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 typedef struct ipmi_smi *ipmi_smi_t;
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  * Messages to/from the lower layer.  The smi interface will take one
43  * of these to send. After the send has occurred and a response has
44  * been received, it will report this same data structure back up to
45  * the upper layer.  If an error occurs, it should fill in the
46  * response with an error code in the completion code location. When
47  * asynchronous data is received, one of these is allocated, the
48  * data_size is set to zero and the response holds the data from the
49  * get message or get event command that the interface initiated.
50  * Note that it is the interfaces responsibility to detect
51  * asynchronous data and messages and request them from the
52  * interface.
53  */
54 struct ipmi_smi_msg {
55 	struct list_head link;
56 
57 	long    msgid;
58 	void    *user_data;
59 
60 	int           data_size;
61 	unsigned char data[IPMI_MAX_MSG_LENGTH];
62 
63 	int           rsp_size;
64 	unsigned char rsp[IPMI_MAX_MSG_LENGTH];
65 
66 	/*
67 	 * Will be called when the system is done with the message
68 	 * (presumably to free it).
69 	 */
70 	void (*done)(struct ipmi_smi_msg *msg);
71 };
72 
73 struct ipmi_smi_handlers {
74 	struct module *owner;
75 
76 	/*
77 	 * The low-level interface cannot start sending messages to
78 	 * the upper layer until this function is called.  This may
79 	 * not be NULL, the lower layer must take the interface from
80 	 * this call.
81 	 */
82 	int (*start_processing)(void            *send_info,
83 				struct ipmi_smi *new_intf);
84 
85 	/*
86 	 * When called, the low-level interface should disable all
87 	 * processing, it should be complete shut down when it returns.
88 	 */
89 	void (*shutdown)(void *send_info);
90 
91 	/*
92 	 * Get the detailed private info of the low level interface and store
93 	 * it into the structure of ipmi_smi_data. For example: the
94 	 * ACPI device handle will be returned for the pnp_acpi IPMI device.
95 	 */
96 	int (*get_smi_info)(void *send_info, struct ipmi_smi_info *data);
97 
98 	/*
99 	 * Called to enqueue an SMI message to be sent.  This
100 	 * operation is not allowed to fail.  If an error occurs, it
101 	 * should report back the error in a received message.  It may
102 	 * do this in the current call context, since no write locks
103 	 * are held when this is run.  Message are delivered one at
104 	 * a time by the message handler, a new message will not be
105 	 * delivered until the previous message is returned.
106 	 */
107 	void (*sender)(void                *send_info,
108 		       struct ipmi_smi_msg *msg);
109 
110 	/*
111 	 * Called by the upper layer to request that we try to get
112 	 * events from the BMC we are attached to.
113 	 */
114 	void (*request_events)(void *send_info);
115 
116 	/*
117 	 * Called by the upper layer when some user requires that the
118 	 * interface watch for received messages and watchdog
119 	 * pretimeouts (basically do a "Get Flags", or not.  Used by
120 	 * the SMI to know if it should watch for these.  This may be
121 	 * NULL if the SMI does not implement it.  watch_mask is from
122 	 * IPMI_WATCH_MASK_xxx above.  The interface should run slower
123 	 * timeouts for just watchdog checking or faster timeouts when
124 	 * waiting for the message queue.
125 	 */
126 	void (*set_need_watch)(void *send_info, unsigned int watch_mask);
127 
128 	/*
129 	 * Called when flushing all pending messages.
130 	 */
131 	void (*flush_messages)(void *send_info);
132 
133 	/*
134 	 * Called when the interface should go into "run to
135 	 * completion" mode.  If this call sets the value to true, the
136 	 * interface should make sure that all messages are flushed
137 	 * out and that none are pending, and any new requests are run
138 	 * to completion immediately.
139 	 */
140 	void (*set_run_to_completion)(void *send_info, bool run_to_completion);
141 
142 	/*
143 	 * Called to poll for work to do.  This is so upper layers can
144 	 * poll for operations during things like crash dumps.
145 	 */
146 	void (*poll)(void *send_info);
147 
148 	/*
149 	 * Enable/disable firmware maintenance mode.  Note that this
150 	 * is *not* the modes defined, this is simply an on/off
151 	 * setting.  The message handler does the mode handling.  Note
152 	 * that this is called from interrupt context, so it cannot
153 	 * block.
154 	 */
155 	void (*set_maintenance_mode)(void *send_info, bool enable);
156 };
157 
158 struct ipmi_device_id {
159 	unsigned char device_id;
160 	unsigned char device_revision;
161 	unsigned char firmware_revision_1;
162 	unsigned char firmware_revision_2;
163 	unsigned char ipmi_version;
164 	unsigned char additional_device_support;
165 	unsigned int  manufacturer_id;
166 	unsigned int  product_id;
167 	unsigned char aux_firmware_revision[4];
168 	unsigned int  aux_firmware_revision_set : 1;
169 };
170 
171 #define ipmi_version_major(v) ((v)->ipmi_version & 0xf)
172 #define ipmi_version_minor(v) ((v)->ipmi_version >> 4)
173 
174 /*
175  * Take a pointer to an IPMI response and extract device id information from
176  * it. @netfn is in the IPMI_NETFN_ format, so may need to be shifted from
177  * a SI response.
178  */
ipmi_demangle_device_id(uint8_t netfn,uint8_t cmd,const unsigned char * data,unsigned int data_len,struct ipmi_device_id * id)179 static inline int ipmi_demangle_device_id(uint8_t netfn, uint8_t cmd,
180 					  const unsigned char *data,
181 					  unsigned int data_len,
182 					  struct ipmi_device_id *id)
183 {
184 	if (data_len < 7)
185 		return -EINVAL;
186 	if (netfn != IPMI_NETFN_APP_RESPONSE || cmd != IPMI_GET_DEVICE_ID_CMD)
187 		/* Strange, didn't get the response we expected. */
188 		return -EINVAL;
189 	if (data[0] != 0)
190 		/* That's odd, it shouldn't be able to fail. */
191 		return -EINVAL;
192 
193 	data++;
194 	data_len--;
195 
196 	id->device_id = data[0];
197 	id->device_revision = data[1];
198 	id->firmware_revision_1 = data[2];
199 	id->firmware_revision_2 = data[3];
200 	id->ipmi_version = data[4];
201 	id->additional_device_support = data[5];
202 	if (data_len >= 11) {
203 		id->manufacturer_id = (data[6] | (data[7] << 8) |
204 				       (data[8] << 16));
205 		id->product_id = data[9] | (data[10] << 8);
206 	} else {
207 		id->manufacturer_id = 0;
208 		id->product_id = 0;
209 	}
210 	if (data_len >= 15) {
211 		memcpy(id->aux_firmware_revision, data+11, 4);
212 		id->aux_firmware_revision_set = 1;
213 	} else
214 		id->aux_firmware_revision_set = 0;
215 
216 	return 0;
217 }
218 
219 /*
220  * Add a low-level interface to the IPMI driver.  Note that if the
221  * interface doesn't know its slave address, it should pass in zero.
222  * The low-level interface should not deliver any messages to the
223  * upper layer until the start_processing() function in the handlers
224  * is called, and the lower layer must get the interface from that
225  * call.
226  */
227 int ipmi_add_smi(struct module            *owner,
228 		 const struct ipmi_smi_handlers *handlers,
229 		 void                     *send_info,
230 		 struct device            *dev,
231 		 unsigned char            slave_addr);
232 
233 #define ipmi_register_smi(handlers, send_info, dev, slave_addr) \
234 	ipmi_add_smi(THIS_MODULE, handlers, send_info, dev, slave_addr)
235 
236 /*
237  * Remove a low-level interface from the IPMI driver.  This will
238  * return an error if the interface is still in use by a user.
239  */
240 void ipmi_unregister_smi(struct ipmi_smi *intf);
241 
242 /*
243  * The lower layer reports received messages through this interface.
244  * The data_size should be zero if this is an asynchronous message.  If
245  * the lower layer gets an error sending a message, it should format
246  * an error response in the message response.
247  */
248 void ipmi_smi_msg_received(struct ipmi_smi     *intf,
249 			   struct ipmi_smi_msg *msg);
250 
251 /* The lower layer received a watchdog pre-timeout on interface. */
252 void ipmi_smi_watchdog_pretimeout(struct ipmi_smi *intf);
253 
254 struct ipmi_smi_msg *ipmi_alloc_smi_msg(void);
ipmi_free_smi_msg(struct ipmi_smi_msg * msg)255 static inline void ipmi_free_smi_msg(struct ipmi_smi_msg *msg)
256 {
257 	msg->done(msg);
258 }
259 
260 #endif /* __LINUX_IPMI_SMI_H */
261