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