1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * ipmi_smi.h
4  *
5  * MontaVista IPMI system management interface
6  *
7  * Author: MontaVista Software, Inc.
8  *         Corey Minyard <minyard@mvista.com>
9  *         source@mvista.com
10  *
11  * Copyright 2002 MontaVista Software Inc.
12  *
13  */
14 
15 #ifndef __LINUX_IPMI_SMI_H
16 #define __LINUX_IPMI_SMI_H
17 
18 #include <linux/ipmi_msgdefs.h>
19 #include <linux/proc_fs.h>
20 #include <linux/platform_device.h>
21 #include <linux/ipmi.h>
22 
23 struct device;
24 
25 /*
26  * This files describes the interface for IPMI system management interface
27  * drivers to bind into the IPMI message handler.
28  */
29 
30 /* Structure for the low-level drivers. */
31 struct ipmi_smi;
32 
33 /*
34  * Flags for set_check_watch() below.  Tells if the SMI should be
35  * waiting for watchdog timeouts, commands and/or messages.
36  */
37 #define IPMI_WATCH_MASK_CHECK_MESSAGES	(1 << 0)
38 #define IPMI_WATCH_MASK_CHECK_WATCHDOG	(1 << 1)
39 #define IPMI_WATCH_MASK_CHECK_COMMANDS	(1 << 2)
40 
41 /*
42  * SMI messages
43  *
44  * When communicating with an SMI, messages come in two formats:
45  *
46  * * Normal (to a BMC over a BMC interface)
47  *
48  * * IPMB (over a IPMB to another MC)
49  *
50  * When normal, commands are sent using the format defined by a
51  * standard message over KCS (NetFn must be even):
52  *
53  *   +-----------+-----+------+
54  *   | NetFn/LUN | Cmd | Data |
55  *   +-----------+-----+------+
56  *
57  * And responses, similarly, with an completion code added (NetFn must
58  * be odd):
59  *
60  *   +-----------+-----+------+------+
61  *   | NetFn/LUN | Cmd | CC   | Data |
62  *   +-----------+-----+------+------+
63  *
64  * With normal messages, only commands are sent and only responses are
65  * received.
66  *
67  * In IPMB mode, we are acting as an IPMB device. Commands will be in
68  * the following format (NetFn must be even):
69  *
70  *   +-------------+------+-------------+-----+------+
71  *   | NetFn/rsLUN | Addr | rqSeq/rqLUN | Cmd | Data |
72  *   +-------------+------+-------------+-----+------+
73  *
74  * Responses will using the following format:
75  *
76  *   +-------------+------+-------------+-----+------+------+
77  *   | NetFn/rqLUN | Addr | rqSeq/rsLUN | Cmd | CC   | Data |
78  *   +-------------+------+-------------+-----+------+------+
79  *
80  * This is similar to the format defined in the IPMB manual section
81  * 2.11.1 with the checksums and the first address removed.  Also, the
82  * address is always the remote address.
83  *
84  * IPMB messages can be commands and responses in both directions.
85  * Received commands are handled as received commands from the message
86  * queue.
87  */
88 
89 enum ipmi_smi_msg_type {
90 	IPMI_SMI_MSG_TYPE_NORMAL = 0,
91 	IPMI_SMI_MSG_TYPE_IPMB_DIRECT
92 };
93 
94 /*
95  * Messages to/from the lower layer.  The smi interface will take one
96  * of these to send. After the send has occurred and a response has
97  * been received, it will report this same data structure back up to
98  * the upper layer.  If an error occurs, it should fill in the
99  * response with an error code in the completion code location. When
100  * asynchronous data is received, one of these is allocated, the
101  * data_size is set to zero and the response holds the data from the
102  * get message or get event command that the interface initiated.
103  * Note that it is the interfaces responsibility to detect
104  * asynchronous data and messages and request them from the
105  * interface.
106  */
107 struct ipmi_smi_msg {
108 	struct list_head link;
109 
110 	enum ipmi_smi_msg_type type;
111 
112 	long    msgid;
113 	void    *user_data;
114 
115 	int           data_size;
116 	unsigned char data[IPMI_MAX_MSG_LENGTH];
117 
118 	int           rsp_size;
119 	unsigned char rsp[IPMI_MAX_MSG_LENGTH];
120 
121 	/*
122 	 * Will be called when the system is done with the message
123 	 * (presumably to free it).
124 	 */
125 	void (*done)(struct ipmi_smi_msg *msg);
126 };
127 
128 #define INIT_IPMI_SMI_MSG(done_handler) \
129 {						\
130 	.done = done_handler,			\
131 	.type = IPMI_SMI_MSG_TYPE_NORMAL	\
132 }
133 
134 struct ipmi_smi_handlers {
135 	struct module *owner;
136 
137 	/* Capabilities of the SMI. */
138 #define IPMI_SMI_CAN_HANDLE_IPMB_DIRECT		(1 << 0)
139 	unsigned int flags;
140 
141 	/*
142 	 * The low-level interface cannot start sending messages to
143 	 * the upper layer until this function is called.  This may
144 	 * not be NULL, the lower layer must take the interface from
145 	 * this call.
146 	 */
147 	int (*start_processing)(void            *send_info,
148 				struct ipmi_smi *new_intf);
149 
150 	/*
151 	 * When called, the low-level interface should disable all
152 	 * processing, it should be complete shut down when it returns.
153 	 */
154 	void (*shutdown)(void *send_info);
155 
156 	/*
157 	 * Get the detailed private info of the low level interface and store
158 	 * it into the structure of ipmi_smi_data. For example: the
159 	 * ACPI device handle will be returned for the pnp_acpi IPMI device.
160 	 */
161 	int (*get_smi_info)(void *send_info, struct ipmi_smi_info *data);
162 
163 	/*
164 	 * Called to enqueue an SMI message to be sent.  This
165 	 * operation is not allowed to fail.  If an error occurs, it
166 	 * should report back the error in a received message.  It may
167 	 * do this in the current call context, since no write locks
168 	 * are held when this is run.  Message are delivered one at
169 	 * a time by the message handler, a new message will not be
170 	 * delivered until the previous message is returned.
171 	 */
172 	void (*sender)(void                *send_info,
173 		       struct ipmi_smi_msg *msg);
174 
175 	/*
176 	 * Called by the upper layer to request that we try to get
177 	 * events from the BMC we are attached to.
178 	 */
179 	void (*request_events)(void *send_info);
180 
181 	/*
182 	 * Called by the upper layer when some user requires that the
183 	 * interface watch for received messages and watchdog
184 	 * pretimeouts (basically do a "Get Flags", or not.  Used by
185 	 * the SMI to know if it should watch for these.  This may be
186 	 * NULL if the SMI does not implement it.  watch_mask is from
187 	 * IPMI_WATCH_MASK_xxx above.  The interface should run slower
188 	 * timeouts for just watchdog checking or faster timeouts when
189 	 * waiting for the message queue.
190 	 */
191 	void (*set_need_watch)(void *send_info, unsigned int watch_mask);
192 
193 	/*
194 	 * Called when flushing all pending messages.
195 	 */
196 	void (*flush_messages)(void *send_info);
197 
198 	/*
199 	 * Called when the interface should go into "run to
200 	 * completion" mode.  If this call sets the value to true, the
201 	 * interface should make sure that all messages are flushed
202 	 * out and that none are pending, and any new requests are run
203 	 * to completion immediately.
204 	 */
205 	void (*set_run_to_completion)(void *send_info, bool run_to_completion);
206 
207 	/*
208 	 * Called to poll for work to do.  This is so upper layers can
209 	 * poll for operations during things like crash dumps.
210 	 */
211 	void (*poll)(void *send_info);
212 
213 	/*
214 	 * Enable/disable firmware maintenance mode.  Note that this
215 	 * is *not* the modes defined, this is simply an on/off
216 	 * setting.  The message handler does the mode handling.  Note
217 	 * that this is called from interrupt context, so it cannot
218 	 * block.
219 	 */
220 	void (*set_maintenance_mode)(void *send_info, bool enable);
221 };
222 
223 struct ipmi_device_id {
224 	unsigned char device_id;
225 	unsigned char device_revision;
226 	unsigned char firmware_revision_1;
227 	unsigned char firmware_revision_2;
228 	unsigned char ipmi_version;
229 	unsigned char additional_device_support;
230 	unsigned int  manufacturer_id;
231 	unsigned int  product_id;
232 	unsigned char aux_firmware_revision[4];
233 	unsigned int  aux_firmware_revision_set : 1;
234 };
235 
236 #define ipmi_version_major(v) ((v)->ipmi_version & 0xf)
237 #define ipmi_version_minor(v) ((v)->ipmi_version >> 4)
238 
239 /*
240  * Take a pointer to an IPMI response and extract device id information from
241  * it. @netfn is in the IPMI_NETFN_ format, so may need to be shifted from
242  * a SI response.
243  */
ipmi_demangle_device_id(uint8_t netfn,uint8_t cmd,const unsigned char * data,unsigned int data_len,struct ipmi_device_id * id)244 static inline int ipmi_demangle_device_id(uint8_t netfn, uint8_t cmd,
245 					  const unsigned char *data,
246 					  unsigned int data_len,
247 					  struct ipmi_device_id *id)
248 {
249 	if (data_len < 7)
250 		return -EINVAL;
251 	if (netfn != IPMI_NETFN_APP_RESPONSE || cmd != IPMI_GET_DEVICE_ID_CMD)
252 		/* Strange, didn't get the response we expected. */
253 		return -EINVAL;
254 	if (data[0] != 0)
255 		/* That's odd, it shouldn't be able to fail. */
256 		return -EINVAL;
257 
258 	data++;
259 	data_len--;
260 
261 	id->device_id = data[0];
262 	id->device_revision = data[1];
263 	id->firmware_revision_1 = data[2];
264 	id->firmware_revision_2 = data[3];
265 	id->ipmi_version = data[4];
266 	id->additional_device_support = data[5];
267 	if (data_len >= 11) {
268 		id->manufacturer_id = (data[6] | (data[7] << 8) |
269 				       (data[8] << 16));
270 		id->product_id = data[9] | (data[10] << 8);
271 	} else {
272 		id->manufacturer_id = 0;
273 		id->product_id = 0;
274 	}
275 	if (data_len >= 15) {
276 		memcpy(id->aux_firmware_revision, data+11, 4);
277 		id->aux_firmware_revision_set = 1;
278 	} else
279 		id->aux_firmware_revision_set = 0;
280 
281 	return 0;
282 }
283 
284 /*
285  * Add a low-level interface to the IPMI driver.  Note that if the
286  * interface doesn't know its slave address, it should pass in zero.
287  * The low-level interface should not deliver any messages to the
288  * upper layer until the start_processing() function in the handlers
289  * is called, and the lower layer must get the interface from that
290  * call.
291  */
292 int ipmi_add_smi(struct module            *owner,
293 		 const struct ipmi_smi_handlers *handlers,
294 		 void                     *send_info,
295 		 struct device            *dev,
296 		 unsigned char            slave_addr);
297 
298 #define ipmi_register_smi(handlers, send_info, dev, slave_addr) \
299 	ipmi_add_smi(THIS_MODULE, handlers, send_info, dev, slave_addr)
300 
301 /*
302  * Remove a low-level interface from the IPMI driver.  This will
303  * return an error if the interface is still in use by a user.
304  */
305 void ipmi_unregister_smi(struct ipmi_smi *intf);
306 
307 /*
308  * The lower layer reports received messages through this interface.
309  * The data_size should be zero if this is an asynchronous message.  If
310  * the lower layer gets an error sending a message, it should format
311  * an error response in the message response.
312  */
313 void ipmi_smi_msg_received(struct ipmi_smi     *intf,
314 			   struct ipmi_smi_msg *msg);
315 
316 /* The lower layer received a watchdog pre-timeout on interface. */
317 void ipmi_smi_watchdog_pretimeout(struct ipmi_smi *intf);
318 
319 struct ipmi_smi_msg *ipmi_alloc_smi_msg(void);
ipmi_free_smi_msg(struct ipmi_smi_msg * msg)320 static inline void ipmi_free_smi_msg(struct ipmi_smi_msg *msg)
321 {
322 	msg->done(msg);
323 }
324 
325 #endif /* __LINUX_IPMI_SMI_H */
326