1 /*
2  * PCI Express Hot Plug Controller 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/module.h>
31 #include <linux/kernel.h>
32 #include <linux/types.h>
33 #include <linux/smp_lock.h>
34 #include <linux/pci.h>
35 #include <linux/workqueue.h>
36 #include "../pci.h"
37 #include "pciehp.h"
38 
39 static void interrupt_event_handler(struct work_struct *work);
40 
41 static int queue_interrupt_event(struct slot *p_slot, u32 event_type)
42 {
43 	struct event_info *info;
44 
45 	info = kmalloc(sizeof(*info), GFP_ATOMIC);
46 	if (!info)
47 		return -ENOMEM;
48 
49 	info->event_type = event_type;
50 	info->p_slot = p_slot;
51 	INIT_WORK(&info->work, interrupt_event_handler);
52 
53 	schedule_work(&info->work);
54 
55 	return 0;
56 }
57 
58 u8 pciehp_handle_attention_button(u8 hp_slot, struct controller *ctrl)
59 {
60 	struct slot *p_slot;
61 	u32 event_type;
62 
63 	/* Attention Button Change */
64 	dbg("pciehp:  Attention button interrupt received.\n");
65 
66 	p_slot = pciehp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
67 
68 	/*
69 	 *  Button pressed - See if need to TAKE ACTION!!!
70 	 */
71 	info("Button pressed on Slot(%s)\n", p_slot->name);
72 	event_type = INT_BUTTON_PRESS;
73 
74 	queue_interrupt_event(p_slot, event_type);
75 
76 	return 0;
77 }
78 
79 u8 pciehp_handle_switch_change(u8 hp_slot, struct controller *ctrl)
80 {
81 	struct slot *p_slot;
82 	u8 getstatus;
83 	u32 event_type;
84 
85 	/* Switch Change */
86 	dbg("pciehp:  Switch interrupt received.\n");
87 
88 	p_slot = pciehp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
89 	p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
90 
91 	if (getstatus) {
92 		/*
93 		 * Switch opened
94 		 */
95 		info("Latch open on Slot(%s)\n", p_slot->name);
96 		event_type = INT_SWITCH_OPEN;
97 	} else {
98 		/*
99 		 *  Switch closed
100 		 */
101 		info("Latch close on Slot(%s)\n", p_slot->name);
102 		event_type = INT_SWITCH_CLOSE;
103 	}
104 
105 	queue_interrupt_event(p_slot, event_type);
106 
107 	return 1;
108 }
109 
110 u8 pciehp_handle_presence_change(u8 hp_slot, struct controller *ctrl)
111 {
112 	struct slot *p_slot;
113 	u32 event_type;
114 	u8 presence_save;
115 
116 	/* Presence Change */
117 	dbg("pciehp:  Presence/Notify input change.\n");
118 
119 	p_slot = pciehp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
120 
121 	/* Switch is open, assume a presence change
122 	 * Save the presence state
123 	 */
124 	p_slot->hpc_ops->get_adapter_status(p_slot, &presence_save);
125 	if (presence_save) {
126 		/*
127 		 * Card Present
128 		 */
129 		info("Card present on Slot(%s)\n", p_slot->name);
130 		event_type = INT_PRESENCE_ON;
131 	} else {
132 		/*
133 		 * Not Present
134 		 */
135 		info("Card not present on Slot(%s)\n", p_slot->name);
136 		event_type = INT_PRESENCE_OFF;
137 	}
138 
139 	queue_interrupt_event(p_slot, event_type);
140 
141 	return 1;
142 }
143 
144 u8 pciehp_handle_power_fault(u8 hp_slot, struct controller *ctrl)
145 {
146 	struct slot *p_slot;
147 	u32 event_type;
148 
149 	/* power fault */
150 	dbg("pciehp:  Power fault interrupt received.\n");
151 
152 	p_slot = pciehp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
153 
154 	if ( !(p_slot->hpc_ops->query_power_fault(p_slot))) {
155 		/*
156 		 * power fault Cleared
157 		 */
158 		info("Power fault cleared on Slot(%s)\n", p_slot->name);
159 		event_type = INT_POWER_FAULT_CLEAR;
160 	} else {
161 		/*
162 		 *   power fault
163 		 */
164 		info("Power fault on Slot(%s)\n", p_slot->name);
165 		event_type = INT_POWER_FAULT;
166 		info("power fault bit %x set\n", hp_slot);
167 	}
168 
169 	queue_interrupt_event(p_slot, event_type);
170 
171 	return 1;
172 }
173 
174 /* The following routines constitute the bulk of the
175    hotplug controller logic
176  */
177 
178 static void set_slot_off(struct controller *ctrl, struct slot * pslot)
179 {
180 	/* turn off slot, turn on Amber LED, turn off Green LED if supported*/
181 	if (POWER_CTRL(ctrl->ctrlcap)) {
182 		if (pslot->hpc_ops->power_off_slot(pslot)) {
183 			err("%s: Issue of Slot Power Off command failed\n",
184 			    __FUNCTION__);
185 			return;
186 		}
187 	}
188 
189 	if (PWR_LED(ctrl->ctrlcap))
190 		pslot->hpc_ops->green_led_off(pslot);
191 
192 	if (ATTN_LED(ctrl->ctrlcap)) {
193 		if (pslot->hpc_ops->set_attention_status(pslot, 1)) {
194 			err("%s: Issue of Set Attention Led command failed\n",
195 			    __FUNCTION__);
196 			return;
197 		}
198 	}
199 }
200 
201 /**
202  * board_added - Called after a board has been added to the system.
203  * @p_slot: &slot where board is added
204  *
205  * Turns power on for the board.
206  * Configures board.
207  */
208 static int board_added(struct slot *p_slot)
209 {
210 	int retval = 0;
211 	struct controller *ctrl = p_slot->ctrl;
212 
213 	dbg("%s: slot device, slot offset, hp slot = %d, %d ,%d\n",
214 			__FUNCTION__, p_slot->device,
215 			ctrl->slot_device_offset, p_slot->hp_slot);
216 
217 	if (POWER_CTRL(ctrl->ctrlcap)) {
218 		/* Power on slot */
219 		retval = p_slot->hpc_ops->power_on_slot(p_slot);
220 		if (retval)
221 			return retval;
222 	}
223 
224 	if (PWR_LED(ctrl->ctrlcap))
225 		p_slot->hpc_ops->green_led_blink(p_slot);
226 
227 	/* Wait for ~1 second */
228 	msleep(1000);
229 
230 	/* Check link training status */
231 	retval = p_slot->hpc_ops->check_lnk_status(ctrl);
232 	if (retval) {
233 		err("%s: Failed to check link status\n", __FUNCTION__);
234 		set_slot_off(ctrl, p_slot);
235 		return retval;
236 	}
237 
238 	/* Check for a power fault */
239 	if (p_slot->hpc_ops->query_power_fault(p_slot)) {
240 		dbg("%s: power fault detected\n", __FUNCTION__);
241 		retval = POWER_FAILURE;
242 		goto err_exit;
243 	}
244 
245 	retval = pciehp_configure_device(p_slot);
246 	if (retval) {
247 		err("Cannot add device 0x%x:%x\n", p_slot->bus,
248 		    p_slot->device);
249 		goto err_exit;
250 	}
251 
252 	/*
253 	 * Some PCI Express root ports require fixup after hot-plug operation.
254 	 */
255 	if (pcie_mch_quirk)
256 		pci_fixup_device(pci_fixup_final, ctrl->pci_dev);
257 	if (PWR_LED(ctrl->ctrlcap))
258   		p_slot->hpc_ops->green_led_on(p_slot);
259 
260 	return 0;
261 
262 err_exit:
263 	set_slot_off(ctrl, p_slot);
264 	return retval;
265 }
266 
267 /**
268  * remove_board - Turns off slot and LEDs
269  * @p_slot: slot where board is being removed
270  */
271 static int remove_board(struct slot *p_slot)
272 {
273 	int retval = 0;
274 	struct controller *ctrl = p_slot->ctrl;
275 
276 	retval = pciehp_unconfigure_device(p_slot);
277 	if (retval)
278 		return retval;
279 
280 	dbg("In %s, hp_slot = %d\n", __FUNCTION__, p_slot->hp_slot);
281 
282 	if (POWER_CTRL(ctrl->ctrlcap)) {
283 		/* power off slot */
284 		retval = p_slot->hpc_ops->power_off_slot(p_slot);
285 		if (retval) {
286 			err("%s: Issue of Slot Disable command failed\n",
287 			    __FUNCTION__);
288 			return retval;
289 		}
290 	}
291 
292 	if (PWR_LED(ctrl->ctrlcap))
293 		/* turn off Green LED */
294 		p_slot->hpc_ops->green_led_off(p_slot);
295 
296 	return 0;
297 }
298 
299 struct power_work_info {
300 	struct slot *p_slot;
301 	struct work_struct work;
302 };
303 
304 /**
305  * pciehp_power_thread - handle pushbutton events
306  * @work: &struct work_struct describing work to be done
307  *
308  * Scheduled procedure to handle blocking stuff for the pushbuttons.
309  * Handles all pending events and exits.
310  */
311 static void pciehp_power_thread(struct work_struct *work)
312 {
313 	struct power_work_info *info =
314 		container_of(work, struct power_work_info, work);
315 	struct slot *p_slot = info->p_slot;
316 
317 	mutex_lock(&p_slot->lock);
318 	switch (p_slot->state) {
319 	case POWEROFF_STATE:
320 		mutex_unlock(&p_slot->lock);
321 		dbg("%s: disabling bus:device(%x:%x)\n",
322 		    __FUNCTION__, p_slot->bus, p_slot->device);
323 		pciehp_disable_slot(p_slot);
324 		mutex_lock(&p_slot->lock);
325 		p_slot->state = STATIC_STATE;
326 		break;
327 	case POWERON_STATE:
328 		mutex_unlock(&p_slot->lock);
329 		if (pciehp_enable_slot(p_slot) &&
330 		    PWR_LED(p_slot->ctrl->ctrlcap))
331 			p_slot->hpc_ops->green_led_off(p_slot);
332 		mutex_lock(&p_slot->lock);
333 		p_slot->state = STATIC_STATE;
334 		break;
335 	default:
336 		break;
337 	}
338 	mutex_unlock(&p_slot->lock);
339 
340 	kfree(info);
341 }
342 
343 void pciehp_queue_pushbutton_work(struct work_struct *work)
344 {
345 	struct slot *p_slot = container_of(work, struct slot, work.work);
346 	struct power_work_info *info;
347 
348 	info = kmalloc(sizeof(*info), GFP_KERNEL);
349 	if (!info) {
350 		err("%s: Cannot allocate memory\n", __FUNCTION__);
351 		return;
352 	}
353 	info->p_slot = p_slot;
354 	INIT_WORK(&info->work, pciehp_power_thread);
355 
356 	mutex_lock(&p_slot->lock);
357 	switch (p_slot->state) {
358 	case BLINKINGOFF_STATE:
359 		p_slot->state = POWEROFF_STATE;
360 		break;
361 	case BLINKINGON_STATE:
362 		p_slot->state = POWERON_STATE;
363 		break;
364 	default:
365 		goto out;
366 	}
367 	queue_work(pciehp_wq, &info->work);
368  out:
369 	mutex_unlock(&p_slot->lock);
370 }
371 
372 static int update_slot_info(struct slot *slot)
373 {
374 	struct hotplug_slot_info *info;
375 	int result;
376 
377 	info = kmalloc(sizeof(*info), GFP_KERNEL);
378 	if (!info)
379 		return -ENOMEM;
380 
381 	slot->hpc_ops->get_power_status(slot, &(info->power_status));
382 	slot->hpc_ops->get_attention_status(slot, &(info->attention_status));
383 	slot->hpc_ops->get_latch_status(slot, &(info->latch_status));
384 	slot->hpc_ops->get_adapter_status(slot, &(info->adapter_status));
385 
386 	result = pci_hp_change_slot_info(slot->hotplug_slot, info);
387 	kfree (info);
388 	return result;
389 }
390 
391 /*
392  * Note: This function must be called with slot->lock held
393  */
394 static void handle_button_press_event(struct slot *p_slot)
395 {
396 	struct controller *ctrl = p_slot->ctrl;
397 	u8 getstatus;
398 
399 	switch (p_slot->state) {
400 	case STATIC_STATE:
401 		p_slot->hpc_ops->get_power_status(p_slot, &getstatus);
402 		if (getstatus) {
403 			p_slot->state = BLINKINGOFF_STATE;
404 			info("PCI slot #%s - powering off due to button "
405 			     "press.\n", p_slot->name);
406 		} else {
407 			p_slot->state = BLINKINGON_STATE;
408 			info("PCI slot #%s - powering on due to button "
409 			     "press.\n", p_slot->name);
410 		}
411 		/* blink green LED and turn off amber */
412 		if (PWR_LED(ctrl->ctrlcap))
413 			p_slot->hpc_ops->green_led_blink(p_slot);
414 		if (ATTN_LED(ctrl->ctrlcap))
415 			p_slot->hpc_ops->set_attention_status(p_slot, 0);
416 
417 		schedule_delayed_work(&p_slot->work, 5*HZ);
418 		break;
419 	case BLINKINGOFF_STATE:
420 	case BLINKINGON_STATE:
421 		/*
422 		 * Cancel if we are still blinking; this means that we
423 		 * press the attention again before the 5 sec. limit
424 		 * expires to cancel hot-add or hot-remove
425 		 */
426 		info("Button cancel on Slot(%s)\n", p_slot->name);
427 		dbg("%s: button cancel\n", __FUNCTION__);
428 		cancel_delayed_work(&p_slot->work);
429 		if (p_slot->state == BLINKINGOFF_STATE) {
430 			if (PWR_LED(ctrl->ctrlcap))
431 				p_slot->hpc_ops->green_led_on(p_slot);
432 		} else {
433 			if (PWR_LED(ctrl->ctrlcap))
434 				p_slot->hpc_ops->green_led_off(p_slot);
435 		}
436 		if (ATTN_LED(ctrl->ctrlcap))
437 			p_slot->hpc_ops->set_attention_status(p_slot, 0);
438 		info("PCI slot #%s - action canceled due to button press\n",
439 		     p_slot->name);
440 		p_slot->state = STATIC_STATE;
441 		break;
442 	case POWEROFF_STATE:
443 	case POWERON_STATE:
444 		/*
445 		 * Ignore if the slot is on power-on or power-off state;
446 		 * this means that the previous attention button action
447 		 * to hot-add or hot-remove is undergoing
448 		 */
449 		info("Button ignore on Slot(%s)\n", p_slot->name);
450 		update_slot_info(p_slot);
451 		break;
452 	default:
453 		warn("Not a valid state\n");
454 		break;
455 	}
456 }
457 
458 /*
459  * Note: This function must be called with slot->lock held
460  */
461 static void handle_surprise_event(struct slot *p_slot)
462 {
463 	u8 getstatus;
464 	struct power_work_info *info;
465 
466 	info = kmalloc(sizeof(*info), GFP_KERNEL);
467 	if (!info) {
468 		err("%s: Cannot allocate memory\n", __FUNCTION__);
469 		return;
470 	}
471 	info->p_slot = p_slot;
472 	INIT_WORK(&info->work, pciehp_power_thread);
473 
474 	p_slot->hpc_ops->get_adapter_status(p_slot, &getstatus);
475 	if (!getstatus)
476 		p_slot->state = POWEROFF_STATE;
477 	else
478 		p_slot->state = POWERON_STATE;
479 
480 	queue_work(pciehp_wq, &info->work);
481 }
482 
483 static void interrupt_event_handler(struct work_struct *work)
484 {
485 	struct event_info *info = container_of(work, struct event_info, work);
486 	struct slot *p_slot = info->p_slot;
487 	struct controller *ctrl = p_slot->ctrl;
488 
489 	mutex_lock(&p_slot->lock);
490 	switch (info->event_type) {
491 	case INT_BUTTON_PRESS:
492 		handle_button_press_event(p_slot);
493 		break;
494 	case INT_POWER_FAULT:
495 		if (!POWER_CTRL(ctrl->ctrlcap))
496 			break;
497 		if (ATTN_LED(ctrl->ctrlcap))
498 			p_slot->hpc_ops->set_attention_status(p_slot, 1);
499 		if (PWR_LED(ctrl->ctrlcap))
500 			p_slot->hpc_ops->green_led_off(p_slot);
501 		break;
502 	case INT_PRESENCE_ON:
503 	case INT_PRESENCE_OFF:
504 		if (!HP_SUPR_RM(ctrl->ctrlcap))
505 			break;
506 		dbg("Surprise Removal\n");
507 		update_slot_info(p_slot);
508 		handle_surprise_event(p_slot);
509 		break;
510 	default:
511 		update_slot_info(p_slot);
512 		break;
513 	}
514 	mutex_unlock(&p_slot->lock);
515 
516 	kfree(info);
517 }
518 
519 int pciehp_enable_slot(struct slot *p_slot)
520 {
521 	u8 getstatus = 0;
522 	int rc;
523 
524 	/* Check to see if (latch closed, card present, power off) */
525 	mutex_lock(&p_slot->ctrl->crit_sect);
526 
527 	rc = p_slot->hpc_ops->get_adapter_status(p_slot, &getstatus);
528 	if (rc || !getstatus) {
529 		info("%s: no adapter on slot(%s)\n", __FUNCTION__,
530 		     p_slot->name);
531 		mutex_unlock(&p_slot->ctrl->crit_sect);
532 		return -ENODEV;
533 	}
534 	if (MRL_SENS(p_slot->ctrl->ctrlcap)) {
535 		rc = p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
536 		if (rc || getstatus) {
537 			info("%s: latch open on slot(%s)\n", __FUNCTION__,
538 			     p_slot->name);
539 			mutex_unlock(&p_slot->ctrl->crit_sect);
540 			return -ENODEV;
541 		}
542 	}
543 
544 	if (POWER_CTRL(p_slot->ctrl->ctrlcap)) {
545 		rc = p_slot->hpc_ops->get_power_status(p_slot, &getstatus);
546 		if (rc || getstatus) {
547 			info("%s: already enabled on slot(%s)\n", __FUNCTION__,
548 			     p_slot->name);
549 			mutex_unlock(&p_slot->ctrl->crit_sect);
550 			return -EINVAL;
551 		}
552 	}
553 
554 	p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
555 
556 	rc = board_added(p_slot);
557 	if (rc) {
558 		p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
559 	}
560 
561 	update_slot_info(p_slot);
562 
563 	mutex_unlock(&p_slot->ctrl->crit_sect);
564 	return rc;
565 }
566 
567 
568 int pciehp_disable_slot(struct slot *p_slot)
569 {
570 	u8 getstatus = 0;
571 	int ret = 0;
572 
573 	if (!p_slot->ctrl)
574 		return 1;
575 
576 	/* Check to see if (latch closed, card present, power on) */
577 	mutex_lock(&p_slot->ctrl->crit_sect);
578 
579 	if (!HP_SUPR_RM(p_slot->ctrl->ctrlcap)) {
580 		ret = p_slot->hpc_ops->get_adapter_status(p_slot, &getstatus);
581 		if (ret || !getstatus) {
582 			info("%s: no adapter on slot(%s)\n", __FUNCTION__,
583 			     p_slot->name);
584 			mutex_unlock(&p_slot->ctrl->crit_sect);
585 			return -ENODEV;
586 		}
587 	}
588 
589 	if (MRL_SENS(p_slot->ctrl->ctrlcap)) {
590 		ret = p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
591 		if (ret || getstatus) {
592 			info("%s: latch open on slot(%s)\n", __FUNCTION__,
593 			     p_slot->name);
594 			mutex_unlock(&p_slot->ctrl->crit_sect);
595 			return -ENODEV;
596 		}
597 	}
598 
599 	if (POWER_CTRL(p_slot->ctrl->ctrlcap)) {
600 		ret = p_slot->hpc_ops->get_power_status(p_slot, &getstatus);
601 		if (ret || !getstatus) {
602 			info("%s: already disabled slot(%s)\n", __FUNCTION__,
603 			     p_slot->name);
604 			mutex_unlock(&p_slot->ctrl->crit_sect);
605 			return -EINVAL;
606 		}
607 	}
608 
609 	ret = remove_board(p_slot);
610 	update_slot_info(p_slot);
611 
612 	mutex_unlock(&p_slot->ctrl->crit_sect);
613 	return ret;
614 }
615 
616 int pciehp_sysfs_enable_slot(struct slot *p_slot)
617 {
618 	int retval = -ENODEV;
619 
620 	mutex_lock(&p_slot->lock);
621 	switch (p_slot->state) {
622 	case BLINKINGON_STATE:
623 		cancel_delayed_work(&p_slot->work);
624 	case STATIC_STATE:
625 		p_slot->state = POWERON_STATE;
626 		mutex_unlock(&p_slot->lock);
627 		retval = pciehp_enable_slot(p_slot);
628 		mutex_lock(&p_slot->lock);
629 		p_slot->state = STATIC_STATE;
630 		break;
631 	case POWERON_STATE:
632 		info("Slot %s is already in powering on state\n",
633 		     p_slot->name);
634 		break;
635 	case BLINKINGOFF_STATE:
636 	case POWEROFF_STATE:
637 		info("Already enabled on slot %s\n", p_slot->name);
638 		break;
639 	default:
640 		err("Not a valid state on slot %s\n", p_slot->name);
641 		break;
642 	}
643 	mutex_unlock(&p_slot->lock);
644 
645 	return retval;
646 }
647 
648 int pciehp_sysfs_disable_slot(struct slot *p_slot)
649 {
650 	int retval = -ENODEV;
651 
652 	mutex_lock(&p_slot->lock);
653 	switch (p_slot->state) {
654 	case BLINKINGOFF_STATE:
655 		cancel_delayed_work(&p_slot->work);
656 	case STATIC_STATE:
657 		p_slot->state = POWEROFF_STATE;
658 		mutex_unlock(&p_slot->lock);
659 		retval = pciehp_disable_slot(p_slot);
660 		mutex_lock(&p_slot->lock);
661 		p_slot->state = STATIC_STATE;
662 		break;
663 	case POWEROFF_STATE:
664 		info("Slot %s is already in powering off state\n",
665 		     p_slot->name);
666 		break;
667 	case BLINKINGON_STATE:
668 	case POWERON_STATE:
669 		info("Already disabled on slot %s\n", p_slot->name);
670 		break;
671 	default:
672 		err("Not a valid state on slot %s\n", p_slot->name);
673 		break;
674 	}
675 	mutex_unlock(&p_slot->lock);
676 
677 	return retval;
678 }
679