1 // SPDX-License-Identifier: GPL-2.0-or-later
3  *  acpi_ipmi.c - ACPI IPMI opregion
12 #include <linux/ipmi.h>
16 MODULE_DESCRIPTION("ACPI IPMI Opregion driver");
22 /* the IPMI timeout is 5s */
32 	/* the IPMI request message list */
39 	int ipmi_ifnum; /* IPMI interface number */
52 	 * NOTE: IPMI System Interface Selection
53 	 * There is no system interface specified by the IPMI operation
55 	 * handle set.  IPMI messages passed from the ACPI codes are sent
56 	 * to this selected global IPMI system interface.
68 	 * In fact it can also be IPMB type. But we will have to
75 	/* it is used to track whether the IPMI message is finished */
89 /* IPMI request/response buffer per ACPI 4.0, sec 5.5.2.4.3.2 */
124 	kref_init(&ipmi_device->kref);  in ipmi_dev_alloc()
125 	INIT_LIST_HEAD(&ipmi_device->head);  in ipmi_dev_alloc()
126 	INIT_LIST_HEAD(&ipmi_device->tx_msg_list);  in ipmi_dev_alloc()
127 	spin_lock_init(&ipmi_device->tx_msg_lock);  in ipmi_dev_alloc()
128 	ipmi_device->handle = handle;  in ipmi_dev_alloc()
129 	ipmi_device->dev = get_device(dev);  in ipmi_dev_alloc()
130 	ipmi_device->ipmi_ifnum = iface;  in ipmi_dev_alloc()
139 	ipmi_device->user_interface = user;  in ipmi_dev_alloc()
146 	ipmi_destroy_user(ipmi_device->user_interface);  in ipmi_dev_release()
147 	put_device(ipmi_device->dev);  in ipmi_dev_release()
153 	struct acpi_ipmi_device *ipmi =  in ipmi_dev_release_kref()  local
156 	ipmi_dev_release(ipmi);  in ipmi_dev_release_kref()
161 	list_del(&ipmi_device->head);  in __ipmi_dev_kill()
169 	ipmi_device->dead = true;  in __ipmi_dev_kill()
179 		kref_get(&ipmi_device->kref);  in acpi_ipmi_dev_get()
188 	kref_put(&ipmi_device->kref, ipmi_dev_release_kref);  in acpi_ipmi_dev_put()
193 	struct acpi_ipmi_device *ipmi;  in ipmi_msg_alloc()  local
196 	ipmi = acpi_ipmi_dev_get();  in ipmi_msg_alloc()
197 	if (!ipmi)  in ipmi_msg_alloc()
202 		acpi_ipmi_dev_put(ipmi);  in ipmi_msg_alloc()
206 	kref_init(&ipmi_msg->kref);  in ipmi_msg_alloc()
207 	init_completion(&ipmi_msg->tx_complete);  in ipmi_msg_alloc()
208 	INIT_LIST_HEAD(&ipmi_msg->head);  in ipmi_msg_alloc()
209 	ipmi_msg->device = ipmi;  in ipmi_msg_alloc()
210 	ipmi_msg->msg_done = ACPI_IPMI_UNKNOWN;  in ipmi_msg_alloc()
217 	acpi_ipmi_dev_put(tx_msg->device);  in ipmi_msg_release()
231 	kref_get(&tx_msg->kref);  in acpi_ipmi_msg_get()
238 	kref_put(&tx_msg->kref, ipmi_msg_release_kref);  in acpi_ipmi_msg_put()
252 	msg = &tx_msg->tx_message;  in acpi_format_ipmi_request()
255 	 * IPMI network function and command are encoded in the address  in acpi_format_ipmi_request()
256 	 * within the IPMI OpRegion; see ACPI 4.0, sec 5.5.2.4.3.  in acpi_format_ipmi_request()
258 	msg->netfn = IPMI_OP_RGN_NETFN(address);  in acpi_format_ipmi_request()
259 	msg->cmd = IPMI_OP_RGN_CMD(address);  in acpi_format_ipmi_request()
260 	msg->data = tx_msg->data;  in acpi_format_ipmi_request()
263 	 * value is the parameter passed by the IPMI opregion space handler.  in acpi_format_ipmi_request()
264 	 * It points to the IPMI request message buffer  in acpi_format_ipmi_request()
269 	if (buffer->length > ACPI_IPMI_MAX_MSG_LENGTH) {  in acpi_format_ipmi_request()
270 		dev_WARN_ONCE(tx_msg->device->dev, true,  in acpi_format_ipmi_request()
272 			      buffer->length);  in acpi_format_ipmi_request()
273 		return -EINVAL;  in acpi_format_ipmi_request()
275 	msg->data_len = buffer->length;  in acpi_format_ipmi_request()
276 	memcpy(tx_msg->data, buffer->data, msg->data_len);  in acpi_format_ipmi_request()
281 	 * the addr type should be changed to IPMB. Then we will have to parse  in acpi_format_ipmi_request()
282 	 * the IPMI request message buffer to get the IPMB address.  in acpi_format_ipmi_request()
285 	tx_msg->addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;  in acpi_format_ipmi_request()
286 	tx_msg->addr.channel = IPMI_BMC_CHANNEL;  in acpi_format_ipmi_request()
287 	tx_msg->addr.data[0] = 0;  in acpi_format_ipmi_request()
290 	device = tx_msg->device;  in acpi_format_ipmi_request()
292 	spin_lock_irqsave(&device->tx_msg_lock, flags);  in acpi_format_ipmi_request()
293 	device->curr_msgid++;  in acpi_format_ipmi_request()
294 	tx_msg->tx_msgid = device->curr_msgid;  in acpi_format_ipmi_request()
295 	spin_unlock_irqrestore(&device->tx_msg_lock, flags);  in acpi_format_ipmi_request()
307 	 * IPMI message returned by IPMI command.  in acpi_format_ipmi_response()
312 	 * If the flag of msg_done is not set, it means that the IPMI command is  in acpi_format_ipmi_response()
315 	buffer->status = msg->msg_done;  in acpi_format_ipmi_response()
316 	if (msg->msg_done != ACPI_IPMI_OK)  in acpi_format_ipmi_response()
320 	 * If the IPMI response message is obtained correctly, the status code  in acpi_format_ipmi_response()
323 	buffer->length = msg->rx_len;  in acpi_format_ipmi_response()
324 	memcpy(buffer->data, msg->data, msg->rx_len);  in acpi_format_ipmi_response()
327 static void ipmi_flush_tx_msg(struct acpi_ipmi_device *ipmi)  in ipmi_flush_tx_msg()  argument
333 	 * NOTE: On-going ipmi_recv_msg  in ipmi_flush_tx_msg()
340 	spin_lock_irqsave(&ipmi->tx_msg_lock, flags);  in ipmi_flush_tx_msg()
341 	while (!list_empty(&ipmi->tx_msg_list)) {  in ipmi_flush_tx_msg()
342 		tx_msg = list_first_entry(&ipmi->tx_msg_list,  in ipmi_flush_tx_msg()
345 		list_del(&tx_msg->head);  in ipmi_flush_tx_msg()
346 		spin_unlock_irqrestore(&ipmi->tx_msg_lock, flags);  in ipmi_flush_tx_msg()
349 		complete(&tx_msg->tx_complete);  in ipmi_flush_tx_msg()
351 		spin_lock_irqsave(&ipmi->tx_msg_lock, flags);  in ipmi_flush_tx_msg()
353 	spin_unlock_irqrestore(&ipmi->tx_msg_lock, flags);  in ipmi_flush_tx_msg()
356 static void ipmi_cancel_tx_msg(struct acpi_ipmi_device *ipmi,  in ipmi_cancel_tx_msg()  argument
362 	spin_lock_irqsave(&ipmi->tx_msg_lock, flags);  in ipmi_cancel_tx_msg()
363 	list_for_each_entry_safe(iter, temp, &ipmi->tx_msg_list, head) {  in ipmi_cancel_tx_msg()
366 			list_del(&iter->head);  in ipmi_cancel_tx_msg()
370 	spin_unlock_irqrestore(&ipmi->tx_msg_lock, flags);  in ipmi_cancel_tx_msg()
380 	struct device *dev = ipmi_device->dev;  in ipmi_msg_handler()
383 	if (msg->user != ipmi_device->user_interface) {  in ipmi_msg_handler()
386 			 msg->user, ipmi_device->user_interface);  in ipmi_msg_handler()
390 	spin_lock_irqsave(&ipmi_device->tx_msg_lock, flags);  in ipmi_msg_handler()
391 	list_for_each_entry_safe(iter, temp, &ipmi_device->tx_msg_list, head) {  in ipmi_msg_handler()
392 		if (msg->msgid == iter->tx_msgid) {  in ipmi_msg_handler()
394 			list_del(&iter->head);  in ipmi_msg_handler()
398 	spin_unlock_irqrestore(&ipmi_device->tx_msg_lock, flags);  in ipmi_msg_handler()
403 			 msg->msgid);  in ipmi_msg_handler()
408 	if (msg->msg.data_len > ACPI_IPMI_MAX_MSG_LENGTH) {  in ipmi_msg_handler()
411 			      msg->msg.data_len);  in ipmi_msg_handler()
416 	msg->recv_type = IPMI_RESPONSE_RECV_TYPE;  in ipmi_msg_handler()
417 	if (msg->recv_type == IPMI_RESPONSE_RECV_TYPE &&  in ipmi_msg_handler()
418 	    msg->msg.data_len == 1) {  in ipmi_msg_handler()
419 		if (msg->msg.data[0] == IPMI_TIMEOUT_COMPLETION_CODE) {  in ipmi_msg_handler()
421 			tx_msg->msg_done = ACPI_IPMI_TIMEOUT;  in ipmi_msg_handler()
426 	tx_msg->rx_len = msg->msg.data_len;  in ipmi_msg_handler()
427 	memcpy(tx_msg->data, msg->msg.data, tx_msg->rx_len);  in ipmi_msg_handler()
428 	tx_msg->msg_done = ACPI_IPMI_OK;  in ipmi_msg_handler()
431 	complete(&tx_msg->tx_complete);  in ipmi_msg_handler()
456 		dev_warn(smi_data.dev, "Can't create IPMI user interface\n");  in ipmi_register_bmc()
466 		if (temp->handle == handle)  in ipmi_register_bmc()
473 	list_add_tail(&ipmi_device->head, &driver_data.ipmi_devices);  in ipmi_register_bmc()
493 		if (iter->ipmi_ifnum != iface) {  in ipmi_bmc_gone()
512  * This is the IPMI opregion space handler.
513  * @function: indicates the read/write. In fact as the IPMI message is driven
515  * @address: This contains the netfn/command of IPMI request message.
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.
535 	 * IPMI opregion message.  in acpi_ipmi_space_handler()
536 	 * IPMI message is firstly written to the BMC and system software  in acpi_ipmi_space_handler()
538 	 * of IPMI opregion.  in acpi_ipmi_space_handler()
546 	ipmi_device = tx_msg->device;  in acpi_ipmi_space_handler()
556 	if (ipmi_device->dead) {  in acpi_ipmi_space_handler()
561 	spin_lock_irqsave(&ipmi_device->tx_msg_lock, flags);  in acpi_ipmi_space_handler()
562 	list_add_tail(&tx_msg->head, &ipmi_device->tx_msg_list);  in acpi_ipmi_space_handler()
563 	spin_unlock_irqrestore(&ipmi_device->tx_msg_lock, flags);  in acpi_ipmi_space_handler()
566 	err = ipmi_request_settime(ipmi_device->user_interface,  in acpi_ipmi_space_handler()
567 				   &tx_msg->addr,  in acpi_ipmi_space_handler()
568 				   tx_msg->tx_msgid,  in acpi_ipmi_space_handler()
569 				   &tx_msg->tx_message,  in acpi_ipmi_space_handler()
575 	wait_for_completion(&tx_msg->tx_complete);  in acpi_ipmi_space_handler()
594 		return -ETIMEDOUT;  in acpi_wait_for_acpi_ipmi()
615 		pr_warn("Can't register IPMI opregion space handle\n");  in acpi_ipmi_init()
616 		return -EINVAL;  in acpi_ipmi_init()
624 		pr_err("Can't register IPMI system interface watcher\n");  in acpi_ipmi_init()
642 	 * is not called. So explicitly uninstall the ACPI IPMI oregion  in acpi_ipmi_exit()