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v5.4
  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/kernel.h>
 18#include <linux/types.h>
 19#include <linux/jiffies.h>
 20#include <linux/kthread.h>
 21#include <linux/pci.h>
 22#include <linux/pm_runtime.h>
 23#include <linux/interrupt.h>
 24#include <linux/slab.h>
 25
 26#include "../pci.h"
 27#include "pciehp.h"
 28
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 29static inline struct pci_dev *ctrl_dev(struct controller *ctrl)
 30{
 31	return ctrl->pcie->port;
 32}
 33
 34static irqreturn_t pciehp_isr(int irq, void *dev_id);
 35static irqreturn_t pciehp_ist(int irq, void *dev_id);
 36static int pciehp_poll(void *data);
 37
 38static inline int pciehp_request_irq(struct controller *ctrl)
 39{
 40	int retval, irq = ctrl->pcie->irq;
 41
 42	if (pciehp_poll_mode) {
 43		ctrl->poll_thread = kthread_run(&pciehp_poll, ctrl,
 44						"pciehp_poll-%s",
 45						slot_name(ctrl));
 46		return PTR_ERR_OR_ZERO(ctrl->poll_thread);
 47	}
 48
 49	/* Installs the interrupt handler */
 50	retval = request_threaded_irq(irq, pciehp_isr, pciehp_ist,
 51				      IRQF_SHARED, "pciehp", ctrl);
 52	if (retval)
 53		ctrl_err(ctrl, "Cannot get irq %d for the hotplug controller\n",
 54			 irq);
 55	return retval;
 56}
 57
 58static inline void pciehp_free_irq(struct controller *ctrl)
 59{
 60	if (pciehp_poll_mode)
 61		kthread_stop(ctrl->poll_thread);
 62	else
 63		free_irq(ctrl->pcie->irq, ctrl);
 64}
 65
 66static int pcie_poll_cmd(struct controller *ctrl, int timeout)
 67{
 68	struct pci_dev *pdev = ctrl_dev(ctrl);
 69	u16 slot_status;
 70
 71	while (true) {
 72		pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
 73		if (slot_status == (u16) ~0) {
 74			ctrl_info(ctrl, "%s: no response from device\n",
 75				  __func__);
 76			return 0;
 77		}
 78
 79		if (slot_status & PCI_EXP_SLTSTA_CC) {
 80			pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
 81						   PCI_EXP_SLTSTA_CC);
 82			return 1;
 83		}
 84		if (timeout < 0)
 85			break;
 86		msleep(10);
 87		timeout -= 10;
 88	}
 89	return 0;	/* timeout */
 90}
 91
 92static void pcie_wait_cmd(struct controller *ctrl)
 93{
 94	unsigned int msecs = pciehp_poll_mode ? 2500 : 1000;
 95	unsigned long duration = msecs_to_jiffies(msecs);
 96	unsigned long cmd_timeout = ctrl->cmd_started + duration;
 97	unsigned long now, timeout;
 98	int rc;
 99
100	/*
101	 * If the controller does not generate notifications for command
102	 * completions, we never need to wait between writes.
103	 */
104	if (NO_CMD_CMPL(ctrl))
105		return;
106
107	if (!ctrl->cmd_busy)
108		return;
109
110	/*
111	 * Even if the command has already timed out, we want to call
112	 * pcie_poll_cmd() so it can clear PCI_EXP_SLTSTA_CC.
113	 */
114	now = jiffies;
115	if (time_before_eq(cmd_timeout, now))
116		timeout = 1;
117	else
118		timeout = cmd_timeout - now;
119
120	if (ctrl->slot_ctrl & PCI_EXP_SLTCTL_HPIE &&
121	    ctrl->slot_ctrl & PCI_EXP_SLTCTL_CCIE)
122		rc = wait_event_timeout(ctrl->queue, !ctrl->cmd_busy, timeout);
123	else
124		rc = pcie_poll_cmd(ctrl, jiffies_to_msecs(timeout));
125
126	if (!rc)
127		ctrl_info(ctrl, "Timeout on hotplug command %#06x (issued %u msec ago)\n",
128			  ctrl->slot_ctrl,
129			  jiffies_to_msecs(jiffies - ctrl->cmd_started));
130}
131
132#define CC_ERRATUM_MASK		(PCI_EXP_SLTCTL_PCC |	\
133				 PCI_EXP_SLTCTL_PIC |	\
134				 PCI_EXP_SLTCTL_AIC |	\
135				 PCI_EXP_SLTCTL_EIC)
136
137static void pcie_do_write_cmd(struct controller *ctrl, u16 cmd,
138			      u16 mask, bool wait)
139{
140	struct pci_dev *pdev = ctrl_dev(ctrl);
141	u16 slot_ctrl_orig, slot_ctrl;
142
143	mutex_lock(&ctrl->ctrl_lock);
144
145	/*
146	 * Always wait for any previous command that might still be in progress
147	 */
148	pcie_wait_cmd(ctrl);
149
150	pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &slot_ctrl);
151	if (slot_ctrl == (u16) ~0) {
152		ctrl_info(ctrl, "%s: no response from device\n", __func__);
153		goto out;
154	}
155
156	slot_ctrl_orig = slot_ctrl;
157	slot_ctrl &= ~mask;
158	slot_ctrl |= (cmd & mask);
159	ctrl->cmd_busy = 1;
160	smp_mb();
161	ctrl->slot_ctrl = slot_ctrl;
162	pcie_capability_write_word(pdev, PCI_EXP_SLTCTL, slot_ctrl);
163	ctrl->cmd_started = jiffies;
164
165	/*
166	 * Controllers with the Intel CF118 and similar errata advertise
167	 * Command Completed support, but they only set Command Completed
168	 * if we change the "Control" bits for power, power indicator,
169	 * attention indicator, or interlock.  If we only change the
170	 * "Enable" bits, they never set the Command Completed bit.
171	 */
172	if (pdev->broken_cmd_compl &&
173	    (slot_ctrl_orig & CC_ERRATUM_MASK) == (slot_ctrl & CC_ERRATUM_MASK))
174		ctrl->cmd_busy = 0;
175
176	/*
177	 * Optionally wait for the hardware to be ready for a new command,
178	 * indicating completion of the above issued command.
179	 */
180	if (wait)
181		pcie_wait_cmd(ctrl);
182
183out:
184	mutex_unlock(&ctrl->ctrl_lock);
185}
186
187/**
188 * pcie_write_cmd - Issue controller command
189 * @ctrl: controller to which the command is issued
190 * @cmd:  command value written to slot control register
191 * @mask: bitmask of slot control register to be modified
192 */
193static void pcie_write_cmd(struct controller *ctrl, u16 cmd, u16 mask)
194{
195	pcie_do_write_cmd(ctrl, cmd, mask, true);
196}
197
198/* Same as above without waiting for the hardware to latch */
199static void pcie_write_cmd_nowait(struct controller *ctrl, u16 cmd, u16 mask)
200{
201	pcie_do_write_cmd(ctrl, cmd, mask, false);
202}
203
204bool pciehp_check_link_active(struct controller *ctrl)
 
 
 
 
 
 
 
 
 
 
 
205{
206	struct pci_dev *pdev = ctrl_dev(ctrl);
207	u16 lnk_status;
208	bool ret;
209
210	pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status);
211	ret = !!(lnk_status & PCI_EXP_LNKSTA_DLLLA);
 
212
213	if (ret)
214		ctrl_dbg(ctrl, "%s: lnk_status = %x\n", __func__, lnk_status);
215
216	return ret;
217}
218
219static bool pci_bus_check_dev(struct pci_bus *bus, int devfn)
220{
221	u32 l;
222	int count = 0;
223	int delay = 1000, step = 20;
224	bool found = false;
225
226	do {
227		found = pci_bus_read_dev_vendor_id(bus, devfn, &l, 0);
228		count++;
229
230		if (found)
231			break;
232
233		msleep(step);
234		delay -= step;
235	} while (delay > 0);
236
237	if (count > 1)
238		pr_debug("pci %04x:%02x:%02x.%d id reading try %d times with interval %d ms to get %08x\n",
239			pci_domain_nr(bus), bus->number, PCI_SLOT(devfn),
240			PCI_FUNC(devfn), count, step, l);
241
242	return found;
243}
244
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
245int pciehp_check_link_status(struct controller *ctrl)
246{
247	struct pci_dev *pdev = ctrl_dev(ctrl);
248	bool found;
249	u16 lnk_status;
250
251	if (!pcie_wait_for_link(pdev, true))
252		return -1;
253
 
 
 
254	found = pci_bus_check_dev(ctrl->pcie->port->subordinate,
255					PCI_DEVFN(0, 0));
256
257	/* ignore link or presence changes up to this point */
258	if (found)
259		atomic_and(~(PCI_EXP_SLTSTA_DLLSC | PCI_EXP_SLTSTA_PDC),
260			   &ctrl->pending_events);
261
262	pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status);
263	ctrl_dbg(ctrl, "%s: lnk_status = %x\n", __func__, lnk_status);
264	if ((lnk_status & PCI_EXP_LNKSTA_LT) ||
265	    !(lnk_status & PCI_EXP_LNKSTA_NLW)) {
266		ctrl_err(ctrl, "link training error: status %#06x\n",
267			 lnk_status);
268		return -1;
269	}
270
271	pcie_update_link_speed(ctrl->pcie->port->subordinate, lnk_status);
272
273	if (!found)
274		return -1;
275
276	return 0;
277}
278
279static int __pciehp_link_set(struct controller *ctrl, bool enable)
280{
281	struct pci_dev *pdev = ctrl_dev(ctrl);
282	u16 lnk_ctrl;
283
284	pcie_capability_read_word(pdev, PCI_EXP_LNKCTL, &lnk_ctrl);
285
286	if (enable)
287		lnk_ctrl &= ~PCI_EXP_LNKCTL_LD;
288	else
289		lnk_ctrl |= PCI_EXP_LNKCTL_LD;
290
291	pcie_capability_write_word(pdev, PCI_EXP_LNKCTL, lnk_ctrl);
292	ctrl_dbg(ctrl, "%s: lnk_ctrl = %x\n", __func__, lnk_ctrl);
293	return 0;
294}
295
296static int pciehp_link_enable(struct controller *ctrl)
297{
298	return __pciehp_link_set(ctrl, true);
299}
300
301int pciehp_get_raw_indicator_status(struct hotplug_slot *hotplug_slot,
302				    u8 *status)
303{
304	struct controller *ctrl = to_ctrl(hotplug_slot);
305	struct pci_dev *pdev = ctrl_dev(ctrl);
306	u16 slot_ctrl;
307
308	pci_config_pm_runtime_get(pdev);
309	pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &slot_ctrl);
310	pci_config_pm_runtime_put(pdev);
311	*status = (slot_ctrl & (PCI_EXP_SLTCTL_AIC | PCI_EXP_SLTCTL_PIC)) >> 6;
312	return 0;
313}
314
315int pciehp_get_attention_status(struct hotplug_slot *hotplug_slot, u8 *status)
316{
317	struct controller *ctrl = to_ctrl(hotplug_slot);
318	struct pci_dev *pdev = ctrl_dev(ctrl);
319	u16 slot_ctrl;
320
321	pci_config_pm_runtime_get(pdev);
322	pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &slot_ctrl);
323	pci_config_pm_runtime_put(pdev);
324	ctrl_dbg(ctrl, "%s: SLOTCTRL %x, value read %x\n", __func__,
325		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_ctrl);
326
327	switch (slot_ctrl & PCI_EXP_SLTCTL_AIC) {
328	case PCI_EXP_SLTCTL_ATTN_IND_ON:
329		*status = 1;	/* On */
330		break;
331	case PCI_EXP_SLTCTL_ATTN_IND_BLINK:
332		*status = 2;	/* Blink */
333		break;
334	case PCI_EXP_SLTCTL_ATTN_IND_OFF:
335		*status = 0;	/* Off */
336		break;
337	default:
338		*status = 0xFF;
339		break;
340	}
341
342	return 0;
343}
344
345void pciehp_get_power_status(struct controller *ctrl, u8 *status)
346{
347	struct pci_dev *pdev = ctrl_dev(ctrl);
348	u16 slot_ctrl;
349
350	pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &slot_ctrl);
351	ctrl_dbg(ctrl, "%s: SLOTCTRL %x value read %x\n", __func__,
352		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_ctrl);
353
354	switch (slot_ctrl & PCI_EXP_SLTCTL_PCC) {
355	case PCI_EXP_SLTCTL_PWR_ON:
356		*status = 1;	/* On */
357		break;
358	case PCI_EXP_SLTCTL_PWR_OFF:
359		*status = 0;	/* Off */
360		break;
361	default:
362		*status = 0xFF;
363		break;
364	}
365}
366
367void pciehp_get_latch_status(struct controller *ctrl, u8 *status)
368{
369	struct pci_dev *pdev = ctrl_dev(ctrl);
370	u16 slot_status;
371
372	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
373	*status = !!(slot_status & PCI_EXP_SLTSTA_MRLSS);
374}
375
376bool pciehp_card_present(struct controller *ctrl)
 
 
 
 
 
 
 
 
 
 
 
 
377{
378	struct pci_dev *pdev = ctrl_dev(ctrl);
379	u16 slot_status;
 
380
381	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
382	return slot_status & PCI_EXP_SLTSTA_PDS;
 
 
 
383}
384
385/**
386 * pciehp_card_present_or_link_active() - whether given slot is occupied
387 * @ctrl: PCIe hotplug controller
388 *
389 * Unlike pciehp_card_present(), which determines presence solely from the
390 * Presence Detect State bit, this helper also returns true if the Link Active
391 * bit is set.  This is a concession to broken hotplug ports which hardwire
392 * Presence Detect State to zero, such as Wilocity's [1ae9:0200].
 
 
 
393 */
394bool pciehp_card_present_or_link_active(struct controller *ctrl)
395{
396	return pciehp_card_present(ctrl) || pciehp_check_link_active(ctrl);
 
 
 
 
 
 
397}
398
399int pciehp_query_power_fault(struct controller *ctrl)
400{
401	struct pci_dev *pdev = ctrl_dev(ctrl);
402	u16 slot_status;
403
404	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
405	return !!(slot_status & PCI_EXP_SLTSTA_PFD);
406}
407
408int pciehp_set_raw_indicator_status(struct hotplug_slot *hotplug_slot,
409				    u8 status)
410{
411	struct controller *ctrl = to_ctrl(hotplug_slot);
412	struct pci_dev *pdev = ctrl_dev(ctrl);
413
414	pci_config_pm_runtime_get(pdev);
415	pcie_write_cmd_nowait(ctrl, status << 6,
416			      PCI_EXP_SLTCTL_AIC | PCI_EXP_SLTCTL_PIC);
417	pci_config_pm_runtime_put(pdev);
418	return 0;
419}
420
421/**
422 * pciehp_set_indicators() - set attention indicator, power indicator, or both
423 * @ctrl: PCIe hotplug controller
424 * @pwr: one of:
425 *	PCI_EXP_SLTCTL_PWR_IND_ON
426 *	PCI_EXP_SLTCTL_PWR_IND_BLINK
427 *	PCI_EXP_SLTCTL_PWR_IND_OFF
428 * @attn: one of:
429 *	PCI_EXP_SLTCTL_ATTN_IND_ON
430 *	PCI_EXP_SLTCTL_ATTN_IND_BLINK
431 *	PCI_EXP_SLTCTL_ATTN_IND_OFF
432 *
433 * Either @pwr or @attn can also be INDICATOR_NOOP to leave that indicator
434 * unchanged.
435 */
436void pciehp_set_indicators(struct controller *ctrl, int pwr, int attn)
437{
438	u16 cmd = 0, mask = 0;
439
440	if (PWR_LED(ctrl) && pwr != INDICATOR_NOOP) {
441		cmd |= (pwr & PCI_EXP_SLTCTL_PIC);
442		mask |= PCI_EXP_SLTCTL_PIC;
443	}
444
445	if (ATTN_LED(ctrl) && attn != INDICATOR_NOOP) {
446		cmd |= (attn & PCI_EXP_SLTCTL_AIC);
447		mask |= PCI_EXP_SLTCTL_AIC;
448	}
449
450	if (cmd) {
451		pcie_write_cmd_nowait(ctrl, cmd, mask);
452		ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
453			 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, cmd);
454	}
455}
456
457int pciehp_power_on_slot(struct controller *ctrl)
458{
459	struct pci_dev *pdev = ctrl_dev(ctrl);
460	u16 slot_status;
461	int retval;
462
463	/* Clear power-fault bit from previous power failures */
464	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
465	if (slot_status & PCI_EXP_SLTSTA_PFD)
466		pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
467					   PCI_EXP_SLTSTA_PFD);
468	ctrl->power_fault_detected = 0;
469
470	pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_PWR_ON, PCI_EXP_SLTCTL_PCC);
471	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
472		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL,
473		 PCI_EXP_SLTCTL_PWR_ON);
474
475	retval = pciehp_link_enable(ctrl);
476	if (retval)
477		ctrl_err(ctrl, "%s: Can not enable the link!\n", __func__);
478
479	return retval;
480}
481
482void pciehp_power_off_slot(struct controller *ctrl)
483{
484	pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_PWR_OFF, PCI_EXP_SLTCTL_PCC);
485	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
486		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL,
487		 PCI_EXP_SLTCTL_PWR_OFF);
488}
489
490static irqreturn_t pciehp_isr(int irq, void *dev_id)
491{
492	struct controller *ctrl = (struct controller *)dev_id;
493	struct pci_dev *pdev = ctrl_dev(ctrl);
494	struct device *parent = pdev->dev.parent;
495	u16 status, events;
496
497	/*
498	 * Interrupts only occur in D3hot or shallower and only if enabled
499	 * in the Slot Control register (PCIe r4.0, sec 6.7.3.4).
500	 */
501	if (pdev->current_state == PCI_D3cold ||
502	    (!(ctrl->slot_ctrl & PCI_EXP_SLTCTL_HPIE) && !pciehp_poll_mode))
503		return IRQ_NONE;
504
505	/*
506	 * Keep the port accessible by holding a runtime PM ref on its parent.
507	 * Defer resume of the parent to the IRQ thread if it's suspended.
508	 * Mask the interrupt until then.
509	 */
510	if (parent) {
511		pm_runtime_get_noresume(parent);
512		if (!pm_runtime_active(parent)) {
513			pm_runtime_put(parent);
514			disable_irq_nosync(irq);
515			atomic_or(RERUN_ISR, &ctrl->pending_events);
516			return IRQ_WAKE_THREAD;
517		}
518	}
519
 
520	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &status);
521	if (status == (u16) ~0) {
522		ctrl_info(ctrl, "%s: no response from device\n", __func__);
523		if (parent)
524			pm_runtime_put(parent);
525		return IRQ_NONE;
526	}
527
528	/*
529	 * Slot Status contains plain status bits as well as event
530	 * notification bits; right now we only want the event bits.
531	 */
532	events = status & (PCI_EXP_SLTSTA_ABP | PCI_EXP_SLTSTA_PFD |
533			   PCI_EXP_SLTSTA_PDC | PCI_EXP_SLTSTA_CC |
534			   PCI_EXP_SLTSTA_DLLSC);
535
536	/*
537	 * If we've already reported a power fault, don't report it again
538	 * until we've done something to handle it.
539	 */
540	if (ctrl->power_fault_detected)
541		events &= ~PCI_EXP_SLTSTA_PFD;
542
 
543	if (!events) {
544		if (parent)
545			pm_runtime_put(parent);
546		return IRQ_NONE;
547	}
548
549	pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, events);
 
 
 
 
 
 
 
 
 
 
 
 
550	ctrl_dbg(ctrl, "pending interrupts %#06x from Slot Status\n", events);
551	if (parent)
552		pm_runtime_put(parent);
553
554	/*
555	 * Command Completed notifications are not deferred to the
556	 * IRQ thread because it may be waiting for their arrival.
557	 */
558	if (events & PCI_EXP_SLTSTA_CC) {
559		ctrl->cmd_busy = 0;
560		smp_mb();
561		wake_up(&ctrl->queue);
562
563		if (events == PCI_EXP_SLTSTA_CC)
564			return IRQ_HANDLED;
565
566		events &= ~PCI_EXP_SLTSTA_CC;
567	}
568
569	if (pdev->ignore_hotplug) {
570		ctrl_dbg(ctrl, "ignoring hotplug event %#06x\n", events);
571		return IRQ_HANDLED;
572	}
573
574	/* Save pending events for consumption by IRQ thread. */
575	atomic_or(events, &ctrl->pending_events);
576	return IRQ_WAKE_THREAD;
577}
578
579static irqreturn_t pciehp_ist(int irq, void *dev_id)
580{
581	struct controller *ctrl = (struct controller *)dev_id;
582	struct pci_dev *pdev = ctrl_dev(ctrl);
583	irqreturn_t ret;
584	u32 events;
585
 
586	pci_config_pm_runtime_get(pdev);
587
588	/* rerun pciehp_isr() if the port was inaccessible on interrupt */
589	if (atomic_fetch_and(~RERUN_ISR, &ctrl->pending_events) & RERUN_ISR) {
590		ret = pciehp_isr(irq, dev_id);
591		enable_irq(irq);
592		if (ret != IRQ_WAKE_THREAD) {
593			pci_config_pm_runtime_put(pdev);
594			return ret;
595		}
596	}
597
598	synchronize_hardirq(irq);
599	events = atomic_xchg(&ctrl->pending_events, 0);
600	if (!events) {
601		pci_config_pm_runtime_put(pdev);
602		return IRQ_NONE;
603	}
604
605	/* Check Attention Button Pressed */
606	if (events & PCI_EXP_SLTSTA_ABP) {
607		ctrl_info(ctrl, "Slot(%s): Attention button pressed\n",
608			  slot_name(ctrl));
609		pciehp_handle_button_press(ctrl);
610	}
611
612	/* Check Power Fault Detected */
613	if ((events & PCI_EXP_SLTSTA_PFD) && !ctrl->power_fault_detected) {
614		ctrl->power_fault_detected = 1;
615		ctrl_err(ctrl, "Slot(%s): Power fault\n", slot_name(ctrl));
616		pciehp_set_indicators(ctrl, PCI_EXP_SLTCTL_PWR_IND_OFF,
617				      PCI_EXP_SLTCTL_ATTN_IND_ON);
618	}
619
620	/*
621	 * Disable requests have higher priority than Presence Detect Changed
622	 * or Data Link Layer State Changed events.
623	 */
624	down_read(&ctrl->reset_lock);
625	if (events & DISABLE_SLOT)
626		pciehp_handle_disable_request(ctrl);
627	else if (events & (PCI_EXP_SLTSTA_PDC | PCI_EXP_SLTSTA_DLLSC))
628		pciehp_handle_presence_or_link_change(ctrl, events);
629	up_read(&ctrl->reset_lock);
630
 
 
631	pci_config_pm_runtime_put(pdev);
 
632	wake_up(&ctrl->requester);
633	return IRQ_HANDLED;
634}
635
636static int pciehp_poll(void *data)
637{
638	struct controller *ctrl = data;
639
640	schedule_timeout_idle(10 * HZ); /* start with 10 sec delay */
641
642	while (!kthread_should_stop()) {
643		/* poll for interrupt events or user requests */
644		while (pciehp_isr(IRQ_NOTCONNECTED, ctrl) == IRQ_WAKE_THREAD ||
645		       atomic_read(&ctrl->pending_events))
646			pciehp_ist(IRQ_NOTCONNECTED, ctrl);
647
648		if (pciehp_poll_time <= 0 || pciehp_poll_time > 60)
649			pciehp_poll_time = 2; /* clamp to sane value */
650
651		schedule_timeout_idle(pciehp_poll_time * HZ);
652	}
653
654	return 0;
655}
656
657static void pcie_enable_notification(struct controller *ctrl)
658{
659	u16 cmd, mask;
660
661	/*
662	 * TBD: Power fault detected software notification support.
663	 *
664	 * Power fault detected software notification is not enabled
665	 * now, because it caused power fault detected interrupt storm
666	 * on some machines. On those machines, power fault detected
667	 * bit in the slot status register was set again immediately
668	 * when it is cleared in the interrupt service routine, and
669	 * next power fault detected interrupt was notified again.
670	 */
671
672	/*
673	 * Always enable link events: thus link-up and link-down shall
674	 * always be treated as hotplug and unplug respectively. Enable
675	 * presence detect only if Attention Button is not present.
676	 */
677	cmd = PCI_EXP_SLTCTL_DLLSCE;
678	if (ATTN_BUTTN(ctrl))
679		cmd |= PCI_EXP_SLTCTL_ABPE;
680	else
681		cmd |= PCI_EXP_SLTCTL_PDCE;
682	if (!pciehp_poll_mode)
683		cmd |= PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE;
684
685	mask = (PCI_EXP_SLTCTL_PDCE | PCI_EXP_SLTCTL_ABPE |
686		PCI_EXP_SLTCTL_PFDE |
687		PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE |
688		PCI_EXP_SLTCTL_DLLSCE);
689
690	pcie_write_cmd_nowait(ctrl, cmd, mask);
691	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
692		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, cmd);
693}
694
695static void pcie_disable_notification(struct controller *ctrl)
696{
697	u16 mask;
698
699	mask = (PCI_EXP_SLTCTL_PDCE | PCI_EXP_SLTCTL_ABPE |
700		PCI_EXP_SLTCTL_MRLSCE | PCI_EXP_SLTCTL_PFDE |
701		PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE |
702		PCI_EXP_SLTCTL_DLLSCE);
703	pcie_write_cmd(ctrl, 0, mask);
704	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
705		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, 0);
706}
707
708void pcie_clear_hotplug_events(struct controller *ctrl)
709{
710	pcie_capability_write_word(ctrl_dev(ctrl), PCI_EXP_SLTSTA,
711				   PCI_EXP_SLTSTA_PDC | PCI_EXP_SLTSTA_DLLSC);
712}
713
714void pcie_enable_interrupt(struct controller *ctrl)
715{
716	u16 mask;
717
718	mask = PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_DLLSCE;
719	pcie_write_cmd(ctrl, mask, mask);
720}
721
722void pcie_disable_interrupt(struct controller *ctrl)
723{
724	u16 mask;
725
726	/*
727	 * Mask hot-plug interrupt to prevent it triggering immediately
728	 * when the link goes inactive (we still get PME when any of the
729	 * enabled events is detected). Same goes with Link Layer State
730	 * changed event which generates PME immediately when the link goes
731	 * inactive so mask it as well.
732	 */
733	mask = PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_DLLSCE;
734	pcie_write_cmd(ctrl, 0, mask);
735}
736
737/*
738 * pciehp has a 1:1 bus:slot relationship so we ultimately want a secondary
739 * bus reset of the bridge, but at the same time we want to ensure that it is
740 * not seen as a hot-unplug, followed by the hot-plug of the device. Thus,
741 * disable link state notification and presence detection change notification
742 * momentarily, if we see that they could interfere. Also, clear any spurious
743 * events after.
744 */
745int pciehp_reset_slot(struct hotplug_slot *hotplug_slot, int probe)
746{
747	struct controller *ctrl = to_ctrl(hotplug_slot);
748	struct pci_dev *pdev = ctrl_dev(ctrl);
749	u16 stat_mask = 0, ctrl_mask = 0;
750	int rc;
751
752	if (probe)
753		return 0;
754
755	down_write(&ctrl->reset_lock);
756
757	if (!ATTN_BUTTN(ctrl)) {
758		ctrl_mask |= PCI_EXP_SLTCTL_PDCE;
759		stat_mask |= PCI_EXP_SLTSTA_PDC;
760	}
761	ctrl_mask |= PCI_EXP_SLTCTL_DLLSCE;
762	stat_mask |= PCI_EXP_SLTSTA_DLLSC;
763
764	pcie_write_cmd(ctrl, 0, ctrl_mask);
765	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
766		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, 0);
767
768	rc = pci_bridge_secondary_bus_reset(ctrl->pcie->port);
769
770	pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, stat_mask);
771	pcie_write_cmd_nowait(ctrl, ctrl_mask, ctrl_mask);
772	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
773		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, ctrl_mask);
774
775	up_write(&ctrl->reset_lock);
776	return rc;
777}
778
779int pcie_init_notification(struct controller *ctrl)
780{
781	if (pciehp_request_irq(ctrl))
782		return -1;
783	pcie_enable_notification(ctrl);
784	ctrl->notification_enabled = 1;
785	return 0;
786}
787
788void pcie_shutdown_notification(struct controller *ctrl)
789{
790	if (ctrl->notification_enabled) {
791		pcie_disable_notification(ctrl);
792		pciehp_free_irq(ctrl);
793		ctrl->notification_enabled = 0;
794	}
795}
796
797static inline void dbg_ctrl(struct controller *ctrl)
798{
799	struct pci_dev *pdev = ctrl->pcie->port;
800	u16 reg16;
801
802	ctrl_dbg(ctrl, "Slot Capabilities      : 0x%08x\n", ctrl->slot_cap);
803	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &reg16);
804	ctrl_dbg(ctrl, "Slot Status            : 0x%04x\n", reg16);
805	pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &reg16);
806	ctrl_dbg(ctrl, "Slot Control           : 0x%04x\n", reg16);
807}
808
809#define FLAG(x, y)	(((x) & (y)) ? '+' : '-')
810
811struct controller *pcie_init(struct pcie_device *dev)
812{
813	struct controller *ctrl;
814	u32 slot_cap, link_cap;
815	u8 poweron;
816	struct pci_dev *pdev = dev->port;
817	struct pci_bus *subordinate = pdev->subordinate;
818
819	ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
820	if (!ctrl)
821		return NULL;
822
823	ctrl->pcie = dev;
824	pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, &slot_cap);
825
826	if (pdev->hotplug_user_indicators)
827		slot_cap &= ~(PCI_EXP_SLTCAP_AIP | PCI_EXP_SLTCAP_PIP);
828
829	/*
830	 * We assume no Thunderbolt controllers support Command Complete events,
831	 * but some controllers falsely claim they do.
832	 */
833	if (pdev->is_thunderbolt)
834		slot_cap |= PCI_EXP_SLTCAP_NCCS;
835
836	ctrl->slot_cap = slot_cap;
837	mutex_init(&ctrl->ctrl_lock);
838	mutex_init(&ctrl->state_lock);
839	init_rwsem(&ctrl->reset_lock);
840	init_waitqueue_head(&ctrl->requester);
841	init_waitqueue_head(&ctrl->queue);
842	INIT_DELAYED_WORK(&ctrl->button_work, pciehp_queue_pushbutton_work);
843	dbg_ctrl(ctrl);
844
845	down_read(&pci_bus_sem);
846	ctrl->state = list_empty(&subordinate->devices) ? OFF_STATE : ON_STATE;
847	up_read(&pci_bus_sem);
848
 
 
 
 
 
 
 
 
 
 
849	/* Check if Data Link Layer Link Active Reporting is implemented */
850	pcie_capability_read_dword(pdev, PCI_EXP_LNKCAP, &link_cap);
851
852	/* Clear all remaining event bits in Slot Status register. */
853	pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
854		PCI_EXP_SLTSTA_ABP | PCI_EXP_SLTSTA_PFD |
855		PCI_EXP_SLTSTA_MRLSC | PCI_EXP_SLTSTA_CC |
856		PCI_EXP_SLTSTA_DLLSC | PCI_EXP_SLTSTA_PDC);
857
858	ctrl_info(ctrl, "Slot #%d AttnBtn%c PwrCtrl%c MRL%c AttnInd%c PwrInd%c HotPlug%c Surprise%c Interlock%c NoCompl%c LLActRep%c%s\n",
859		(slot_cap & PCI_EXP_SLTCAP_PSN) >> 19,
860		FLAG(slot_cap, PCI_EXP_SLTCAP_ABP),
861		FLAG(slot_cap, PCI_EXP_SLTCAP_PCP),
862		FLAG(slot_cap, PCI_EXP_SLTCAP_MRLSP),
863		FLAG(slot_cap, PCI_EXP_SLTCAP_AIP),
864		FLAG(slot_cap, PCI_EXP_SLTCAP_PIP),
865		FLAG(slot_cap, PCI_EXP_SLTCAP_HPC),
866		FLAG(slot_cap, PCI_EXP_SLTCAP_HPS),
867		FLAG(slot_cap, PCI_EXP_SLTCAP_EIP),
868		FLAG(slot_cap, PCI_EXP_SLTCAP_NCCS),
 
869		FLAG(link_cap, PCI_EXP_LNKCAP_DLLLARC),
870		pdev->broken_cmd_compl ? " (with Cmd Compl erratum)" : "");
871
872	/*
873	 * If empty slot's power status is on, turn power off.  The IRQ isn't
874	 * requested yet, so avoid triggering a notification with this command.
875	 */
876	if (POWER_CTRL(ctrl)) {
877		pciehp_get_power_status(ctrl, &poweron);
878		if (!pciehp_card_present_or_link_active(ctrl) && poweron) {
879			pcie_disable_notification(ctrl);
880			pciehp_power_off_slot(ctrl);
881		}
882	}
883
884	return ctrl;
885}
886
887void pciehp_release_ctrl(struct controller *ctrl)
888{
889	cancel_delayed_work_sync(&ctrl->button_work);
890	kfree(ctrl);
891}
892
893static void quirk_cmd_compl(struct pci_dev *pdev)
894{
895	u32 slot_cap;
896
897	if (pci_is_pcie(pdev)) {
898		pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, &slot_cap);
899		if (slot_cap & PCI_EXP_SLTCAP_HPC &&
900		    !(slot_cap & PCI_EXP_SLTCAP_NCCS))
901			pdev->broken_cmd_compl = 1;
902	}
903}
904DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_VENDOR_ID_INTEL, PCI_ANY_ID,
905			      PCI_CLASS_BRIDGE_PCI, 8, quirk_cmd_compl);
906DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_VENDOR_ID_QCOM, 0x0400,
907			      PCI_CLASS_BRIDGE_PCI, 8, quirk_cmd_compl);
908DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_VENDOR_ID_QCOM, 0x0401,
909			      PCI_CLASS_BRIDGE_PCI, 8, quirk_cmd_compl);
910DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_VENDOR_ID_HXT, 0x0401,
911			      PCI_CLASS_BRIDGE_PCI, 8, quirk_cmd_compl);
v5.9
   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
  30static 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
  48static inline struct pci_dev *ctrl_dev(struct controller *ctrl)
  49{
  50	return ctrl->pcie->port;
  51}
  52
  53static irqreturn_t pciehp_isr(int irq, void *dev_id);
  54static irqreturn_t pciehp_ist(int irq, void *dev_id);
  55static int pciehp_poll(void *data);
  56
  57static 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
  77static 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
  85static 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
 109static 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
 154static 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
 200out:
 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 */
 210static 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 */
 216static 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 */
 232int 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
 248static 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
 274static 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	pci_info(pdev, "Timeout waiting for Presence Detect\n");
 288}
 289
 290int 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		return -1;
 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_err(ctrl, "link training error: status %#06x\n",
 315			 lnk_status);
 316		return -1;
 317	}
 318
 319	pcie_update_link_speed(ctrl->pcie->port->subordinate, lnk_status);
 320
 321	if (!found)
 322		return -1;
 323
 324	return 0;
 325}
 326
 327static int __pciehp_link_set(struct controller *ctrl, bool enable)
 328{
 329	struct pci_dev *pdev = ctrl_dev(ctrl);
 330	u16 lnk_ctrl;
 331
 332	pcie_capability_read_word(pdev, PCI_EXP_LNKCTL, &lnk_ctrl);
 333
 334	if (enable)
 335		lnk_ctrl &= ~PCI_EXP_LNKCTL_LD;
 336	else
 337		lnk_ctrl |= PCI_EXP_LNKCTL_LD;
 338
 339	pcie_capability_write_word(pdev, PCI_EXP_LNKCTL, lnk_ctrl);
 340	ctrl_dbg(ctrl, "%s: lnk_ctrl = %x\n", __func__, lnk_ctrl);
 341	return 0;
 342}
 343
 344static int pciehp_link_enable(struct controller *ctrl)
 345{
 346	return __pciehp_link_set(ctrl, true);
 347}
 348
 349int pciehp_get_raw_indicator_status(struct hotplug_slot *hotplug_slot,
 350				    u8 *status)
 351{
 352	struct controller *ctrl = to_ctrl(hotplug_slot);
 353	struct pci_dev *pdev = ctrl_dev(ctrl);
 354	u16 slot_ctrl;
 355
 356	pci_config_pm_runtime_get(pdev);
 357	pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &slot_ctrl);
 358	pci_config_pm_runtime_put(pdev);
 359	*status = (slot_ctrl & (PCI_EXP_SLTCTL_AIC | PCI_EXP_SLTCTL_PIC)) >> 6;
 360	return 0;
 361}
 362
 363int pciehp_get_attention_status(struct hotplug_slot *hotplug_slot, u8 *status)
 364{
 365	struct controller *ctrl = to_ctrl(hotplug_slot);
 366	struct pci_dev *pdev = ctrl_dev(ctrl);
 367	u16 slot_ctrl;
 368
 369	pci_config_pm_runtime_get(pdev);
 370	pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &slot_ctrl);
 371	pci_config_pm_runtime_put(pdev);
 372	ctrl_dbg(ctrl, "%s: SLOTCTRL %x, value read %x\n", __func__,
 373		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_ctrl);
 374
 375	switch (slot_ctrl & PCI_EXP_SLTCTL_AIC) {
 376	case PCI_EXP_SLTCTL_ATTN_IND_ON:
 377		*status = 1;	/* On */
 378		break;
 379	case PCI_EXP_SLTCTL_ATTN_IND_BLINK:
 380		*status = 2;	/* Blink */
 381		break;
 382	case PCI_EXP_SLTCTL_ATTN_IND_OFF:
 383		*status = 0;	/* Off */
 384		break;
 385	default:
 386		*status = 0xFF;
 387		break;
 388	}
 389
 390	return 0;
 391}
 392
 393void pciehp_get_power_status(struct controller *ctrl, u8 *status)
 394{
 395	struct pci_dev *pdev = ctrl_dev(ctrl);
 396	u16 slot_ctrl;
 397
 398	pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &slot_ctrl);
 399	ctrl_dbg(ctrl, "%s: SLOTCTRL %x value read %x\n", __func__,
 400		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_ctrl);
 401
 402	switch (slot_ctrl & PCI_EXP_SLTCTL_PCC) {
 403	case PCI_EXP_SLTCTL_PWR_ON:
 404		*status = 1;	/* On */
 405		break;
 406	case PCI_EXP_SLTCTL_PWR_OFF:
 407		*status = 0;	/* Off */
 408		break;
 409	default:
 410		*status = 0xFF;
 411		break;
 412	}
 413}
 414
 415void pciehp_get_latch_status(struct controller *ctrl, u8 *status)
 416{
 417	struct pci_dev *pdev = ctrl_dev(ctrl);
 418	u16 slot_status;
 419
 420	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
 421	*status = !!(slot_status & PCI_EXP_SLTSTA_MRLSS);
 422}
 423
 424/**
 425 * pciehp_card_present() - Is the card present
 426 * @ctrl: PCIe hotplug controller
 427 *
 428 * Function checks whether the card is currently present in the slot and
 429 * in that case returns true. Note it is possible that the card is
 430 * removed immediately after the check so the caller may need to take
 431 * this into account.
 432 *
 433 * It the hotplug controller itself is not available anymore returns
 434 * %-ENODEV.
 435 */
 436int pciehp_card_present(struct controller *ctrl)
 437{
 438	struct pci_dev *pdev = ctrl_dev(ctrl);
 439	u16 slot_status;
 440	int ret;
 441
 442	ret = pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
 443	if (ret == PCIBIOS_DEVICE_NOT_FOUND || slot_status == (u16)~0)
 444		return -ENODEV;
 445
 446	return !!(slot_status & PCI_EXP_SLTSTA_PDS);
 447}
 448
 449/**
 450 * pciehp_card_present_or_link_active() - whether given slot is occupied
 451 * @ctrl: PCIe hotplug controller
 452 *
 453 * Unlike pciehp_card_present(), which determines presence solely from the
 454 * Presence Detect State bit, this helper also returns true if the Link Active
 455 * bit is set.  This is a concession to broken hotplug ports which hardwire
 456 * Presence Detect State to zero, such as Wilocity's [1ae9:0200].
 457 *
 458 * Returns: %1 if the slot is occupied and %0 if it is not. If the hotplug
 459 *	    port is not present anymore returns %-ENODEV.
 460 */
 461int pciehp_card_present_or_link_active(struct controller *ctrl)
 462{
 463	int ret;
 464
 465	ret = pciehp_card_present(ctrl);
 466	if (ret)
 467		return ret;
 468
 469	return pciehp_check_link_active(ctrl);
 470}
 471
 472int pciehp_query_power_fault(struct controller *ctrl)
 473{
 474	struct pci_dev *pdev = ctrl_dev(ctrl);
 475	u16 slot_status;
 476
 477	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
 478	return !!(slot_status & PCI_EXP_SLTSTA_PFD);
 479}
 480
 481int pciehp_set_raw_indicator_status(struct hotplug_slot *hotplug_slot,
 482				    u8 status)
 483{
 484	struct controller *ctrl = to_ctrl(hotplug_slot);
 485	struct pci_dev *pdev = ctrl_dev(ctrl);
 486
 487	pci_config_pm_runtime_get(pdev);
 488	pcie_write_cmd_nowait(ctrl, status << 6,
 489			      PCI_EXP_SLTCTL_AIC | PCI_EXP_SLTCTL_PIC);
 490	pci_config_pm_runtime_put(pdev);
 491	return 0;
 492}
 493
 494/**
 495 * pciehp_set_indicators() - set attention indicator, power indicator, or both
 496 * @ctrl: PCIe hotplug controller
 497 * @pwr: one of:
 498 *	PCI_EXP_SLTCTL_PWR_IND_ON
 499 *	PCI_EXP_SLTCTL_PWR_IND_BLINK
 500 *	PCI_EXP_SLTCTL_PWR_IND_OFF
 501 * @attn: one of:
 502 *	PCI_EXP_SLTCTL_ATTN_IND_ON
 503 *	PCI_EXP_SLTCTL_ATTN_IND_BLINK
 504 *	PCI_EXP_SLTCTL_ATTN_IND_OFF
 505 *
 506 * Either @pwr or @attn can also be INDICATOR_NOOP to leave that indicator
 507 * unchanged.
 508 */
 509void pciehp_set_indicators(struct controller *ctrl, int pwr, int attn)
 510{
 511	u16 cmd = 0, mask = 0;
 512
 513	if (PWR_LED(ctrl) && pwr != INDICATOR_NOOP) {
 514		cmd |= (pwr & PCI_EXP_SLTCTL_PIC);
 515		mask |= PCI_EXP_SLTCTL_PIC;
 516	}
 517
 518	if (ATTN_LED(ctrl) && attn != INDICATOR_NOOP) {
 519		cmd |= (attn & PCI_EXP_SLTCTL_AIC);
 520		mask |= PCI_EXP_SLTCTL_AIC;
 521	}
 522
 523	if (cmd) {
 524		pcie_write_cmd_nowait(ctrl, cmd, mask);
 525		ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
 526			 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, cmd);
 527	}
 528}
 529
 530int pciehp_power_on_slot(struct controller *ctrl)
 531{
 532	struct pci_dev *pdev = ctrl_dev(ctrl);
 533	u16 slot_status;
 534	int retval;
 535
 536	/* Clear power-fault bit from previous power failures */
 537	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
 538	if (slot_status & PCI_EXP_SLTSTA_PFD)
 539		pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
 540					   PCI_EXP_SLTSTA_PFD);
 541	ctrl->power_fault_detected = 0;
 542
 543	pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_PWR_ON, PCI_EXP_SLTCTL_PCC);
 544	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
 545		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL,
 546		 PCI_EXP_SLTCTL_PWR_ON);
 547
 548	retval = pciehp_link_enable(ctrl);
 549	if (retval)
 550		ctrl_err(ctrl, "%s: Can not enable the link!\n", __func__);
 551
 552	return retval;
 553}
 554
 555void pciehp_power_off_slot(struct controller *ctrl)
 556{
 557	pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_PWR_OFF, PCI_EXP_SLTCTL_PCC);
 558	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
 559		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL,
 560		 PCI_EXP_SLTCTL_PWR_OFF);
 561}
 562
 563static irqreturn_t pciehp_isr(int irq, void *dev_id)
 564{
 565	struct controller *ctrl = (struct controller *)dev_id;
 566	struct pci_dev *pdev = ctrl_dev(ctrl);
 567	struct device *parent = pdev->dev.parent;
 568	u16 status, events = 0;
 569
 570	/*
 571	 * Interrupts only occur in D3hot or shallower and only if enabled
 572	 * in the Slot Control register (PCIe r4.0, sec 6.7.3.4).
 573	 */
 574	if (pdev->current_state == PCI_D3cold ||
 575	    (!(ctrl->slot_ctrl & PCI_EXP_SLTCTL_HPIE) && !pciehp_poll_mode))
 576		return IRQ_NONE;
 577
 578	/*
 579	 * Keep the port accessible by holding a runtime PM ref on its parent.
 580	 * Defer resume of the parent to the IRQ thread if it's suspended.
 581	 * Mask the interrupt until then.
 582	 */
 583	if (parent) {
 584		pm_runtime_get_noresume(parent);
 585		if (!pm_runtime_active(parent)) {
 586			pm_runtime_put(parent);
 587			disable_irq_nosync(irq);
 588			atomic_or(RERUN_ISR, &ctrl->pending_events);
 589			return IRQ_WAKE_THREAD;
 590		}
 591	}
 592
 593read_status:
 594	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &status);
 595	if (status == (u16) ~0) {
 596		ctrl_info(ctrl, "%s: no response from device\n", __func__);
 597		if (parent)
 598			pm_runtime_put(parent);
 599		return IRQ_NONE;
 600	}
 601
 602	/*
 603	 * Slot Status contains plain status bits as well as event
 604	 * notification bits; right now we only want the event bits.
 605	 */
 606	status &= PCI_EXP_SLTSTA_ABP | PCI_EXP_SLTSTA_PFD |
 607		  PCI_EXP_SLTSTA_PDC | PCI_EXP_SLTSTA_CC |
 608		  PCI_EXP_SLTSTA_DLLSC;
 609
 610	/*
 611	 * If we've already reported a power fault, don't report it again
 612	 * until we've done something to handle it.
 613	 */
 614	if (ctrl->power_fault_detected)
 615		status &= ~PCI_EXP_SLTSTA_PFD;
 616
 617	events |= status;
 618	if (!events) {
 619		if (parent)
 620			pm_runtime_put(parent);
 621		return IRQ_NONE;
 622	}
 623
 624	if (status) {
 625		pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, events);
 626
 627		/*
 628		 * In MSI mode, all event bits must be zero before the port
 629		 * will send a new interrupt (PCIe Base Spec r5.0 sec 6.7.3.4).
 630		 * So re-read the Slot Status register in case a bit was set
 631		 * between read and write.
 632		 */
 633		if (pci_dev_msi_enabled(pdev) && !pciehp_poll_mode)
 634			goto read_status;
 635	}
 636
 637	ctrl_dbg(ctrl, "pending interrupts %#06x from Slot Status\n", events);
 638	if (parent)
 639		pm_runtime_put(parent);
 640
 641	/*
 642	 * Command Completed notifications are not deferred to the
 643	 * IRQ thread because it may be waiting for their arrival.
 644	 */
 645	if (events & PCI_EXP_SLTSTA_CC) {
 646		ctrl->cmd_busy = 0;
 647		smp_mb();
 648		wake_up(&ctrl->queue);
 649
 650		if (events == PCI_EXP_SLTSTA_CC)
 651			return IRQ_HANDLED;
 652
 653		events &= ~PCI_EXP_SLTSTA_CC;
 654	}
 655
 656	if (pdev->ignore_hotplug) {
 657		ctrl_dbg(ctrl, "ignoring hotplug event %#06x\n", events);
 658		return IRQ_HANDLED;
 659	}
 660
 661	/* Save pending events for consumption by IRQ thread. */
 662	atomic_or(events, &ctrl->pending_events);
 663	return IRQ_WAKE_THREAD;
 664}
 665
 666static irqreturn_t pciehp_ist(int irq, void *dev_id)
 667{
 668	struct controller *ctrl = (struct controller *)dev_id;
 669	struct pci_dev *pdev = ctrl_dev(ctrl);
 670	irqreturn_t ret;
 671	u32 events;
 672
 673	ctrl->ist_running = true;
 674	pci_config_pm_runtime_get(pdev);
 675
 676	/* rerun pciehp_isr() if the port was inaccessible on interrupt */
 677	if (atomic_fetch_and(~RERUN_ISR, &ctrl->pending_events) & RERUN_ISR) {
 678		ret = pciehp_isr(irq, dev_id);
 679		enable_irq(irq);
 680		if (ret != IRQ_WAKE_THREAD)
 681			goto out;
 
 
 682	}
 683
 684	synchronize_hardirq(irq);
 685	events = atomic_xchg(&ctrl->pending_events, 0);
 686	if (!events) {
 687		ret = IRQ_NONE;
 688		goto out;
 689	}
 690
 691	/* Check Attention Button Pressed */
 692	if (events & PCI_EXP_SLTSTA_ABP) {
 693		ctrl_info(ctrl, "Slot(%s): Attention button pressed\n",
 694			  slot_name(ctrl));
 695		pciehp_handle_button_press(ctrl);
 696	}
 697
 698	/* Check Power Fault Detected */
 699	if ((events & PCI_EXP_SLTSTA_PFD) && !ctrl->power_fault_detected) {
 700		ctrl->power_fault_detected = 1;
 701		ctrl_err(ctrl, "Slot(%s): Power fault\n", slot_name(ctrl));
 702		pciehp_set_indicators(ctrl, PCI_EXP_SLTCTL_PWR_IND_OFF,
 703				      PCI_EXP_SLTCTL_ATTN_IND_ON);
 704	}
 705
 706	/*
 707	 * Disable requests have higher priority than Presence Detect Changed
 708	 * or Data Link Layer State Changed events.
 709	 */
 710	down_read(&ctrl->reset_lock);
 711	if (events & DISABLE_SLOT)
 712		pciehp_handle_disable_request(ctrl);
 713	else if (events & (PCI_EXP_SLTSTA_PDC | PCI_EXP_SLTSTA_DLLSC))
 714		pciehp_handle_presence_or_link_change(ctrl, events);
 715	up_read(&ctrl->reset_lock);
 716
 717	ret = IRQ_HANDLED;
 718out:
 719	pci_config_pm_runtime_put(pdev);
 720	ctrl->ist_running = false;
 721	wake_up(&ctrl->requester);
 722	return ret;
 723}
 724
 725static int pciehp_poll(void *data)
 726{
 727	struct controller *ctrl = data;
 728
 729	schedule_timeout_idle(10 * HZ); /* start with 10 sec delay */
 730
 731	while (!kthread_should_stop()) {
 732		/* poll for interrupt events or user requests */
 733		while (pciehp_isr(IRQ_NOTCONNECTED, ctrl) == IRQ_WAKE_THREAD ||
 734		       atomic_read(&ctrl->pending_events))
 735			pciehp_ist(IRQ_NOTCONNECTED, ctrl);
 736
 737		if (pciehp_poll_time <= 0 || pciehp_poll_time > 60)
 738			pciehp_poll_time = 2; /* clamp to sane value */
 739
 740		schedule_timeout_idle(pciehp_poll_time * HZ);
 741	}
 742
 743	return 0;
 744}
 745
 746static void pcie_enable_notification(struct controller *ctrl)
 747{
 748	u16 cmd, mask;
 749
 750	/*
 751	 * TBD: Power fault detected software notification support.
 752	 *
 753	 * Power fault detected software notification is not enabled
 754	 * now, because it caused power fault detected interrupt storm
 755	 * on some machines. On those machines, power fault detected
 756	 * bit in the slot status register was set again immediately
 757	 * when it is cleared in the interrupt service routine, and
 758	 * next power fault detected interrupt was notified again.
 759	 */
 760
 761	/*
 762	 * Always enable link events: thus link-up and link-down shall
 763	 * always be treated as hotplug and unplug respectively. Enable
 764	 * presence detect only if Attention Button is not present.
 765	 */
 766	cmd = PCI_EXP_SLTCTL_DLLSCE;
 767	if (ATTN_BUTTN(ctrl))
 768		cmd |= PCI_EXP_SLTCTL_ABPE;
 769	else
 770		cmd |= PCI_EXP_SLTCTL_PDCE;
 771	if (!pciehp_poll_mode)
 772		cmd |= PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE;
 773
 774	mask = (PCI_EXP_SLTCTL_PDCE | PCI_EXP_SLTCTL_ABPE |
 775		PCI_EXP_SLTCTL_PFDE |
 776		PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE |
 777		PCI_EXP_SLTCTL_DLLSCE);
 778
 779	pcie_write_cmd_nowait(ctrl, cmd, mask);
 780	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
 781		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, cmd);
 782}
 783
 784static void pcie_disable_notification(struct controller *ctrl)
 785{
 786	u16 mask;
 787
 788	mask = (PCI_EXP_SLTCTL_PDCE | PCI_EXP_SLTCTL_ABPE |
 789		PCI_EXP_SLTCTL_MRLSCE | PCI_EXP_SLTCTL_PFDE |
 790		PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE |
 791		PCI_EXP_SLTCTL_DLLSCE);
 792	pcie_write_cmd(ctrl, 0, mask);
 793	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
 794		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, 0);
 795}
 796
 797void pcie_clear_hotplug_events(struct controller *ctrl)
 798{
 799	pcie_capability_write_word(ctrl_dev(ctrl), PCI_EXP_SLTSTA,
 800				   PCI_EXP_SLTSTA_PDC | PCI_EXP_SLTSTA_DLLSC);
 801}
 802
 803void pcie_enable_interrupt(struct controller *ctrl)
 804{
 805	u16 mask;
 806
 807	mask = PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_DLLSCE;
 808	pcie_write_cmd(ctrl, mask, mask);
 809}
 810
 811void pcie_disable_interrupt(struct controller *ctrl)
 812{
 813	u16 mask;
 814
 815	/*
 816	 * Mask hot-plug interrupt to prevent it triggering immediately
 817	 * when the link goes inactive (we still get PME when any of the
 818	 * enabled events is detected). Same goes with Link Layer State
 819	 * changed event which generates PME immediately when the link goes
 820	 * inactive so mask it as well.
 821	 */
 822	mask = PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_DLLSCE;
 823	pcie_write_cmd(ctrl, 0, mask);
 824}
 825
 826/*
 827 * pciehp has a 1:1 bus:slot relationship so we ultimately want a secondary
 828 * bus reset of the bridge, but at the same time we want to ensure that it is
 829 * not seen as a hot-unplug, followed by the hot-plug of the device. Thus,
 830 * disable link state notification and presence detection change notification
 831 * momentarily, if we see that they could interfere. Also, clear any spurious
 832 * events after.
 833 */
 834int pciehp_reset_slot(struct hotplug_slot *hotplug_slot, int probe)
 835{
 836	struct controller *ctrl = to_ctrl(hotplug_slot);
 837	struct pci_dev *pdev = ctrl_dev(ctrl);
 838	u16 stat_mask = 0, ctrl_mask = 0;
 839	int rc;
 840
 841	if (probe)
 842		return 0;
 843
 844	down_write(&ctrl->reset_lock);
 845
 846	if (!ATTN_BUTTN(ctrl)) {
 847		ctrl_mask |= PCI_EXP_SLTCTL_PDCE;
 848		stat_mask |= PCI_EXP_SLTSTA_PDC;
 849	}
 850	ctrl_mask |= PCI_EXP_SLTCTL_DLLSCE;
 851	stat_mask |= PCI_EXP_SLTSTA_DLLSC;
 852
 853	pcie_write_cmd(ctrl, 0, ctrl_mask);
 854	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
 855		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, 0);
 856
 857	rc = pci_bridge_secondary_bus_reset(ctrl->pcie->port);
 858
 859	pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, stat_mask);
 860	pcie_write_cmd_nowait(ctrl, ctrl_mask, ctrl_mask);
 861	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
 862		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, ctrl_mask);
 863
 864	up_write(&ctrl->reset_lock);
 865	return rc;
 866}
 867
 868int pcie_init_notification(struct controller *ctrl)
 869{
 870	if (pciehp_request_irq(ctrl))
 871		return -1;
 872	pcie_enable_notification(ctrl);
 873	ctrl->notification_enabled = 1;
 874	return 0;
 875}
 876
 877void pcie_shutdown_notification(struct controller *ctrl)
 878{
 879	if (ctrl->notification_enabled) {
 880		pcie_disable_notification(ctrl);
 881		pciehp_free_irq(ctrl);
 882		ctrl->notification_enabled = 0;
 883	}
 884}
 885
 886static inline void dbg_ctrl(struct controller *ctrl)
 887{
 888	struct pci_dev *pdev = ctrl->pcie->port;
 889	u16 reg16;
 890
 891	ctrl_dbg(ctrl, "Slot Capabilities      : 0x%08x\n", ctrl->slot_cap);
 892	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &reg16);
 893	ctrl_dbg(ctrl, "Slot Status            : 0x%04x\n", reg16);
 894	pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &reg16);
 895	ctrl_dbg(ctrl, "Slot Control           : 0x%04x\n", reg16);
 896}
 897
 898#define FLAG(x, y)	(((x) & (y)) ? '+' : '-')
 899
 900struct controller *pcie_init(struct pcie_device *dev)
 901{
 902	struct controller *ctrl;
 903	u32 slot_cap, slot_cap2, link_cap;
 904	u8 poweron;
 905	struct pci_dev *pdev = dev->port;
 906	struct pci_bus *subordinate = pdev->subordinate;
 907
 908	ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
 909	if (!ctrl)
 910		return NULL;
 911
 912	ctrl->pcie = dev;
 913	pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, &slot_cap);
 914
 915	if (pdev->hotplug_user_indicators)
 916		slot_cap &= ~(PCI_EXP_SLTCAP_AIP | PCI_EXP_SLTCAP_PIP);
 917
 918	/*
 919	 * We assume no Thunderbolt controllers support Command Complete events,
 920	 * but some controllers falsely claim they do.
 921	 */
 922	if (pdev->is_thunderbolt)
 923		slot_cap |= PCI_EXP_SLTCAP_NCCS;
 924
 925	ctrl->slot_cap = slot_cap;
 926	mutex_init(&ctrl->ctrl_lock);
 927	mutex_init(&ctrl->state_lock);
 928	init_rwsem(&ctrl->reset_lock);
 929	init_waitqueue_head(&ctrl->requester);
 930	init_waitqueue_head(&ctrl->queue);
 931	INIT_DELAYED_WORK(&ctrl->button_work, pciehp_queue_pushbutton_work);
 932	dbg_ctrl(ctrl);
 933
 934	down_read(&pci_bus_sem);
 935	ctrl->state = list_empty(&subordinate->devices) ? OFF_STATE : ON_STATE;
 936	up_read(&pci_bus_sem);
 937
 938	pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP2, &slot_cap2);
 939	if (slot_cap2 & PCI_EXP_SLTCAP2_IBPD) {
 940		pcie_write_cmd_nowait(ctrl, PCI_EXP_SLTCTL_IBPD_DISABLE,
 941				      PCI_EXP_SLTCTL_IBPD_DISABLE);
 942		ctrl->inband_presence_disabled = 1;
 943	}
 944
 945	if (dmi_first_match(inband_presence_disabled_dmi_table))
 946		ctrl->inband_presence_disabled = 1;
 947
 948	/* Check if Data Link Layer Link Active Reporting is implemented */
 949	pcie_capability_read_dword(pdev, PCI_EXP_LNKCAP, &link_cap);
 950
 951	/* Clear all remaining event bits in Slot Status register. */
 952	pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
 953		PCI_EXP_SLTSTA_ABP | PCI_EXP_SLTSTA_PFD |
 954		PCI_EXP_SLTSTA_MRLSC | PCI_EXP_SLTSTA_CC |
 955		PCI_EXP_SLTSTA_DLLSC | PCI_EXP_SLTSTA_PDC);
 956
 957	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",
 958		(slot_cap & PCI_EXP_SLTCAP_PSN) >> 19,
 959		FLAG(slot_cap, PCI_EXP_SLTCAP_ABP),
 960		FLAG(slot_cap, PCI_EXP_SLTCAP_PCP),
 961		FLAG(slot_cap, PCI_EXP_SLTCAP_MRLSP),
 962		FLAG(slot_cap, PCI_EXP_SLTCAP_AIP),
 963		FLAG(slot_cap, PCI_EXP_SLTCAP_PIP),
 964		FLAG(slot_cap, PCI_EXP_SLTCAP_HPC),
 965		FLAG(slot_cap, PCI_EXP_SLTCAP_HPS),
 966		FLAG(slot_cap, PCI_EXP_SLTCAP_EIP),
 967		FLAG(slot_cap, PCI_EXP_SLTCAP_NCCS),
 968		FLAG(slot_cap2, PCI_EXP_SLTCAP2_IBPD),
 969		FLAG(link_cap, PCI_EXP_LNKCAP_DLLLARC),
 970		pdev->broken_cmd_compl ? " (with Cmd Compl erratum)" : "");
 971
 972	/*
 973	 * If empty slot's power status is on, turn power off.  The IRQ isn't
 974	 * requested yet, so avoid triggering a notification with this command.
 975	 */
 976	if (POWER_CTRL(ctrl)) {
 977		pciehp_get_power_status(ctrl, &poweron);
 978		if (!pciehp_card_present_or_link_active(ctrl) && poweron) {
 979			pcie_disable_notification(ctrl);
 980			pciehp_power_off_slot(ctrl);
 981		}
 982	}
 983
 984	return ctrl;
 985}
 986
 987void pciehp_release_ctrl(struct controller *ctrl)
 988{
 989	cancel_delayed_work_sync(&ctrl->button_work);
 990	kfree(ctrl);
 991}
 992
 993static void quirk_cmd_compl(struct pci_dev *pdev)
 994{
 995	u32 slot_cap;
 996
 997	if (pci_is_pcie(pdev)) {
 998		pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, &slot_cap);
 999		if (slot_cap & PCI_EXP_SLTCAP_HPC &&
1000		    !(slot_cap & PCI_EXP_SLTCAP_NCCS))
1001			pdev->broken_cmd_compl = 1;
1002	}
1003}
1004DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_VENDOR_ID_INTEL, PCI_ANY_ID,
1005			      PCI_CLASS_BRIDGE_PCI, 8, quirk_cmd_compl);
1006DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_VENDOR_ID_QCOM, 0x0400,
1007			      PCI_CLASS_BRIDGE_PCI, 8, quirk_cmd_compl);
1008DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_VENDOR_ID_QCOM, 0x0401,
1009			      PCI_CLASS_BRIDGE_PCI, 8, quirk_cmd_compl);
1010DECLARE_PCI_FIXUP_CLASS_EARLY(PCI_VENDOR_ID_HXT, 0x0401,
1011			      PCI_CLASS_BRIDGE_PCI, 8, quirk_cmd_compl);