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/moduleparam.h>
32 #include <linux/kernel.h>
33 #include <linux/types.h>
34 #include <linux/pci.h>
35 #include "pciehp.h"
36 #include <linux/interrupt.h>
37 #include <linux/time.h>
38 
39 /* Global variables */
40 int pciehp_debug;
41 int pciehp_poll_mode;
42 int pciehp_poll_time;
43 int pciehp_force;
44 struct workqueue_struct *pciehp_wq;
45 
46 #define DRIVER_VERSION	"0.4"
47 #define DRIVER_AUTHOR	"Dan Zink <dan.zink@compaq.com>, Greg Kroah-Hartman <greg@kroah.com>, Dely Sy <dely.l.sy@intel.com>"
48 #define DRIVER_DESC	"PCI Express Hot Plug Controller Driver"
49 
50 MODULE_AUTHOR(DRIVER_AUTHOR);
51 MODULE_DESCRIPTION(DRIVER_DESC);
52 MODULE_LICENSE("GPL");
53 
54 module_param(pciehp_debug, bool, 0644);
55 module_param(pciehp_poll_mode, bool, 0644);
56 module_param(pciehp_poll_time, int, 0644);
57 module_param(pciehp_force, bool, 0644);
58 MODULE_PARM_DESC(pciehp_debug, "Debugging mode enabled or not");
59 MODULE_PARM_DESC(pciehp_poll_mode, "Using polling mechanism for hot-plug events or not");
60 MODULE_PARM_DESC(pciehp_poll_time, "Polling mechanism frequency, in seconds");
61 MODULE_PARM_DESC(pciehp_force, "Force pciehp, even if _OSC and OSHP are missing");
62 
63 #define PCIE_MODULE_NAME "pciehp"
64 
65 static int set_attention_status (struct hotplug_slot *slot, u8 value);
66 static int enable_slot		(struct hotplug_slot *slot);
67 static int disable_slot		(struct hotplug_slot *slot);
68 static int get_power_status	(struct hotplug_slot *slot, u8 *value);
69 static int get_attention_status	(struct hotplug_slot *slot, u8 *value);
70 static int get_latch_status	(struct hotplug_slot *slot, u8 *value);
71 static int get_adapter_status	(struct hotplug_slot *slot, u8 *value);
72 static int get_address		(struct hotplug_slot *slot, u32 *value);
73 static int get_max_bus_speed	(struct hotplug_slot *slot, enum pci_bus_speed *value);
74 static int get_cur_bus_speed	(struct hotplug_slot *slot, enum pci_bus_speed *value);
75 
76 static struct hotplug_slot_ops pciehp_hotplug_slot_ops = {
77 	.owner =		THIS_MODULE,
78 	.set_attention_status =	set_attention_status,
79 	.enable_slot =		enable_slot,
80 	.disable_slot =		disable_slot,
81 	.get_power_status =	get_power_status,
82 	.get_attention_status =	get_attention_status,
83 	.get_latch_status =	get_latch_status,
84 	.get_adapter_status =	get_adapter_status,
85 	.get_address =		get_address,
86   	.get_max_bus_speed =	get_max_bus_speed,
87   	.get_cur_bus_speed =	get_cur_bus_speed,
88 };
89 
90 /*
91  * Check the status of the Electro Mechanical Interlock (EMI)
92  */
93 static int get_lock_status(struct hotplug_slot *hotplug_slot, u8 *value)
94 {
95 	struct slot *slot = hotplug_slot->private;
96 	return (slot->hpc_ops->get_emi_status(slot, value));
97 }
98 
99 /*
100  * sysfs interface for the Electro Mechanical Interlock (EMI)
101  * 1 == locked, 0 == unlocked
102  */
103 static ssize_t lock_read_file(struct hotplug_slot *slot, char *buf)
104 {
105 	int retval;
106 	u8 value;
107 
108 	retval = get_lock_status(slot, &value);
109 	if (retval)
110 		goto lock_read_exit;
111 	retval = sprintf (buf, "%d\n", value);
112 
113 lock_read_exit:
114 	return retval;
115 }
116 
117 /*
118  * Change the status of the Electro Mechanical Interlock (EMI)
119  * This is a toggle - in addition there must be at least 1 second
120  * in between toggles.
121  */
122 static int set_lock_status(struct hotplug_slot *hotplug_slot, u8 status)
123 {
124 	struct slot *slot = hotplug_slot->private;
125 	int retval;
126 	u8 value;
127 
128 	mutex_lock(&slot->ctrl->crit_sect);
129 
130 	/* has it been >1 sec since our last toggle? */
131 	if ((get_seconds() - slot->last_emi_toggle) < 1)
132 		return -EINVAL;
133 
134 	/* see what our current state is */
135 	retval = get_lock_status(hotplug_slot, &value);
136 	if (retval || (value == status))
137 		goto set_lock_exit;
138 
139 	slot->hpc_ops->toggle_emi(slot);
140 set_lock_exit:
141 	mutex_unlock(&slot->ctrl->crit_sect);
142 	return 0;
143 }
144 
145 /*
146  * sysfs interface which allows the user to toggle the Electro Mechanical
147  * Interlock.  Valid values are either 0 or 1.  0 == unlock, 1 == lock
148  */
149 static ssize_t lock_write_file(struct hotplug_slot *slot, const char *buf,
150 		size_t count)
151 {
152 	unsigned long llock;
153 	u8 lock;
154 	int retval = 0;
155 
156 	llock = simple_strtoul(buf, NULL, 10);
157 	lock = (u8)(llock & 0xff);
158 
159 	switch (lock) {
160 		case 0:
161 		case 1:
162 			retval = set_lock_status(slot, lock);
163 			break;
164 		default:
165 			err ("%d is an invalid lock value\n", lock);
166 			retval = -EINVAL;
167 	}
168 	if (retval)
169 		return retval;
170 	return count;
171 }
172 
173 static struct hotplug_slot_attribute hotplug_slot_attr_lock = {
174 	.attr = {.name = "lock", .mode = S_IFREG | S_IRUGO | S_IWUSR},
175 	.show = lock_read_file,
176 	.store = lock_write_file
177 };
178 
179 /**
180  * release_slot - free up the memory used by a slot
181  * @hotplug_slot: slot to free
182  */
183 static void release_slot(struct hotplug_slot *hotplug_slot)
184 {
185 	struct slot *slot = hotplug_slot->private;
186 
187 	dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
188 
189 	kfree(slot->hotplug_slot->info);
190 	kfree(slot->hotplug_slot);
191 	kfree(slot);
192 }
193 
194 static void make_slot_name(struct slot *slot)
195 {
196 	snprintf(slot->hotplug_slot->name, SLOT_NAME_SIZE, "%04d_%04d",
197 		 slot->bus, slot->number);
198 }
199 
200 static int init_slots(struct controller *ctrl)
201 {
202 	struct slot *slot;
203 	struct hotplug_slot *hotplug_slot;
204 	struct hotplug_slot_info *info;
205 	int retval = -ENOMEM;
206 	int i;
207 
208 	for (i = 0; i < ctrl->num_slots; i++) {
209 		slot = kzalloc(sizeof(*slot), GFP_KERNEL);
210 		if (!slot)
211 			goto error;
212 
213 		hotplug_slot = kzalloc(sizeof(*hotplug_slot), GFP_KERNEL);
214 		if (!hotplug_slot)
215 			goto error_slot;
216 		slot->hotplug_slot = hotplug_slot;
217 
218 		info = kzalloc(sizeof(*info), GFP_KERNEL);
219 		if (!info)
220 			goto error_hpslot;
221 		hotplug_slot->info = info;
222 
223 		hotplug_slot->name = slot->name;
224 
225 		slot->hp_slot = i;
226 		slot->ctrl = ctrl;
227 		slot->bus = ctrl->pci_dev->subordinate->number;
228 		slot->device = ctrl->slot_device_offset + i;
229 		slot->hpc_ops = ctrl->hpc_ops;
230 		slot->number = ctrl->first_slot;
231 		mutex_init(&slot->lock);
232 		INIT_DELAYED_WORK(&slot->work, pciehp_queue_pushbutton_work);
233 
234 		/* register this slot with the hotplug pci core */
235 		hotplug_slot->private = slot;
236 		hotplug_slot->release = &release_slot;
237 		make_slot_name(slot);
238 		hotplug_slot->ops = &pciehp_hotplug_slot_ops;
239 
240 		get_power_status(hotplug_slot, &info->power_status);
241 		get_attention_status(hotplug_slot, &info->attention_status);
242 		get_latch_status(hotplug_slot, &info->latch_status);
243 		get_adapter_status(hotplug_slot, &info->adapter_status);
244 
245 		dbg("Registering bus=%x dev=%x hp_slot=%x sun=%x "
246 		    "slot_device_offset=%x\n", slot->bus, slot->device,
247 		    slot->hp_slot, slot->number, ctrl->slot_device_offset);
248 		retval = pci_hp_register(hotplug_slot);
249 		if (retval) {
250 			err ("pci_hp_register failed with error %d\n", retval);
251 			goto error_info;
252 		}
253 		/* create additional sysfs entries */
254 		if (EMI(ctrl->ctrlcap)) {
255 			retval = sysfs_create_file(&hotplug_slot->kobj,
256 				&hotplug_slot_attr_lock.attr);
257 			if (retval) {
258 				pci_hp_deregister(hotplug_slot);
259 				err("cannot create additional sysfs entries\n");
260 				goto error_info;
261 			}
262 		}
263 
264 		list_add(&slot->slot_list, &ctrl->slot_list);
265 	}
266 
267 	return 0;
268 error_info:
269 	kfree(info);
270 error_hpslot:
271 	kfree(hotplug_slot);
272 error_slot:
273 	kfree(slot);
274 error:
275 	return retval;
276 }
277 
278 static void cleanup_slots(struct controller *ctrl)
279 {
280 	struct list_head *tmp;
281 	struct list_head *next;
282 	struct slot *slot;
283 
284 	list_for_each_safe(tmp, next, &ctrl->slot_list) {
285 		slot = list_entry(tmp, struct slot, slot_list);
286 		list_del(&slot->slot_list);
287 		if (EMI(ctrl->ctrlcap))
288 			sysfs_remove_file(&slot->hotplug_slot->kobj,
289 				&hotplug_slot_attr_lock.attr);
290 		cancel_delayed_work(&slot->work);
291 		flush_scheduled_work();
292 		flush_workqueue(pciehp_wq);
293 		pci_hp_deregister(slot->hotplug_slot);
294 	}
295 }
296 
297 /*
298  * set_attention_status - Turns the Amber LED for a slot on, off or blink
299  */
300 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
301 {
302 	struct slot *slot = hotplug_slot->private;
303 
304 	dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
305 
306 	hotplug_slot->info->attention_status = status;
307 
308 	if (ATTN_LED(slot->ctrl->ctrlcap))
309 		slot->hpc_ops->set_attention_status(slot, status);
310 
311 	return 0;
312 }
313 
314 
315 static int enable_slot(struct hotplug_slot *hotplug_slot)
316 {
317 	struct slot *slot = hotplug_slot->private;
318 
319 	dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
320 
321 	return pciehp_sysfs_enable_slot(slot);
322 }
323 
324 
325 static int disable_slot(struct hotplug_slot *hotplug_slot)
326 {
327 	struct slot *slot = hotplug_slot->private;
328 
329 	dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
330 
331 	return pciehp_sysfs_disable_slot(slot);
332 }
333 
334 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
335 {
336 	struct slot *slot = hotplug_slot->private;
337 	int retval;
338 
339 	dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
340 
341 	retval = slot->hpc_ops->get_power_status(slot, value);
342 	if (retval < 0)
343 		*value = hotplug_slot->info->power_status;
344 
345 	return 0;
346 }
347 
348 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
349 {
350 	struct slot *slot = hotplug_slot->private;
351 	int retval;
352 
353 	dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
354 
355 	retval = slot->hpc_ops->get_attention_status(slot, value);
356 	if (retval < 0)
357 		*value = hotplug_slot->info->attention_status;
358 
359 	return 0;
360 }
361 
362 static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
363 {
364 	struct slot *slot = hotplug_slot->private;
365 	int retval;
366 
367 	dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
368 
369 	retval = slot->hpc_ops->get_latch_status(slot, value);
370 	if (retval < 0)
371 		*value = hotplug_slot->info->latch_status;
372 
373 	return 0;
374 }
375 
376 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
377 {
378 	struct slot *slot = hotplug_slot->private;
379 	int retval;
380 
381 	dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
382 
383 	retval = slot->hpc_ops->get_adapter_status(slot, value);
384 	if (retval < 0)
385 		*value = hotplug_slot->info->adapter_status;
386 
387 	return 0;
388 }
389 
390 static int get_address(struct hotplug_slot *hotplug_slot, u32 *value)
391 {
392 	struct slot *slot = hotplug_slot->private;
393 	struct pci_bus *bus = slot->ctrl->pci_dev->subordinate;
394 
395 	dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
396 
397 	*value = (pci_domain_nr(bus) << 16) | (slot->bus << 8) | slot->device;
398 
399 	return 0;
400 }
401 
402 static int get_max_bus_speed(struct hotplug_slot *hotplug_slot, enum pci_bus_speed *value)
403 {
404 	struct slot *slot = hotplug_slot->private;
405 	int retval;
406 
407 	dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
408 
409 	retval = slot->hpc_ops->get_max_bus_speed(slot, value);
410 	if (retval < 0)
411 		*value = PCI_SPEED_UNKNOWN;
412 
413 	return 0;
414 }
415 
416 static int get_cur_bus_speed(struct hotplug_slot *hotplug_slot, enum pci_bus_speed *value)
417 {
418 	struct slot *slot = hotplug_slot->private;
419 	int retval;
420 
421 	dbg("%s - physical_slot = %s\n", __FUNCTION__, hotplug_slot->name);
422 
423 	retval = slot->hpc_ops->get_cur_bus_speed(slot, value);
424 	if (retval < 0)
425 		*value = PCI_SPEED_UNKNOWN;
426 
427 	return 0;
428 }
429 
430 static int pciehp_probe(struct pcie_device *dev, const struct pcie_port_service_id *id)
431 {
432 	int rc;
433 	struct controller *ctrl;
434 	struct slot *t_slot;
435 	u8 value;
436 	struct pci_dev *pdev;
437 
438 	ctrl = kzalloc(sizeof(*ctrl), GFP_KERNEL);
439 	if (!ctrl) {
440 		err("%s : out of memory\n", __FUNCTION__);
441 		goto err_out_none;
442 	}
443 	INIT_LIST_HEAD(&ctrl->slot_list);
444 
445 	pdev = dev->port;
446 	ctrl->pci_dev = pdev;
447 
448 	rc = pcie_init(ctrl, dev);
449 	if (rc) {
450 		dbg("%s: controller initialization failed\n", PCIE_MODULE_NAME);
451 		goto err_out_free_ctrl;
452 	}
453 
454 	pci_set_drvdata(pdev, ctrl);
455 
456 	dbg("%s: ctrl bus=0x%x, device=%x, function=%x, irq=%x\n",
457 	    __FUNCTION__, pdev->bus->number, PCI_SLOT(pdev->devfn),
458 	    PCI_FUNC(pdev->devfn), pdev->irq);
459 
460 	/* Setup the slot information structures */
461 	rc = init_slots(ctrl);
462 	if (rc) {
463 		err("%s: slot initialization failed\n", PCIE_MODULE_NAME);
464 		goto err_out_release_ctlr;
465 	}
466 
467 	t_slot = pciehp_find_slot(ctrl, ctrl->slot_device_offset);
468 
469 	t_slot->hpc_ops->get_adapter_status(t_slot, &value); /* Check if slot is occupied */
470 	if (value && pciehp_force) {
471 		rc = pciehp_enable_slot(t_slot);
472 		if (rc)	/* -ENODEV: shouldn't happen, but deal with it */
473 			value = 0;
474 	}
475 	if ((POWER_CTRL(ctrl->ctrlcap)) && !value) {
476 		rc = t_slot->hpc_ops->power_off_slot(t_slot); /* Power off slot if not occupied*/
477 		if (rc)
478 			goto err_out_free_ctrl_slot;
479 	}
480 
481 	return 0;
482 
483 err_out_free_ctrl_slot:
484 	cleanup_slots(ctrl);
485 err_out_release_ctlr:
486 	ctrl->hpc_ops->release_ctlr(ctrl);
487 err_out_free_ctrl:
488 	kfree(ctrl);
489 err_out_none:
490 	return -ENODEV;
491 }
492 
493 static void pciehp_remove (struct pcie_device *dev)
494 {
495 	struct pci_dev *pdev = dev->port;
496 	struct controller *ctrl = pci_get_drvdata(pdev);
497 
498 	cleanup_slots(ctrl);
499 	ctrl->hpc_ops->release_ctlr(ctrl);
500 	kfree(ctrl);
501 }
502 
503 #ifdef CONFIG_PM
504 static int pciehp_suspend (struct pcie_device *dev, pm_message_t state)
505 {
506 	printk("%s ENTRY\n", __FUNCTION__);
507 	return 0;
508 }
509 
510 static int pciehp_resume (struct pcie_device *dev)
511 {
512 	printk("%s ENTRY\n", __FUNCTION__);
513 	if (pciehp_force) {
514 		struct pci_dev *pdev = dev->port;
515 		struct controller *ctrl = pci_get_drvdata(pdev);
516 		struct slot *t_slot;
517 		u8 status;
518 
519 		/* reinitialize the chipset's event detection logic */
520 		pcie_init_hardware_part2(ctrl, dev);
521 
522 		t_slot = pciehp_find_slot(ctrl, ctrl->slot_device_offset);
523 
524 		/* Check if slot is occupied */
525 		t_slot->hpc_ops->get_adapter_status(t_slot, &status);
526 		if (status)
527 			pciehp_enable_slot(t_slot);
528 		else
529 			pciehp_disable_slot(t_slot);
530 	}
531 	return 0;
532 }
533 #endif
534 
535 static struct pcie_port_service_id port_pci_ids[] = { {
536 	.vendor = PCI_ANY_ID,
537 	.device = PCI_ANY_ID,
538 	.port_type = PCIE_ANY_PORT,
539 	.service_type = PCIE_PORT_SERVICE_HP,
540 	.driver_data =	0,
541 	}, { /* end: all zeroes */ }
542 };
543 static const char device_name[] = "hpdriver";
544 
545 static struct pcie_port_service_driver hpdriver_portdrv = {
546 	.name		= (char *)device_name,
547 	.id_table	= &port_pci_ids[0],
548 
549 	.probe		= pciehp_probe,
550 	.remove		= pciehp_remove,
551 
552 #ifdef	CONFIG_PM
553 	.suspend	= pciehp_suspend,
554 	.resume		= pciehp_resume,
555 #endif	/* PM */
556 };
557 
558 static int __init pcied_init(void)
559 {
560 	int retval = 0;
561 
562 	retval = pcie_port_service_register(&hpdriver_portdrv);
563  	dbg("pcie_port_service_register = %d\n", retval);
564   	info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
565  	if (retval)
566 		dbg("%s: Failure to register service\n", __FUNCTION__);
567 	return retval;
568 }
569 
570 static void __exit pcied_cleanup(void)
571 {
572 	dbg("unload_pciehpd()\n");
573 	pcie_port_service_unregister(&hpdriver_portdrv);
574 	info(DRIVER_DESC " version: " DRIVER_VERSION " unloaded\n");
575 }
576 
577 module_init(pcied_init);
578 module_exit(pcied_cleanup);
579