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/slab.h>
34 #include <linux/pci.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 	queue_work(p_slot->wq, &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 	ctrl_err(ctrl, "Power fault on slot %s\n", slot_name(p_slot));
146 	event_type = INT_POWER_FAULT;
147 	ctrl_info(ctrl, "Power fault bit %x set\n", 0);
148 	queue_interrupt_event(p_slot, event_type);
149 
150 	return 1;
151 }
152 
153 /* The following routines constitute the bulk of the
154    hotplug controller logic
155  */
156 
157 static void set_slot_off(struct controller *ctrl, struct slot * pslot)
158 {
159 	/* turn off slot, turn on Amber LED, turn off Green LED if supported*/
160 	if (POWER_CTRL(ctrl)) {
161 		if (pciehp_power_off_slot(pslot)) {
162 			ctrl_err(ctrl,
163 				 "Issue of Slot Power Off command failed\n");
164 			return;
165 		}
166 		/*
167 		 * After turning power off, we must wait for at least 1 second
168 		 * before taking any action that relies on power having been
169 		 * removed from the slot/adapter.
170 		 */
171 		msleep(1000);
172 	}
173 
174 	if (PWR_LED(ctrl))
175 		pciehp_green_led_off(pslot);
176 
177 	if (ATTN_LED(ctrl)) {
178 		if (pciehp_set_attention_status(pslot, 1)) {
179 			ctrl_err(ctrl,
180 				 "Issue of Set Attention Led command failed\n");
181 			return;
182 		}
183 	}
184 }
185 
186 /**
187  * board_added - Called after a board has been added to the system.
188  * @p_slot: &slot where board is added
189  *
190  * Turns power on for the board.
191  * Configures board.
192  */
193 static int board_added(struct slot *p_slot)
194 {
195 	int retval = 0;
196 	struct controller *ctrl = p_slot->ctrl;
197 	struct pci_bus *parent = ctrl->pcie->port->subordinate;
198 
199 	if (POWER_CTRL(ctrl)) {
200 		/* Power on slot */
201 		retval = pciehp_power_on_slot(p_slot);
202 		if (retval)
203 			return retval;
204 	}
205 
206 	if (PWR_LED(ctrl))
207 		pciehp_green_led_blink(p_slot);
208 
209 	/* Check link training status */
210 	retval = pciehp_check_link_status(ctrl);
211 	if (retval) {
212 		ctrl_err(ctrl, "Failed to check link status\n");
213 		goto err_exit;
214 	}
215 
216 	/* Check for a power fault */
217 	if (ctrl->power_fault_detected || pciehp_query_power_fault(p_slot)) {
218 		ctrl_err(ctrl, "Power fault on slot %s\n", slot_name(p_slot));
219 		retval = -EIO;
220 		goto err_exit;
221 	}
222 
223 	retval = pciehp_configure_device(p_slot);
224 	if (retval) {
225 		ctrl_err(ctrl, "Cannot add device at %04x:%02x:00\n",
226 			 pci_domain_nr(parent), parent->number);
227 		goto err_exit;
228 	}
229 
230 	if (PWR_LED(ctrl))
231 		pciehp_green_led_on(p_slot);
232 
233 	return 0;
234 
235 err_exit:
236 	set_slot_off(ctrl, p_slot);
237 	return retval;
238 }
239 
240 /**
241  * remove_board - Turns off slot and LEDs
242  * @p_slot: slot where board is being removed
243  */
244 static int remove_board(struct slot *p_slot)
245 {
246 	int retval = 0;
247 	struct controller *ctrl = p_slot->ctrl;
248 
249 	retval = pciehp_unconfigure_device(p_slot);
250 	if (retval)
251 		return retval;
252 
253 	if (POWER_CTRL(ctrl)) {
254 		/* power off slot */
255 		retval = pciehp_power_off_slot(p_slot);
256 		if (retval) {
257 			ctrl_err(ctrl,
258 				 "Issue of Slot Disable command failed\n");
259 			return retval;
260 		}
261 		/*
262 		 * After turning power off, we must wait for at least 1 second
263 		 * before taking any action that relies on power having been
264 		 * removed from the slot/adapter.
265 		 */
266 		msleep(1000);
267 	}
268 
269 	/* turn off Green LED */
270 	if (PWR_LED(ctrl))
271 		pciehp_green_led_off(p_slot);
272 
273 	return 0;
274 }
275 
276 struct power_work_info {
277 	struct slot *p_slot;
278 	struct work_struct work;
279 };
280 
281 /**
282  * pciehp_power_thread - handle pushbutton events
283  * @work: &struct work_struct describing work to be done
284  *
285  * Scheduled procedure to handle blocking stuff for the pushbuttons.
286  * Handles all pending events and exits.
287  */
288 static void pciehp_power_thread(struct work_struct *work)
289 {
290 	struct power_work_info *info =
291 		container_of(work, struct power_work_info, work);
292 	struct slot *p_slot = info->p_slot;
293 
294 	mutex_lock(&p_slot->lock);
295 	switch (p_slot->state) {
296 	case POWEROFF_STATE:
297 		mutex_unlock(&p_slot->lock);
298 		ctrl_dbg(p_slot->ctrl,
299 			 "Disabling domain:bus:device=%04x:%02x:00\n",
300 			 pci_domain_nr(p_slot->ctrl->pcie->port->subordinate),
301 			 p_slot->ctrl->pcie->port->subordinate->number);
302 		pciehp_disable_slot(p_slot);
303 		mutex_lock(&p_slot->lock);
304 		p_slot->state = STATIC_STATE;
305 		break;
306 	case POWERON_STATE:
307 		mutex_unlock(&p_slot->lock);
308 		if (pciehp_enable_slot(p_slot) && PWR_LED(p_slot->ctrl))
309 			pciehp_green_led_off(p_slot);
310 		mutex_lock(&p_slot->lock);
311 		p_slot->state = STATIC_STATE;
312 		break;
313 	default:
314 		break;
315 	}
316 	mutex_unlock(&p_slot->lock);
317 
318 	kfree(info);
319 }
320 
321 void pciehp_queue_pushbutton_work(struct work_struct *work)
322 {
323 	struct slot *p_slot = container_of(work, struct slot, work.work);
324 	struct power_work_info *info;
325 
326 	info = kmalloc(sizeof(*info), GFP_KERNEL);
327 	if (!info) {
328 		ctrl_err(p_slot->ctrl, "%s: Cannot allocate memory\n",
329 			 __func__);
330 		return;
331 	}
332 	info->p_slot = p_slot;
333 	INIT_WORK(&info->work, pciehp_power_thread);
334 
335 	mutex_lock(&p_slot->lock);
336 	switch (p_slot->state) {
337 	case BLINKINGOFF_STATE:
338 		p_slot->state = POWEROFF_STATE;
339 		break;
340 	case BLINKINGON_STATE:
341 		p_slot->state = POWERON_STATE;
342 		break;
343 	default:
344 		kfree(info);
345 		goto out;
346 	}
347 	queue_work(p_slot->wq, &info->work);
348  out:
349 	mutex_unlock(&p_slot->lock);
350 }
351 
352 /*
353  * Note: This function must be called with slot->lock held
354  */
355 static void handle_button_press_event(struct slot *p_slot)
356 {
357 	struct controller *ctrl = p_slot->ctrl;
358 	u8 getstatus;
359 
360 	switch (p_slot->state) {
361 	case STATIC_STATE:
362 		pciehp_get_power_status(p_slot, &getstatus);
363 		if (getstatus) {
364 			p_slot->state = BLINKINGOFF_STATE;
365 			ctrl_info(ctrl,
366 				  "PCI slot #%s - powering off due to button "
367 				  "press.\n", slot_name(p_slot));
368 		} else {
369 			p_slot->state = BLINKINGON_STATE;
370 			ctrl_info(ctrl,
371 				  "PCI slot #%s - powering on due to button "
372 				  "press.\n", slot_name(p_slot));
373 		}
374 		/* blink green LED and turn off amber */
375 		if (PWR_LED(ctrl))
376 			pciehp_green_led_blink(p_slot);
377 		if (ATTN_LED(ctrl))
378 			pciehp_set_attention_status(p_slot, 0);
379 
380 		queue_delayed_work(p_slot->wq, &p_slot->work, 5*HZ);
381 		break;
382 	case BLINKINGOFF_STATE:
383 	case BLINKINGON_STATE:
384 		/*
385 		 * Cancel if we are still blinking; this means that we
386 		 * press the attention again before the 5 sec. limit
387 		 * expires to cancel hot-add or hot-remove
388 		 */
389 		ctrl_info(ctrl, "Button cancel on Slot(%s)\n", slot_name(p_slot));
390 		cancel_delayed_work(&p_slot->work);
391 		if (p_slot->state == BLINKINGOFF_STATE) {
392 			if (PWR_LED(ctrl))
393 				pciehp_green_led_on(p_slot);
394 		} else {
395 			if (PWR_LED(ctrl))
396 				pciehp_green_led_off(p_slot);
397 		}
398 		if (ATTN_LED(ctrl))
399 			pciehp_set_attention_status(p_slot, 0);
400 		ctrl_info(ctrl, "PCI slot #%s - action canceled "
401 			  "due to button press\n", slot_name(p_slot));
402 		p_slot->state = STATIC_STATE;
403 		break;
404 	case POWEROFF_STATE:
405 	case POWERON_STATE:
406 		/*
407 		 * Ignore if the slot is on power-on or power-off state;
408 		 * this means that the previous attention button action
409 		 * to hot-add or hot-remove is undergoing
410 		 */
411 		ctrl_info(ctrl, "Button ignore on Slot(%s)\n", slot_name(p_slot));
412 		break;
413 	default:
414 		ctrl_warn(ctrl, "Not a valid state\n");
415 		break;
416 	}
417 }
418 
419 /*
420  * Note: This function must be called with slot->lock held
421  */
422 static void handle_surprise_event(struct slot *p_slot)
423 {
424 	u8 getstatus;
425 	struct power_work_info *info;
426 
427 	info = kmalloc(sizeof(*info), GFP_KERNEL);
428 	if (!info) {
429 		ctrl_err(p_slot->ctrl, "%s: Cannot allocate memory\n",
430 			 __func__);
431 		return;
432 	}
433 	info->p_slot = p_slot;
434 	INIT_WORK(&info->work, pciehp_power_thread);
435 
436 	pciehp_get_adapter_status(p_slot, &getstatus);
437 	if (!getstatus)
438 		p_slot->state = POWEROFF_STATE;
439 	else
440 		p_slot->state = POWERON_STATE;
441 
442 	queue_work(p_slot->wq, &info->work);
443 }
444 
445 static void interrupt_event_handler(struct work_struct *work)
446 {
447 	struct event_info *info = container_of(work, struct event_info, work);
448 	struct slot *p_slot = info->p_slot;
449 	struct controller *ctrl = p_slot->ctrl;
450 
451 	mutex_lock(&p_slot->lock);
452 	switch (info->event_type) {
453 	case INT_BUTTON_PRESS:
454 		handle_button_press_event(p_slot);
455 		break;
456 	case INT_POWER_FAULT:
457 		if (!POWER_CTRL(ctrl))
458 			break;
459 		if (ATTN_LED(ctrl))
460 			pciehp_set_attention_status(p_slot, 1);
461 		if (PWR_LED(ctrl))
462 			pciehp_green_led_off(p_slot);
463 		break;
464 	case INT_PRESENCE_ON:
465 	case INT_PRESENCE_OFF:
466 		if (!HP_SUPR_RM(ctrl))
467 			break;
468 		ctrl_dbg(ctrl, "Surprise Removal\n");
469 		handle_surprise_event(p_slot);
470 		break;
471 	default:
472 		break;
473 	}
474 	mutex_unlock(&p_slot->lock);
475 
476 	kfree(info);
477 }
478 
479 int pciehp_enable_slot(struct slot *p_slot)
480 {
481 	u8 getstatus = 0;
482 	int rc;
483 	struct controller *ctrl = p_slot->ctrl;
484 
485 	rc = pciehp_get_adapter_status(p_slot, &getstatus);
486 	if (rc || !getstatus) {
487 		ctrl_info(ctrl, "No adapter on slot(%s)\n", slot_name(p_slot));
488 		return -ENODEV;
489 	}
490 	if (MRL_SENS(p_slot->ctrl)) {
491 		rc = pciehp_get_latch_status(p_slot, &getstatus);
492 		if (rc || getstatus) {
493 			ctrl_info(ctrl, "Latch open on slot(%s)\n",
494 				  slot_name(p_slot));
495 			return -ENODEV;
496 		}
497 	}
498 
499 	if (POWER_CTRL(p_slot->ctrl)) {
500 		rc = pciehp_get_power_status(p_slot, &getstatus);
501 		if (rc || getstatus) {
502 			ctrl_info(ctrl, "Already enabled on slot(%s)\n",
503 				  slot_name(p_slot));
504 			return -EINVAL;
505 		}
506 	}
507 
508 	pciehp_get_latch_status(p_slot, &getstatus);
509 
510 	rc = board_added(p_slot);
511 	if (rc) {
512 		pciehp_get_latch_status(p_slot, &getstatus);
513 	}
514 	return rc;
515 }
516 
517 
518 int pciehp_disable_slot(struct slot *p_slot)
519 {
520 	u8 getstatus = 0;
521 	int ret = 0;
522 	struct controller *ctrl = p_slot->ctrl;
523 
524 	if (!p_slot->ctrl)
525 		return 1;
526 
527 	if (!HP_SUPR_RM(p_slot->ctrl)) {
528 		ret = pciehp_get_adapter_status(p_slot, &getstatus);
529 		if (ret || !getstatus) {
530 			ctrl_info(ctrl, "No adapter on slot(%s)\n",
531 				  slot_name(p_slot));
532 			return -ENODEV;
533 		}
534 	}
535 
536 	if (MRL_SENS(p_slot->ctrl)) {
537 		ret = pciehp_get_latch_status(p_slot, &getstatus);
538 		if (ret || getstatus) {
539 			ctrl_info(ctrl, "Latch open on slot(%s)\n",
540 				  slot_name(p_slot));
541 			return -ENODEV;
542 		}
543 	}
544 
545 	if (POWER_CTRL(p_slot->ctrl)) {
546 		ret = pciehp_get_power_status(p_slot, &getstatus);
547 		if (ret || !getstatus) {
548 			ctrl_info(ctrl, "Already disabled on slot(%s)\n",
549 				  slot_name(p_slot));
550 			return -EINVAL;
551 		}
552 	}
553 
554 	return remove_board(p_slot);
555 }
556 
557 int pciehp_sysfs_enable_slot(struct slot *p_slot)
558 {
559 	int retval = -ENODEV;
560 	struct controller *ctrl = p_slot->ctrl;
561 
562 	mutex_lock(&p_slot->lock);
563 	switch (p_slot->state) {
564 	case BLINKINGON_STATE:
565 		cancel_delayed_work(&p_slot->work);
566 	case STATIC_STATE:
567 		p_slot->state = POWERON_STATE;
568 		mutex_unlock(&p_slot->lock);
569 		retval = pciehp_enable_slot(p_slot);
570 		mutex_lock(&p_slot->lock);
571 		p_slot->state = STATIC_STATE;
572 		break;
573 	case POWERON_STATE:
574 		ctrl_info(ctrl, "Slot %s is already in powering on state\n",
575 			  slot_name(p_slot));
576 		break;
577 	case BLINKINGOFF_STATE:
578 	case POWEROFF_STATE:
579 		ctrl_info(ctrl, "Already enabled on slot %s\n",
580 			  slot_name(p_slot));
581 		break;
582 	default:
583 		ctrl_err(ctrl, "Not a valid state on slot %s\n",
584 			 slot_name(p_slot));
585 		break;
586 	}
587 	mutex_unlock(&p_slot->lock);
588 
589 	return retval;
590 }
591 
592 int pciehp_sysfs_disable_slot(struct slot *p_slot)
593 {
594 	int retval = -ENODEV;
595 	struct controller *ctrl = p_slot->ctrl;
596 
597 	mutex_lock(&p_slot->lock);
598 	switch (p_slot->state) {
599 	case BLINKINGOFF_STATE:
600 		cancel_delayed_work(&p_slot->work);
601 	case STATIC_STATE:
602 		p_slot->state = POWEROFF_STATE;
603 		mutex_unlock(&p_slot->lock);
604 		retval = pciehp_disable_slot(p_slot);
605 		mutex_lock(&p_slot->lock);
606 		p_slot->state = STATIC_STATE;
607 		break;
608 	case POWEROFF_STATE:
609 		ctrl_info(ctrl, "Slot %s is already in powering off state\n",
610 			  slot_name(p_slot));
611 		break;
612 	case BLINKINGON_STATE:
613 	case POWERON_STATE:
614 		ctrl_info(ctrl, "Already disabled on slot %s\n",
615 			  slot_name(p_slot));
616 		break;
617 	default:
618 		ctrl_err(ctrl, "Not a valid state on slot %s\n",
619 			 slot_name(p_slot));
620 		break;
621 	}
622 	mutex_unlock(&p_slot->lock);
623 
624 	return retval;
625 }
626