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v3.1
 
  1/*
  2 *  acpi_ipmi.c - ACPI IPMI opregion
  3 *
  4 *  Copyright (C) 2010 Intel Corporation
  5 *  Copyright (C) 2010 Zhao Yakui <yakui.zhao@intel.com>
  6 *
  7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  8 *
  9 *  This program is free software; you can redistribute it and/or modify
 10 *  it under the terms of the GNU General Public License as published by
 11 *  the Free Software Foundation; either version 2 of the License, or (at
 12 *  your option) any later version.
 13 *
 14 *  This program is distributed in the hope that it will be useful, but
 15 *  WITHOUT ANY WARRANTY; without even the implied warranty of
 16 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 17 *  General Public License for more details.
 18 *
 19 *  You should have received a copy of the GNU General Public License along
 20 *  with this program; if not, write to the Free Software Foundation, Inc.,
 21 *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
 22 *
 23 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 24 */
 25
 26#include <linux/kernel.h>
 27#include <linux/module.h>
 28#include <linux/init.h>
 29#include <linux/types.h>
 30#include <linux/delay.h>
 31#include <linux/proc_fs.h>
 32#include <linux/seq_file.h>
 33#include <linux/interrupt.h>
 34#include <linux/list.h>
 35#include <linux/spinlock.h>
 36#include <linux/io.h>
 37#include <acpi/acpi_bus.h>
 38#include <acpi/acpi_drivers.h>
 39#include <linux/ipmi.h>
 40#include <linux/device.h>
 41#include <linux/pnp.h>
 42
 43MODULE_AUTHOR("Zhao Yakui");
 44MODULE_DESCRIPTION("ACPI IPMI Opregion driver");
 45MODULE_LICENSE("GPL");
 46
 47#define IPMI_FLAGS_HANDLER_INSTALL	0
 48
 49#define ACPI_IPMI_OK			0
 50#define ACPI_IPMI_TIMEOUT		0x10
 51#define ACPI_IPMI_UNKNOWN		0x07
 52/* the IPMI timeout is 5s */
 53#define IPMI_TIMEOUT			(5 * HZ)
 
 
 
 54
 55struct acpi_ipmi_device {
 56	/* the device list attached to driver_data.ipmi_devices */
 57	struct list_head head;
 
 58	/* the IPMI request message list */
 59	struct list_head tx_msg_list;
 60	struct mutex	tx_msg_lock;
 
 61	acpi_handle handle;
 62	struct pnp_dev *pnp_dev;
 63	ipmi_user_t	user_interface;
 64	int ipmi_ifnum; /* IPMI interface number */
 65	long curr_msgid;
 66	unsigned long flags;
 67	struct ipmi_smi_info smi_data;
 68};
 69
 70struct ipmi_driver_data {
 71	struct list_head	ipmi_devices;
 72	struct ipmi_smi_watcher	bmc_events;
 73	struct ipmi_user_hndl	ipmi_hndlrs;
 74	struct mutex		ipmi_lock;
 
 
 
 
 
 
 
 
 
 
 75};
 76
 77struct acpi_ipmi_msg {
 78	struct list_head head;
 
 79	/*
 80	 * General speaking the addr type should be SI_ADDR_TYPE. And
 81	 * the addr channel should be BMC.
 82	 * In fact it can also be IPMB type. But we will have to
 83	 * parse it from the Netfn command buffer. It is so complex
 84	 * that it is skipped.
 85	 */
 86	struct ipmi_addr addr;
 87	long tx_msgid;
 
 88	/* it is used to track whether the IPMI message is finished */
 89	struct completion tx_complete;
 
 90	struct kernel_ipmi_msg tx_message;
 91	int	msg_done;
 92	/* tx data . And copy it from ACPI object buffer */
 93	u8	tx_data[64];
 94	int	tx_len;
 95	u8	rx_data[64];
 96	int	rx_len;
 97	struct acpi_ipmi_device *device;
 
 98};
 99
100/* IPMI request/response buffer per ACPI 4.0, sec 5.5.2.4.3.2 */
101struct acpi_ipmi_buffer {
102	u8 status;
103	u8 length;
104	u8 data[64];
105};
106
107static void ipmi_register_bmc(int iface, struct device *dev);
108static void ipmi_bmc_gone(int iface);
109static void ipmi_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data);
110static void acpi_add_ipmi_device(struct acpi_ipmi_device *ipmi_device);
111static void acpi_remove_ipmi_device(struct acpi_ipmi_device *ipmi_device);
112
113static struct ipmi_driver_data driver_data = {
114	.ipmi_devices = LIST_HEAD_INIT(driver_data.ipmi_devices),
115	.bmc_events = {
116		.owner = THIS_MODULE,
117		.new_smi = ipmi_register_bmc,
118		.smi_gone = ipmi_bmc_gone,
119	},
120	.ipmi_hndlrs = {
121		.ipmi_recv_hndl = ipmi_msg_handler,
122	},
 
123};
124
125static struct acpi_ipmi_msg *acpi_alloc_ipmi_msg(struct acpi_ipmi_device *ipmi)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
126{
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
127	struct acpi_ipmi_msg *ipmi_msg;
128	struct pnp_dev *pnp_dev = ipmi->pnp_dev;
 
 
 
129
130	ipmi_msg = kzalloc(sizeof(struct acpi_ipmi_msg), GFP_KERNEL);
131	if (!ipmi_msg)	{
132		dev_warn(&pnp_dev->dev, "Can't allocate memory for ipmi_msg\n");
133		return NULL;
134	}
 
 
135	init_completion(&ipmi_msg->tx_complete);
136	INIT_LIST_HEAD(&ipmi_msg->head);
137	ipmi_msg->device = ipmi;
 
 
138	return ipmi_msg;
139}
140
141#define		IPMI_OP_RGN_NETFN(offset)	((offset >> 8) & 0xff)
142#define		IPMI_OP_RGN_CMD(offset)		(offset & 0xff)
143static void acpi_format_ipmi_msg(struct acpi_ipmi_msg *tx_msg,
144				acpi_physical_address address,
145				acpi_integer *value)
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
146{
147	struct kernel_ipmi_msg *msg;
148	struct acpi_ipmi_buffer *buffer;
149	struct acpi_ipmi_device *device;
 
150
151	msg = &tx_msg->tx_message;
 
152	/*
153	 * IPMI network function and command are encoded in the address
154	 * within the IPMI OpRegion; see ACPI 4.0, sec 5.5.2.4.3.
155	 */
156	msg->netfn = IPMI_OP_RGN_NETFN(address);
157	msg->cmd = IPMI_OP_RGN_CMD(address);
158	msg->data = tx_msg->tx_data;
 
159	/*
160	 * value is the parameter passed by the IPMI opregion space handler.
161	 * It points to the IPMI request message buffer
162	 */
163	buffer = (struct acpi_ipmi_buffer *)value;
 
164	/* copy the tx message data */
 
 
 
 
 
 
165	msg->data_len = buffer->length;
166	memcpy(tx_msg->tx_data, buffer->data, msg->data_len);
 
167	/*
168	 * now the default type is SYSTEM_INTERFACE and channel type is BMC.
169	 * If the netfn is APP_REQUEST and the cmd is SEND_MESSAGE,
170	 * the addr type should be changed to IPMB. Then we will have to parse
171	 * the IPMI request message buffer to get the IPMB address.
172	 * If so, please fix me.
173	 */
174	tx_msg->addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
175	tx_msg->addr.channel = IPMI_BMC_CHANNEL;
176	tx_msg->addr.data[0] = 0;
177
178	/* Get the msgid */
179	device = tx_msg->device;
180	mutex_lock(&device->tx_msg_lock);
 
181	device->curr_msgid++;
182	tx_msg->tx_msgid = device->curr_msgid;
183	mutex_unlock(&device->tx_msg_lock);
 
 
184}
185
186static void acpi_format_ipmi_response(struct acpi_ipmi_msg *msg,
187		acpi_integer *value, int rem_time)
188{
189	struct acpi_ipmi_buffer *buffer;
190
191	/*
192	 * value is also used as output parameter. It represents the response
193	 * IPMI message returned by IPMI command.
194	 */
195	buffer = (struct acpi_ipmi_buffer *)value;
196	if (!rem_time && !msg->msg_done) {
197		buffer->status = ACPI_IPMI_TIMEOUT;
198		return;
199	}
200	/*
201	 * If the flag of msg_done is not set or the recv length is zero, it
202	 * means that the IPMI command is not executed correctly.
203	 * The status code will be ACPI_IPMI_UNKNOWN.
204	 */
205	if (!msg->msg_done || !msg->rx_len) {
206		buffer->status = ACPI_IPMI_UNKNOWN;
207		return;
208	}
209	/*
210	 * If the IPMI response message is obtained correctly, the status code
211	 * will be ACPI_IPMI_OK
212	 */
213	buffer->status = ACPI_IPMI_OK;
214	buffer->length = msg->rx_len;
215	memcpy(buffer->data, msg->rx_data, msg->rx_len);
216}
217
218static void ipmi_flush_tx_msg(struct acpi_ipmi_device *ipmi)
219{
220	struct acpi_ipmi_msg *tx_msg, *temp;
221	int count = HZ / 10;
222	struct pnp_dev *pnp_dev = ipmi->pnp_dev;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
223
224	list_for_each_entry_safe(tx_msg, temp, &ipmi->tx_msg_list, head) {
225		/* wake up the sleep thread on the Tx msg */
226		complete(&tx_msg->tx_complete);
 
 
227	}
 
 
228
229	/* wait for about 100ms to flush the tx message list */
230	while (count--) {
231		if (list_empty(&ipmi->tx_msg_list))
 
 
 
 
 
 
 
 
232			break;
233		schedule_timeout(1);
234	}
235	if (!list_empty(&ipmi->tx_msg_list))
236		dev_warn(&pnp_dev->dev, "tx msg list is not NULL\n");
 
 
237}
238
239static void ipmi_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data)
240{
241	struct acpi_ipmi_device *ipmi_device = user_msg_data;
242	int msg_found = 0;
243	struct acpi_ipmi_msg *tx_msg;
244	struct pnp_dev *pnp_dev = ipmi_device->pnp_dev;
245
246	if (msg->user != ipmi_device->user_interface) {
247		dev_warn(&pnp_dev->dev, "Unexpected response is returned. "
248			"returned user %p, expected user %p\n",
249			msg->user, ipmi_device->user_interface);
250		ipmi_free_recv_msg(msg);
251		return;
252	}
253	mutex_lock(&ipmi_device->tx_msg_lock);
254	list_for_each_entry(tx_msg, &ipmi_device->tx_msg_list, head) {
255		if (msg->msgid == tx_msg->tx_msgid) {
256			msg_found = 1;
 
 
257			break;
258		}
259	}
 
260
261	mutex_unlock(&ipmi_device->tx_msg_lock);
262	if (!msg_found) {
263		dev_warn(&pnp_dev->dev, "Unexpected response (msg id %ld) is "
264			"returned.\n", msg->msgid);
265		ipmi_free_recv_msg(msg);
266		return;
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
267	}
268
269	if (msg->msg.data_len) {
270		/* copy the response data to Rx_data buffer */
271		memcpy(tx_msg->rx_data, msg->msg_data, msg->msg.data_len);
272		tx_msg->rx_len = msg->msg.data_len;
273		tx_msg->msg_done = 1;
274	}
275	complete(&tx_msg->tx_complete);
 
 
276	ipmi_free_recv_msg(msg);
277};
278
279static void ipmi_register_bmc(int iface, struct device *dev)
280{
281	struct acpi_ipmi_device *ipmi_device, *temp;
282	struct pnp_dev *pnp_dev;
283	ipmi_user_t		user;
284	int err;
285	struct ipmi_smi_info smi_data;
286	acpi_handle handle;
287
288	err = ipmi_get_smi_info(iface, &smi_data);
289
290	if (err)
291		return;
292
293	if (smi_data.addr_src != SI_ACPI) {
294		put_device(smi_data.dev);
295		return;
296	}
297
298	handle = smi_data.addr_info.acpi_info.acpi_handle;
 
 
 
 
 
 
 
 
299
300	mutex_lock(&driver_data.ipmi_lock);
301	list_for_each_entry(temp, &driver_data.ipmi_devices, head) {
302		/*
303		 * if the corresponding ACPI handle is already added
304		 * to the device list, don't add it again.
305		 */
306		if (temp->handle == handle)
307			goto out;
308	}
309
310	ipmi_device = kzalloc(sizeof(*ipmi_device), GFP_KERNEL);
311
312	if (!ipmi_device)
313		goto out;
314
315	pnp_dev = to_pnp_dev(smi_data.dev);
316	ipmi_device->handle = handle;
317	ipmi_device->pnp_dev = pnp_dev;
318
319	err = ipmi_create_user(iface, &driver_data.ipmi_hndlrs,
320					ipmi_device, &user);
321	if (err) {
322		dev_warn(&pnp_dev->dev, "Can't create IPMI user interface\n");
323		kfree(ipmi_device);
324		goto out;
325	}
326	acpi_add_ipmi_device(ipmi_device);
327	ipmi_device->user_interface = user;
328	ipmi_device->ipmi_ifnum = iface;
329	mutex_unlock(&driver_data.ipmi_lock);
330	memcpy(&ipmi_device->smi_data, &smi_data, sizeof(struct ipmi_smi_info));
 
331	return;
332
333out:
334	mutex_unlock(&driver_data.ipmi_lock);
 
 
335	put_device(smi_data.dev);
336	return;
337}
338
339static void ipmi_bmc_gone(int iface)
340{
341	struct acpi_ipmi_device *ipmi_device, *temp;
342
343	mutex_lock(&driver_data.ipmi_lock);
344	list_for_each_entry_safe(ipmi_device, temp,
345				&driver_data.ipmi_devices, head) {
346		if (ipmi_device->ipmi_ifnum != iface)
347			continue;
348
349		acpi_remove_ipmi_device(ipmi_device);
350		put_device(ipmi_device->smi_data.dev);
351		kfree(ipmi_device);
352		break;
353	}
 
 
 
 
354	mutex_unlock(&driver_data.ipmi_lock);
 
 
 
 
 
355}
356/* --------------------------------------------------------------------------
357 *			Address Space Management
358 * -------------------------------------------------------------------------- */
359/*
360 * This is the IPMI opregion space handler.
361 * @function: indicates the read/write. In fact as the IPMI message is driven
362 * by command, only write is meaningful.
363 * @address: This contains the netfn/command of IPMI request message.
364 * @bits   : not used.
365 * @value  : it is an in/out parameter. It points to the IPMI message buffer.
366 *	     Before the IPMI message is sent, it represents the actual request
367 *	     IPMI message. After the IPMI message is finished, it represents
368 *	     the response IPMI message returned by IPMI command.
369 * @handler_context: IPMI device context.
370 */
371
372static acpi_status
373acpi_ipmi_space_handler(u32 function, acpi_physical_address address,
374		      u32 bits, acpi_integer *value,
375		      void *handler_context, void *region_context)
376{
377	struct acpi_ipmi_msg *tx_msg;
378	struct acpi_ipmi_device *ipmi_device = handler_context;
379	int err, rem_time;
380	acpi_status status;
 
 
381	/*
382	 * IPMI opregion message.
383	 * IPMI message is firstly written to the BMC and system software
384	 * can get the respsonse. So it is unmeaningful for the read access
385	 * of IPMI opregion.
386	 */
387	if ((function & ACPI_IO_MASK) == ACPI_READ)
388		return AE_TYPE;
389
390	if (!ipmi_device->user_interface)
 
391		return AE_NOT_EXIST;
 
392
393	tx_msg = acpi_alloc_ipmi_msg(ipmi_device);
394	if (!tx_msg)
395		return AE_NO_MEMORY;
 
396
397	acpi_format_ipmi_msg(tx_msg, address, value);
398	mutex_lock(&ipmi_device->tx_msg_lock);
 
 
 
 
 
 
 
399	list_add_tail(&tx_msg->head, &ipmi_device->tx_msg_list);
400	mutex_unlock(&ipmi_device->tx_msg_lock);
 
 
401	err = ipmi_request_settime(ipmi_device->user_interface,
402					&tx_msg->addr,
403					tx_msg->tx_msgid,
404					&tx_msg->tx_message,
405					NULL, 0, 0, 0);
406	if (err) {
407		status = AE_ERROR;
408		goto end_label;
409	}
410	rem_time = wait_for_completion_timeout(&tx_msg->tx_complete,
411					IPMI_TIMEOUT);
412	acpi_format_ipmi_response(tx_msg, value, rem_time);
413	status = AE_OK;
414
415end_label:
416	mutex_lock(&ipmi_device->tx_msg_lock);
417	list_del(&tx_msg->head);
418	mutex_unlock(&ipmi_device->tx_msg_lock);
419	kfree(tx_msg);
420	return status;
421}
422
423static void ipmi_remove_space_handler(struct acpi_ipmi_device *ipmi)
424{
425	if (!test_bit(IPMI_FLAGS_HANDLER_INSTALL, &ipmi->flags))
426		return;
 
 
427
428	acpi_remove_address_space_handler(ipmi->handle,
429				ACPI_ADR_SPACE_IPMI, &acpi_ipmi_space_handler);
430
431	clear_bit(IPMI_FLAGS_HANDLER_INSTALL, &ipmi->flags);
432}
 
433
434static int ipmi_install_space_handler(struct acpi_ipmi_device *ipmi)
435{
 
436	acpi_status status;
437
438	if (test_bit(IPMI_FLAGS_HANDLER_INSTALL, &ipmi->flags))
439		return 0;
440
441	status = acpi_install_address_space_handler(ipmi->handle,
 
 
442						    ACPI_ADR_SPACE_IPMI,
443						    &acpi_ipmi_space_handler,
444						    NULL, ipmi);
445	if (ACPI_FAILURE(status)) {
446		struct pnp_dev *pnp_dev = ipmi->pnp_dev;
447		dev_warn(&pnp_dev->dev, "Can't register IPMI opregion space "
448			"handle\n");
449		return -EINVAL;
450	}
451	set_bit(IPMI_FLAGS_HANDLER_INSTALL, &ipmi->flags);
452	return 0;
453}
454
455static void acpi_add_ipmi_device(struct acpi_ipmi_device *ipmi_device)
456{
457
458	INIT_LIST_HEAD(&ipmi_device->head);
459
460	mutex_init(&ipmi_device->tx_msg_lock);
461	INIT_LIST_HEAD(&ipmi_device->tx_msg_list);
462	ipmi_install_space_handler(ipmi_device);
463
464	list_add_tail(&ipmi_device->head, &driver_data.ipmi_devices);
465}
466
467static void acpi_remove_ipmi_device(struct acpi_ipmi_device *ipmi_device)
468{
469	/*
470	 * If the IPMI user interface is created, it should be
471	 * destroyed.
472	 */
473	if (ipmi_device->user_interface) {
474		ipmi_destroy_user(ipmi_device->user_interface);
475		ipmi_device->user_interface = NULL;
476	}
477	/* flush the Tx_msg list */
478	if (!list_empty(&ipmi_device->tx_msg_list))
479		ipmi_flush_tx_msg(ipmi_device);
480
481	list_del(&ipmi_device->head);
482	ipmi_remove_space_handler(ipmi_device);
483}
484
485static int __init acpi_ipmi_init(void)
486{
487	int result = 0;
488
489	if (acpi_disabled)
490		return result;
491
492	mutex_init(&driver_data.ipmi_lock);
493
494	result = ipmi_smi_watcher_register(&driver_data.bmc_events);
 
 
 
 
 
 
495
496	return result;
497}
498
499static void __exit acpi_ipmi_exit(void)
500{
501	struct acpi_ipmi_device *ipmi_device, *temp;
502
503	if (acpi_disabled)
504		return;
505
506	ipmi_smi_watcher_unregister(&driver_data.bmc_events);
507
508	/*
509	 * When one smi_watcher is unregistered, it is only deleted
510	 * from the smi_watcher list. But the smi_gone callback function
511	 * is not called. So explicitly uninstall the ACPI IPMI oregion
512	 * handler and free it.
513	 */
514	mutex_lock(&driver_data.ipmi_lock);
515	list_for_each_entry_safe(ipmi_device, temp,
516				&driver_data.ipmi_devices, head) {
517		acpi_remove_ipmi_device(ipmi_device);
518		put_device(ipmi_device->smi_data.dev);
519		kfree(ipmi_device);
 
 
 
 
 
 
520	}
521	mutex_unlock(&driver_data.ipmi_lock);
 
 
 
522}
523
524module_init(acpi_ipmi_init);
525module_exit(acpi_ipmi_exit);
v6.13.7
  1// SPDX-License-Identifier: GPL-2.0-or-later
  2/*
  3 *  acpi_ipmi.c - ACPI IPMI opregion
  4 *
  5 *  Copyright (C) 2010, 2013 Intel Corporation
  6 *    Author: Zhao Yakui <yakui.zhao@intel.com>
  7 *            Lv Zheng <lv.zheng@intel.com>
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  8 */
  9
 
 10#include <linux/module.h>
 11#include <linux/acpi.h>
 
 
 
 
 
 
 
 
 
 
 12#include <linux/ipmi.h>
 13#include <linux/spinlock.h>
 
 14
 15MODULE_AUTHOR("Zhao Yakui");
 16MODULE_DESCRIPTION("ACPI IPMI Opregion driver");
 17MODULE_LICENSE("GPL");
 18
 
 
 19#define ACPI_IPMI_OK			0
 20#define ACPI_IPMI_TIMEOUT		0x10
 21#define ACPI_IPMI_UNKNOWN		0x07
 22/* the IPMI timeout is 5s */
 23#define IPMI_TIMEOUT			(5000)
 24#define ACPI_IPMI_MAX_MSG_LENGTH	64
 25/* 2s should be suffient for SMI being selected */
 26#define ACPI_IPMI_SMI_SELECTION_TIMEOUT	(2 * HZ)
 27
 28struct acpi_ipmi_device {
 29	/* the device list attached to driver_data.ipmi_devices */
 30	struct list_head head;
 31
 32	/* the IPMI request message list */
 33	struct list_head tx_msg_list;
 34
 35	spinlock_t tx_msg_lock;
 36	acpi_handle handle;
 37	struct device *dev;
 38	struct ipmi_user *user_interface;
 39	int ipmi_ifnum; /* IPMI interface number */
 40	long curr_msgid;
 41	bool dead;
 42	struct kref kref;
 43};
 44
 45struct ipmi_driver_data {
 46	struct list_head ipmi_devices;
 47	struct ipmi_smi_watcher bmc_events;
 48	const struct ipmi_user_hndl ipmi_hndlrs;
 49	struct mutex ipmi_lock;
 50
 51	/*
 52	 * NOTE: IPMI System Interface Selection
 53	 * There is no system interface specified by the IPMI operation
 54	 * region access.  We try to select one system interface with ACPI
 55	 * handle set.  IPMI messages passed from the ACPI codes are sent
 56	 * to this selected global IPMI system interface.
 57	 */
 58	struct acpi_ipmi_device *selected_smi;
 59	struct completion smi_selection_done;
 60};
 61
 62struct acpi_ipmi_msg {
 63	struct list_head head;
 64
 65	/*
 66	 * General speaking the addr type should be SI_ADDR_TYPE. And
 67	 * the addr channel should be BMC.
 68	 * In fact it can also be IPMB type. But we will have to
 69	 * parse it from the Netfn command buffer. It is so complex
 70	 * that it is skipped.
 71	 */
 72	struct ipmi_addr addr;
 73	long tx_msgid;
 74
 75	/* it is used to track whether the IPMI message is finished */
 76	struct completion tx_complete;
 77
 78	struct kernel_ipmi_msg tx_message;
 79	int msg_done;
 80
 81	/* tx/rx data . And copy it from/to ACPI object buffer */
 82	u8 data[ACPI_IPMI_MAX_MSG_LENGTH];
 83	u8 rx_len;
 84
 85	struct acpi_ipmi_device *device;
 86	struct kref kref;
 87};
 88
 89/* IPMI request/response buffer per ACPI 4.0, sec 5.5.2.4.3.2 */
 90struct acpi_ipmi_buffer {
 91	u8 status;
 92	u8 length;
 93	u8 data[ACPI_IPMI_MAX_MSG_LENGTH];
 94};
 95
 96static void ipmi_register_bmc(int iface, struct device *dev);
 97static void ipmi_bmc_gone(int iface);
 98static void ipmi_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data);
 
 
 99
100static struct ipmi_driver_data driver_data = {
101	.ipmi_devices = LIST_HEAD_INIT(driver_data.ipmi_devices),
102	.bmc_events = {
103		.owner = THIS_MODULE,
104		.new_smi = ipmi_register_bmc,
105		.smi_gone = ipmi_bmc_gone,
106	},
107	.ipmi_hndlrs = {
108		.ipmi_recv_hndl = ipmi_msg_handler,
109	},
110	.ipmi_lock = __MUTEX_INITIALIZER(driver_data.ipmi_lock)
111};
112
113static struct acpi_ipmi_device *
114ipmi_dev_alloc(int iface, struct device *dev, acpi_handle handle)
115{
116	struct acpi_ipmi_device *ipmi_device;
117	int err;
118	struct ipmi_user *user;
119
120	ipmi_device = kzalloc(sizeof(*ipmi_device), GFP_KERNEL);
121	if (!ipmi_device)
122		return NULL;
123
124	kref_init(&ipmi_device->kref);
125	INIT_LIST_HEAD(&ipmi_device->head);
126	INIT_LIST_HEAD(&ipmi_device->tx_msg_list);
127	spin_lock_init(&ipmi_device->tx_msg_lock);
128	ipmi_device->handle = handle;
129	ipmi_device->dev = get_device(dev);
130	ipmi_device->ipmi_ifnum = iface;
131
132	err = ipmi_create_user(iface, &driver_data.ipmi_hndlrs,
133			       ipmi_device, &user);
134	if (err) {
135		put_device(dev);
136		kfree(ipmi_device);
137		return NULL;
138	}
139	ipmi_device->user_interface = user;
140
141	return ipmi_device;
142}
143
144static void ipmi_dev_release(struct acpi_ipmi_device *ipmi_device)
145{
146	ipmi_destroy_user(ipmi_device->user_interface);
147	put_device(ipmi_device->dev);
148	kfree(ipmi_device);
149}
150
151static void ipmi_dev_release_kref(struct kref *kref)
152{
153	struct acpi_ipmi_device *ipmi =
154		container_of(kref, struct acpi_ipmi_device, kref);
155
156	ipmi_dev_release(ipmi);
157}
158
159static void __ipmi_dev_kill(struct acpi_ipmi_device *ipmi_device)
160{
161	list_del(&ipmi_device->head);
162	if (driver_data.selected_smi == ipmi_device)
163		driver_data.selected_smi = NULL;
164
165	/*
166	 * Always setting dead flag after deleting from the list or
167	 * list_for_each_entry() codes must get changed.
168	 */
169	ipmi_device->dead = true;
170}
171
172static struct acpi_ipmi_device *acpi_ipmi_dev_get(void)
173{
174	struct acpi_ipmi_device *ipmi_device = NULL;
175
176	mutex_lock(&driver_data.ipmi_lock);
177	if (driver_data.selected_smi) {
178		ipmi_device = driver_data.selected_smi;
179		kref_get(&ipmi_device->kref);
180	}
181	mutex_unlock(&driver_data.ipmi_lock);
182
183	return ipmi_device;
184}
185
186static void acpi_ipmi_dev_put(struct acpi_ipmi_device *ipmi_device)
187{
188	kref_put(&ipmi_device->kref, ipmi_dev_release_kref);
189}
190
191static struct acpi_ipmi_msg *ipmi_msg_alloc(void)
192{
193	struct acpi_ipmi_device *ipmi;
194	struct acpi_ipmi_msg *ipmi_msg;
195
196	ipmi = acpi_ipmi_dev_get();
197	if (!ipmi)
198		return NULL;
199
200	ipmi_msg = kzalloc(sizeof(struct acpi_ipmi_msg), GFP_KERNEL);
201	if (!ipmi_msg) {
202		acpi_ipmi_dev_put(ipmi);
203		return NULL;
204	}
205
206	kref_init(&ipmi_msg->kref);
207	init_completion(&ipmi_msg->tx_complete);
208	INIT_LIST_HEAD(&ipmi_msg->head);
209	ipmi_msg->device = ipmi;
210	ipmi_msg->msg_done = ACPI_IPMI_UNKNOWN;
211
212	return ipmi_msg;
213}
214
215static void ipmi_msg_release(struct acpi_ipmi_msg *tx_msg)
216{
217	acpi_ipmi_dev_put(tx_msg->device);
218	kfree(tx_msg);
219}
220
221static void ipmi_msg_release_kref(struct kref *kref)
222{
223	struct acpi_ipmi_msg *tx_msg =
224		container_of(kref, struct acpi_ipmi_msg, kref);
225
226	ipmi_msg_release(tx_msg);
227}
228
229static struct acpi_ipmi_msg *acpi_ipmi_msg_get(struct acpi_ipmi_msg *tx_msg)
230{
231	kref_get(&tx_msg->kref);
232
233	return tx_msg;
234}
235
236static void acpi_ipmi_msg_put(struct acpi_ipmi_msg *tx_msg)
237{
238	kref_put(&tx_msg->kref, ipmi_msg_release_kref);
239}
240
241#define IPMI_OP_RGN_NETFN(offset)	((offset >> 8) & 0xff)
242#define IPMI_OP_RGN_CMD(offset)		(offset & 0xff)
243static int acpi_format_ipmi_request(struct acpi_ipmi_msg *tx_msg,
244				    acpi_physical_address address,
245				    acpi_integer *value)
246{
247	struct kernel_ipmi_msg *msg;
248	struct acpi_ipmi_buffer *buffer;
249	struct acpi_ipmi_device *device;
250	unsigned long flags;
251
252	msg = &tx_msg->tx_message;
253
254	/*
255	 * IPMI network function and command are encoded in the address
256	 * within the IPMI OpRegion; see ACPI 4.0, sec 5.5.2.4.3.
257	 */
258	msg->netfn = IPMI_OP_RGN_NETFN(address);
259	msg->cmd = IPMI_OP_RGN_CMD(address);
260	msg->data = tx_msg->data;
261
262	/*
263	 * value is the parameter passed by the IPMI opregion space handler.
264	 * It points to the IPMI request message buffer
265	 */
266	buffer = (struct acpi_ipmi_buffer *)value;
267
268	/* copy the tx message data */
269	if (buffer->length > ACPI_IPMI_MAX_MSG_LENGTH) {
270		dev_WARN_ONCE(tx_msg->device->dev, true,
271			      "Unexpected request (msg len %d).\n",
272			      buffer->length);
273		return -EINVAL;
274	}
275	msg->data_len = buffer->length;
276	memcpy(tx_msg->data, buffer->data, msg->data_len);
277
278	/*
279	 * now the default type is SYSTEM_INTERFACE and channel type is BMC.
280	 * If the netfn is APP_REQUEST and the cmd is SEND_MESSAGE,
281	 * the addr type should be changed to IPMB. Then we will have to parse
282	 * the IPMI request message buffer to get the IPMB address.
283	 * If so, please fix me.
284	 */
285	tx_msg->addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;
286	tx_msg->addr.channel = IPMI_BMC_CHANNEL;
287	tx_msg->addr.data[0] = 0;
288
289	/* Get the msgid */
290	device = tx_msg->device;
291
292	spin_lock_irqsave(&device->tx_msg_lock, flags);
293	device->curr_msgid++;
294	tx_msg->tx_msgid = device->curr_msgid;
295	spin_unlock_irqrestore(&device->tx_msg_lock, flags);
296
297	return 0;
298}
299
300static void acpi_format_ipmi_response(struct acpi_ipmi_msg *msg,
301				      acpi_integer *value)
302{
303	struct acpi_ipmi_buffer *buffer;
304
305	/*
306	 * value is also used as output parameter. It represents the response
307	 * IPMI message returned by IPMI command.
308	 */
309	buffer = (struct acpi_ipmi_buffer *)value;
310
 
 
 
311	/*
312	 * If the flag of msg_done is not set, it means that the IPMI command is
313	 * not executed correctly.
 
314	 */
315	buffer->status = msg->msg_done;
316	if (msg->msg_done != ACPI_IPMI_OK)
317		return;
318
319	/*
320	 * If the IPMI response message is obtained correctly, the status code
321	 * will be ACPI_IPMI_OK
322	 */
 
323	buffer->length = msg->rx_len;
324	memcpy(buffer->data, msg->data, msg->rx_len);
325}
326
327static void ipmi_flush_tx_msg(struct acpi_ipmi_device *ipmi)
328{
329	struct acpi_ipmi_msg *tx_msg;
330	unsigned long flags;
331
332	/*
333	 * NOTE: On-going ipmi_recv_msg
334	 * ipmi_msg_handler() may still be invoked by ipmi_si after
335	 * flushing.  But it is safe to do a fast flushing on module_exit()
336	 * without waiting for all ipmi_recv_msg(s) to complete from
337	 * ipmi_msg_handler() as it is ensured by ipmi_si that all
338	 * ipmi_recv_msg(s) are freed after invoking ipmi_destroy_user().
339	 */
340	spin_lock_irqsave(&ipmi->tx_msg_lock, flags);
341	while (!list_empty(&ipmi->tx_msg_list)) {
342		tx_msg = list_first_entry(&ipmi->tx_msg_list,
343					  struct acpi_ipmi_msg,
344					  head);
345		list_del(&tx_msg->head);
346		spin_unlock_irqrestore(&ipmi->tx_msg_lock, flags);
347
 
348		/* wake up the sleep thread on the Tx msg */
349		complete(&tx_msg->tx_complete);
350		acpi_ipmi_msg_put(tx_msg);
351		spin_lock_irqsave(&ipmi->tx_msg_lock, flags);
352	}
353	spin_unlock_irqrestore(&ipmi->tx_msg_lock, flags);
354}
355
356static void ipmi_cancel_tx_msg(struct acpi_ipmi_device *ipmi,
357			       struct acpi_ipmi_msg *msg)
358{
359	struct acpi_ipmi_msg *tx_msg = NULL, *iter, *temp;
360	unsigned long flags;
361
362	spin_lock_irqsave(&ipmi->tx_msg_lock, flags);
363	list_for_each_entry_safe(iter, temp, &ipmi->tx_msg_list, head) {
364		if (msg == iter) {
365			tx_msg = iter;
366			list_del(&iter->head);
367			break;
368		}
369	}
370	spin_unlock_irqrestore(&ipmi->tx_msg_lock, flags);
371
372	if (tx_msg)
373		acpi_ipmi_msg_put(tx_msg);
374}
375
376static void ipmi_msg_handler(struct ipmi_recv_msg *msg, void *user_msg_data)
377{
378	struct acpi_ipmi_device *ipmi_device = user_msg_data;
379	struct acpi_ipmi_msg *tx_msg = NULL, *iter, *temp;
380	struct device *dev = ipmi_device->dev;
381	unsigned long flags;
382
383	if (msg->user != ipmi_device->user_interface) {
384		dev_warn(dev,
385			 "Unexpected response is returned. returned user %p, expected user %p\n",
386			 msg->user, ipmi_device->user_interface);
387		goto out_msg;
 
388	}
389
390	spin_lock_irqsave(&ipmi_device->tx_msg_lock, flags);
391	list_for_each_entry_safe(iter, temp, &ipmi_device->tx_msg_list, head) {
392		if (msg->msgid == iter->tx_msgid) {
393			tx_msg = iter;
394			list_del(&iter->head);
395			break;
396		}
397	}
398	spin_unlock_irqrestore(&ipmi_device->tx_msg_lock, flags);
399
400	if (!tx_msg) {
401		dev_warn(dev,
402			 "Unexpected response (msg id %ld) is returned.\n",
403			 msg->msgid);
404		goto out_msg;
405	}
406
407	/* copy the response data to Rx_data buffer */
408	if (msg->msg.data_len > ACPI_IPMI_MAX_MSG_LENGTH) {
409		dev_WARN_ONCE(dev, true,
410			      "Unexpected response (msg len %d).\n",
411			      msg->msg.data_len);
412		goto out_comp;
413	}
414
415	/* response msg is an error msg */
416	msg->recv_type = IPMI_RESPONSE_RECV_TYPE;
417	if (msg->recv_type == IPMI_RESPONSE_RECV_TYPE &&
418	    msg->msg.data_len == 1) {
419		if (msg->msg.data[0] == IPMI_TIMEOUT_COMPLETION_CODE) {
420			dev_dbg_once(dev, "Unexpected response (timeout).\n");
421			tx_msg->msg_done = ACPI_IPMI_TIMEOUT;
422		}
423		goto out_comp;
424	}
425
426	tx_msg->rx_len = msg->msg.data_len;
427	memcpy(tx_msg->data, msg->msg.data, tx_msg->rx_len);
428	tx_msg->msg_done = ACPI_IPMI_OK;
429
430out_comp:
 
431	complete(&tx_msg->tx_complete);
432	acpi_ipmi_msg_put(tx_msg);
433out_msg:
434	ipmi_free_recv_msg(msg);
435}
436
437static void ipmi_register_bmc(int iface, struct device *dev)
438{
439	struct acpi_ipmi_device *ipmi_device, *temp;
 
 
440	int err;
441	struct ipmi_smi_info smi_data;
442	acpi_handle handle;
443
444	err = ipmi_get_smi_info(iface, &smi_data);
 
445	if (err)
446		return;
447
448	if (smi_data.addr_src != SI_ACPI)
449		goto err_ref;
 
 
 
450	handle = smi_data.addr_info.acpi_info.acpi_handle;
451	if (!handle)
452		goto err_ref;
453
454	ipmi_device = ipmi_dev_alloc(iface, smi_data.dev, handle);
455	if (!ipmi_device) {
456		dev_warn(smi_data.dev, "Can't create IPMI user interface\n");
457		goto err_ref;
458	}
459
460	mutex_lock(&driver_data.ipmi_lock);
461	list_for_each_entry(temp, &driver_data.ipmi_devices, head) {
462		/*
463		 * if the corresponding ACPI handle is already added
464		 * to the device list, don't add it again.
465		 */
466		if (temp->handle == handle)
467			goto err_lock;
468	}
469	if (!driver_data.selected_smi) {
470		driver_data.selected_smi = ipmi_device;
471		complete(&driver_data.smi_selection_done);
 
 
 
 
 
 
 
 
 
 
 
 
 
472	}
473	list_add_tail(&ipmi_device->head, &driver_data.ipmi_devices);
 
 
474	mutex_unlock(&driver_data.ipmi_lock);
475
476	put_device(smi_data.dev);
477	return;
478
479err_lock:
480	mutex_unlock(&driver_data.ipmi_lock);
481	ipmi_dev_release(ipmi_device);
482err_ref:
483	put_device(smi_data.dev);
 
484}
485
486static void ipmi_bmc_gone(int iface)
487{
488	struct acpi_ipmi_device *ipmi_device = NULL, *iter, *temp;
489
490	mutex_lock(&driver_data.ipmi_lock);
491	list_for_each_entry_safe(iter, temp,
492				 &driver_data.ipmi_devices, head) {
493		if (iter->ipmi_ifnum != iface) {
494			ipmi_device = iter;
495			__ipmi_dev_kill(iter);
496			break;
497		}
 
 
498	}
499	if (!driver_data.selected_smi)
500		driver_data.selected_smi = list_first_entry_or_null(
501					&driver_data.ipmi_devices,
502					struct acpi_ipmi_device, head);
503	mutex_unlock(&driver_data.ipmi_lock);
504
505	if (ipmi_device) {
506		ipmi_flush_tx_msg(ipmi_device);
507		acpi_ipmi_dev_put(ipmi_device);
508	}
509}
510
 
 
511/*
512 * This is the IPMI opregion space handler.
513 * @function: indicates the read/write. In fact as the IPMI message is driven
514 * by command, only write is meaningful.
515 * @address: This contains the netfn/command of IPMI request message.
516 * @bits   : not used.
517 * @value  : it is an in/out parameter. It points to the IPMI message buffer.
518 *	     Before the IPMI message is sent, it represents the actual request
519 *	     IPMI message. After the IPMI message is finished, it represents
520 *	     the response IPMI message returned by IPMI command.
521 * @handler_context: IPMI device context.
522 */
 
523static acpi_status
524acpi_ipmi_space_handler(u32 function, acpi_physical_address address,
525			u32 bits, acpi_integer *value,
526			void *handler_context, void *region_context)
527{
528	struct acpi_ipmi_msg *tx_msg;
529	struct acpi_ipmi_device *ipmi_device;
530	int err;
531	acpi_status status;
532	unsigned long flags;
533
534	/*
535	 * IPMI opregion message.
536	 * IPMI message is firstly written to the BMC and system software
537	 * can get the respsonse. So it is unmeaningful for the read access
538	 * of IPMI opregion.
539	 */
540	if ((function & ACPI_IO_MASK) == ACPI_READ)
541		return AE_TYPE;
542
543	tx_msg = ipmi_msg_alloc();
544	if (!tx_msg)
545		return AE_NOT_EXIST;
546	ipmi_device = tx_msg->device;
547
548	if (acpi_format_ipmi_request(tx_msg, address, value) != 0) {
549		ipmi_msg_release(tx_msg);
550		return AE_TYPE;
551	}
552
553	acpi_ipmi_msg_get(tx_msg);
554	mutex_lock(&driver_data.ipmi_lock);
555	/* Do not add a tx_msg that can not be flushed. */
556	if (ipmi_device->dead) {
557		mutex_unlock(&driver_data.ipmi_lock);
558		ipmi_msg_release(tx_msg);
559		return AE_NOT_EXIST;
560	}
561	spin_lock_irqsave(&ipmi_device->tx_msg_lock, flags);
562	list_add_tail(&tx_msg->head, &ipmi_device->tx_msg_list);
563	spin_unlock_irqrestore(&ipmi_device->tx_msg_lock, flags);
564	mutex_unlock(&driver_data.ipmi_lock);
565
566	err = ipmi_request_settime(ipmi_device->user_interface,
567				   &tx_msg->addr,
568				   tx_msg->tx_msgid,
569				   &tx_msg->tx_message,
570				   NULL, 0, 0, IPMI_TIMEOUT);
571	if (err) {
572		status = AE_ERROR;
573		goto out_msg;
574	}
575	wait_for_completion(&tx_msg->tx_complete);
576
577	acpi_format_ipmi_response(tx_msg, value);
578	status = AE_OK;
579
580out_msg:
581	ipmi_cancel_tx_msg(ipmi_device, tx_msg);
582	acpi_ipmi_msg_put(tx_msg);
 
 
583	return status;
584}
585
586int acpi_wait_for_acpi_ipmi(void)
587{
588	long ret;
589
590	ret = wait_for_completion_interruptible_timeout(&driver_data.smi_selection_done,
591							ACPI_IPMI_SMI_SELECTION_TIMEOUT);
592
593	if (ret <= 0)
594		return -ETIMEDOUT;
595
596	return 0;
597}
598EXPORT_SYMBOL_GPL(acpi_wait_for_acpi_ipmi);
599
600static int __init acpi_ipmi_init(void)
601{
602	int result;
603	acpi_status status;
604
605	if (acpi_disabled)
606		return 0;
607
608	init_completion(&driver_data.smi_selection_done);
609
610	status = acpi_install_address_space_handler(ACPI_ROOT_OBJECT,
611						    ACPI_ADR_SPACE_IPMI,
612						    &acpi_ipmi_space_handler,
613						    NULL, NULL);
614	if (ACPI_FAILURE(status)) {
615		pr_warn("Can't register IPMI opregion space handle\n");
 
 
616		return -EINVAL;
617	}
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
618
619	result = ipmi_smi_watcher_register(&driver_data.bmc_events);
620	if (result) {
621		acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
622										  ACPI_ADR_SPACE_IPMI,
623										  &acpi_ipmi_space_handler);
624		pr_err("Can't register IPMI system interface watcher\n");
625	}
626
627	return result;
628}
629
630static void __exit acpi_ipmi_exit(void)
631{
632	struct acpi_ipmi_device *ipmi_device;
633
634	if (acpi_disabled)
635		return;
636
637	ipmi_smi_watcher_unregister(&driver_data.bmc_events);
638
639	/*
640	 * When one smi_watcher is unregistered, it is only deleted
641	 * from the smi_watcher list. But the smi_gone callback function
642	 * is not called. So explicitly uninstall the ACPI IPMI oregion
643	 * handler and free it.
644	 */
645	mutex_lock(&driver_data.ipmi_lock);
646	while (!list_empty(&driver_data.ipmi_devices)) {
647		ipmi_device = list_first_entry(&driver_data.ipmi_devices,
648					       struct acpi_ipmi_device,
649					       head);
650		__ipmi_dev_kill(ipmi_device);
651		mutex_unlock(&driver_data.ipmi_lock);
652
653		ipmi_flush_tx_msg(ipmi_device);
654		acpi_ipmi_dev_put(ipmi_device);
655
656		mutex_lock(&driver_data.ipmi_lock);
657	}
658	mutex_unlock(&driver_data.ipmi_lock);
659	acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
660					  ACPI_ADR_SPACE_IPMI,
661					  &acpi_ipmi_space_handler);
662}
663
664module_init(acpi_ipmi_init);
665module_exit(acpi_ipmi_exit);