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 static int pciehp_enable_slot(struct slot *p_slot);
41 static int pciehp_disable_slot(struct slot *p_slot);
42 
43 static int queue_interrupt_event(struct slot *p_slot, u32 event_type)
44 {
45 	struct event_info *info;
46 
47 	info = kmalloc(sizeof(*info), GFP_ATOMIC);
48 	if (!info)
49 		return -ENOMEM;
50 
51 	info->event_type = event_type;
52 	info->p_slot = p_slot;
53 	INIT_WORK(&info->work, interrupt_event_handler);
54 
55 	schedule_work(&info->work);
56 
57 	return 0;
58 }
59 
60 u8 pciehp_handle_attention_button(u8 hp_slot, struct controller *ctrl)
61 {
62 	struct slot *p_slot;
63 	u32 event_type;
64 
65 	/* Attention Button Change */
66 	dbg("pciehp:  Attention button interrupt received.\n");
67 
68 	p_slot = pciehp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
69 
70 	/*
71 	 *  Button pressed - See if need to TAKE ACTION!!!
72 	 */
73 	info("Button pressed on Slot(%s)\n", p_slot->name);
74 	event_type = INT_BUTTON_PRESS;
75 
76 	queue_interrupt_event(p_slot, event_type);
77 
78 	return 0;
79 }
80 
81 u8 pciehp_handle_switch_change(u8 hp_slot, struct controller *ctrl)
82 {
83 	struct slot *p_slot;
84 	u8 getstatus;
85 	u32 event_type;
86 
87 	/* Switch Change */
88 	dbg("pciehp:  Switch interrupt received.\n");
89 
90 	p_slot = pciehp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
91 	p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
92 
93 	if (getstatus) {
94 		/*
95 		 * Switch opened
96 		 */
97 		info("Latch open on Slot(%s)\n", p_slot->name);
98 		event_type = INT_SWITCH_OPEN;
99 	} else {
100 		/*
101 		 *  Switch closed
102 		 */
103 		info("Latch close on Slot(%s)\n", p_slot->name);
104 		event_type = INT_SWITCH_CLOSE;
105 	}
106 
107 	queue_interrupt_event(p_slot, event_type);
108 
109 	return 1;
110 }
111 
112 u8 pciehp_handle_presence_change(u8 hp_slot, struct controller *ctrl)
113 {
114 	struct slot *p_slot;
115 	u32 event_type;
116 	u8 presence_save;
117 
118 	/* Presence Change */
119 	dbg("pciehp:  Presence/Notify input change.\n");
120 
121 	p_slot = pciehp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
122 
123 	/* Switch is open, assume a presence change
124 	 * Save the presence state
125 	 */
126 	p_slot->hpc_ops->get_adapter_status(p_slot, &presence_save);
127 	if (presence_save) {
128 		/*
129 		 * Card Present
130 		 */
131 		info("Card present on Slot(%s)\n", p_slot->name);
132 		event_type = INT_PRESENCE_ON;
133 	} else {
134 		/*
135 		 * Not Present
136 		 */
137 		info("Card not present on Slot(%s)\n", p_slot->name);
138 		event_type = INT_PRESENCE_OFF;
139 	}
140 
141 	queue_interrupt_event(p_slot, event_type);
142 
143 	return 1;
144 }
145 
146 u8 pciehp_handle_power_fault(u8 hp_slot, struct controller *ctrl)
147 {
148 	struct slot *p_slot;
149 	u32 event_type;
150 
151 	/* power fault */
152 	dbg("pciehp:  Power fault interrupt received.\n");
153 
154 	p_slot = pciehp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
155 
156 	if ( !(p_slot->hpc_ops->query_power_fault(p_slot))) {
157 		/*
158 		 * power fault Cleared
159 		 */
160 		info("Power fault cleared on Slot(%s)\n", p_slot->name);
161 		event_type = INT_POWER_FAULT_CLEAR;
162 	} else {
163 		/*
164 		 *   power fault
165 		 */
166 		info("Power fault on Slot(%s)\n", p_slot->name);
167 		event_type = INT_POWER_FAULT;
168 		info("power fault bit %x set\n", hp_slot);
169 	}
170 
171 	queue_interrupt_event(p_slot, event_type);
172 
173 	return 1;
174 }
175 
176 /* The following routines constitute the bulk of the
177    hotplug controller logic
178  */
179 
180 static void set_slot_off(struct controller *ctrl, struct slot * pslot)
181 {
182 	/* turn off slot, turn on Amber LED, turn off Green LED if supported*/
183 	if (POWER_CTRL(ctrl->ctrlcap)) {
184 		if (pslot->hpc_ops->power_off_slot(pslot)) {
185 			err("%s: Issue of Slot Power Off command failed\n",
186 			    __FUNCTION__);
187 			return;
188 		}
189 	}
190 
191 	if (PWR_LED(ctrl->ctrlcap))
192 		pslot->hpc_ops->green_led_off(pslot);
193 
194 	if (ATTN_LED(ctrl->ctrlcap)) {
195 		if (pslot->hpc_ops->set_attention_status(pslot, 1)) {
196 			err("%s: Issue of Set Attention Led command failed\n",
197 			    __FUNCTION__);
198 			return;
199 		}
200 	}
201 }
202 
203 /**
204  * board_added - Called after a board has been added to the system.
205  *
206  * Turns power on for the board
207  * Configures board
208  *
209  */
210 static int board_added(struct slot *p_slot)
211 {
212 	u8 hp_slot;
213 	int retval = 0;
214 	struct controller *ctrl = p_slot->ctrl;
215 
216 	hp_slot = p_slot->device - ctrl->slot_device_offset;
217 
218 	dbg("%s: slot device, slot offset, hp slot = %d, %d ,%d\n",
219 			__FUNCTION__, p_slot->device,
220 			ctrl->slot_device_offset, hp_slot);
221 
222 	if (POWER_CTRL(ctrl->ctrlcap)) {
223 		/* Power on slot */
224 		retval = p_slot->hpc_ops->power_on_slot(p_slot);
225 		if (retval)
226 			return retval;
227 	}
228 
229 	if (PWR_LED(ctrl->ctrlcap))
230 		p_slot->hpc_ops->green_led_blink(p_slot);
231 
232 	/* Wait for ~1 second */
233 	msleep(1000);
234 
235 	/* Check link training status */
236 	retval = p_slot->hpc_ops->check_lnk_status(ctrl);
237 	if (retval) {
238 		err("%s: Failed to check link status\n", __FUNCTION__);
239 		set_slot_off(ctrl, p_slot);
240 		return retval;
241 	}
242 
243 	/* Check for a power fault */
244 	if (p_slot->hpc_ops->query_power_fault(p_slot)) {
245 		dbg("%s: power fault detected\n", __FUNCTION__);
246 		retval = POWER_FAILURE;
247 		goto err_exit;
248 	}
249 
250 	retval = pciehp_configure_device(p_slot);
251 	if (retval) {
252 		err("Cannot add device 0x%x:%x\n", p_slot->bus,
253 		    p_slot->device);
254 		goto err_exit;
255 	}
256 
257 	/*
258 	 * Some PCI Express root ports require fixup after hot-plug operation.
259 	 */
260 	if (pcie_mch_quirk)
261 		pci_fixup_device(pci_fixup_final, ctrl->pci_dev);
262 	if (PWR_LED(ctrl->ctrlcap))
263   		p_slot->hpc_ops->green_led_on(p_slot);
264 
265 	return 0;
266 
267 err_exit:
268 	set_slot_off(ctrl, p_slot);
269 	return retval;
270 }
271 
272 /**
273  * remove_board - Turns off slot and LED's
274  *
275  */
276 static int remove_board(struct slot *p_slot)
277 {
278 	u8 device;
279 	u8 hp_slot;
280 	int retval = 0;
281 	struct controller *ctrl = p_slot->ctrl;
282 
283 	retval = pciehp_unconfigure_device(p_slot);
284 	if (retval)
285 		return retval;
286 
287 	device = p_slot->device;
288 	hp_slot = p_slot->device - ctrl->slot_device_offset;
289 	p_slot = pciehp_find_slot(ctrl, hp_slot + ctrl->slot_device_offset);
290 
291 	dbg("In %s, hp_slot = %d\n", __FUNCTION__, hp_slot);
292 
293 	if (POWER_CTRL(ctrl->ctrlcap)) {
294 		/* power off slot */
295 		retval = p_slot->hpc_ops->power_off_slot(p_slot);
296 		if (retval) {
297 			err("%s: Issue of Slot Disable command failed\n",
298 			    __FUNCTION__);
299 			return retval;
300 		}
301 	}
302 
303 	if (PWR_LED(ctrl->ctrlcap))
304 		/* turn off Green LED */
305 		p_slot->hpc_ops->green_led_off(p_slot);
306 
307 	return 0;
308 }
309 
310 struct power_work_info {
311 	struct slot *p_slot;
312 	struct work_struct work;
313 };
314 
315 /**
316  * pciehp_pushbutton_thread
317  *
318  * Scheduled procedure to handle blocking stuff for the pushbuttons
319  * Handles all pending events and exits.
320  *
321  */
322 static void pciehp_power_thread(struct work_struct *work)
323 {
324 	struct power_work_info *info =
325 		container_of(work, struct power_work_info, work);
326 	struct slot *p_slot = info->p_slot;
327 
328 	mutex_lock(&p_slot->lock);
329 	switch (p_slot->state) {
330 	case POWEROFF_STATE:
331 		mutex_unlock(&p_slot->lock);
332 		dbg("%s: disabling bus:device(%x:%x)\n",
333 		    __FUNCTION__, p_slot->bus, p_slot->device);
334 		pciehp_disable_slot(p_slot);
335 		mutex_lock(&p_slot->lock);
336 		p_slot->state = STATIC_STATE;
337 		break;
338 	case POWERON_STATE:
339 		mutex_unlock(&p_slot->lock);
340 		if (pciehp_enable_slot(p_slot) &&
341 		    PWR_LED(p_slot->ctrl->ctrlcap))
342 			p_slot->hpc_ops->green_led_off(p_slot);
343 		mutex_lock(&p_slot->lock);
344 		p_slot->state = STATIC_STATE;
345 		break;
346 	default:
347 		break;
348 	}
349 	mutex_unlock(&p_slot->lock);
350 
351 	kfree(info);
352 }
353 
354 void pciehp_queue_pushbutton_work(struct work_struct *work)
355 {
356 	struct slot *p_slot = container_of(work, struct slot, work.work);
357 	struct power_work_info *info;
358 
359 	info = kmalloc(sizeof(*info), GFP_KERNEL);
360 	if (!info) {
361 		err("%s: Cannot allocate memory\n", __FUNCTION__);
362 		return;
363 	}
364 	info->p_slot = p_slot;
365 	INIT_WORK(&info->work, pciehp_power_thread);
366 
367 	mutex_lock(&p_slot->lock);
368 	switch (p_slot->state) {
369 	case BLINKINGOFF_STATE:
370 		p_slot->state = POWEROFF_STATE;
371 		break;
372 	case BLINKINGON_STATE:
373 		p_slot->state = POWERON_STATE;
374 		break;
375 	default:
376 		goto out;
377 	}
378 	queue_work(pciehp_wq, &info->work);
379  out:
380 	mutex_unlock(&p_slot->lock);
381 }
382 
383 static int update_slot_info(struct slot *slot)
384 {
385 	struct hotplug_slot_info *info;
386 	int result;
387 
388 	info = kmalloc(sizeof(*info), GFP_KERNEL);
389 	if (!info)
390 		return -ENOMEM;
391 
392 	slot->hpc_ops->get_power_status(slot, &(info->power_status));
393 	slot->hpc_ops->get_attention_status(slot, &(info->attention_status));
394 	slot->hpc_ops->get_latch_status(slot, &(info->latch_status));
395 	slot->hpc_ops->get_adapter_status(slot, &(info->adapter_status));
396 
397 	result = pci_hp_change_slot_info(slot->hotplug_slot, info);
398 	kfree (info);
399 	return result;
400 }
401 
402 /*
403  * Note: This function must be called with slot->lock held
404  */
405 static void handle_button_press_event(struct slot *p_slot)
406 {
407 	struct controller *ctrl = p_slot->ctrl;
408 	u8 getstatus;
409 
410 	switch (p_slot->state) {
411 	case STATIC_STATE:
412 		p_slot->hpc_ops->get_power_status(p_slot, &getstatus);
413 		if (getstatus) {
414 			p_slot->state = BLINKINGOFF_STATE;
415 			info("PCI slot #%s - powering off due to button "
416 			     "press.\n", p_slot->name);
417 		} else {
418 			p_slot->state = BLINKINGON_STATE;
419 			info("PCI slot #%s - powering on due to button "
420 			     "press.\n", p_slot->name);
421 		}
422 		/* blink green LED and turn off amber */
423 		if (PWR_LED(ctrl->ctrlcap))
424 			p_slot->hpc_ops->green_led_blink(p_slot);
425 		if (ATTN_LED(ctrl->ctrlcap))
426 			p_slot->hpc_ops->set_attention_status(p_slot, 0);
427 
428 		schedule_delayed_work(&p_slot->work, 5*HZ);
429 		break;
430 	case BLINKINGOFF_STATE:
431 	case BLINKINGON_STATE:
432 		/*
433 		 * Cancel if we are still blinking; this means that we
434 		 * press the attention again before the 5 sec. limit
435 		 * expires to cancel hot-add or hot-remove
436 		 */
437 		info("Button cancel on Slot(%s)\n", p_slot->name);
438 		dbg("%s: button cancel\n", __FUNCTION__);
439 		cancel_delayed_work(&p_slot->work);
440 		if (p_slot->state == BLINKINGOFF_STATE) {
441 			if (PWR_LED(ctrl->ctrlcap))
442 				p_slot->hpc_ops->green_led_on(p_slot);
443 		} else {
444 			if (PWR_LED(ctrl->ctrlcap))
445 				p_slot->hpc_ops->green_led_off(p_slot);
446 		}
447 		if (ATTN_LED(ctrl->ctrlcap))
448 			p_slot->hpc_ops->set_attention_status(p_slot, 0);
449 		info("PCI slot #%s - action canceled due to button press\n",
450 		     p_slot->name);
451 		p_slot->state = STATIC_STATE;
452 		break;
453 	case POWEROFF_STATE:
454 	case POWERON_STATE:
455 		/*
456 		 * Ignore if the slot is on power-on or power-off state;
457 		 * this means that the previous attention button action
458 		 * to hot-add or hot-remove is undergoing
459 		 */
460 		info("Button ignore on Slot(%s)\n", p_slot->name);
461 		update_slot_info(p_slot);
462 		break;
463 	default:
464 		warn("Not a valid state\n");
465 		break;
466 	}
467 }
468 
469 /*
470  * Note: This function must be called with slot->lock held
471  */
472 static void handle_surprise_event(struct slot *p_slot)
473 {
474 	u8 getstatus;
475 	struct power_work_info *info;
476 
477 	info = kmalloc(sizeof(*info), GFP_KERNEL);
478 	if (!info) {
479 		err("%s: Cannot allocate memory\n", __FUNCTION__);
480 		return;
481 	}
482 	info->p_slot = p_slot;
483 	INIT_WORK(&info->work, pciehp_power_thread);
484 
485 	p_slot->hpc_ops->get_adapter_status(p_slot, &getstatus);
486 	if (!getstatus)
487 		p_slot->state = POWEROFF_STATE;
488 	else
489 		p_slot->state = POWERON_STATE;
490 
491 	queue_work(pciehp_wq, &info->work);
492 }
493 
494 static void interrupt_event_handler(struct work_struct *work)
495 {
496 	struct event_info *info = container_of(work, struct event_info, work);
497 	struct slot *p_slot = info->p_slot;
498 	struct controller *ctrl = p_slot->ctrl;
499 
500 	mutex_lock(&p_slot->lock);
501 	switch (info->event_type) {
502 	case INT_BUTTON_PRESS:
503 		handle_button_press_event(p_slot);
504 		break;
505 	case INT_POWER_FAULT:
506 		if (!POWER_CTRL(ctrl->ctrlcap))
507 			break;
508 		if (ATTN_LED(ctrl->ctrlcap))
509 			p_slot->hpc_ops->set_attention_status(p_slot, 1);
510 		if (PWR_LED(ctrl->ctrlcap))
511 			p_slot->hpc_ops->green_led_off(p_slot);
512 		break;
513 	case INT_PRESENCE_ON:
514 	case INT_PRESENCE_OFF:
515 		if (!HP_SUPR_RM(ctrl->ctrlcap))
516 			break;
517 		dbg("Surprise Removal\n");
518 		update_slot_info(p_slot);
519 		handle_surprise_event(p_slot);
520 		break;
521 	default:
522 		update_slot_info(p_slot);
523 		break;
524 	}
525 	mutex_unlock(&p_slot->lock);
526 
527 	kfree(info);
528 }
529 
530 int pciehp_enable_slot(struct slot *p_slot)
531 {
532 	u8 getstatus = 0;
533 	int rc;
534 
535 	/* Check to see if (latch closed, card present, power off) */
536 	mutex_lock(&p_slot->ctrl->crit_sect);
537 
538 	rc = p_slot->hpc_ops->get_adapter_status(p_slot, &getstatus);
539 	if (rc || !getstatus) {
540 		info("%s: no adapter on slot(%s)\n", __FUNCTION__,
541 		     p_slot->name);
542 		mutex_unlock(&p_slot->ctrl->crit_sect);
543 		return -ENODEV;
544 	}
545 	if (MRL_SENS(p_slot->ctrl->ctrlcap)) {
546 		rc = p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
547 		if (rc || getstatus) {
548 			info("%s: latch open on slot(%s)\n", __FUNCTION__,
549 			     p_slot->name);
550 			mutex_unlock(&p_slot->ctrl->crit_sect);
551 			return -ENODEV;
552 		}
553 	}
554 
555 	if (POWER_CTRL(p_slot->ctrl->ctrlcap)) {
556 		rc = p_slot->hpc_ops->get_power_status(p_slot, &getstatus);
557 		if (rc || getstatus) {
558 			info("%s: already enabled on slot(%s)\n", __FUNCTION__,
559 			     p_slot->name);
560 			mutex_unlock(&p_slot->ctrl->crit_sect);
561 			return -EINVAL;
562 		}
563 	}
564 
565 	p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
566 
567 	rc = board_added(p_slot);
568 	if (rc) {
569 		p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
570 	}
571 
572 	update_slot_info(p_slot);
573 
574 	mutex_unlock(&p_slot->ctrl->crit_sect);
575 	return rc;
576 }
577 
578 
579 int pciehp_disable_slot(struct slot *p_slot)
580 {
581 	u8 getstatus = 0;
582 	int ret = 0;
583 
584 	if (!p_slot->ctrl)
585 		return 1;
586 
587 	/* Check to see if (latch closed, card present, power on) */
588 	mutex_lock(&p_slot->ctrl->crit_sect);
589 
590 	if (!HP_SUPR_RM(p_slot->ctrl->ctrlcap)) {
591 		ret = p_slot->hpc_ops->get_adapter_status(p_slot, &getstatus);
592 		if (ret || !getstatus) {
593 			info("%s: no adapter on slot(%s)\n", __FUNCTION__,
594 			     p_slot->name);
595 			mutex_unlock(&p_slot->ctrl->crit_sect);
596 			return -ENODEV;
597 		}
598 	}
599 
600 	if (MRL_SENS(p_slot->ctrl->ctrlcap)) {
601 		ret = p_slot->hpc_ops->get_latch_status(p_slot, &getstatus);
602 		if (ret || getstatus) {
603 			info("%s: latch open on slot(%s)\n", __FUNCTION__,
604 			     p_slot->name);
605 			mutex_unlock(&p_slot->ctrl->crit_sect);
606 			return -ENODEV;
607 		}
608 	}
609 
610 	if (POWER_CTRL(p_slot->ctrl->ctrlcap)) {
611 		ret = p_slot->hpc_ops->get_power_status(p_slot, &getstatus);
612 		if (ret || !getstatus) {
613 			info("%s: already disabled slot(%s)\n", __FUNCTION__,
614 			     p_slot->name);
615 			mutex_unlock(&p_slot->ctrl->crit_sect);
616 			return -EINVAL;
617 		}
618 	}
619 
620 	ret = remove_board(p_slot);
621 	update_slot_info(p_slot);
622 
623 	mutex_unlock(&p_slot->ctrl->crit_sect);
624 	return ret;
625 }
626 
627 int pciehp_sysfs_enable_slot(struct slot *p_slot)
628 {
629 	int retval = -ENODEV;
630 
631 	mutex_lock(&p_slot->lock);
632 	switch (p_slot->state) {
633 	case BLINKINGON_STATE:
634 		cancel_delayed_work(&p_slot->work);
635 	case STATIC_STATE:
636 		p_slot->state = POWERON_STATE;
637 		mutex_unlock(&p_slot->lock);
638 		retval = pciehp_enable_slot(p_slot);
639 		mutex_lock(&p_slot->lock);
640 		p_slot->state = STATIC_STATE;
641 		break;
642 	case POWERON_STATE:
643 		info("Slot %s is already in powering on state\n",
644 		     p_slot->name);
645 		break;
646 	case BLINKINGOFF_STATE:
647 	case POWEROFF_STATE:
648 		info("Already enabled on slot %s\n", p_slot->name);
649 		break;
650 	default:
651 		err("Not a valid state on slot %s\n", p_slot->name);
652 		break;
653 	}
654 	mutex_unlock(&p_slot->lock);
655 
656 	return retval;
657 }
658 
659 int pciehp_sysfs_disable_slot(struct slot *p_slot)
660 {
661 	int retval = -ENODEV;
662 
663 	mutex_lock(&p_slot->lock);
664 	switch (p_slot->state) {
665 	case BLINKINGOFF_STATE:
666 		cancel_delayed_work(&p_slot->work);
667 	case STATIC_STATE:
668 		p_slot->state = POWEROFF_STATE;
669 		mutex_unlock(&p_slot->lock);
670 		retval = pciehp_disable_slot(p_slot);
671 		mutex_lock(&p_slot->lock);
672 		p_slot->state = STATIC_STATE;
673 		break;
674 	case POWEROFF_STATE:
675 		info("Slot %s is already in powering off state\n",
676 		     p_slot->name);
677 		break;
678 	case BLINKINGON_STATE:
679 	case POWERON_STATE:
680 		info("Already disabled on slot %s\n", p_slot->name);
681 		break;
682 	default:
683 		err("Not a valid state on slot %s\n", p_slot->name);
684 		break;
685 	}
686 	mutex_unlock(&p_slot->lock);
687 
688 	return retval;
689 }
690