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 	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 		goto out;
345 	}
346 	queue_work(pciehp_wq, &info->work);
347  out:
348 	mutex_unlock(&p_slot->lock);
349 }
350 
351 /*
352  * Note: This function must be called with slot->lock held
353  */
354 static void handle_button_press_event(struct slot *p_slot)
355 {
356 	struct controller *ctrl = p_slot->ctrl;
357 	u8 getstatus;
358 
359 	switch (p_slot->state) {
360 	case STATIC_STATE:
361 		pciehp_get_power_status(p_slot, &getstatus);
362 		if (getstatus) {
363 			p_slot->state = BLINKINGOFF_STATE;
364 			ctrl_info(ctrl,
365 				  "PCI slot #%s - powering off due to button "
366 				  "press.\n", slot_name(p_slot));
367 		} else {
368 			p_slot->state = BLINKINGON_STATE;
369 			ctrl_info(ctrl,
370 				  "PCI slot #%s - powering on due to button "
371 				  "press.\n", slot_name(p_slot));
372 		}
373 		/* blink green LED and turn off amber */
374 		if (PWR_LED(ctrl))
375 			pciehp_green_led_blink(p_slot);
376 		if (ATTN_LED(ctrl))
377 			pciehp_set_attention_status(p_slot, 0);
378 
379 		schedule_delayed_work(&p_slot->work, 5*HZ);
380 		break;
381 	case BLINKINGOFF_STATE:
382 	case BLINKINGON_STATE:
383 		/*
384 		 * Cancel if we are still blinking; this means that we
385 		 * press the attention again before the 5 sec. limit
386 		 * expires to cancel hot-add or hot-remove
387 		 */
388 		ctrl_info(ctrl, "Button cancel on Slot(%s)\n", slot_name(p_slot));
389 		cancel_delayed_work(&p_slot->work);
390 		if (p_slot->state == BLINKINGOFF_STATE) {
391 			if (PWR_LED(ctrl))
392 				pciehp_green_led_on(p_slot);
393 		} else {
394 			if (PWR_LED(ctrl))
395 				pciehp_green_led_off(p_slot);
396 		}
397 		if (ATTN_LED(ctrl))
398 			pciehp_set_attention_status(p_slot, 0);
399 		ctrl_info(ctrl, "PCI slot #%s - action canceled "
400 			  "due to button press\n", slot_name(p_slot));
401 		p_slot->state = STATIC_STATE;
402 		break;
403 	case POWEROFF_STATE:
404 	case POWERON_STATE:
405 		/*
406 		 * Ignore if the slot is on power-on or power-off state;
407 		 * this means that the previous attention button action
408 		 * to hot-add or hot-remove is undergoing
409 		 */
410 		ctrl_info(ctrl, "Button ignore on Slot(%s)\n", slot_name(p_slot));
411 		break;
412 	default:
413 		ctrl_warn(ctrl, "Not a valid state\n");
414 		break;
415 	}
416 }
417 
418 /*
419  * Note: This function must be called with slot->lock held
420  */
421 static void handle_surprise_event(struct slot *p_slot)
422 {
423 	u8 getstatus;
424 	struct power_work_info *info;
425 
426 	info = kmalloc(sizeof(*info), GFP_KERNEL);
427 	if (!info) {
428 		ctrl_err(p_slot->ctrl, "%s: Cannot allocate memory\n",
429 			 __func__);
430 		return;
431 	}
432 	info->p_slot = p_slot;
433 	INIT_WORK(&info->work, pciehp_power_thread);
434 
435 	pciehp_get_adapter_status(p_slot, &getstatus);
436 	if (!getstatus)
437 		p_slot->state = POWEROFF_STATE;
438 	else
439 		p_slot->state = POWERON_STATE;
440 
441 	queue_work(pciehp_wq, &info->work);
442 }
443 
444 static void interrupt_event_handler(struct work_struct *work)
445 {
446 	struct event_info *info = container_of(work, struct event_info, work);
447 	struct slot *p_slot = info->p_slot;
448 	struct controller *ctrl = p_slot->ctrl;
449 
450 	mutex_lock(&p_slot->lock);
451 	switch (info->event_type) {
452 	case INT_BUTTON_PRESS:
453 		handle_button_press_event(p_slot);
454 		break;
455 	case INT_POWER_FAULT:
456 		if (!POWER_CTRL(ctrl))
457 			break;
458 		if (ATTN_LED(ctrl))
459 			pciehp_set_attention_status(p_slot, 1);
460 		if (PWR_LED(ctrl))
461 			pciehp_green_led_off(p_slot);
462 		break;
463 	case INT_PRESENCE_ON:
464 	case INT_PRESENCE_OFF:
465 		if (!HP_SUPR_RM(ctrl))
466 			break;
467 		ctrl_dbg(ctrl, "Surprise Removal\n");
468 		handle_surprise_event(p_slot);
469 		break;
470 	default:
471 		break;
472 	}
473 	mutex_unlock(&p_slot->lock);
474 
475 	kfree(info);
476 }
477 
478 int pciehp_enable_slot(struct slot *p_slot)
479 {
480 	u8 getstatus = 0;
481 	int rc;
482 	struct controller *ctrl = p_slot->ctrl;
483 
484 	rc = pciehp_get_adapter_status(p_slot, &getstatus);
485 	if (rc || !getstatus) {
486 		ctrl_info(ctrl, "No adapter on slot(%s)\n", slot_name(p_slot));
487 		return -ENODEV;
488 	}
489 	if (MRL_SENS(p_slot->ctrl)) {
490 		rc = pciehp_get_latch_status(p_slot, &getstatus);
491 		if (rc || getstatus) {
492 			ctrl_info(ctrl, "Latch open on slot(%s)\n",
493 				  slot_name(p_slot));
494 			return -ENODEV;
495 		}
496 	}
497 
498 	if (POWER_CTRL(p_slot->ctrl)) {
499 		rc = pciehp_get_power_status(p_slot, &getstatus);
500 		if (rc || getstatus) {
501 			ctrl_info(ctrl, "Already enabled on slot(%s)\n",
502 				  slot_name(p_slot));
503 			return -EINVAL;
504 		}
505 	}
506 
507 	pciehp_get_latch_status(p_slot, &getstatus);
508 
509 	rc = board_added(p_slot);
510 	if (rc) {
511 		pciehp_get_latch_status(p_slot, &getstatus);
512 	}
513 	return rc;
514 }
515 
516 
517 int pciehp_disable_slot(struct slot *p_slot)
518 {
519 	u8 getstatus = 0;
520 	int ret = 0;
521 	struct controller *ctrl = p_slot->ctrl;
522 
523 	if (!p_slot->ctrl)
524 		return 1;
525 
526 	if (!HP_SUPR_RM(p_slot->ctrl)) {
527 		ret = pciehp_get_adapter_status(p_slot, &getstatus);
528 		if (ret || !getstatus) {
529 			ctrl_info(ctrl, "No adapter on slot(%s)\n",
530 				  slot_name(p_slot));
531 			return -ENODEV;
532 		}
533 	}
534 
535 	if (MRL_SENS(p_slot->ctrl)) {
536 		ret = pciehp_get_latch_status(p_slot, &getstatus);
537 		if (ret || getstatus) {
538 			ctrl_info(ctrl, "Latch open on slot(%s)\n",
539 				  slot_name(p_slot));
540 			return -ENODEV;
541 		}
542 	}
543 
544 	if (POWER_CTRL(p_slot->ctrl)) {
545 		ret = pciehp_get_power_status(p_slot, &getstatus);
546 		if (ret || !getstatus) {
547 			ctrl_info(ctrl, "Already disabled on slot(%s)\n",
548 				  slot_name(p_slot));
549 			return -EINVAL;
550 		}
551 	}
552 
553 	return remove_board(p_slot);
554 }
555 
556 int pciehp_sysfs_enable_slot(struct slot *p_slot)
557 {
558 	int retval = -ENODEV;
559 	struct controller *ctrl = p_slot->ctrl;
560 
561 	mutex_lock(&p_slot->lock);
562 	switch (p_slot->state) {
563 	case BLINKINGON_STATE:
564 		cancel_delayed_work(&p_slot->work);
565 	case STATIC_STATE:
566 		p_slot->state = POWERON_STATE;
567 		mutex_unlock(&p_slot->lock);
568 		retval = pciehp_enable_slot(p_slot);
569 		mutex_lock(&p_slot->lock);
570 		p_slot->state = STATIC_STATE;
571 		break;
572 	case POWERON_STATE:
573 		ctrl_info(ctrl, "Slot %s is already in powering on state\n",
574 			  slot_name(p_slot));
575 		break;
576 	case BLINKINGOFF_STATE:
577 	case POWEROFF_STATE:
578 		ctrl_info(ctrl, "Already enabled on slot %s\n",
579 			  slot_name(p_slot));
580 		break;
581 	default:
582 		ctrl_err(ctrl, "Not a valid state on slot %s\n",
583 			 slot_name(p_slot));
584 		break;
585 	}
586 	mutex_unlock(&p_slot->lock);
587 
588 	return retval;
589 }
590 
591 int pciehp_sysfs_disable_slot(struct slot *p_slot)
592 {
593 	int retval = -ENODEV;
594 	struct controller *ctrl = p_slot->ctrl;
595 
596 	mutex_lock(&p_slot->lock);
597 	switch (p_slot->state) {
598 	case BLINKINGOFF_STATE:
599 		cancel_delayed_work(&p_slot->work);
600 	case STATIC_STATE:
601 		p_slot->state = POWEROFF_STATE;
602 		mutex_unlock(&p_slot->lock);
603 		retval = pciehp_disable_slot(p_slot);
604 		mutex_lock(&p_slot->lock);
605 		p_slot->state = STATIC_STATE;
606 		break;
607 	case POWEROFF_STATE:
608 		ctrl_info(ctrl, "Slot %s is already in powering off state\n",
609 			  slot_name(p_slot));
610 		break;
611 	case BLINKINGON_STATE:
612 	case POWERON_STATE:
613 		ctrl_info(ctrl, "Already disabled on slot %s\n",
614 			  slot_name(p_slot));
615 		break;
616 	default:
617 		ctrl_err(ctrl, "Not a valid state on slot %s\n",
618 			 slot_name(p_slot));
619 		break;
620 	}
621 	mutex_unlock(&p_slot->lock);
622 
623 	return retval;
624 }
625