xref: /openbmc/linux/drivers/pci/hotplug/pciehp_core.c (revision df2634f43f5106947f3735a0b61a6527a4b278cd)
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/slab.h>
34 #include <linux/types.h>
35 #include <linux/pci.h>
36 #include "pciehp.h"
37 #include <linux/interrupt.h>
38 #include <linux/time.h>
39 
40 /* Global variables */
41 int pciehp_debug;
42 int pciehp_poll_mode;
43 int pciehp_poll_time;
44 int pciehp_force;
45 struct workqueue_struct *pciehp_wq;
46 struct workqueue_struct *pciehp_ordered_wq;
47 
48 #define DRIVER_VERSION	"0.4"
49 #define DRIVER_AUTHOR	"Dan Zink <dan.zink@compaq.com>, Greg Kroah-Hartman <greg@kroah.com>, Dely Sy <dely.l.sy@intel.com>"
50 #define DRIVER_DESC	"PCI Express Hot Plug Controller Driver"
51 
52 MODULE_AUTHOR(DRIVER_AUTHOR);
53 MODULE_DESCRIPTION(DRIVER_DESC);
54 MODULE_LICENSE("GPL");
55 
56 module_param(pciehp_debug, bool, 0644);
57 module_param(pciehp_poll_mode, bool, 0644);
58 module_param(pciehp_poll_time, int, 0644);
59 module_param(pciehp_force, 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 OSHP is missing");
64 
65 #define PCIE_MODULE_NAME "pciehp"
66 
67 static int set_attention_status (struct hotplug_slot *slot, u8 value);
68 static int enable_slot		(struct hotplug_slot *slot);
69 static int disable_slot		(struct hotplug_slot *slot);
70 static int get_power_status	(struct hotplug_slot *slot, u8 *value);
71 static int get_attention_status	(struct hotplug_slot *slot, u8 *value);
72 static int get_latch_status	(struct hotplug_slot *slot, u8 *value);
73 static int get_adapter_status	(struct hotplug_slot *slot, u8 *value);
74 
75 /**
76  * release_slot - free up the memory used by a slot
77  * @hotplug_slot: slot to free
78  */
79 static void release_slot(struct hotplug_slot *hotplug_slot)
80 {
81 	struct slot *slot = hotplug_slot->private;
82 
83 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
84 		 __func__, hotplug_slot_name(hotplug_slot));
85 
86 	kfree(hotplug_slot->ops);
87 	kfree(hotplug_slot->info);
88 	kfree(hotplug_slot);
89 }
90 
91 static int init_slot(struct controller *ctrl)
92 {
93 	struct slot *slot = ctrl->slot;
94 	struct hotplug_slot *hotplug = NULL;
95 	struct hotplug_slot_info *info = NULL;
96 	struct hotplug_slot_ops *ops = NULL;
97 	char name[SLOT_NAME_SIZE];
98 	int retval = -ENOMEM;
99 
100 	hotplug = kzalloc(sizeof(*hotplug), GFP_KERNEL);
101 	if (!hotplug)
102 		goto out;
103 
104 	info = kzalloc(sizeof(*info), GFP_KERNEL);
105 	if (!info)
106 		goto out;
107 
108 	/* Setup hotplug slot ops */
109 	ops = kzalloc(sizeof(*ops), GFP_KERNEL);
110 	if (!ops)
111 		goto out;
112 	ops->enable_slot = enable_slot;
113 	ops->disable_slot = disable_slot;
114 	ops->get_power_status = get_power_status;
115 	ops->get_adapter_status = get_adapter_status;
116 	if (MRL_SENS(ctrl))
117 		ops->get_latch_status = get_latch_status;
118 	if (ATTN_LED(ctrl)) {
119 		ops->get_attention_status = get_attention_status;
120 		ops->set_attention_status = set_attention_status;
121 	}
122 
123 	/* register this slot with the hotplug pci core */
124 	hotplug->info = info;
125 	hotplug->private = slot;
126 	hotplug->release = &release_slot;
127 	hotplug->ops = ops;
128 	slot->hotplug_slot = hotplug;
129 	snprintf(name, SLOT_NAME_SIZE, "%u", PSN(ctrl));
130 
131 	ctrl_dbg(ctrl, "Registering domain:bus:dev=%04x:%02x:00 sun=%x\n",
132 		 pci_domain_nr(ctrl->pcie->port->subordinate),
133 		 ctrl->pcie->port->subordinate->number, PSN(ctrl));
134 	retval = pci_hp_register(hotplug,
135 				 ctrl->pcie->port->subordinate, 0, name);
136 	if (retval)
137 		ctrl_err(ctrl,
138 			 "pci_hp_register failed with error %d\n", retval);
139 out:
140 	if (retval) {
141 		kfree(ops);
142 		kfree(info);
143 		kfree(hotplug);
144 	}
145 	return retval;
146 }
147 
148 static void cleanup_slot(struct controller *ctrl)
149 {
150 	pci_hp_deregister(ctrl->slot->hotplug_slot);
151 }
152 
153 /*
154  * set_attention_status - Turns the Amber LED for a slot on, off or blink
155  */
156 static int set_attention_status(struct hotplug_slot *hotplug_slot, u8 status)
157 {
158 	struct slot *slot = hotplug_slot->private;
159 
160 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
161 		  __func__, slot_name(slot));
162 
163 	return pciehp_set_attention_status(slot, status);
164 }
165 
166 
167 static int enable_slot(struct hotplug_slot *hotplug_slot)
168 {
169 	struct slot *slot = hotplug_slot->private;
170 
171 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
172 		 __func__, slot_name(slot));
173 
174 	return pciehp_sysfs_enable_slot(slot);
175 }
176 
177 
178 static int disable_slot(struct hotplug_slot *hotplug_slot)
179 {
180 	struct slot *slot = hotplug_slot->private;
181 
182 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
183 		  __func__, slot_name(slot));
184 
185 	return pciehp_sysfs_disable_slot(slot);
186 }
187 
188 static int get_power_status(struct hotplug_slot *hotplug_slot, u8 *value)
189 {
190 	struct slot *slot = hotplug_slot->private;
191 
192 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
193 		  __func__, slot_name(slot));
194 
195 	return pciehp_get_power_status(slot, value);
196 }
197 
198 static int get_attention_status(struct hotplug_slot *hotplug_slot, u8 *value)
199 {
200 	struct slot *slot = hotplug_slot->private;
201 
202 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
203 		  __func__, slot_name(slot));
204 
205 	return pciehp_get_attention_status(slot, value);
206 }
207 
208 static int get_latch_status(struct hotplug_slot *hotplug_slot, u8 *value)
209 {
210 	struct slot *slot = hotplug_slot->private;
211 
212 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
213 		 __func__, slot_name(slot));
214 
215 	return pciehp_get_latch_status(slot, value);
216 }
217 
218 static int get_adapter_status(struct hotplug_slot *hotplug_slot, u8 *value)
219 {
220 	struct slot *slot = hotplug_slot->private;
221 
222 	ctrl_dbg(slot->ctrl, "%s: physical_slot = %s\n",
223 		 __func__, slot_name(slot));
224 
225 	return pciehp_get_adapter_status(slot, value);
226 }
227 
228 static int pciehp_probe(struct pcie_device *dev)
229 {
230 	int rc;
231 	struct controller *ctrl;
232 	struct slot *slot;
233 	u8 occupied, poweron;
234 
235 	if (pciehp_force)
236 		dev_info(&dev->device,
237 			 "Bypassing BIOS check for pciehp use on %s\n",
238 			 pci_name(dev->port));
239 	else if (pciehp_acpi_slot_detection_check(dev->port))
240 		goto err_out_none;
241 
242 	ctrl = pcie_init(dev);
243 	if (!ctrl) {
244 		dev_err(&dev->device, "Controller initialization failed\n");
245 		goto err_out_none;
246 	}
247 	set_service_data(dev, ctrl);
248 
249 	/* Setup the slot information structures */
250 	rc = init_slot(ctrl);
251 	if (rc) {
252 		if (rc == -EBUSY)
253 			ctrl_warn(ctrl, "Slot already registered by another "
254 				  "hotplug driver\n");
255 		else
256 			ctrl_err(ctrl, "Slot initialization failed\n");
257 		goto err_out_release_ctlr;
258 	}
259 
260 	/* Enable events after we have setup the data structures */
261 	rc = pcie_init_notification(ctrl);
262 	if (rc) {
263 		ctrl_err(ctrl, "Notification initialization failed\n");
264 		goto err_out_free_ctrl_slot;
265 	}
266 
267 	/* Check if slot is occupied */
268 	slot = ctrl->slot;
269 	pciehp_get_adapter_status(slot, &occupied);
270 	pciehp_get_power_status(slot, &poweron);
271 	if (occupied && pciehp_force)
272 		pciehp_enable_slot(slot);
273 	/* If empty slot's power status is on, turn power off */
274 	if (!occupied && poweron && POWER_CTRL(ctrl))
275 		pciehp_power_off_slot(slot);
276 
277 	return 0;
278 
279 err_out_free_ctrl_slot:
280 	cleanup_slot(ctrl);
281 err_out_release_ctlr:
282 	pciehp_release_ctrl(ctrl);
283 err_out_none:
284 	return -ENODEV;
285 }
286 
287 static void pciehp_remove(struct pcie_device *dev)
288 {
289 	struct controller *ctrl = get_service_data(dev);
290 
291 	cleanup_slot(ctrl);
292 	pciehp_release_ctrl(ctrl);
293 }
294 
295 #ifdef CONFIG_PM
296 static int pciehp_suspend (struct pcie_device *dev)
297 {
298 	dev_info(&dev->device, "%s ENTRY\n", __func__);
299 	return 0;
300 }
301 
302 static int pciehp_resume (struct pcie_device *dev)
303 {
304 	dev_info(&dev->device, "%s ENTRY\n", __func__);
305 	if (pciehp_force) {
306 		struct controller *ctrl = get_service_data(dev);
307 		struct slot *slot;
308 		u8 status;
309 
310 		/* reinitialize the chipset's event detection logic */
311 		pcie_enable_notification(ctrl);
312 
313 		slot = ctrl->slot;
314 
315 		/* Check if slot is occupied */
316 		pciehp_get_adapter_status(slot, &status);
317 		if (status)
318 			pciehp_enable_slot(slot);
319 		else
320 			pciehp_disable_slot(slot);
321 	}
322 	return 0;
323 }
324 #endif /* PM */
325 
326 static struct pcie_port_service_driver hpdriver_portdrv = {
327 	.name		= PCIE_MODULE_NAME,
328 	.port_type	= PCIE_ANY_PORT,
329 	.service	= PCIE_PORT_SERVICE_HP,
330 
331 	.probe		= pciehp_probe,
332 	.remove		= pciehp_remove,
333 
334 #ifdef	CONFIG_PM
335 	.suspend	= pciehp_suspend,
336 	.resume		= pciehp_resume,
337 #endif	/* PM */
338 };
339 
340 static int __init pcied_init(void)
341 {
342 	int retval = 0;
343 
344 	pciehp_wq = alloc_workqueue("pciehp", 0, 0);
345 	if (!pciehp_wq)
346 		return -ENOMEM;
347 
348 	pciehp_ordered_wq = alloc_ordered_workqueue("pciehp_ordered", 0);
349 	if (!pciehp_ordered_wq) {
350 		destroy_workqueue(pciehp_wq);
351 		return -ENOMEM;
352 	}
353 
354 	pciehp_firmware_init();
355 	retval = pcie_port_service_register(&hpdriver_portdrv);
356  	dbg("pcie_port_service_register = %d\n", retval);
357   	info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
358  	if (retval) {
359 		destroy_workqueue(pciehp_ordered_wq);
360 		destroy_workqueue(pciehp_wq);
361 		dbg("Failure to register service\n");
362 	}
363 	return retval;
364 }
365 
366 static void __exit pcied_cleanup(void)
367 {
368 	dbg("unload_pciehpd()\n");
369 	destroy_workqueue(pciehp_ordered_wq);
370 	destroy_workqueue(pciehp_wq);
371 	pcie_port_service_unregister(&hpdriver_portdrv);
372 	info(DRIVER_DESC " version: " DRIVER_VERSION " unloaded\n");
373 }
374 
375 module_init(pcied_init);
376 module_exit(pcied_cleanup);
377