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