%c LLActRep%c%s\n", 1037 (slot_cap & PCI_EXP_SLTCAP_PSN) >> 19, 1038 FLAG(slot_cap, PCI_EXP_SLTCAP_ABP), 1039 FLAG(slot_cap, PCI_EXP_SLTCAP_PCP), 1040 FLAG(slot_cap, PCI_EXP_SLTCAP_MRLSP), 1041 FLAG(slot_cap, PCI_EXP_SLTCAP_AIP), 1042 FLAG(slot_cap, PCI_EXP_SLTCAP_PIP), 1043 FLAG(slot_cap, PCI_EXP_SLTCAP_HPC), 1044 FLAG(slot_cap, PCI_EXP_SLTCAP_HPS), 1045 FLAG(slot_cap, PCI_EXP_SLTCAP_EIP), 1046 FLAG(slot_cap, PCI_EXP_SLTCAP_NCCS), 1047 FLAG(slot_cap2, PCI_EXP_SLTCAP2_IBPD), 1048 FLAG(pdev->link_active_reporting, true), 1049 pdev->broken_cmd_compl ? " (with Cmd Compl erratum)" : ""); 1050 1051 /* 1052 * If empty slot's power status is on, turn power off. The IRQ isn't 1053 * requested yet, so avoid triggering a notification with this command. 1054 */ 1055 if (POWER_CTRL(ctrl)) { 1056 pciehp_get_power_status(ctrl, &poweron); 1057 if (!pciehp_card_present_or_link_active(ctrl) && poweron) { 1058 pcie_disable_notification(ctrl); 1059 pciehp_power_off_slot(ctrl); 1060 } 1061 } 1062 1063 return ctrl; 1064 } 1065 1066 void pciehp_release_ctrl(struct controller *ctrl) 1067 { 1068 cancel_delayed_work_sync(&ctrl->button_work); 1069 kfree(ctrl); 1070 } 1071 1072 static void quirk_cmd_compl(struct pci_dev *pdev) 1073 { 1074 u32 slot_cap; 1075 1076 if (pci_is_pcie(pdev)) { 1077 pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, &slot_cap); 1078 if (slot_cap & PCI_EXP_SLTCAP_HPC && 1079 !(slot_cap & PCI_EXP_SLTCAP_NCCS)) 1080 pdev->broken_cmd_compl = 1; 1081 } 1082 } 1083 DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_VENDOR_ID_INTEL, PCI_ANY_ID, 1084 PCI_CLASS_BRIDGE_PCI, 8, quirk_cmd_compl); 1085 DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_VENDOR_ID_QCOM, 0x010e, 1086 PCI_CLASS_BRIDGE_PCI, 8, quirk_cmd_compl); 1087 DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_VENDOR_ID_QCOM, 0x0110, 1088 PCI_CLASS_BRIDGE_PCI, 8, quirk_cmd_compl); 1089 DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_VENDOR_ID_QCOM, 0x0400, 1090 PCI_CLASS_BRIDGE_PCI, 8, quirk_cmd_compl); 1091 DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_VENDOR_ID_QCOM, 0x0401, 1092 PCI_CLASS_BRIDGE_PCI, 8, quirk_cmd_compl); 1093 DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_VENDOR_ID_HXT, 0x0401, 1094 PCI_CLASS_BRIDGE_PCI, 8, quirk_cmd_compl); 1095