xref: /linux/drivers/pci/hotplug/pciehp_core.c (revision 367b8112fe2ea5c39a7bb4d263dcdd9b612fae18)
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_max_bus_speed	(struct hotplug_slot *slot, enum pci_bus_speed *value);
73 static int get_cur_bus_speed	(struct hotplug_slot *slot, enum pci_bus_speed *value);
74 
75 static struct hotplug_slot_ops pciehp_hotplug_slot_ops = {
76 	.owner =		THIS_MODULE,
77 	.set_attention_status =	set_attention_status,
78 	.enable_slot =		enable_slot,
79 	.disable_slot =		disable_slot,
80 	.get_power_status =	get_power_status,
81 	.get_attention_status =	get_attention_status,
82 	.get_latch_status =	get_latch_status,
83 	.get_adapter_status =	get_adapter_status,
84   	.get_max_bus_speed =	get_max_bus_speed,
85   	.get_cur_bus_speed =	get_cur_bus_speed,
86 };
87 
88 /*
89  * Check the status of the Electro Mechanical Interlock (EMI)
90  */
91 static int get_lock_status(struct hotplug_slot *hotplug_slot, u8 *value)
92 {
93 	struct slot *slot = hotplug_slot->private;
94 	return (slot->hpc_ops->get_emi_status(slot, value));
95 }
96 
97 /*
98  * sysfs interface for the Electro Mechanical Interlock (EMI)
99  * 1 == locked, 0 == unlocked
100  */
101 static ssize_t lock_read_file(struct hotplug_slot *slot, char *buf)
102 {
103 	int retval;
104 	u8 value;
105 
106 	retval = get_lock_status(slot, &value);
107 	if (retval)
108 		goto lock_read_exit;
109 	retval = sprintf (buf, "%d\n", value);
110 
111 lock_read_exit:
112 	return retval;
113 }
114 
115 /*
116  * Change the status of the Electro Mechanical Interlock (EMI)
117  * This is a toggle - in addition there must be at least 1 second
118  * in between toggles.
119  */
120 static int set_lock_status(struct hotplug_slot *hotplug_slot, u8 status)
121 {
122 	struct slot *slot = hotplug_slot->private;
123 	int retval;
124 	u8 value;
125 
126 	mutex_lock(&slot->ctrl->crit_sect);
127 
128 	/* has it been >1 sec since our last toggle? */
129 	if ((get_seconds() - slot->last_emi_toggle) < 1)
130 		return -EINVAL;
131 
132 	/* see what our current state is */
133 	retval = get_lock_status(hotplug_slot, &value);
134 	if (retval || (value == status))
135 		goto set_lock_exit;
136 
137 	slot->hpc_ops->toggle_emi(slot);
138 set_lock_exit:
139 	mutex_unlock(&slot->ctrl->crit_sect);
140 	return 0;
141 }
142 
143 /*
144  * sysfs interface which allows the user to toggle the Electro Mechanical
145  * Interlock.  Valid values are either 0 or 1.  0 == unlock, 1 == lock
146  */
147 static ssize_t lock_write_file(struct hotplug_slot *hotplug_slot,
148 		const char *buf, size_t count)
149 {
150 	struct slot *slot = hotplug_slot->private;
151 	unsigned long llock;
152 	u8 lock;
153 	int retval = 0;
154 
155 	llock = simple_strtoul(buf, NULL, 10);
156 	lock = (u8)(llock & 0xff);
157 
158 	switch (lock) {
159 		case 0:
160 		case 1:
161 			retval = set_lock_status(hotplug_slot, lock);
162 			break;
163 		default:
164 			ctrl_err(slot->ctrl, "%d is an invalid lock value\n",
165 				 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 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
188 		 __func__, hotplug_slot_name(hotplug_slot));
189 
190 	kfree(hotplug_slot->info);
191 	kfree(hotplug_slot);
192 }
193 
194 static int init_slots(struct controller *ctrl)
195 {
196 	struct slot *slot;
197 	struct hotplug_slot *hotplug_slot;
198 	struct hotplug_slot_info *info;
199 	char name[SLOT_NAME_SIZE];
200 	int retval = -ENOMEM;
201 
202 	list_for_each_entry(slot, &ctrl->slot_list, slot_list) {
203 		hotplug_slot = kzalloc(sizeof(*hotplug_slot), GFP_KERNEL);
204 		if (!hotplug_slot)
205 			goto error;
206 
207 		info = kzalloc(sizeof(*info), GFP_KERNEL);
208 		if (!info)
209 			goto error_hpslot;
210 
211 		/* register this slot with the hotplug pci core */
212 		hotplug_slot->info = info;
213 		hotplug_slot->private = slot;
214 		hotplug_slot->release = &release_slot;
215 		hotplug_slot->ops = &pciehp_hotplug_slot_ops;
216 		slot->hotplug_slot = hotplug_slot;
217 		snprintf(name, SLOT_NAME_SIZE, "%u", slot->number);
218 
219  		ctrl_dbg(ctrl, "Registering domain:bus:dev=%04x:%02x:%02x "
220  			 "hp_slot=%x sun=%x slot_device_offset=%x\n",
221  			 pci_domain_nr(ctrl->pci_dev->subordinate),
222  			 slot->bus, slot->device, slot->hp_slot, slot->number,
223  			 ctrl->slot_device_offset);
224 		retval = pci_hp_register(hotplug_slot,
225 					 ctrl->pci_dev->subordinate,
226 					 slot->device,
227 					 name);
228 		if (retval) {
229 			ctrl_err(ctrl, "pci_hp_register failed with error %d\n",
230 				 retval);
231 			goto error_info;
232 		}
233 		get_power_status(hotplug_slot, &info->power_status);
234 		get_attention_status(hotplug_slot, &info->attention_status);
235 		get_latch_status(hotplug_slot, &info->latch_status);
236 		get_adapter_status(hotplug_slot, &info->adapter_status);
237 		/* create additional sysfs entries */
238 		if (EMI(ctrl)) {
239 			retval = sysfs_create_file(&hotplug_slot->pci_slot->kobj,
240 				&hotplug_slot_attr_lock.attr);
241 			if (retval) {
242 				pci_hp_deregister(hotplug_slot);
243 				ctrl_err(ctrl, "Cannot create additional sysfs "
244 					 "entries\n");
245 				goto error_info;
246 			}
247 		}
248 	}
249 
250 	return 0;
251 error_info:
252 	kfree(info);
253 error_hpslot:
254 	kfree(hotplug_slot);
255 error:
256 	return retval;
257 }
258 
259 static void cleanup_slots(struct controller *ctrl)
260 {
261 	struct slot *slot;
262 
263 	list_for_each_entry(slot, &ctrl->slot_list, slot_list) {
264 		if (EMI(ctrl))
265 			sysfs_remove_file(&slot->hotplug_slot->pci_slot->kobj,
266 				&hotplug_slot_attr_lock.attr);
267 		pci_hp_deregister(slot->hotplug_slot);
268 	}
269 }
270 
271 /*
272  * set_attention_status - Turns the Amber LED for a slot on, off or blink
273  */
274 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
275 {
276 	struct slot *slot = hotplug_slot->private;
277 
278 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
279 		  __func__, slot_name(slot));
280 
281 	hotplug_slot->info->attention_status = status;
282 
283 	if (ATTN_LED(slot->ctrl))
284 		slot->hpc_ops->set_attention_status(slot, status);
285 
286 	return 0;
287 }
288 
289 
290 static int enable_slot(struct hotplug_slot *hotplug_slot)
291 {
292 	struct slot *slot = hotplug_slot->private;
293 
294 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
295 		 __func__, slot_name(slot));
296 
297 	return pciehp_sysfs_enable_slot(slot);
298 }
299 
300 
301 static int disable_slot(struct hotplug_slot *hotplug_slot)
302 {
303 	struct slot *slot = hotplug_slot->private;
304 
305 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
306 		  __func__, slot_name(slot));
307 
308 	return pciehp_sysfs_disable_slot(slot);
309 }
310 
311 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
312 {
313 	struct slot *slot = hotplug_slot->private;
314 	int retval;
315 
316 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
317 		  __func__, slot_name(slot));
318 
319 	retval = slot->hpc_ops->get_power_status(slot, value);
320 	if (retval < 0)
321 		*value = hotplug_slot->info->power_status;
322 
323 	return 0;
324 }
325 
326 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
327 {
328 	struct slot *slot = hotplug_slot->private;
329 	int retval;
330 
331 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
332 		  __func__, slot_name(slot));
333 
334 	retval = slot->hpc_ops->get_attention_status(slot, value);
335 	if (retval < 0)
336 		*value = hotplug_slot->info->attention_status;
337 
338 	return 0;
339 }
340 
341 static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
342 {
343 	struct slot *slot = hotplug_slot->private;
344 	int retval;
345 
346 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
347 		 __func__, slot_name(slot));
348 
349 	retval = slot->hpc_ops->get_latch_status(slot, value);
350 	if (retval < 0)
351 		*value = hotplug_slot->info->latch_status;
352 
353 	return 0;
354 }
355 
356 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
357 {
358 	struct slot *slot = hotplug_slot->private;
359 	int retval;
360 
361 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
362 		 __func__, slot_name(slot));
363 
364 	retval = slot->hpc_ops->get_adapter_status(slot, value);
365 	if (retval < 0)
366 		*value = hotplug_slot->info->adapter_status;
367 
368 	return 0;
369 }
370 
371 static int get_max_bus_speed(struct hotplug_slot *hotplug_slot,
372 				enum pci_bus_speed *value)
373 {
374 	struct slot *slot = hotplug_slot->private;
375 	int retval;
376 
377 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
378 		 __func__, slot_name(slot));
379 
380 	retval = slot->hpc_ops->get_max_bus_speed(slot, value);
381 	if (retval < 0)
382 		*value = PCI_SPEED_UNKNOWN;
383 
384 	return 0;
385 }
386 
387 static int get_cur_bus_speed(struct hotplug_slot *hotplug_slot, enum pci_bus_speed *value)
388 {
389 	struct slot *slot = hotplug_slot->private;
390 	int retval;
391 
392 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
393 		 __func__, slot_name(slot));
394 
395 	retval = slot->hpc_ops->get_cur_bus_speed(slot, value);
396 	if (retval < 0)
397 		*value = PCI_SPEED_UNKNOWN;
398 
399 	return 0;
400 }
401 
402 static int pciehp_probe(struct pcie_device *dev, const struct pcie_port_service_id *id)
403 {
404 	int rc;
405 	struct controller *ctrl;
406 	struct slot *t_slot;
407 	u8 value;
408 	struct pci_dev *pdev = dev->port;
409 
410 	if (pciehp_force)
411 		dev_info(&dev->device,
412 			 "Bypassing BIOS check for pciehp use on %s\n",
413 			 pci_name(pdev));
414 	else if (pciehp_get_hp_hw_control_from_firmware(pdev))
415 		goto err_out_none;
416 
417 	ctrl = pcie_init(dev);
418 	if (!ctrl) {
419 		dev_err(&dev->device, "Controller initialization failed\n");
420 		goto err_out_none;
421 	}
422 	set_service_data(dev, ctrl);
423 
424 	/* Setup the slot information structures */
425 	rc = init_slots(ctrl);
426 	if (rc) {
427 		if (rc == -EBUSY)
428 			ctrl_warn(ctrl, "Slot already registered by another "
429 				  "hotplug driver\n");
430 		else
431 			ctrl_err(ctrl, "Slot initialization failed\n");
432 		goto err_out_release_ctlr;
433 	}
434 
435 	t_slot = pciehp_find_slot(ctrl, ctrl->slot_device_offset);
436 
437 	t_slot->hpc_ops->get_adapter_status(t_slot, &value); /* Check if slot is occupied */
438 	if (value && pciehp_force) {
439 		rc = pciehp_enable_slot(t_slot);
440 		if (rc)	/* -ENODEV: shouldn't happen, but deal with it */
441 			value = 0;
442 	}
443 	if ((POWER_CTRL(ctrl)) && !value) {
444 		rc = t_slot->hpc_ops->power_off_slot(t_slot); /* Power off slot if not occupied*/
445 		if (rc)
446 			goto err_out_free_ctrl_slot;
447 	}
448 
449 	return 0;
450 
451 err_out_free_ctrl_slot:
452 	cleanup_slots(ctrl);
453 err_out_release_ctlr:
454 	ctrl->hpc_ops->release_ctlr(ctrl);
455 err_out_none:
456 	return -ENODEV;
457 }
458 
459 static void pciehp_remove (struct pcie_device *dev)
460 {
461 	struct controller *ctrl = get_service_data(dev);
462 
463 	cleanup_slots(ctrl);
464 	ctrl->hpc_ops->release_ctlr(ctrl);
465 }
466 
467 #ifdef CONFIG_PM
468 static int pciehp_suspend (struct pcie_device *dev, pm_message_t state)
469 {
470 	dev_info(&dev->device, "%s ENTRY\n", __func__);
471 	return 0;
472 }
473 
474 static int pciehp_resume (struct pcie_device *dev)
475 {
476 	dev_info(&dev->device, "%s ENTRY\n", __func__);
477 	if (pciehp_force) {
478 		struct controller *ctrl = get_service_data(dev);
479 		struct slot *t_slot;
480 		u8 status;
481 
482 		/* reinitialize the chipset's event detection logic */
483 		pcie_enable_notification(ctrl);
484 
485 		t_slot = pciehp_find_slot(ctrl, ctrl->slot_device_offset);
486 
487 		/* Check if slot is occupied */
488 		t_slot->hpc_ops->get_adapter_status(t_slot, &status);
489 		if (status)
490 			pciehp_enable_slot(t_slot);
491 		else
492 			pciehp_disable_slot(t_slot);
493 	}
494 	return 0;
495 }
496 #endif
497 
498 static struct pcie_port_service_id port_pci_ids[] = { {
499 	.vendor = PCI_ANY_ID,
500 	.device = PCI_ANY_ID,
501 	.port_type = PCIE_ANY_PORT,
502 	.service_type = PCIE_PORT_SERVICE_HP,
503 	.driver_data =	0,
504 	}, { /* end: all zeroes */ }
505 };
506 
507 static struct pcie_port_service_driver hpdriver_portdrv = {
508 	.name		= PCIE_MODULE_NAME,
509 	.id_table	= &port_pci_ids[0],
510 
511 	.probe		= pciehp_probe,
512 	.remove		= pciehp_remove,
513 
514 #ifdef	CONFIG_PM
515 	.suspend	= pciehp_suspend,
516 	.resume		= pciehp_resume,
517 #endif	/* PM */
518 };
519 
520 static int __init pcied_init(void)
521 {
522 	int retval = 0;
523 
524 	retval = pcie_port_service_register(&hpdriver_portdrv);
525  	dbg("pcie_port_service_register = %d\n", retval);
526   	info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
527  	if (retval)
528 		dbg("Failure to register service\n");
529 	return retval;
530 }
531 
532 static void __exit pcied_cleanup(void)
533 {
534 	dbg("unload_pciehpd()\n");
535 	pcie_port_service_unregister(&hpdriver_portdrv);
536 	info(DRIVER_DESC " version: " DRIVER_VERSION " unloaded\n");
537 }
538 
539 module_init(pcied_init);
540 module_exit(pcied_cleanup);
541