1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * ipmi_poweroff.c
4  *
5  * MontaVista IPMI Poweroff extension to sys_reboot
6  *
7  * Author: MontaVista Software, Inc.
8  *         Steven Dake <sdake@mvista.com>
9  *         Corey Minyard <cminyard@mvista.com>
10  *         source@mvista.com
11  *
12  * Copyright 2002,2004 MontaVista Software Inc.
13  */
14 #include <linux/module.h>
15 #include <linux/moduleparam.h>
16 #include <linux/proc_fs.h>
17 #include <linux/string.h>
18 #include <linux/completion.h>
19 #include <linux/pm.h>
20 #include <linux/kdev_t.h>
21 #include <linux/ipmi.h>
22 #include <linux/ipmi_smi.h>
23 
24 #define PFX "IPMI poweroff: "
25 
26 static void ipmi_po_smi_gone(int if_num);
27 static void ipmi_po_new_smi(int if_num, struct device *device);
28 
29 /* Definitions for controlling power off (if the system supports it).  It
30  * conveniently matches the IPMI chassis control values. */
31 #define IPMI_CHASSIS_POWER_DOWN		0	/* power down, the default. */
32 #define IPMI_CHASSIS_POWER_CYCLE	0x02	/* power cycle */
33 
34 /* the IPMI data command */
35 static int poweroff_powercycle;
36 
37 /* Which interface to use, -1 means the first we see. */
38 static int ifnum_to_use = -1;
39 
40 /* Our local state. */
41 static int ready;
42 static struct ipmi_user *ipmi_user;
43 static int ipmi_ifnum;
44 static void (*specific_poweroff_func)(struct ipmi_user *user);
45 
46 /* Holds the old poweroff function so we can restore it on removal. */
47 static void (*old_poweroff_func)(void);
48 
49 static int set_param_ifnum(const char *val, const struct kernel_param *kp)
50 {
51 	int rv = param_set_int(val, kp);
52 	if (rv)
53 		return rv;
54 	if ((ifnum_to_use < 0) || (ifnum_to_use == ipmi_ifnum))
55 		return 0;
56 
57 	ipmi_po_smi_gone(ipmi_ifnum);
58 	ipmi_po_new_smi(ifnum_to_use, NULL);
59 	return 0;
60 }
61 
62 module_param_call(ifnum_to_use, set_param_ifnum, param_get_int,
63 		  &ifnum_to_use, 0644);
64 MODULE_PARM_DESC(ifnum_to_use, "The interface number to use for the watchdog "
65 		 "timer.  Setting to -1 defaults to the first registered "
66 		 "interface");
67 
68 /* parameter definition to allow user to flag power cycle */
69 module_param(poweroff_powercycle, int, 0644);
70 MODULE_PARM_DESC(poweroff_powercycle,
71 		 " Set to non-zero to enable power cycle instead of power"
72 		 " down. Power cycle is contingent on hardware support,"
73 		 " otherwise it defaults back to power down.");
74 
75 /* Stuff from the get device id command. */
76 static unsigned int mfg_id;
77 static unsigned int prod_id;
78 static unsigned char capabilities;
79 static unsigned char ipmi_version;
80 
81 /*
82  * We use our own messages for this operation, we don't let the system
83  * allocate them, since we may be in a panic situation.  The whole
84  * thing is single-threaded, anyway, so multiple messages are not
85  * required.
86  */
87 static atomic_t dummy_count = ATOMIC_INIT(0);
88 static void dummy_smi_free(struct ipmi_smi_msg *msg)
89 {
90 	atomic_dec(&dummy_count);
91 }
92 static void dummy_recv_free(struct ipmi_recv_msg *msg)
93 {
94 	atomic_dec(&dummy_count);
95 }
96 static struct ipmi_smi_msg halt_smi_msg = {
97 	.done = dummy_smi_free
98 };
99 static struct ipmi_recv_msg halt_recv_msg = {
100 	.done = dummy_recv_free
101 };
102 
103 
104 /*
105  * Code to send a message and wait for the response.
106  */
107 
108 static void receive_handler(struct ipmi_recv_msg *recv_msg, void *handler_data)
109 {
110 	struct completion *comp = recv_msg->user_msg_data;
111 
112 	if (comp)
113 		complete(comp);
114 }
115 
116 static const struct ipmi_user_hndl ipmi_poweroff_handler = {
117 	.ipmi_recv_hndl = receive_handler
118 };
119 
120 
121 static int ipmi_request_wait_for_response(struct ipmi_user       *user,
122 					  struct ipmi_addr       *addr,
123 					  struct kernel_ipmi_msg *send_msg)
124 {
125 	int               rv;
126 	struct completion comp;
127 
128 	init_completion(&comp);
129 
130 	rv = ipmi_request_supply_msgs(user, addr, 0, send_msg, &comp,
131 				      &halt_smi_msg, &halt_recv_msg, 0);
132 	if (rv)
133 		return rv;
134 
135 	wait_for_completion(&comp);
136 
137 	return halt_recv_msg.msg.data[0];
138 }
139 
140 /* Wait for message to complete, spinning. */
141 static int ipmi_request_in_rc_mode(struct ipmi_user       *user,
142 				   struct ipmi_addr       *addr,
143 				   struct kernel_ipmi_msg *send_msg)
144 {
145 	int rv;
146 
147 	atomic_set(&dummy_count, 2);
148 	rv = ipmi_request_supply_msgs(user, addr, 0, send_msg, NULL,
149 				      &halt_smi_msg, &halt_recv_msg, 0);
150 	if (rv) {
151 		atomic_set(&dummy_count, 0);
152 		return rv;
153 	}
154 
155 	/*
156 	 * Spin until our message is done.
157 	 */
158 	while (atomic_read(&dummy_count) > 0) {
159 		ipmi_poll_interface(user);
160 		cpu_relax();
161 	}
162 
163 	return halt_recv_msg.msg.data[0];
164 }
165 
166 /*
167  * ATCA Support
168  */
169 
170 #define IPMI_NETFN_ATCA			0x2c
171 #define IPMI_ATCA_SET_POWER_CMD		0x11
172 #define IPMI_ATCA_GET_ADDR_INFO_CMD	0x01
173 #define IPMI_PICMG_ID			0
174 
175 #define IPMI_NETFN_OEM				0x2e
176 #define IPMI_ATCA_PPS_GRACEFUL_RESTART		0x11
177 #define IPMI_ATCA_PPS_IANA			"\x00\x40\x0A"
178 #define IPMI_MOTOROLA_MANUFACTURER_ID		0x0000A1
179 #define IPMI_MOTOROLA_PPS_IPMC_PRODUCT_ID	0x0051
180 
181 static void (*atca_oem_poweroff_hook)(struct ipmi_user *user);
182 
183 static void pps_poweroff_atca(struct ipmi_user *user)
184 {
185 	struct ipmi_system_interface_addr smi_addr;
186 	struct kernel_ipmi_msg            send_msg;
187 	int                               rv;
188 	/*
189 	 * Configure IPMI address for local access
190 	 */
191 	smi_addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
192 	smi_addr.channel = IPMI_BMC_CHANNEL;
193 	smi_addr.lun = 0;
194 
195 	printk(KERN_INFO PFX "PPS powerdown hook used");
196 
197 	send_msg.netfn = IPMI_NETFN_OEM;
198 	send_msg.cmd = IPMI_ATCA_PPS_GRACEFUL_RESTART;
199 	send_msg.data = IPMI_ATCA_PPS_IANA;
200 	send_msg.data_len = 3;
201 	rv = ipmi_request_in_rc_mode(user,
202 				     (struct ipmi_addr *) &smi_addr,
203 				     &send_msg);
204 	if (rv && rv != IPMI_UNKNOWN_ERR_COMPLETION_CODE) {
205 		printk(KERN_ERR PFX "Unable to send ATCA ,"
206 		       " IPMI error 0x%x\n", rv);
207 	}
208 	return;
209 }
210 
211 static int ipmi_atca_detect(struct ipmi_user *user)
212 {
213 	struct ipmi_system_interface_addr smi_addr;
214 	struct kernel_ipmi_msg            send_msg;
215 	int                               rv;
216 	unsigned char                     data[1];
217 
218 	/*
219 	 * Configure IPMI address for local access
220 	 */
221 	smi_addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
222 	smi_addr.channel = IPMI_BMC_CHANNEL;
223 	smi_addr.lun = 0;
224 
225 	/*
226 	 * Use get address info to check and see if we are ATCA
227 	 */
228 	send_msg.netfn = IPMI_NETFN_ATCA;
229 	send_msg.cmd = IPMI_ATCA_GET_ADDR_INFO_CMD;
230 	data[0] = IPMI_PICMG_ID;
231 	send_msg.data = data;
232 	send_msg.data_len = sizeof(data);
233 	rv = ipmi_request_wait_for_response(user,
234 					    (struct ipmi_addr *) &smi_addr,
235 					    &send_msg);
236 
237 	printk(KERN_INFO PFX "ATCA Detect mfg 0x%X prod 0x%X\n",
238 	       mfg_id, prod_id);
239 	if ((mfg_id == IPMI_MOTOROLA_MANUFACTURER_ID)
240 	    && (prod_id == IPMI_MOTOROLA_PPS_IPMC_PRODUCT_ID)) {
241 		printk(KERN_INFO PFX
242 		       "Installing Pigeon Point Systems Poweroff Hook\n");
243 		atca_oem_poweroff_hook = pps_poweroff_atca;
244 	}
245 	return !rv;
246 }
247 
248 static void ipmi_poweroff_atca(struct ipmi_user *user)
249 {
250 	struct ipmi_system_interface_addr smi_addr;
251 	struct kernel_ipmi_msg            send_msg;
252 	int                               rv;
253 	unsigned char                     data[4];
254 
255 	/*
256 	 * Configure IPMI address for local access
257 	 */
258 	smi_addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
259 	smi_addr.channel = IPMI_BMC_CHANNEL;
260 	smi_addr.lun = 0;
261 
262 	printk(KERN_INFO PFX "Powering down via ATCA power command\n");
263 
264 	/*
265 	 * Power down
266 	 */
267 	send_msg.netfn = IPMI_NETFN_ATCA;
268 	send_msg.cmd = IPMI_ATCA_SET_POWER_CMD;
269 	data[0] = IPMI_PICMG_ID;
270 	data[1] = 0; /* FRU id */
271 	data[2] = 0; /* Power Level */
272 	data[3] = 0; /* Don't change saved presets */
273 	send_msg.data = data;
274 	send_msg.data_len = sizeof(data);
275 	rv = ipmi_request_in_rc_mode(user,
276 				     (struct ipmi_addr *) &smi_addr,
277 				     &send_msg);
278 	/*
279 	 * At this point, the system may be shutting down, and most
280 	 * serial drivers (if used) will have interrupts turned off
281 	 * it may be better to ignore IPMI_UNKNOWN_ERR_COMPLETION_CODE
282 	 * return code
283 	 */
284 	if (rv && rv != IPMI_UNKNOWN_ERR_COMPLETION_CODE) {
285 		printk(KERN_ERR PFX "Unable to send ATCA powerdown message,"
286 		       " IPMI error 0x%x\n", rv);
287 		goto out;
288 	}
289 
290 	if (atca_oem_poweroff_hook)
291 		atca_oem_poweroff_hook(user);
292  out:
293 	return;
294 }
295 
296 /*
297  * CPI1 Support
298  */
299 
300 #define IPMI_NETFN_OEM_1				0xf8
301 #define OEM_GRP_CMD_SET_RESET_STATE		0x84
302 #define OEM_GRP_CMD_SET_POWER_STATE		0x82
303 #define IPMI_NETFN_OEM_8				0xf8
304 #define OEM_GRP_CMD_REQUEST_HOTSWAP_CTRL	0x80
305 #define OEM_GRP_CMD_GET_SLOT_GA			0xa3
306 #define IPMI_NETFN_SENSOR_EVT			0x10
307 #define IPMI_CMD_GET_EVENT_RECEIVER		0x01
308 
309 #define IPMI_CPI1_PRODUCT_ID		0x000157
310 #define IPMI_CPI1_MANUFACTURER_ID	0x0108
311 
312 static int ipmi_cpi1_detect(struct ipmi_user *user)
313 {
314 	return ((mfg_id == IPMI_CPI1_MANUFACTURER_ID)
315 		&& (prod_id == IPMI_CPI1_PRODUCT_ID));
316 }
317 
318 static void ipmi_poweroff_cpi1(struct ipmi_user *user)
319 {
320 	struct ipmi_system_interface_addr smi_addr;
321 	struct ipmi_ipmb_addr             ipmb_addr;
322 	struct kernel_ipmi_msg            send_msg;
323 	int                               rv;
324 	unsigned char                     data[1];
325 	int                               slot;
326 	unsigned char                     hotswap_ipmb;
327 	unsigned char                     aer_addr;
328 	unsigned char                     aer_lun;
329 
330 	/*
331 	 * Configure IPMI address for local access
332 	 */
333 	smi_addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
334 	smi_addr.channel = IPMI_BMC_CHANNEL;
335 	smi_addr.lun = 0;
336 
337 	printk(KERN_INFO PFX "Powering down via CPI1 power command\n");
338 
339 	/*
340 	 * Get IPMI ipmb address
341 	 */
342 	send_msg.netfn = IPMI_NETFN_OEM_8 >> 2;
343 	send_msg.cmd = OEM_GRP_CMD_GET_SLOT_GA;
344 	send_msg.data = NULL;
345 	send_msg.data_len = 0;
346 	rv = ipmi_request_in_rc_mode(user,
347 				     (struct ipmi_addr *) &smi_addr,
348 				     &send_msg);
349 	if (rv)
350 		goto out;
351 	slot = halt_recv_msg.msg.data[1];
352 	hotswap_ipmb = (slot > 9) ? (0xb0 + 2 * slot) : (0xae + 2 * slot);
353 
354 	/*
355 	 * Get active event receiver
356 	 */
357 	send_msg.netfn = IPMI_NETFN_SENSOR_EVT >> 2;
358 	send_msg.cmd = IPMI_CMD_GET_EVENT_RECEIVER;
359 	send_msg.data = NULL;
360 	send_msg.data_len = 0;
361 	rv = ipmi_request_in_rc_mode(user,
362 				     (struct ipmi_addr *) &smi_addr,
363 				     &send_msg);
364 	if (rv)
365 		goto out;
366 	aer_addr = halt_recv_msg.msg.data[1];
367 	aer_lun = halt_recv_msg.msg.data[2];
368 
369 	/*
370 	 * Setup IPMB address target instead of local target
371 	 */
372 	ipmb_addr.addr_type = IPMI_IPMB_ADDR_TYPE;
373 	ipmb_addr.channel = 0;
374 	ipmb_addr.slave_addr = aer_addr;
375 	ipmb_addr.lun = aer_lun;
376 
377 	/*
378 	 * Send request hotswap control to remove blade from dpv
379 	 */
380 	send_msg.netfn = IPMI_NETFN_OEM_8 >> 2;
381 	send_msg.cmd = OEM_GRP_CMD_REQUEST_HOTSWAP_CTRL;
382 	send_msg.data = &hotswap_ipmb;
383 	send_msg.data_len = 1;
384 	ipmi_request_in_rc_mode(user,
385 				(struct ipmi_addr *) &ipmb_addr,
386 				&send_msg);
387 
388 	/*
389 	 * Set reset asserted
390 	 */
391 	send_msg.netfn = IPMI_NETFN_OEM_1 >> 2;
392 	send_msg.cmd = OEM_GRP_CMD_SET_RESET_STATE;
393 	send_msg.data = data;
394 	data[0] = 1; /* Reset asserted state */
395 	send_msg.data_len = 1;
396 	rv = ipmi_request_in_rc_mode(user,
397 				     (struct ipmi_addr *) &smi_addr,
398 				     &send_msg);
399 	if (rv)
400 		goto out;
401 
402 	/*
403 	 * Power down
404 	 */
405 	send_msg.netfn = IPMI_NETFN_OEM_1 >> 2;
406 	send_msg.cmd = OEM_GRP_CMD_SET_POWER_STATE;
407 	send_msg.data = data;
408 	data[0] = 1; /* Power down state */
409 	send_msg.data_len = 1;
410 	rv = ipmi_request_in_rc_mode(user,
411 				     (struct ipmi_addr *) &smi_addr,
412 				     &send_msg);
413 	if (rv)
414 		goto out;
415 
416  out:
417 	return;
418 }
419 
420 /*
421  * ipmi_dell_chassis_detect()
422  * Dell systems with IPMI < 1.5 don't set the chassis capability bit
423  * but they can handle a chassis poweroff or powercycle command.
424  */
425 
426 #define DELL_IANA_MFR_ID {0xA2, 0x02, 0x00}
427 static int ipmi_dell_chassis_detect(struct ipmi_user *user)
428 {
429 	const char ipmi_version_major = ipmi_version & 0xF;
430 	const char ipmi_version_minor = (ipmi_version >> 4) & 0xF;
431 	const char mfr[3] = DELL_IANA_MFR_ID;
432 	if (!memcmp(mfr, &mfg_id, sizeof(mfr)) &&
433 	    ipmi_version_major <= 1 &&
434 	    ipmi_version_minor < 5)
435 		return 1;
436 	return 0;
437 }
438 
439 /*
440  * ipmi_hp_chassis_detect()
441  * HP PA-RISC servers rp3410/rp3440, the C8000 workstation and the rx2600 and
442  * zx6000 machines support IPMI vers 1 and don't set the chassis capability bit
443  * but they can handle a chassis poweroff or powercycle command.
444  */
445 
446 #define HP_IANA_MFR_ID 0x0b
447 #define HP_BMC_PROD_ID 0x8201
448 static int ipmi_hp_chassis_detect(struct ipmi_user *user)
449 {
450 	if (mfg_id == HP_IANA_MFR_ID
451 		&& prod_id == HP_BMC_PROD_ID
452 		&& ipmi_version == 1)
453 		return 1;
454 	return 0;
455 }
456 
457 /*
458  * Standard chassis support
459  */
460 
461 #define IPMI_NETFN_CHASSIS_REQUEST	0
462 #define IPMI_CHASSIS_CONTROL_CMD	0x02
463 
464 static int ipmi_chassis_detect(struct ipmi_user *user)
465 {
466 	/* Chassis support, use it. */
467 	return (capabilities & 0x80);
468 }
469 
470 static void ipmi_poweroff_chassis(struct ipmi_user *user)
471 {
472 	struct ipmi_system_interface_addr smi_addr;
473 	struct kernel_ipmi_msg            send_msg;
474 	int                               rv;
475 	unsigned char                     data[1];
476 
477 	/*
478 	 * Configure IPMI address for local access
479 	 */
480 	smi_addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
481 	smi_addr.channel = IPMI_BMC_CHANNEL;
482 	smi_addr.lun = 0;
483 
484  powercyclefailed:
485 	printk(KERN_INFO PFX "Powering %s via IPMI chassis control command\n",
486 		(poweroff_powercycle ? "cycle" : "down"));
487 
488 	/*
489 	 * Power down
490 	 */
491 	send_msg.netfn = IPMI_NETFN_CHASSIS_REQUEST;
492 	send_msg.cmd = IPMI_CHASSIS_CONTROL_CMD;
493 	if (poweroff_powercycle)
494 		data[0] = IPMI_CHASSIS_POWER_CYCLE;
495 	else
496 		data[0] = IPMI_CHASSIS_POWER_DOWN;
497 	send_msg.data = data;
498 	send_msg.data_len = sizeof(data);
499 	rv = ipmi_request_in_rc_mode(user,
500 				     (struct ipmi_addr *) &smi_addr,
501 				     &send_msg);
502 	if (rv) {
503 		if (poweroff_powercycle) {
504 			/* power cycle failed, default to power down */
505 			printk(KERN_ERR PFX "Unable to send chassis power " \
506 			       "cycle message, IPMI error 0x%x\n", rv);
507 			poweroff_powercycle = 0;
508 			goto powercyclefailed;
509 		}
510 
511 		printk(KERN_ERR PFX "Unable to send chassis power " \
512 		       "down message, IPMI error 0x%x\n", rv);
513 	}
514 }
515 
516 
517 /* Table of possible power off functions. */
518 struct poweroff_function {
519 	char *platform_type;
520 	int  (*detect)(struct ipmi_user *user);
521 	void (*poweroff_func)(struct ipmi_user *user);
522 };
523 
524 static struct poweroff_function poweroff_functions[] = {
525 	{ .platform_type	= "ATCA",
526 	  .detect		= ipmi_atca_detect,
527 	  .poweroff_func	= ipmi_poweroff_atca },
528 	{ .platform_type	= "CPI1",
529 	  .detect		= ipmi_cpi1_detect,
530 	  .poweroff_func	= ipmi_poweroff_cpi1 },
531 	{ .platform_type	= "chassis",
532 	  .detect		= ipmi_dell_chassis_detect,
533 	  .poweroff_func	= ipmi_poweroff_chassis },
534 	{ .platform_type	= "chassis",
535 	  .detect		= ipmi_hp_chassis_detect,
536 	  .poweroff_func	= ipmi_poweroff_chassis },
537 	/* Chassis should generally be last, other things should override
538 	   it. */
539 	{ .platform_type	= "chassis",
540 	  .detect		= ipmi_chassis_detect,
541 	  .poweroff_func	= ipmi_poweroff_chassis },
542 };
543 #define NUM_PO_FUNCS ARRAY_SIZE(poweroff_functions)
544 
545 
546 /* Called on a powerdown request. */
547 static void ipmi_poweroff_function(void)
548 {
549 	if (!ready)
550 		return;
551 
552 	/* Use run-to-completion mode, since interrupts may be off. */
553 	specific_poweroff_func(ipmi_user);
554 }
555 
556 /* Wait for an IPMI interface to be installed, the first one installed
557    will be grabbed by this code and used to perform the powerdown. */
558 static void ipmi_po_new_smi(int if_num, struct device *device)
559 {
560 	struct ipmi_system_interface_addr smi_addr;
561 	struct kernel_ipmi_msg            send_msg;
562 	int                               rv;
563 	int                               i;
564 
565 	if (ready)
566 		return;
567 
568 	if ((ifnum_to_use >= 0) && (ifnum_to_use != if_num))
569 		return;
570 
571 	rv = ipmi_create_user(if_num, &ipmi_poweroff_handler, NULL,
572 			      &ipmi_user);
573 	if (rv) {
574 		printk(KERN_ERR PFX "could not create IPMI user, error %d\n",
575 		       rv);
576 		return;
577 	}
578 
579 	ipmi_ifnum = if_num;
580 
581 	/*
582 	 * Do a get device ide and store some results, since this is
583 	 * used by several functions.
584 	 */
585 	smi_addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
586 	smi_addr.channel = IPMI_BMC_CHANNEL;
587 	smi_addr.lun = 0;
588 
589 	send_msg.netfn = IPMI_NETFN_APP_REQUEST;
590 	send_msg.cmd = IPMI_GET_DEVICE_ID_CMD;
591 	send_msg.data = NULL;
592 	send_msg.data_len = 0;
593 	rv = ipmi_request_wait_for_response(ipmi_user,
594 					    (struct ipmi_addr *) &smi_addr,
595 					    &send_msg);
596 	if (rv) {
597 		printk(KERN_ERR PFX "Unable to send IPMI get device id info,"
598 		       " IPMI error 0x%x\n", rv);
599 		goto out_err;
600 	}
601 
602 	if (halt_recv_msg.msg.data_len < 12) {
603 		printk(KERN_ERR PFX "(chassis) IPMI get device id info too,"
604 		       " short, was %d bytes, needed %d bytes\n",
605 		       halt_recv_msg.msg.data_len, 12);
606 		goto out_err;
607 	}
608 
609 	mfg_id = (halt_recv_msg.msg.data[7]
610 		  | (halt_recv_msg.msg.data[8] << 8)
611 		  | (halt_recv_msg.msg.data[9] << 16));
612 	prod_id = (halt_recv_msg.msg.data[10]
613 		   | (halt_recv_msg.msg.data[11] << 8));
614 	capabilities = halt_recv_msg.msg.data[6];
615 	ipmi_version = halt_recv_msg.msg.data[5];
616 
617 
618 	/* Scan for a poweroff method */
619 	for (i = 0; i < NUM_PO_FUNCS; i++) {
620 		if (poweroff_functions[i].detect(ipmi_user))
621 			goto found;
622 	}
623 
624  out_err:
625 	printk(KERN_ERR PFX "Unable to find a poweroff function that"
626 	       " will work, giving up\n");
627 	ipmi_destroy_user(ipmi_user);
628 	return;
629 
630  found:
631 	printk(KERN_INFO PFX "Found a %s style poweroff function\n",
632 	       poweroff_functions[i].platform_type);
633 	specific_poweroff_func = poweroff_functions[i].poweroff_func;
634 	old_poweroff_func = pm_power_off;
635 	pm_power_off = ipmi_poweroff_function;
636 	ready = 1;
637 }
638 
639 static void ipmi_po_smi_gone(int if_num)
640 {
641 	if (!ready)
642 		return;
643 
644 	if (ipmi_ifnum != if_num)
645 		return;
646 
647 	ready = 0;
648 	ipmi_destroy_user(ipmi_user);
649 	pm_power_off = old_poweroff_func;
650 }
651 
652 static struct ipmi_smi_watcher smi_watcher = {
653 	.owner    = THIS_MODULE,
654 	.new_smi  = ipmi_po_new_smi,
655 	.smi_gone = ipmi_po_smi_gone
656 };
657 
658 
659 #ifdef CONFIG_PROC_FS
660 #include <linux/sysctl.h>
661 
662 static struct ctl_table ipmi_table[] = {
663 	{ .procname	= "poweroff_powercycle",
664 	  .data		= &poweroff_powercycle,
665 	  .maxlen	= sizeof(poweroff_powercycle),
666 	  .mode		= 0644,
667 	  .proc_handler	= proc_dointvec },
668 	{ }
669 };
670 
671 static struct ctl_table ipmi_dir_table[] = {
672 	{ .procname	= "ipmi",
673 	  .mode		= 0555,
674 	  .child	= ipmi_table },
675 	{ }
676 };
677 
678 static struct ctl_table ipmi_root_table[] = {
679 	{ .procname	= "dev",
680 	  .mode		= 0555,
681 	  .child	= ipmi_dir_table },
682 	{ }
683 };
684 
685 static struct ctl_table_header *ipmi_table_header;
686 #endif /* CONFIG_PROC_FS */
687 
688 /*
689  * Startup and shutdown functions.
690  */
691 static int __init ipmi_poweroff_init(void)
692 {
693 	int rv;
694 
695 	printk(KERN_INFO "Copyright (C) 2004 MontaVista Software -"
696 	       " IPMI Powerdown via sys_reboot.\n");
697 
698 	if (poweroff_powercycle)
699 		printk(KERN_INFO PFX "Power cycle is enabled.\n");
700 
701 #ifdef CONFIG_PROC_FS
702 	ipmi_table_header = register_sysctl_table(ipmi_root_table);
703 	if (!ipmi_table_header) {
704 		printk(KERN_ERR PFX "Unable to register powercycle sysctl\n");
705 		rv = -ENOMEM;
706 		goto out_err;
707 	}
708 #endif
709 
710 	rv = ipmi_smi_watcher_register(&smi_watcher);
711 
712 #ifdef CONFIG_PROC_FS
713 	if (rv) {
714 		unregister_sysctl_table(ipmi_table_header);
715 		printk(KERN_ERR PFX "Unable to register SMI watcher: %d\n", rv);
716 		goto out_err;
717 	}
718 
719  out_err:
720 #endif
721 	return rv;
722 }
723 
724 #ifdef MODULE
725 static void __exit ipmi_poweroff_cleanup(void)
726 {
727 	int rv;
728 
729 #ifdef CONFIG_PROC_FS
730 	unregister_sysctl_table(ipmi_table_header);
731 #endif
732 
733 	ipmi_smi_watcher_unregister(&smi_watcher);
734 
735 	if (ready) {
736 		rv = ipmi_destroy_user(ipmi_user);
737 		if (rv)
738 			printk(KERN_ERR PFX "could not cleanup the IPMI"
739 			       " user: 0x%x\n", rv);
740 		pm_power_off = old_poweroff_func;
741 	}
742 }
743 module_exit(ipmi_poweroff_cleanup);
744 #endif
745 
746 module_init(ipmi_poweroff_init);
747 MODULE_LICENSE("GPL");
748 MODULE_AUTHOR("Corey Minyard <minyard@mvista.com>");
749 MODULE_DESCRIPTION("IPMI Poweroff extension to sys_reboot");
750