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/pci.h>
34 #include <linux/workqueue.h>
35 #include "../pci.h"
36 #include "pciehp.h"
37 
38 static void interrupt_event_handler(struct work_struct *work);
39 
40 static int queue_interrupt_event(struct slot *p_slot, u32 event_type)
41 {
42 	struct event_info *info;
43 
44 	info = kmalloc(sizeof(*info), GFP_ATOMIC);
45 	if (!info)
46 		return -ENOMEM;
47 
48 	info->event_type = event_type;
49 	info->p_slot = p_slot;
50 	INIT_WORK(&info->work, interrupt_event_handler);
51 
52 	schedule_work(&info->work);
53 
54 	return 0;
55 }
56 
57 u8 pciehp_handle_attention_button(struct slot *p_slot)
58 {
59 	u32 event_type;
60 	struct controller *ctrl = p_slot->ctrl;
61 
62 	/* Attention Button Change */
63 	ctrl_dbg(ctrl, "Attention button interrupt received\n");
64 
65 	/*
66 	 *  Button pressed - See if need to TAKE ACTION!!!
67 	 */
68 	ctrl_info(ctrl, "Button pressed on Slot(%s)\n", slot_name(p_slot));
69 	event_type = INT_BUTTON_PRESS;
70 
71 	queue_interrupt_event(p_slot, event_type);
72 
73 	return 0;
74 }
75 
76 u8 pciehp_handle_switch_change(struct slot *p_slot)
77 {
78 	u8 getstatus;
79 	u32 event_type;
80 	struct controller *ctrl = p_slot->ctrl;
81 
82 	/* Switch Change */
83 	ctrl_dbg(ctrl, "Switch interrupt received\n");
84 
85 	pciehp_get_latch_status(p_slot, &getstatus);
86 	if (getstatus) {
87 		/*
88 		 * Switch opened
89 		 */
90 		ctrl_info(ctrl, "Latch open on Slot(%s)\n", slot_name(p_slot));
91 		event_type = INT_SWITCH_OPEN;
92 	} else {
93 		/*
94 		 *  Switch closed
95 		 */
96 		ctrl_info(ctrl, "Latch close on Slot(%s)\n", slot_name(p_slot));
97 		event_type = INT_SWITCH_CLOSE;
98 	}
99 
100 	queue_interrupt_event(p_slot, event_type);
101 
102 	return 1;
103 }
104 
105 u8 pciehp_handle_presence_change(struct slot *p_slot)
106 {
107 	u32 event_type;
108 	u8 presence_save;
109 	struct controller *ctrl = p_slot->ctrl;
110 
111 	/* Presence Change */
112 	ctrl_dbg(ctrl, "Presence/Notify input change\n");
113 
114 	/* Switch is open, assume a presence change
115 	 * Save the presence state
116 	 */
117 	pciehp_get_adapter_status(p_slot, &presence_save);
118 	if (presence_save) {
119 		/*
120 		 * Card Present
121 		 */
122 		ctrl_info(ctrl, "Card present on Slot(%s)\n", slot_name(p_slot));
123 		event_type = INT_PRESENCE_ON;
124 	} else {
125 		/*
126 		 * Not Present
127 		 */
128 		ctrl_info(ctrl, "Card not present on Slot(%s)\n",
129 			  slot_name(p_slot));
130 		event_type = INT_PRESENCE_OFF;
131 	}
132 
133 	queue_interrupt_event(p_slot, event_type);
134 
135 	return 1;
136 }
137 
138 u8 pciehp_handle_power_fault(struct slot *p_slot)
139 {
140 	u32 event_type;
141 	struct controller *ctrl = p_slot->ctrl;
142 
143 	/* power fault */
144 	ctrl_dbg(ctrl, "Power fault interrupt received\n");
145 
146 	if (!pciehp_query_power_fault(p_slot)) {
147 		/*
148 		 * power fault Cleared
149 		 */
150 		ctrl_info(ctrl, "Power fault cleared on Slot(%s)\n",
151 			  slot_name(p_slot));
152 		event_type = INT_POWER_FAULT_CLEAR;
153 	} else {
154 		/*
155 		 *   power fault
156 		 */
157 		ctrl_info(ctrl, "Power fault on Slot(%s)\n", slot_name(p_slot));
158 		event_type = INT_POWER_FAULT;
159 		ctrl_info(ctrl, "Power fault bit %x set\n", 0);
160 	}
161 
162 	queue_interrupt_event(p_slot, event_type);
163 
164 	return 1;
165 }
166 
167 /* The following routines constitute the bulk of the
168    hotplug controller logic
169  */
170 
171 static void set_slot_off(struct controller *ctrl, struct slot * pslot)
172 {
173 	/* turn off slot, turn on Amber LED, turn off Green LED if supported*/
174 	if (POWER_CTRL(ctrl)) {
175 		if (pciehp_power_off_slot(pslot)) {
176 			ctrl_err(ctrl,
177 				 "Issue of Slot Power Off command failed\n");
178 			return;
179 		}
180 		/*
181 		 * After turning power off, we must wait for at least 1 second
182 		 * before taking any action that relies on power having been
183 		 * removed from the slot/adapter.
184 		 */
185 		msleep(1000);
186 	}
187 
188 	if (PWR_LED(ctrl))
189 		pciehp_green_led_off(pslot);
190 
191 	if (ATTN_LED(ctrl)) {
192 		if (pciehp_set_attention_status(pslot, 1)) {
193 			ctrl_err(ctrl,
194 				 "Issue of Set Attention Led command failed\n");
195 			return;
196 		}
197 	}
198 }
199 
200 /**
201  * board_added - Called after a board has been added to the system.
202  * @p_slot: &slot where board is added
203  *
204  * Turns power on for the board.
205  * Configures board.
206  */
207 static int board_added(struct slot *p_slot)
208 {
209 	int retval = 0;
210 	struct controller *ctrl = p_slot->ctrl;
211 	struct pci_bus *parent = ctrl->pcie->port->subordinate;
212 
213 	if (POWER_CTRL(ctrl)) {
214 		/* Power on slot */
215 		retval = pciehp_power_on_slot(p_slot);
216 		if (retval)
217 			return retval;
218 	}
219 
220 	if (PWR_LED(ctrl))
221 		pciehp_green_led_blink(p_slot);
222 
223 	/* Check link training status */
224 	retval = pciehp_check_link_status(ctrl);
225 	if (retval) {
226 		ctrl_err(ctrl, "Failed to check link status\n");
227 		set_slot_off(ctrl, p_slot);
228 		return retval;
229 	}
230 
231 	/* Check for a power fault */
232 	if (pciehp_query_power_fault(p_slot)) {
233 		ctrl_dbg(ctrl, "Power fault detected\n");
234 		retval = -EIO;
235 		goto err_exit;
236 	}
237 
238 	retval = pciehp_configure_device(p_slot);
239 	if (retval) {
240 		ctrl_err(ctrl, "Cannot add device at %04x:%02x:00\n",
241 			 pci_domain_nr(parent), parent->number);
242 		goto err_exit;
243 	}
244 
245 	if (PWR_LED(ctrl))
246 		pciehp_green_led_on(p_slot);
247 
248 	return 0;
249 
250 err_exit:
251 	set_slot_off(ctrl, p_slot);
252 	return retval;
253 }
254 
255 /**
256  * remove_board - Turns off slot and LEDs
257  * @p_slot: slot where board is being removed
258  */
259 static int remove_board(struct slot *p_slot)
260 {
261 	int retval = 0;
262 	struct controller *ctrl = p_slot->ctrl;
263 
264 	retval = pciehp_unconfigure_device(p_slot);
265 	if (retval)
266 		return retval;
267 
268 	if (POWER_CTRL(ctrl)) {
269 		/* power off slot */
270 		retval = pciehp_power_off_slot(p_slot);
271 		if (retval) {
272 			ctrl_err(ctrl,
273 				 "Issue of Slot Disable command failed\n");
274 			return retval;
275 		}
276 		/*
277 		 * After turning power off, we must wait for at least 1 second
278 		 * before taking any action that relies on power having been
279 		 * removed from the slot/adapter.
280 		 */
281 		msleep(1000);
282 	}
283 
284 	/* turn off Green LED */
285 	if (PWR_LED(ctrl))
286 		pciehp_green_led_off(p_slot);
287 
288 	return 0;
289 }
290 
291 struct power_work_info {
292 	struct slot *p_slot;
293 	struct work_struct work;
294 };
295 
296 /**
297  * pciehp_power_thread - handle pushbutton events
298  * @work: &struct work_struct describing work to be done
299  *
300  * Scheduled procedure to handle blocking stuff for the pushbuttons.
301  * Handles all pending events and exits.
302  */
303 static void pciehp_power_thread(struct work_struct *work)
304 {
305 	struct power_work_info *info =
306 		container_of(work, struct power_work_info, work);
307 	struct slot *p_slot = info->p_slot;
308 
309 	mutex_lock(&p_slot->lock);
310 	switch (p_slot->state) {
311 	case POWEROFF_STATE:
312 		mutex_unlock(&p_slot->lock);
313 		ctrl_dbg(p_slot->ctrl,
314 			 "Disabling domain:bus:device=%04x:%02x:00\n",
315 			 pci_domain_nr(p_slot->ctrl->pcie->port->subordinate),
316 			 p_slot->ctrl->pcie->port->subordinate->number);
317 		pciehp_disable_slot(p_slot);
318 		mutex_lock(&p_slot->lock);
319 		p_slot->state = STATIC_STATE;
320 		break;
321 	case POWERON_STATE:
322 		mutex_unlock(&p_slot->lock);
323 		if (pciehp_enable_slot(p_slot) && PWR_LED(p_slot->ctrl))
324 			pciehp_green_led_off(p_slot);
325 		mutex_lock(&p_slot->lock);
326 		p_slot->state = STATIC_STATE;
327 		break;
328 	default:
329 		break;
330 	}
331 	mutex_unlock(&p_slot->lock);
332 
333 	kfree(info);
334 }
335 
336 void pciehp_queue_pushbutton_work(struct work_struct *work)
337 {
338 	struct slot *p_slot = container_of(work, struct slot, work.work);
339 	struct power_work_info *info;
340 
341 	info = kmalloc(sizeof(*info), GFP_KERNEL);
342 	if (!info) {
343 		ctrl_err(p_slot->ctrl, "%s: Cannot allocate memory\n",
344 			 __func__);
345 		return;
346 	}
347 	info->p_slot = p_slot;
348 	INIT_WORK(&info->work, pciehp_power_thread);
349 
350 	mutex_lock(&p_slot->lock);
351 	switch (p_slot->state) {
352 	case BLINKINGOFF_STATE:
353 		p_slot->state = POWEROFF_STATE;
354 		break;
355 	case BLINKINGON_STATE:
356 		p_slot->state = POWERON_STATE;
357 		break;
358 	default:
359 		goto out;
360 	}
361 	queue_work(pciehp_wq, &info->work);
362  out:
363 	mutex_unlock(&p_slot->lock);
364 }
365 
366 static int update_slot_info(struct slot *slot)
367 {
368 	struct hotplug_slot_info *info;
369 	int result;
370 
371 	info = kmalloc(sizeof(*info), GFP_KERNEL);
372 	if (!info)
373 		return -ENOMEM;
374 
375 	pciehp_get_power_status(slot, &info->power_status);
376 	pciehp_get_attention_status(slot, &info->attention_status);
377 	pciehp_get_latch_status(slot, &info->latch_status);
378 	pciehp_get_adapter_status(slot, &info->adapter_status);
379 
380 	result = pci_hp_change_slot_info(slot->hotplug_slot, info);
381 	kfree (info);
382 	return result;
383 }
384 
385 /*
386  * Note: This function must be called with slot->lock held
387  */
388 static void handle_button_press_event(struct slot *p_slot)
389 {
390 	struct controller *ctrl = p_slot->ctrl;
391 	u8 getstatus;
392 
393 	switch (p_slot->state) {
394 	case STATIC_STATE:
395 		pciehp_get_power_status(p_slot, &getstatus);
396 		if (getstatus) {
397 			p_slot->state = BLINKINGOFF_STATE;
398 			ctrl_info(ctrl,
399 				  "PCI slot #%s - powering off due to button "
400 				  "press.\n", slot_name(p_slot));
401 		} else {
402 			p_slot->state = BLINKINGON_STATE;
403 			ctrl_info(ctrl,
404 				  "PCI slot #%s - powering on due to button "
405 				  "press.\n", slot_name(p_slot));
406 		}
407 		/* blink green LED and turn off amber */
408 		if (PWR_LED(ctrl))
409 			pciehp_green_led_blink(p_slot);
410 		if (ATTN_LED(ctrl))
411 			pciehp_set_attention_status(p_slot, 0);
412 
413 		schedule_delayed_work(&p_slot->work, 5*HZ);
414 		break;
415 	case BLINKINGOFF_STATE:
416 	case BLINKINGON_STATE:
417 		/*
418 		 * Cancel if we are still blinking; this means that we
419 		 * press the attention again before the 5 sec. limit
420 		 * expires to cancel hot-add or hot-remove
421 		 */
422 		ctrl_info(ctrl, "Button cancel on Slot(%s)\n", slot_name(p_slot));
423 		cancel_delayed_work(&p_slot->work);
424 		if (p_slot->state == BLINKINGOFF_STATE) {
425 			if (PWR_LED(ctrl))
426 				pciehp_green_led_on(p_slot);
427 		} else {
428 			if (PWR_LED(ctrl))
429 				pciehp_green_led_off(p_slot);
430 		}
431 		if (ATTN_LED(ctrl))
432 			pciehp_set_attention_status(p_slot, 0);
433 		ctrl_info(ctrl, "PCI slot #%s - action canceled "
434 			  "due to button press\n", slot_name(p_slot));
435 		p_slot->state = STATIC_STATE;
436 		break;
437 	case POWEROFF_STATE:
438 	case POWERON_STATE:
439 		/*
440 		 * Ignore if the slot is on power-on or power-off state;
441 		 * this means that the previous attention button action
442 		 * to hot-add or hot-remove is undergoing
443 		 */
444 		ctrl_info(ctrl, "Button ignore on Slot(%s)\n", slot_name(p_slot));
445 		update_slot_info(p_slot);
446 		break;
447 	default:
448 		ctrl_warn(ctrl, "Not a valid state\n");
449 		break;
450 	}
451 }
452 
453 /*
454  * Note: This function must be called with slot->lock held
455  */
456 static void handle_surprise_event(struct slot *p_slot)
457 {
458 	u8 getstatus;
459 	struct power_work_info *info;
460 
461 	info = kmalloc(sizeof(*info), GFP_KERNEL);
462 	if (!info) {
463 		ctrl_err(p_slot->ctrl, "%s: Cannot allocate memory\n",
464 			 __func__);
465 		return;
466 	}
467 	info->p_slot = p_slot;
468 	INIT_WORK(&info->work, pciehp_power_thread);
469 
470 	pciehp_get_adapter_status(p_slot, &getstatus);
471 	if (!getstatus)
472 		p_slot->state = POWEROFF_STATE;
473 	else
474 		p_slot->state = POWERON_STATE;
475 
476 	queue_work(pciehp_wq, &info->work);
477 }
478 
479 static void interrupt_event_handler(struct work_struct *work)
480 {
481 	struct event_info *info = container_of(work, struct event_info, work);
482 	struct slot *p_slot = info->p_slot;
483 	struct controller *ctrl = p_slot->ctrl;
484 
485 	mutex_lock(&p_slot->lock);
486 	switch (info->event_type) {
487 	case INT_BUTTON_PRESS:
488 		handle_button_press_event(p_slot);
489 		break;
490 	case INT_POWER_FAULT:
491 		if (!POWER_CTRL(ctrl))
492 			break;
493 		if (ATTN_LED(ctrl))
494 			pciehp_set_attention_status(p_slot, 1);
495 		if (PWR_LED(ctrl))
496 			pciehp_green_led_off(p_slot);
497 		break;
498 	case INT_PRESENCE_ON:
499 	case INT_PRESENCE_OFF:
500 		if (!HP_SUPR_RM(ctrl))
501 			break;
502 		ctrl_dbg(ctrl, "Surprise Removal\n");
503 		update_slot_info(p_slot);
504 		handle_surprise_event(p_slot);
505 		break;
506 	default:
507 		update_slot_info(p_slot);
508 		break;
509 	}
510 	mutex_unlock(&p_slot->lock);
511 
512 	kfree(info);
513 }
514 
515 int pciehp_enable_slot(struct slot *p_slot)
516 {
517 	u8 getstatus = 0;
518 	int rc;
519 	struct controller *ctrl = p_slot->ctrl;
520 
521 	rc = pciehp_get_adapter_status(p_slot, &getstatus);
522 	if (rc || !getstatus) {
523 		ctrl_info(ctrl, "No adapter on slot(%s)\n", slot_name(p_slot));
524 		return -ENODEV;
525 	}
526 	if (MRL_SENS(p_slot->ctrl)) {
527 		rc = pciehp_get_latch_status(p_slot, &getstatus);
528 		if (rc || getstatus) {
529 			ctrl_info(ctrl, "Latch open on slot(%s)\n",
530 				  slot_name(p_slot));
531 			return -ENODEV;
532 		}
533 	}
534 
535 	if (POWER_CTRL(p_slot->ctrl)) {
536 		rc = pciehp_get_power_status(p_slot, &getstatus);
537 		if (rc || getstatus) {
538 			ctrl_info(ctrl, "Already enabled on slot(%s)\n",
539 				  slot_name(p_slot));
540 			return -EINVAL;
541 		}
542 	}
543 
544 	pciehp_get_latch_status(p_slot, &getstatus);
545 
546 	rc = board_added(p_slot);
547 	if (rc) {
548 		pciehp_get_latch_status(p_slot, &getstatus);
549 	}
550 
551 	update_slot_info(p_slot);
552 
553 	return rc;
554 }
555 
556 
557 int pciehp_disable_slot(struct slot *p_slot)
558 {
559 	u8 getstatus = 0;
560 	int ret = 0;
561 	struct controller *ctrl = p_slot->ctrl;
562 
563 	if (!p_slot->ctrl)
564 		return 1;
565 
566 	if (!HP_SUPR_RM(p_slot->ctrl)) {
567 		ret = pciehp_get_adapter_status(p_slot, &getstatus);
568 		if (ret || !getstatus) {
569 			ctrl_info(ctrl, "No adapter on slot(%s)\n",
570 				  slot_name(p_slot));
571 			return -ENODEV;
572 		}
573 	}
574 
575 	if (MRL_SENS(p_slot->ctrl)) {
576 		ret = pciehp_get_latch_status(p_slot, &getstatus);
577 		if (ret || getstatus) {
578 			ctrl_info(ctrl, "Latch open on slot(%s)\n",
579 				  slot_name(p_slot));
580 			return -ENODEV;
581 		}
582 	}
583 
584 	if (POWER_CTRL(p_slot->ctrl)) {
585 		ret = pciehp_get_power_status(p_slot, &getstatus);
586 		if (ret || !getstatus) {
587 			ctrl_info(ctrl, "Already disabled on slot(%s)\n",
588 				  slot_name(p_slot));
589 			return -EINVAL;
590 		}
591 	}
592 
593 	ret = remove_board(p_slot);
594 	update_slot_info(p_slot);
595 
596 	return ret;
597 }
598 
599 int pciehp_sysfs_enable_slot(struct slot *p_slot)
600 {
601 	int retval = -ENODEV;
602 	struct controller *ctrl = p_slot->ctrl;
603 
604 	mutex_lock(&p_slot->lock);
605 	switch (p_slot->state) {
606 	case BLINKINGON_STATE:
607 		cancel_delayed_work(&p_slot->work);
608 	case STATIC_STATE:
609 		p_slot->state = POWERON_STATE;
610 		mutex_unlock(&p_slot->lock);
611 		retval = pciehp_enable_slot(p_slot);
612 		mutex_lock(&p_slot->lock);
613 		p_slot->state = STATIC_STATE;
614 		break;
615 	case POWERON_STATE:
616 		ctrl_info(ctrl, "Slot %s is already in powering on state\n",
617 			  slot_name(p_slot));
618 		break;
619 	case BLINKINGOFF_STATE:
620 	case POWEROFF_STATE:
621 		ctrl_info(ctrl, "Already enabled on slot %s\n",
622 			  slot_name(p_slot));
623 		break;
624 	default:
625 		ctrl_err(ctrl, "Not a valid state on slot %s\n",
626 			 slot_name(p_slot));
627 		break;
628 	}
629 	mutex_unlock(&p_slot->lock);
630 
631 	return retval;
632 }
633 
634 int pciehp_sysfs_disable_slot(struct slot *p_slot)
635 {
636 	int retval = -ENODEV;
637 	struct controller *ctrl = p_slot->ctrl;
638 
639 	mutex_lock(&p_slot->lock);
640 	switch (p_slot->state) {
641 	case BLINKINGOFF_STATE:
642 		cancel_delayed_work(&p_slot->work);
643 	case STATIC_STATE:
644 		p_slot->state = POWEROFF_STATE;
645 		mutex_unlock(&p_slot->lock);
646 		retval = pciehp_disable_slot(p_slot);
647 		mutex_lock(&p_slot->lock);
648 		p_slot->state = STATIC_STATE;
649 		break;
650 	case POWEROFF_STATE:
651 		ctrl_info(ctrl, "Slot %s is already in powering off state\n",
652 			  slot_name(p_slot));
653 		break;
654 	case BLINKINGON_STATE:
655 	case POWERON_STATE:
656 		ctrl_info(ctrl, "Already disabled on slot %s\n",
657 			  slot_name(p_slot));
658 		break;
659 	default:
660 		ctrl_err(ctrl, "Not a valid state on slot %s\n",
661 			 slot_name(p_slot));
662 		break;
663 	}
664 	mutex_unlock(&p_slot->lock);
665 
666 	return retval;
667 }
668