xref: /openbmc/linux/drivers/pci/hotplug/pciehp_hpc.c (revision 84d517f3)
1 /*
2  * PCI Express PCI Hot Plug Driver
3  *
4  * Copyright (C) 1995,2001 Compaq Computer Corporation
5  * Copyright (C) 2001 Greg Kroah-Hartman (greg@kroah.com)
6  * Copyright (C) 2001 IBM Corp.
7  * Copyright (C) 2003-2004 Intel Corporation
8  *
9  * All rights reserved.
10  *
11  * This program is free software; you can redistribute it and/or modify
12  * it under the terms of the GNU General Public License as published by
13  * the Free Software Foundation; either version 2 of the License, or (at
14  * your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful, but
17  * WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
19  * NON INFRINGEMENT.  See the GNU General Public License for more
20  * details.
21  *
22  * You should have received a copy of the GNU General Public License
23  * along with this program; if not, write to the Free Software
24  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
25  *
26  * Send feedback to <greg@kroah.com>,<kristen.c.accardi@intel.com>
27  *
28  */
29 
30 #include <linux/kernel.h>
31 #include <linux/module.h>
32 #include <linux/types.h>
33 #include <linux/signal.h>
34 #include <linux/jiffies.h>
35 #include <linux/timer.h>
36 #include <linux/pci.h>
37 #include <linux/interrupt.h>
38 #include <linux/time.h>
39 #include <linux/slab.h>
40 
41 #include "../pci.h"
42 #include "pciehp.h"
43 
44 static inline struct pci_dev *ctrl_dev(struct controller *ctrl)
45 {
46 	return ctrl->pcie->port;
47 }
48 
49 static irqreturn_t pcie_isr(int irq, void *dev_id);
50 static void start_int_poll_timer(struct controller *ctrl, int sec);
51 
52 /* This is the interrupt polling timeout function. */
53 static void int_poll_timeout(unsigned long data)
54 {
55 	struct controller *ctrl = (struct controller *)data;
56 
57 	/* Poll for interrupt events.  regs == NULL => polling */
58 	pcie_isr(0, ctrl);
59 
60 	init_timer(&ctrl->poll_timer);
61 	if (!pciehp_poll_time)
62 		pciehp_poll_time = 2; /* default polling interval is 2 sec */
63 
64 	start_int_poll_timer(ctrl, pciehp_poll_time);
65 }
66 
67 /* This function starts the interrupt polling timer. */
68 static void start_int_poll_timer(struct controller *ctrl, int sec)
69 {
70 	/* Clamp to sane value */
71 	if ((sec <= 0) || (sec > 60))
72 		sec = 2;
73 
74 	ctrl->poll_timer.function = &int_poll_timeout;
75 	ctrl->poll_timer.data = (unsigned long)ctrl;
76 	ctrl->poll_timer.expires = jiffies + sec * HZ;
77 	add_timer(&ctrl->poll_timer);
78 }
79 
80 static inline int pciehp_request_irq(struct controller *ctrl)
81 {
82 	int retval, irq = ctrl->pcie->irq;
83 
84 	/* Install interrupt polling timer. Start with 10 sec delay */
85 	if (pciehp_poll_mode) {
86 		init_timer(&ctrl->poll_timer);
87 		start_int_poll_timer(ctrl, 10);
88 		return 0;
89 	}
90 
91 	/* Installs the interrupt handler */
92 	retval = request_irq(irq, pcie_isr, IRQF_SHARED, MY_NAME, ctrl);
93 	if (retval)
94 		ctrl_err(ctrl, "Cannot get irq %d for the hotplug controller\n",
95 			 irq);
96 	return retval;
97 }
98 
99 static inline void pciehp_free_irq(struct controller *ctrl)
100 {
101 	if (pciehp_poll_mode)
102 		del_timer_sync(&ctrl->poll_timer);
103 	else
104 		free_irq(ctrl->pcie->irq, ctrl);
105 }
106 
107 static int pcie_poll_cmd(struct controller *ctrl)
108 {
109 	struct pci_dev *pdev = ctrl_dev(ctrl);
110 	u16 slot_status;
111 	int timeout = 1000;
112 
113 	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
114 	if (slot_status & PCI_EXP_SLTSTA_CC) {
115 		pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
116 					   PCI_EXP_SLTSTA_CC);
117 		return 1;
118 	}
119 	while (timeout > 0) {
120 		msleep(10);
121 		timeout -= 10;
122 		pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
123 		if (slot_status & PCI_EXP_SLTSTA_CC) {
124 			pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
125 						   PCI_EXP_SLTSTA_CC);
126 			return 1;
127 		}
128 	}
129 	return 0;	/* timeout */
130 }
131 
132 static void pcie_wait_cmd(struct controller *ctrl, int poll)
133 {
134 	unsigned int msecs = pciehp_poll_mode ? 2500 : 1000;
135 	unsigned long timeout = msecs_to_jiffies(msecs);
136 	int rc;
137 
138 	if (poll)
139 		rc = pcie_poll_cmd(ctrl);
140 	else
141 		rc = wait_event_timeout(ctrl->queue, !ctrl->cmd_busy, timeout);
142 	if (!rc)
143 		ctrl_dbg(ctrl, "Command not completed in 1000 msec\n");
144 }
145 
146 /**
147  * pcie_write_cmd - Issue controller command
148  * @ctrl: controller to which the command is issued
149  * @cmd:  command value written to slot control register
150  * @mask: bitmask of slot control register to be modified
151  */
152 static void pcie_write_cmd(struct controller *ctrl, u16 cmd, u16 mask)
153 {
154 	struct pci_dev *pdev = ctrl_dev(ctrl);
155 	u16 slot_status;
156 	u16 slot_ctrl;
157 
158 	mutex_lock(&ctrl->ctrl_lock);
159 
160 	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
161 	if (slot_status & PCI_EXP_SLTSTA_CC) {
162 		pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
163 					   PCI_EXP_SLTSTA_CC);
164 		if (!ctrl->no_cmd_complete) {
165 			/*
166 			 * After 1 sec and CMD_COMPLETED still not set, just
167 			 * proceed forward to issue the next command according
168 			 * to spec. Just print out the error message.
169 			 */
170 			ctrl_dbg(ctrl, "CMD_COMPLETED not clear after 1 sec\n");
171 		} else if (!NO_CMD_CMPL(ctrl)) {
172 			/*
173 			 * This controller seems to notify of command completed
174 			 * event even though it supports none of power
175 			 * controller, attention led, power led and EMI.
176 			 */
177 			ctrl_dbg(ctrl, "Unexpected CMD_COMPLETED. Need to "
178 				 "wait for command completed event.\n");
179 			ctrl->no_cmd_complete = 0;
180 		} else {
181 			ctrl_dbg(ctrl, "Unexpected CMD_COMPLETED. Maybe "
182 				 "the controller is broken.\n");
183 		}
184 	}
185 
186 	pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &slot_ctrl);
187 	slot_ctrl &= ~mask;
188 	slot_ctrl |= (cmd & mask);
189 	ctrl->cmd_busy = 1;
190 	smp_mb();
191 	pcie_capability_write_word(pdev, PCI_EXP_SLTCTL, slot_ctrl);
192 
193 	/*
194 	 * Wait for command completion.
195 	 */
196 	if (!ctrl->no_cmd_complete) {
197 		int poll = 0;
198 		/*
199 		 * if hotplug interrupt is not enabled or command
200 		 * completed interrupt is not enabled, we need to poll
201 		 * command completed event.
202 		 */
203 		if (!(slot_ctrl & PCI_EXP_SLTCTL_HPIE) ||
204 		    !(slot_ctrl & PCI_EXP_SLTCTL_CCIE))
205 			poll = 1;
206                 pcie_wait_cmd(ctrl, poll);
207 	}
208 	mutex_unlock(&ctrl->ctrl_lock);
209 }
210 
211 bool pciehp_check_link_active(struct controller *ctrl)
212 {
213 	struct pci_dev *pdev = ctrl_dev(ctrl);
214 	u16 lnk_status;
215 	bool ret;
216 
217 	pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status);
218 	ret = !!(lnk_status & PCI_EXP_LNKSTA_DLLLA);
219 
220 	if (ret)
221 		ctrl_dbg(ctrl, "%s: lnk_status = %x\n", __func__, lnk_status);
222 
223 	return ret;
224 }
225 
226 static void __pcie_wait_link_active(struct controller *ctrl, bool active)
227 {
228 	int timeout = 1000;
229 
230 	if (pciehp_check_link_active(ctrl) == active)
231 		return;
232 	while (timeout > 0) {
233 		msleep(10);
234 		timeout -= 10;
235 		if (pciehp_check_link_active(ctrl) == active)
236 			return;
237 	}
238 	ctrl_dbg(ctrl, "Data Link Layer Link Active not %s in 1000 msec\n",
239 			active ? "set" : "cleared");
240 }
241 
242 static void pcie_wait_link_active(struct controller *ctrl)
243 {
244 	__pcie_wait_link_active(ctrl, true);
245 }
246 
247 static bool pci_bus_check_dev(struct pci_bus *bus, int devfn)
248 {
249 	u32 l;
250 	int count = 0;
251 	int delay = 1000, step = 20;
252 	bool found = false;
253 
254 	do {
255 		found = pci_bus_read_dev_vendor_id(bus, devfn, &l, 0);
256 		count++;
257 
258 		if (found)
259 			break;
260 
261 		msleep(step);
262 		delay -= step;
263 	} while (delay > 0);
264 
265 	if (count > 1 && pciehp_debug)
266 		printk(KERN_DEBUG "pci %04x:%02x:%02x.%d id reading try %d times with interval %d ms to get %08x\n",
267 			pci_domain_nr(bus), bus->number, PCI_SLOT(devfn),
268 			PCI_FUNC(devfn), count, step, l);
269 
270 	return found;
271 }
272 
273 int pciehp_check_link_status(struct controller *ctrl)
274 {
275 	struct pci_dev *pdev = ctrl_dev(ctrl);
276 	bool found;
277 	u16 lnk_status;
278 
279         /*
280          * Data Link Layer Link Active Reporting must be capable for
281          * hot-plug capable downstream port. But old controller might
282          * not implement it. In this case, we wait for 1000 ms.
283          */
284         if (ctrl->link_active_reporting)
285                 pcie_wait_link_active(ctrl);
286         else
287                 msleep(1000);
288 
289 	/* wait 100ms before read pci conf, and try in 1s */
290 	msleep(100);
291 	found = pci_bus_check_dev(ctrl->pcie->port->subordinate,
292 					PCI_DEVFN(0, 0));
293 
294 	pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status);
295 	ctrl_dbg(ctrl, "%s: lnk_status = %x\n", __func__, lnk_status);
296 	if ((lnk_status & PCI_EXP_LNKSTA_LT) ||
297 	    !(lnk_status & PCI_EXP_LNKSTA_NLW)) {
298 		ctrl_err(ctrl, "Link Training Error occurs \n");
299 		return -1;
300 	}
301 
302 	pcie_update_link_speed(ctrl->pcie->port->subordinate, lnk_status);
303 
304 	if (!found)
305 		return -1;
306 
307 	return 0;
308 }
309 
310 static int __pciehp_link_set(struct controller *ctrl, bool enable)
311 {
312 	struct pci_dev *pdev = ctrl_dev(ctrl);
313 	u16 lnk_ctrl;
314 
315 	pcie_capability_read_word(pdev, PCI_EXP_LNKCTL, &lnk_ctrl);
316 
317 	if (enable)
318 		lnk_ctrl &= ~PCI_EXP_LNKCTL_LD;
319 	else
320 		lnk_ctrl |= PCI_EXP_LNKCTL_LD;
321 
322 	pcie_capability_write_word(pdev, PCI_EXP_LNKCTL, lnk_ctrl);
323 	ctrl_dbg(ctrl, "%s: lnk_ctrl = %x\n", __func__, lnk_ctrl);
324 	return 0;
325 }
326 
327 static int pciehp_link_enable(struct controller *ctrl)
328 {
329 	return __pciehp_link_set(ctrl, true);
330 }
331 
332 void pciehp_get_attention_status(struct slot *slot, u8 *status)
333 {
334 	struct controller *ctrl = slot->ctrl;
335 	struct pci_dev *pdev = ctrl_dev(ctrl);
336 	u16 slot_ctrl;
337 
338 	pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &slot_ctrl);
339 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x, value read %x\n", __func__,
340 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_ctrl);
341 
342 	switch (slot_ctrl & PCI_EXP_SLTCTL_AIC) {
343 	case PCI_EXP_SLTCTL_ATTN_IND_ON:
344 		*status = 1;	/* On */
345 		break;
346 	case PCI_EXP_SLTCTL_ATTN_IND_BLINK:
347 		*status = 2;	/* Blink */
348 		break;
349 	case PCI_EXP_SLTCTL_ATTN_IND_OFF:
350 		*status = 0;	/* Off */
351 		break;
352 	default:
353 		*status = 0xFF;
354 		break;
355 	}
356 }
357 
358 void pciehp_get_power_status(struct slot *slot, u8 *status)
359 {
360 	struct controller *ctrl = slot->ctrl;
361 	struct pci_dev *pdev = ctrl_dev(ctrl);
362 	u16 slot_ctrl;
363 
364 	pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &slot_ctrl);
365 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x value read %x\n", __func__,
366 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_ctrl);
367 
368 	switch (slot_ctrl & PCI_EXP_SLTCTL_PCC) {
369 	case PCI_EXP_SLTCTL_PWR_ON:
370 		*status = 1;	/* On */
371 		break;
372 	case PCI_EXP_SLTCTL_PWR_OFF:
373 		*status = 0;	/* Off */
374 		break;
375 	default:
376 		*status = 0xFF;
377 		break;
378 	}
379 }
380 
381 void pciehp_get_latch_status(struct slot *slot, u8 *status)
382 {
383 	struct pci_dev *pdev = ctrl_dev(slot->ctrl);
384 	u16 slot_status;
385 
386 	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
387 	*status = !!(slot_status & PCI_EXP_SLTSTA_MRLSS);
388 }
389 
390 void pciehp_get_adapter_status(struct slot *slot, u8 *status)
391 {
392 	struct pci_dev *pdev = ctrl_dev(slot->ctrl);
393 	u16 slot_status;
394 
395 	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
396 	*status = !!(slot_status & PCI_EXP_SLTSTA_PDS);
397 }
398 
399 int pciehp_query_power_fault(struct slot *slot)
400 {
401 	struct pci_dev *pdev = ctrl_dev(slot->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 
408 void pciehp_set_attention_status(struct slot *slot, u8 value)
409 {
410 	struct controller *ctrl = slot->ctrl;
411 	u16 slot_cmd;
412 
413 	if (!ATTN_LED(ctrl))
414 		return;
415 
416 	switch (value) {
417 	case 0 :	/* turn off */
418 		slot_cmd = PCI_EXP_SLTCTL_ATTN_IND_OFF;
419 		break;
420 	case 1:		/* turn on */
421 		slot_cmd = PCI_EXP_SLTCTL_ATTN_IND_ON;
422 		break;
423 	case 2:		/* turn blink */
424 		slot_cmd = PCI_EXP_SLTCTL_ATTN_IND_BLINK;
425 		break;
426 	default:
427 		return;
428 	}
429 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
430 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL, slot_cmd);
431 	pcie_write_cmd(ctrl, slot_cmd, PCI_EXP_SLTCTL_AIC);
432 }
433 
434 void pciehp_green_led_on(struct slot *slot)
435 {
436 	struct controller *ctrl = slot->ctrl;
437 
438 	if (!PWR_LED(ctrl))
439 		return;
440 
441 	pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_PWR_IND_ON, PCI_EXP_SLTCTL_PIC);
442 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
443 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL,
444 		 PCI_EXP_SLTCTL_PWR_IND_ON);
445 }
446 
447 void pciehp_green_led_off(struct slot *slot)
448 {
449 	struct controller *ctrl = slot->ctrl;
450 
451 	if (!PWR_LED(ctrl))
452 		return;
453 
454 	pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_PWR_IND_OFF, PCI_EXP_SLTCTL_PIC);
455 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
456 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL,
457 		 PCI_EXP_SLTCTL_PWR_IND_OFF);
458 }
459 
460 void pciehp_green_led_blink(struct slot *slot)
461 {
462 	struct controller *ctrl = slot->ctrl;
463 
464 	if (!PWR_LED(ctrl))
465 		return;
466 
467 	pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_PWR_IND_BLINK, PCI_EXP_SLTCTL_PIC);
468 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
469 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL,
470 		 PCI_EXP_SLTCTL_PWR_IND_BLINK);
471 }
472 
473 int pciehp_power_on_slot(struct slot * slot)
474 {
475 	struct controller *ctrl = slot->ctrl;
476 	struct pci_dev *pdev = ctrl_dev(ctrl);
477 	u16 slot_status;
478 	int retval;
479 
480 	/* Clear sticky power-fault bit from previous power failures */
481 	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &slot_status);
482 	if (slot_status & PCI_EXP_SLTSTA_PFD)
483 		pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
484 					   PCI_EXP_SLTSTA_PFD);
485 	ctrl->power_fault_detected = 0;
486 
487 	pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_PWR_ON, PCI_EXP_SLTCTL_PCC);
488 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
489 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL,
490 		 PCI_EXP_SLTCTL_PWR_ON);
491 
492 	retval = pciehp_link_enable(ctrl);
493 	if (retval)
494 		ctrl_err(ctrl, "%s: Can not enable the link!\n", __func__);
495 
496 	return retval;
497 }
498 
499 void pciehp_power_off_slot(struct slot * slot)
500 {
501 	struct controller *ctrl = slot->ctrl;
502 
503 	pcie_write_cmd(ctrl, PCI_EXP_SLTCTL_PWR_OFF, PCI_EXP_SLTCTL_PCC);
504 	ctrl_dbg(ctrl, "%s: SLOTCTRL %x write cmd %x\n", __func__,
505 		 pci_pcie_cap(ctrl->pcie->port) + PCI_EXP_SLTCTL,
506 		 PCI_EXP_SLTCTL_PWR_OFF);
507 }
508 
509 static irqreturn_t pcie_isr(int irq, void *dev_id)
510 {
511 	struct controller *ctrl = (struct controller *)dev_id;
512 	struct pci_dev *pdev = ctrl_dev(ctrl);
513 	struct slot *slot = ctrl->slot;
514 	u16 detected, intr_loc;
515 
516 	/*
517 	 * In order to guarantee that all interrupt events are
518 	 * serviced, we need to re-inspect Slot Status register after
519 	 * clearing what is presumed to be the last pending interrupt.
520 	 */
521 	intr_loc = 0;
522 	do {
523 		pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &detected);
524 
525 		detected &= (PCI_EXP_SLTSTA_ABP | PCI_EXP_SLTSTA_PFD |
526 			     PCI_EXP_SLTSTA_MRLSC | PCI_EXP_SLTSTA_PDC |
527 			     PCI_EXP_SLTSTA_CC | PCI_EXP_SLTSTA_DLLSC);
528 		detected &= ~intr_loc;
529 		intr_loc |= detected;
530 		if (!intr_loc)
531 			return IRQ_NONE;
532 		if (detected)
533 			pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
534 						   intr_loc);
535 	} while (detected);
536 
537 	ctrl_dbg(ctrl, "%s: intr_loc %x\n", __func__, intr_loc);
538 
539 	/* Check Command Complete Interrupt Pending */
540 	if (intr_loc & PCI_EXP_SLTSTA_CC) {
541 		ctrl->cmd_busy = 0;
542 		smp_mb();
543 		wake_up(&ctrl->queue);
544 	}
545 
546 	if (!(intr_loc & ~PCI_EXP_SLTSTA_CC))
547 		return IRQ_HANDLED;
548 
549 	/* Check MRL Sensor Changed */
550 	if (intr_loc & PCI_EXP_SLTSTA_MRLSC)
551 		pciehp_handle_switch_change(slot);
552 
553 	/* Check Attention Button Pressed */
554 	if (intr_loc & PCI_EXP_SLTSTA_ABP)
555 		pciehp_handle_attention_button(slot);
556 
557 	/* Check Presence Detect Changed */
558 	if (intr_loc & PCI_EXP_SLTSTA_PDC)
559 		pciehp_handle_presence_change(slot);
560 
561 	/* Check Power Fault Detected */
562 	if ((intr_loc & PCI_EXP_SLTSTA_PFD) && !ctrl->power_fault_detected) {
563 		ctrl->power_fault_detected = 1;
564 		pciehp_handle_power_fault(slot);
565 	}
566 
567 	if (intr_loc & PCI_EXP_SLTSTA_DLLSC)
568 		pciehp_handle_linkstate_change(slot);
569 
570 	return IRQ_HANDLED;
571 }
572 
573 void pcie_enable_notification(struct controller *ctrl)
574 {
575 	u16 cmd, mask;
576 
577 	/*
578 	 * TBD: Power fault detected software notification support.
579 	 *
580 	 * Power fault detected software notification is not enabled
581 	 * now, because it caused power fault detected interrupt storm
582 	 * on some machines. On those machines, power fault detected
583 	 * bit in the slot status register was set again immediately
584 	 * when it is cleared in the interrupt service routine, and
585 	 * next power fault detected interrupt was notified again.
586 	 */
587 
588 	/*
589 	 * Always enable link events: thus link-up and link-down shall
590 	 * always be treated as hotplug and unplug respectively. Enable
591 	 * presence detect only if Attention Button is not present.
592 	 */
593 	cmd = PCI_EXP_SLTCTL_DLLSCE;
594 	if (ATTN_BUTTN(ctrl))
595 		cmd |= PCI_EXP_SLTCTL_ABPE;
596 	else
597 		cmd |= PCI_EXP_SLTCTL_PDCE;
598 	if (MRL_SENS(ctrl))
599 		cmd |= PCI_EXP_SLTCTL_MRLSCE;
600 	if (!pciehp_poll_mode)
601 		cmd |= PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE;
602 
603 	mask = (PCI_EXP_SLTCTL_PDCE | PCI_EXP_SLTCTL_ABPE |
604 		PCI_EXP_SLTCTL_MRLSCE | PCI_EXP_SLTCTL_PFDE |
605 		PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE |
606 		PCI_EXP_SLTCTL_DLLSCE);
607 
608 	pcie_write_cmd(ctrl, cmd, mask);
609 }
610 
611 static void pcie_disable_notification(struct controller *ctrl)
612 {
613 	u16 mask;
614 
615 	mask = (PCI_EXP_SLTCTL_PDCE | PCI_EXP_SLTCTL_ABPE |
616 		PCI_EXP_SLTCTL_MRLSCE | PCI_EXP_SLTCTL_PFDE |
617 		PCI_EXP_SLTCTL_HPIE | PCI_EXP_SLTCTL_CCIE |
618 		PCI_EXP_SLTCTL_DLLSCE);
619 	pcie_write_cmd(ctrl, 0, mask);
620 }
621 
622 /*
623  * pciehp has a 1:1 bus:slot relationship so we ultimately want a secondary
624  * bus reset of the bridge, but at the same time we want to ensure that it is
625  * not seen as a hot-unplug, followed by the hot-plug of the device. Thus,
626  * disable link state notification and presence detection change notification
627  * momentarily, if we see that they could interfere. Also, clear any spurious
628  * events after.
629  */
630 int pciehp_reset_slot(struct slot *slot, int probe)
631 {
632 	struct controller *ctrl = slot->ctrl;
633 	struct pci_dev *pdev = ctrl_dev(ctrl);
634 	u16 stat_mask = 0, ctrl_mask = 0;
635 
636 	if (probe)
637 		return 0;
638 
639 	if (!ATTN_BUTTN(ctrl)) {
640 		ctrl_mask |= PCI_EXP_SLTCTL_PDCE;
641 		stat_mask |= PCI_EXP_SLTSTA_PDC;
642 	}
643 	ctrl_mask |= PCI_EXP_SLTCTL_DLLSCE;
644 	stat_mask |= PCI_EXP_SLTSTA_DLLSC;
645 
646 	pcie_write_cmd(ctrl, 0, ctrl_mask);
647 	if (pciehp_poll_mode)
648 		del_timer_sync(&ctrl->poll_timer);
649 
650 	pci_reset_bridge_secondary_bus(ctrl->pcie->port);
651 
652 	pcie_capability_write_word(pdev, PCI_EXP_SLTSTA, stat_mask);
653 	pcie_write_cmd(ctrl, ctrl_mask, ctrl_mask);
654 	if (pciehp_poll_mode)
655 		int_poll_timeout(ctrl->poll_timer.data);
656 
657 	return 0;
658 }
659 
660 int pcie_init_notification(struct controller *ctrl)
661 {
662 	if (pciehp_request_irq(ctrl))
663 		return -1;
664 	pcie_enable_notification(ctrl);
665 	ctrl->notification_enabled = 1;
666 	return 0;
667 }
668 
669 static void pcie_shutdown_notification(struct controller *ctrl)
670 {
671 	if (ctrl->notification_enabled) {
672 		pcie_disable_notification(ctrl);
673 		pciehp_free_irq(ctrl);
674 		ctrl->notification_enabled = 0;
675 	}
676 }
677 
678 static int pcie_init_slot(struct controller *ctrl)
679 {
680 	struct slot *slot;
681 
682 	slot = kzalloc(sizeof(*slot), GFP_KERNEL);
683 	if (!slot)
684 		return -ENOMEM;
685 
686 	slot->wq = alloc_workqueue("pciehp-%u", 0, 0, PSN(ctrl));
687 	if (!slot->wq)
688 		goto abort;
689 
690 	slot->ctrl = ctrl;
691 	mutex_init(&slot->lock);
692 	mutex_init(&slot->hotplug_lock);
693 	INIT_DELAYED_WORK(&slot->work, pciehp_queue_pushbutton_work);
694 	ctrl->slot = slot;
695 	return 0;
696 abort:
697 	kfree(slot);
698 	return -ENOMEM;
699 }
700 
701 static void pcie_cleanup_slot(struct controller *ctrl)
702 {
703 	struct slot *slot = ctrl->slot;
704 	cancel_delayed_work(&slot->work);
705 	destroy_workqueue(slot->wq);
706 	kfree(slot);
707 }
708 
709 static inline void dbg_ctrl(struct controller *ctrl)
710 {
711 	int i;
712 	u16 reg16;
713 	struct pci_dev *pdev = ctrl->pcie->port;
714 
715 	if (!pciehp_debug)
716 		return;
717 
718 	ctrl_info(ctrl, "Hotplug Controller:\n");
719 	ctrl_info(ctrl, "  Seg/Bus/Dev/Func/IRQ : %s IRQ %d\n",
720 		  pci_name(pdev), pdev->irq);
721 	ctrl_info(ctrl, "  Vendor ID            : 0x%04x\n", pdev->vendor);
722 	ctrl_info(ctrl, "  Device ID            : 0x%04x\n", pdev->device);
723 	ctrl_info(ctrl, "  Subsystem ID         : 0x%04x\n",
724 		  pdev->subsystem_device);
725 	ctrl_info(ctrl, "  Subsystem Vendor ID  : 0x%04x\n",
726 		  pdev->subsystem_vendor);
727 	ctrl_info(ctrl, "  PCIe Cap offset      : 0x%02x\n",
728 		  pci_pcie_cap(pdev));
729 	for (i = 0; i < DEVICE_COUNT_RESOURCE; i++) {
730 		if (!pci_resource_len(pdev, i))
731 			continue;
732 		ctrl_info(ctrl, "  PCI resource [%d]     : %pR\n",
733 			  i, &pdev->resource[i]);
734 	}
735 	ctrl_info(ctrl, "Slot Capabilities      : 0x%08x\n", ctrl->slot_cap);
736 	ctrl_info(ctrl, "  Physical Slot Number : %d\n", PSN(ctrl));
737 	ctrl_info(ctrl, "  Attention Button     : %3s\n",
738 		  ATTN_BUTTN(ctrl) ? "yes" : "no");
739 	ctrl_info(ctrl, "  Power Controller     : %3s\n",
740 		  POWER_CTRL(ctrl) ? "yes" : "no");
741 	ctrl_info(ctrl, "  MRL Sensor           : %3s\n",
742 		  MRL_SENS(ctrl)   ? "yes" : "no");
743 	ctrl_info(ctrl, "  Attention Indicator  : %3s\n",
744 		  ATTN_LED(ctrl)   ? "yes" : "no");
745 	ctrl_info(ctrl, "  Power Indicator      : %3s\n",
746 		  PWR_LED(ctrl)    ? "yes" : "no");
747 	ctrl_info(ctrl, "  Hot-Plug Surprise    : %3s\n",
748 		  HP_SUPR_RM(ctrl) ? "yes" : "no");
749 	ctrl_info(ctrl, "  EMI Present          : %3s\n",
750 		  EMI(ctrl)        ? "yes" : "no");
751 	ctrl_info(ctrl, "  Command Completed    : %3s\n",
752 		  NO_CMD_CMPL(ctrl) ? "no" : "yes");
753 	pcie_capability_read_word(pdev, PCI_EXP_SLTSTA, &reg16);
754 	ctrl_info(ctrl, "Slot Status            : 0x%04x\n", reg16);
755 	pcie_capability_read_word(pdev, PCI_EXP_SLTCTL, &reg16);
756 	ctrl_info(ctrl, "Slot Control           : 0x%04x\n", reg16);
757 }
758 
759 #define FLAG(x,y)	(((x) & (y)) ? '+' : '-')
760 
761 struct controller *pcie_init(struct pcie_device *dev)
762 {
763 	struct controller *ctrl;
764 	u32 slot_cap, link_cap;
765 	struct pci_dev *pdev = dev->port;
766 
767 	ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
768 	if (!ctrl) {
769 		dev_err(&dev->device, "%s: Out of memory\n", __func__);
770 		goto abort;
771 	}
772 	ctrl->pcie = dev;
773 	pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP, &slot_cap);
774 	ctrl->slot_cap = slot_cap;
775 	mutex_init(&ctrl->ctrl_lock);
776 	init_waitqueue_head(&ctrl->queue);
777 	dbg_ctrl(ctrl);
778 	/*
779 	 * Controller doesn't notify of command completion if the "No
780 	 * Command Completed Support" bit is set in Slot Capability
781 	 * register or the controller supports none of power
782 	 * controller, attention led, power led and EMI.
783 	 */
784 	if (NO_CMD_CMPL(ctrl) ||
785 	    !(POWER_CTRL(ctrl) | ATTN_LED(ctrl) | PWR_LED(ctrl) | EMI(ctrl)))
786 	    ctrl->no_cmd_complete = 1;
787 
788         /* Check if Data Link Layer Link Active Reporting is implemented */
789         pcie_capability_read_dword(pdev, PCI_EXP_LNKCAP, &link_cap);
790         if (link_cap & PCI_EXP_LNKCAP_DLLLARC) {
791                 ctrl_dbg(ctrl, "Link Active Reporting supported\n");
792                 ctrl->link_active_reporting = 1;
793         }
794 
795 	/* Clear all remaining event bits in Slot Status register */
796 	pcie_capability_write_word(pdev, PCI_EXP_SLTSTA,
797 		PCI_EXP_SLTSTA_ABP | PCI_EXP_SLTSTA_PFD |
798 		PCI_EXP_SLTSTA_MRLSC | PCI_EXP_SLTSTA_PDC |
799 		PCI_EXP_SLTSTA_CC);
800 
801 	/* Disable software notification */
802 	pcie_disable_notification(ctrl);
803 
804 	ctrl_info(ctrl, "Slot #%d AttnBtn%c AttnInd%c PwrInd%c PwrCtrl%c MRL%c Interlock%c NoCompl%c LLActRep%c\n",
805 		(slot_cap & PCI_EXP_SLTCAP_PSN) >> 19,
806 		FLAG(slot_cap, PCI_EXP_SLTCAP_ABP),
807 		FLAG(slot_cap, PCI_EXP_SLTCAP_AIP),
808 		FLAG(slot_cap, PCI_EXP_SLTCAP_PIP),
809 		FLAG(slot_cap, PCI_EXP_SLTCAP_PCP),
810 		FLAG(slot_cap, PCI_EXP_SLTCAP_MRLSP),
811 		FLAG(slot_cap, PCI_EXP_SLTCAP_EIP),
812 		FLAG(slot_cap, PCI_EXP_SLTCAP_NCCS),
813 		FLAG(link_cap, PCI_EXP_LNKCAP_DLLLARC));
814 
815 	if (pcie_init_slot(ctrl))
816 		goto abort_ctrl;
817 
818 	return ctrl;
819 
820 abort_ctrl:
821 	kfree(ctrl);
822 abort:
823 	return NULL;
824 }
825 
826 void pciehp_release_ctrl(struct controller *ctrl)
827 {
828 	pcie_shutdown_notification(ctrl);
829 	pcie_cleanup_slot(ctrl);
830 	kfree(ctrl);
831 }
832