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 */
30 	/* the IPMI request message list */
37 	int ipmi_ifnum; /* IPMI interface number */
50 	 * NOTE: IPMI System Interface Selection
51 	 * There is no system interface specified by the IPMI operation
53 	 * handle set.  IPMI messages passed from the ACPI codes are sent
54 	 * to this selected global IPMI system interface.
65 	 * In fact it can also be IPMB type. But we will have to
72 	/* it is used to track whether the IPMI message is finished */
86 /* IPMI request/response buffer per ACPI 4.0, sec 5.5.2.4.3.2 */
121 	kref_init(&ipmi_device->kref);  in ipmi_dev_alloc()
122 	INIT_LIST_HEAD(&ipmi_device->head);  in ipmi_dev_alloc()
123 	INIT_LIST_HEAD(&ipmi_device->tx_msg_list);  in ipmi_dev_alloc()
124 	spin_lock_init(&ipmi_device->tx_msg_lock);  in ipmi_dev_alloc()
125 	ipmi_device->handle = handle;  in ipmi_dev_alloc()
126 	ipmi_device->dev = get_device(dev);  in ipmi_dev_alloc()
127 	ipmi_device->ipmi_ifnum = iface;  in ipmi_dev_alloc()
136 	ipmi_device->user_interface = user;  in ipmi_dev_alloc()
143 	ipmi_destroy_user(ipmi_device->user_interface);  in ipmi_dev_release()
144 	put_device(ipmi_device->dev);  in ipmi_dev_release()
150 	struct acpi_ipmi_device *ipmi =  in ipmi_dev_release_kref()  local
153 	ipmi_dev_release(ipmi);  in ipmi_dev_release_kref()
158 	list_del(&ipmi_device->head);  in __ipmi_dev_kill()
166 	ipmi_device->dead = true;  in __ipmi_dev_kill()
176 		kref_get(&ipmi_device->kref);  in acpi_ipmi_dev_get()
185 	kref_put(&ipmi_device->kref, ipmi_dev_release_kref);  in acpi_ipmi_dev_put()
190 	struct acpi_ipmi_device *ipmi;  in ipmi_msg_alloc()  local
193 	ipmi = acpi_ipmi_dev_get();  in ipmi_msg_alloc()
194 	if (!ipmi)  in ipmi_msg_alloc()
199 		acpi_ipmi_dev_put(ipmi);  in ipmi_msg_alloc()
203 	kref_init(&ipmi_msg->kref);  in ipmi_msg_alloc()
204 	init_completion(&ipmi_msg->tx_complete);  in ipmi_msg_alloc()
205 	INIT_LIST_HEAD(&ipmi_msg->head);  in ipmi_msg_alloc()
206 	ipmi_msg->device = ipmi;  in ipmi_msg_alloc()
207 	ipmi_msg->msg_done = ACPI_IPMI_UNKNOWN;  in ipmi_msg_alloc()
214 	acpi_ipmi_dev_put(tx_msg->device);  in ipmi_msg_release()
228 	kref_get(&tx_msg->kref);  in acpi_ipmi_msg_get()
235 	kref_put(&tx_msg->kref, ipmi_msg_release_kref);  in acpi_ipmi_msg_put()
249 	msg = &tx_msg->tx_message;  in acpi_format_ipmi_request()
252 	 * IPMI network function and command are encoded in the address  in acpi_format_ipmi_request()
253 	 * within the IPMI OpRegion; see ACPI 4.0, sec 5.5.2.4.3.  in acpi_format_ipmi_request()
255 	msg->netfn = IPMI_OP_RGN_NETFN(address);  in acpi_format_ipmi_request()
256 	msg->cmd = IPMI_OP_RGN_CMD(address);  in acpi_format_ipmi_request()
257 	msg->data = tx_msg->data;  in acpi_format_ipmi_request()
260 	 * value is the parameter passed by the IPMI opregion space handler.  in acpi_format_ipmi_request()
261 	 * It points to the IPMI request message buffer  in acpi_format_ipmi_request()
266 	if (buffer->length > ACPI_IPMI_MAX_MSG_LENGTH) {  in acpi_format_ipmi_request()
267 		dev_WARN_ONCE(tx_msg->device->dev, true,  in acpi_format_ipmi_request()
269 			      buffer->length);  in acpi_format_ipmi_request()
270 		return -EINVAL;  in acpi_format_ipmi_request()
272 	msg->data_len = buffer->length;  in acpi_format_ipmi_request()
273 	memcpy(tx_msg->data, buffer->data, msg->data_len);  in acpi_format_ipmi_request()
278 	 * the addr type should be changed to IPMB. Then we will have to parse  in acpi_format_ipmi_request()
279 	 * the IPMI request message buffer to get the IPMB address.  in acpi_format_ipmi_request()
282 	tx_msg->addr.addr_type = IPMI_SYSTEM_INTERFACE_ADDR_TYPE;  in acpi_format_ipmi_request()
283 	tx_msg->addr.channel = IPMI_BMC_CHANNEL;  in acpi_format_ipmi_request()
284 	tx_msg->addr.data[0] = 0;  in acpi_format_ipmi_request()
287 	device = tx_msg->device;  in acpi_format_ipmi_request()
289 	spin_lock_irqsave(&device->tx_msg_lock, flags);  in acpi_format_ipmi_request()
290 	device->curr_msgid++;  in acpi_format_ipmi_request()
291 	tx_msg->tx_msgid = device->curr_msgid;  in acpi_format_ipmi_request()
292 	spin_unlock_irqrestore(&device->tx_msg_lock, flags);  in acpi_format_ipmi_request()
304 	 * IPMI message returned by IPMI command.  in acpi_format_ipmi_response()
309 	 * If the flag of msg_done is not set, it means that the IPMI command is  in acpi_format_ipmi_response()
312 	buffer->status = msg->msg_done;  in acpi_format_ipmi_response()
313 	if (msg->msg_done != ACPI_IPMI_OK)  in acpi_format_ipmi_response()
317 	 * If the IPMI response message is obtained correctly, the status code  in acpi_format_ipmi_response()
320 	buffer->length = msg->rx_len;  in acpi_format_ipmi_response()
321 	memcpy(buffer->data, msg->data, msg->rx_len);  in acpi_format_ipmi_response()
324 static void ipmi_flush_tx_msg(struct acpi_ipmi_device *ipmi)  in ipmi_flush_tx_msg()  argument
330 	 * NOTE: On-going ipmi_recv_msg  in ipmi_flush_tx_msg()
337 	spin_lock_irqsave(&ipmi->tx_msg_lock, flags);  in ipmi_flush_tx_msg()
338 	while (!list_empty(&ipmi->tx_msg_list)) {  in ipmi_flush_tx_msg()
339 		tx_msg = list_first_entry(&ipmi->tx_msg_list,  in ipmi_flush_tx_msg()
342 		list_del(&tx_msg->head);  in ipmi_flush_tx_msg()
343 		spin_unlock_irqrestore(&ipmi->tx_msg_lock, flags);  in ipmi_flush_tx_msg()
346 		complete(&tx_msg->tx_complete);  in ipmi_flush_tx_msg()
348 		spin_lock_irqsave(&ipmi->tx_msg_lock, flags);  in ipmi_flush_tx_msg()
350 	spin_unlock_irqrestore(&ipmi->tx_msg_lock, flags);  in ipmi_flush_tx_msg()
353 static void ipmi_cancel_tx_msg(struct acpi_ipmi_device *ipmi,  in ipmi_cancel_tx_msg()  argument
359 	spin_lock_irqsave(&ipmi->tx_msg_lock, flags);  in ipmi_cancel_tx_msg()
360 	list_for_each_entry_safe(iter, temp, &ipmi->tx_msg_list, head) {  in ipmi_cancel_tx_msg()
363 			list_del(&iter->head);  in ipmi_cancel_tx_msg()
367 	spin_unlock_irqrestore(&ipmi->tx_msg_lock, flags);  in ipmi_cancel_tx_msg()
377 	struct device *dev = ipmi_device->dev;  in ipmi_msg_handler()
380 	if (msg->user != ipmi_device->user_interface) {  in ipmi_msg_handler()
383 			 msg->user, ipmi_device->user_interface);  in ipmi_msg_handler()
387 	spin_lock_irqsave(&ipmi_device->tx_msg_lock, flags);  in ipmi_msg_handler()
388 	list_for_each_entry_safe(iter, temp, &ipmi_device->tx_msg_list, head) {  in ipmi_msg_handler()
389 		if (msg->msgid == iter->tx_msgid) {  in ipmi_msg_handler()
391 			list_del(&iter->head);  in ipmi_msg_handler()
395 	spin_unlock_irqrestore(&ipmi_device->tx_msg_lock, flags);  in ipmi_msg_handler()
400 			 msg->msgid);  in ipmi_msg_handler()
405 	if (msg->msg.data_len > ACPI_IPMI_MAX_MSG_LENGTH) {  in ipmi_msg_handler()
408 			      msg->msg.data_len);  in ipmi_msg_handler()
413 	msg->recv_type = IPMI_RESPONSE_RECV_TYPE;  in ipmi_msg_handler()
414 	if (msg->recv_type == IPMI_RESPONSE_RECV_TYPE &&  in ipmi_msg_handler()
415 	    msg->msg.data_len == 1) {  in ipmi_msg_handler()
416 		if (msg->msg.data[0] == IPMI_TIMEOUT_COMPLETION_CODE) {  in ipmi_msg_handler()
418 			tx_msg->msg_done = ACPI_IPMI_TIMEOUT;  in ipmi_msg_handler()
423 	tx_msg->rx_len = msg->msg.data_len;  in ipmi_msg_handler()
424 	memcpy(tx_msg->data, msg->msg.data, tx_msg->rx_len);  in ipmi_msg_handler()
425 	tx_msg->msg_done = ACPI_IPMI_OK;  in ipmi_msg_handler()
428 	complete(&tx_msg->tx_complete);  in ipmi_msg_handler()
453 		dev_warn(smi_data.dev, "Can't create IPMI user interface\n");  in ipmi_register_bmc()
463 		if (temp->handle == handle)  in ipmi_register_bmc()
468 	list_add_tail(&ipmi_device->head, &driver_data.ipmi_devices);  in ipmi_register_bmc()
488 		if (iter->ipmi_ifnum != iface) {  in ipmi_bmc_gone()
507  * This is the IPMI opregion space handler.
508  * @function: indicates the read/write. In fact as the IPMI message is driven
510  * @address: This contains the netfn/command of IPMI request message.
512  * @value  : it is an in/out parameter. It points to the IPMI message buffer.
513  *	     Before the IPMI message is sent, it represents the actual request
514  *	     IPMI message. After the IPMI message is finished, it represents
515  *	     the response IPMI message returned by IPMI command.
516  * @handler_context: IPMI device context.
530 	 * IPMI opregion message.  in acpi_ipmi_space_handler()
531 	 * IPMI message is firstly written to the BMC and system software  in acpi_ipmi_space_handler()
533 	 * of IPMI opregion.  in acpi_ipmi_space_handler()
541 	ipmi_device = tx_msg->device;  in acpi_ipmi_space_handler()
551 	if (ipmi_device->dead) {  in acpi_ipmi_space_handler()
556 	spin_lock_irqsave(&ipmi_device->tx_msg_lock, flags);  in acpi_ipmi_space_handler()
557 	list_add_tail(&tx_msg->head, &ipmi_device->tx_msg_list);  in acpi_ipmi_space_handler()
558 	spin_unlock_irqrestore(&ipmi_device->tx_msg_lock, flags);  in acpi_ipmi_space_handler()
561 	err = ipmi_request_settime(ipmi_device->user_interface,  in acpi_ipmi_space_handler()
562 				   &tx_msg->addr,  in acpi_ipmi_space_handler()
563 				   tx_msg->tx_msgid,  in acpi_ipmi_space_handler()
564 				   &tx_msg->tx_message,  in acpi_ipmi_space_handler()
570 	wait_for_completion(&tx_msg->tx_complete);  in acpi_ipmi_space_handler()
594 		pr_warn("Can't register IPMI opregion space handle\n");  in acpi_ipmi_init()
595 		return -EINVAL;  in acpi_ipmi_init()
603 		pr_err("Can't register IPMI system interface watcher\n");  in acpi_ipmi_init()
621 	 * is not called. So explicitly uninstall the ACPI IPMI oregion  in acpi_ipmi_exit()