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
23struct 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. */
31struct 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
89enum 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 */
107struct 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
134struct 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
223struct 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 */
244static 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 */
292int 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 */
305void 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 */
313void 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. */
317void ipmi_smi_watchdog_pretimeout(struct ipmi_smi *intf);
318
319struct ipmi_smi_msg *ipmi_alloc_smi_msg(void);
320static 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