xref: /openbmc/linux/drivers/char/ipmi/ipmi_si_sm.h (revision 4f6cce39)
1 /*
2  * ipmi_si_sm.h
3  *
4  * State machine interface for low-level IPMI system management
5  * interface state machines.  This code is the interface between
6  * the ipmi_smi code (that handles the policy of a KCS, SMIC, or
7  * BT interface) and the actual low-level state machine.
8  *
9  * Author: MontaVista Software, Inc.
10  *         Corey Minyard <minyard@mvista.com>
11  *         source@mvista.com
12  *
13  * Copyright 2002 MontaVista Software Inc.
14  *
15  *  This program is free software; you can redistribute it and/or modify it
16  *  under the terms of the GNU General Public License as published by the
17  *  Free Software Foundation; either version 2 of the License, or (at your
18  *  option) any later version.
19  *
20  *
21  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
22  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
23  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24  *  IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25  *  INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
26  *  BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
27  *  OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
28  *  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
29  *  TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
30  *  USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31  *
32  *  You should have received a copy of the GNU General Public License along
33  *  with this program; if not, write to the Free Software Foundation, Inc.,
34  *  675 Mass Ave, Cambridge, MA 02139, USA.
35  */
36 
37 /*
38  * This is defined by the state machines themselves, it is an opaque
39  * data type for them to use.
40  */
41 struct si_sm_data;
42 
43 /*
44  * The structure for doing I/O in the state machine.  The state
45  * machine doesn't have the actual I/O routines, they are done through
46  * this interface.
47  */
48 struct si_sm_io {
49 	unsigned char (*inputb)(const struct si_sm_io *io, unsigned int offset);
50 	void (*outputb)(const struct si_sm_io *io,
51 			unsigned int  offset,
52 			unsigned char b);
53 
54 	/*
55 	 * Generic info used by the actual handling routines, the
56 	 * state machine shouldn't touch these.
57 	 */
58 	void __iomem *addr;
59 	int  regspacing;
60 	int  regsize;
61 	int  regshift;
62 	int addr_type;
63 	long addr_data;
64 };
65 
66 /* Results of SMI events. */
67 enum si_sm_result {
68 	SI_SM_CALL_WITHOUT_DELAY, /* Call the driver again immediately */
69 	SI_SM_CALL_WITH_DELAY,	/* Delay some before calling again. */
70 	SI_SM_CALL_WITH_TICK_DELAY,/* Delay >=1 tick before calling again. */
71 	SI_SM_TRANSACTION_COMPLETE, /* A transaction is finished. */
72 	SI_SM_IDLE,		/* The SM is in idle state. */
73 	SI_SM_HOSED,		/* The hardware violated the state machine. */
74 
75 	/*
76 	 * The hardware is asserting attn and the state machine is
77 	 * idle.
78 	 */
79 	SI_SM_ATTN
80 };
81 
82 /* Handlers for the SMI state machine. */
83 struct si_sm_handlers {
84 	/*
85 	 * Put the version number of the state machine here so the
86 	 * upper layer can print it.
87 	 */
88 	char *version;
89 
90 	/*
91 	 * Initialize the data and return the amount of I/O space to
92 	 * reserve for the space.
93 	 */
94 	unsigned int (*init_data)(struct si_sm_data *smi,
95 				  struct si_sm_io   *io);
96 
97 	/*
98 	 * Start a new transaction in the state machine.  This will
99 	 * return -2 if the state machine is not idle, -1 if the size
100 	 * is invalid (to large or too small), or 0 if the transaction
101 	 * is successfully completed.
102 	 */
103 	int (*start_transaction)(struct si_sm_data *smi,
104 				 unsigned char *data, unsigned int size);
105 
106 	/*
107 	 * Return the results after the transaction.  This will return
108 	 * -1 if the buffer is too small, zero if no transaction is
109 	 * present, or the actual length of the result data.
110 	 */
111 	int (*get_result)(struct si_sm_data *smi,
112 			  unsigned char *data, unsigned int length);
113 
114 	/*
115 	 * Call this periodically (for a polled interface) or upon
116 	 * receiving an interrupt (for a interrupt-driven interface).
117 	 * If interrupt driven, you should probably poll this
118 	 * periodically when not in idle state.  This should be called
119 	 * with the time that passed since the last call, if it is
120 	 * significant.  Time is in microseconds.
121 	 */
122 	enum si_sm_result (*event)(struct si_sm_data *smi, long time);
123 
124 	/*
125 	 * Attempt to detect an SMI.  Returns 0 on success or nonzero
126 	 * on failure.
127 	 */
128 	int (*detect)(struct si_sm_data *smi);
129 
130 	/* The interface is shutting down, so clean it up. */
131 	void (*cleanup)(struct si_sm_data *smi);
132 
133 	/* Return the size of the SMI structure in bytes. */
134 	int (*size)(void);
135 };
136 
137 /* Current state machines that we can use. */
138 extern const struct si_sm_handlers kcs_smi_handlers;
139 extern const struct si_sm_handlers smic_smi_handlers;
140 extern const struct si_sm_handlers bt_smi_handlers;
141 
142