xref: /openbmc/linux/drivers/misc/sgi-xp/xp.h (revision a44e4f3a)
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Copyright (C) 2004-2008 Silicon Graphics, Inc. All rights reserved.
7  */
8 
9 /*
10  * External Cross Partition (XP) structures and defines.
11  */
12 
13 #ifndef _DRIVERS_MISC_SGIXP_XP_H
14 #define _DRIVERS_MISC_SGIXP_XP_H
15 
16 #include <linux/mutex.h>
17 
18 #if defined CONFIG_X86_UV || defined CONFIG_IA64_SGI_UV
19 #include <asm/uv/uv.h>
20 #define is_uv()		is_uv_system()
21 #endif
22 
23 #ifndef is_uv
24 #define is_uv()		0
25 #endif
26 
27 #ifdef USE_DBUG_ON
28 #define DBUG_ON(condition)	BUG_ON(condition)
29 #else
30 #define DBUG_ON(condition)
31 #endif
32 
33 /*
34  * Define the maximum number of partitions the system can possibly support.
35  * It is based on the maximum number of hardware partitionable regions. The
36  * term 'region' in this context refers to the minimum number of nodes that
37  * can comprise an access protection grouping. The access protection is in
38  * regards to memory, IPI and IOI.
39  *
40  * The maximum number of hardware partitionable regions is equal to the
41  * maximum number of nodes in the entire system divided by the minimum number
42  * of nodes that comprise an access protection grouping.
43  */
44 #define XP_MAX_NPARTITIONS_SN2	64
45 #define XP_MAX_NPARTITIONS_UV	256
46 
47 /*
48  * XPC establishes channel connections between the local partition and any
49  * other partition that is currently up. Over these channels, kernel-level
50  * `users' can communicate with their counterparts on the other partitions.
51  *
52  * If the need for additional channels arises, one can simply increase
53  * XPC_MAX_NCHANNELS accordingly. If the day should come where that number
54  * exceeds the absolute MAXIMUM number of channels possible (eight), then one
55  * will need to make changes to the XPC code to accommodate for this.
56  *
57  * The absolute maximum number of channels possible is limited to eight for
58  * performance reasons on sn2 hardware. The internal cross partition structures
59  * require sixteen bytes per channel, and eight allows all of this
60  * interface-shared info to fit in one 128-byte cacheline.
61  */
62 #define XPC_MEM_CHANNEL		0	/* memory channel number */
63 #define	XPC_NET_CHANNEL		1	/* network channel number */
64 
65 #define XPC_MAX_NCHANNELS	2	/* max #of channels allowed */
66 
67 #if XPC_MAX_NCHANNELS > 8
68 #error	XPC_MAX_NCHANNELS exceeds absolute MAXIMUM possible.
69 #endif
70 
71 /*
72  * Define macro, XPC_MSG_SIZE(), is provided for the user
73  * that wants to fit as many msg entries as possible in a given memory size
74  * (e.g. a memory page).
75  */
76 #define XPC_MSG_MAX_SIZE	128
77 #define XPC_MSG_HDR_MAX_SIZE	16
78 #define XPC_MSG_PAYLOAD_MAX_SIZE (XPC_MSG_MAX_SIZE - XPC_MSG_HDR_MAX_SIZE)
79 
80 #define XPC_MSG_SIZE(_payload_size) \
81 				ALIGN(XPC_MSG_HDR_MAX_SIZE + (_payload_size), \
82 				      is_uv() ? 64 : 128)
83 
84 
85 /*
86  * Define the return values and values passed to user's callout functions.
87  * (It is important to add new value codes at the end just preceding
88  * xpUnknownReason, which must have the highest numerical value.)
89  */
90 enum xp_retval {
91 	xpSuccess = 0,
92 
93 	xpNotConnected,		/*  1: channel is not connected */
94 	xpConnected,		/*  2: channel connected (opened) */
95 	xpRETIRED1,		/*  3: (formerly xpDisconnected) */
96 
97 	xpMsgReceived,		/*  4: message received */
98 	xpMsgDelivered,		/*  5: message delivered and acknowledged */
99 
100 	xpRETIRED2,		/*  6: (formerly xpTransferFailed) */
101 
102 	xpNoWait,		/*  7: operation would require wait */
103 	xpRetry,		/*  8: retry operation */
104 	xpTimeout,		/*  9: timeout in xpc_allocate_msg_wait() */
105 	xpInterrupted,		/* 10: interrupted wait */
106 
107 	xpUnequalMsgSizes,	/* 11: message size disparity between sides */
108 	xpInvalidAddress,	/* 12: invalid address */
109 
110 	xpNoMemory,		/* 13: no memory available for XPC structures */
111 	xpLackOfResources,	/* 14: insufficient resources for operation */
112 	xpUnregistered,		/* 15: channel is not registered */
113 	xpAlreadyRegistered,	/* 16: channel is already registered */
114 
115 	xpPartitionDown,	/* 17: remote partition is down */
116 	xpNotLoaded,		/* 18: XPC module is not loaded */
117 	xpUnloading,		/* 19: this side is unloading XPC module */
118 
119 	xpBadMagic,		/* 20: XPC MAGIC string not found */
120 
121 	xpReactivating,		/* 21: remote partition was reactivated */
122 
123 	xpUnregistering,	/* 22: this side is unregistering channel */
124 	xpOtherUnregistering,	/* 23: other side is unregistering channel */
125 
126 	xpCloneKThread,		/* 24: cloning kernel thread */
127 	xpCloneKThreadFailed,	/* 25: cloning kernel thread failed */
128 
129 	xpNoHeartbeat,		/* 26: remote partition has no heartbeat */
130 
131 	xpPioReadError,		/* 27: PIO read error */
132 	xpPhysAddrRegFailed,	/* 28: registration of phys addr range failed */
133 
134 	xpRETIRED3,		/* 29: (formerly xpBteDirectoryError) */
135 	xpRETIRED4,		/* 30: (formerly xpBtePoisonError) */
136 	xpRETIRED5,		/* 31: (formerly xpBteWriteError) */
137 	xpRETIRED6,		/* 32: (formerly xpBteAccessError) */
138 	xpRETIRED7,		/* 33: (formerly xpBtePWriteError) */
139 	xpRETIRED8,		/* 34: (formerly xpBtePReadError) */
140 	xpRETIRED9,		/* 35: (formerly xpBteTimeOutError) */
141 	xpRETIRED10,		/* 36: (formerly xpBteXtalkError) */
142 	xpRETIRED11,		/* 37: (formerly xpBteNotAvailable) */
143 	xpRETIRED12,		/* 38: (formerly xpBteUnmappedError) */
144 
145 	xpBadVersion,		/* 39: bad version number */
146 	xpVarsNotSet,		/* 40: the XPC variables are not set up */
147 	xpNoRsvdPageAddr,	/* 41: unable to get rsvd page's phys addr */
148 	xpInvalidPartid,	/* 42: invalid partition ID */
149 	xpLocalPartid,		/* 43: local partition ID */
150 
151 	xpOtherGoingDown,	/* 44: other side going down, reason unknown */
152 	xpSystemGoingDown,	/* 45: system is going down, reason unknown */
153 	xpSystemHalt,		/* 46: system is being halted */
154 	xpSystemReboot,		/* 47: system is being rebooted */
155 	xpSystemPoweroff,	/* 48: system is being powered off */
156 
157 	xpDisconnecting,	/* 49: channel disconnecting (closing) */
158 
159 	xpOpenCloseError,	/* 50: channel open/close protocol error */
160 
161 	xpDisconnected,		/* 51: channel disconnected (closed) */
162 
163 	xpBteCopyError,		/* 52: bte_copy() returned error */
164 	xpSalError,		/* 53: sn SAL error */
165 	xpRsvdPageNotSet,	/* 54: the reserved page is not set up */
166 	xpPayloadTooBig,	/* 55: payload too large for message slot */
167 
168 	xpUnsupported,		/* 56: unsupported functionality or resource */
169 	xpNeedMoreInfo,		/* 57: more info is needed by SAL */
170 
171 	xpGruCopyError,		/* 58: gru_copy_gru() returned error */
172 	xpGruSendMqError,	/* 59: gru send message queue related error */
173 
174 	xpBadChannelNumber,	/* 60: invalid channel number */
175 	xpBadMsgType,		/* 61: invalid message type */
176 	xpBiosError,		/* 62: BIOS error */
177 
178 	xpUnknownReason		/* 63: unknown reason - must be last in enum */
179 };
180 
181 /*
182  * Define the callout function type used by XPC to update the user on
183  * connection activity and state changes via the user function registered
184  * by xpc_connect().
185  *
186  * Arguments:
187  *
188  *	reason - reason code.
189  *	partid - partition ID associated with condition.
190  *	ch_number - channel # associated with condition.
191  *	data - pointer to optional data.
192  *	key - pointer to optional user-defined value provided as the "key"
193  *	      argument to xpc_connect().
194  *
195  * A reason code of xpConnected indicates that a connection has been
196  * established to the specified partition on the specified channel. The data
197  * argument indicates the max number of entries allowed in the message queue.
198  *
199  * A reason code of xpMsgReceived indicates that a XPC message arrived from
200  * the specified partition on the specified channel. The data argument
201  * specifies the address of the message's payload. The user must call
202  * xpc_received() when finished with the payload.
203  *
204  * All other reason codes indicate failure. The data argmument is NULL.
205  * When a failure reason code is received, one can assume that the channel
206  * is not connected.
207  */
208 typedef void (*xpc_channel_func) (enum xp_retval reason, short partid,
209 				  int ch_number, void *data, void *key);
210 
211 /*
212  * Define the callout function type used by XPC to notify the user of
213  * messages received and delivered via the user function registered by
214  * xpc_send_notify().
215  *
216  * Arguments:
217  *
218  *	reason - reason code.
219  *	partid - partition ID associated with condition.
220  *	ch_number - channel # associated with condition.
221  *	key - pointer to optional user-defined value provided as the "key"
222  *	      argument to xpc_send_notify().
223  *
224  * A reason code of xpMsgDelivered indicates that the message was delivered
225  * to the intended recipient and that they have acknowledged its receipt by
226  * calling xpc_received().
227  *
228  * All other reason codes indicate failure.
229  *
230  * NOTE: The user defined function must be callable by an interrupt handler
231  *       and thus cannot block.
232  */
233 typedef void (*xpc_notify_func) (enum xp_retval reason, short partid,
234 				 int ch_number, void *key);
235 
236 /*
237  * The following is a registration entry. There is a global array of these,
238  * one per channel. It is used to record the connection registration made
239  * by the users of XPC. As long as a registration entry exists, for any
240  * partition that comes up, XPC will attempt to establish a connection on
241  * that channel. Notification that a connection has been made will occur via
242  * the xpc_channel_func function.
243  *
244  * The 'func' field points to the function to call when aynchronous
245  * notification is required for such events as: a connection established/lost,
246  * or an incoming message received, or an error condition encountered. A
247  * non-NULL 'func' field indicates that there is an active registration for
248  * the channel.
249  */
250 struct xpc_registration {
251 	struct mutex mutex;
252 	xpc_channel_func func;	/* function to call */
253 	void *key;		/* pointer to user's key */
254 	u16 nentries;		/* #of msg entries in local msg queue */
255 	u16 entry_size;		/* message queue's message entry size */
256 	u32 assigned_limit;	/* limit on #of assigned kthreads */
257 	u32 idle_limit;		/* limit on #of idle kthreads */
258 } ____cacheline_aligned;
259 
260 #define XPC_CHANNEL_REGISTERED(_c)	(xpc_registrations[_c].func != NULL)
261 
262 /* the following are valid xpc_send() or xpc_send_notify() flags */
263 #define XPC_WAIT	0	/* wait flag */
264 #define XPC_NOWAIT	1	/* no wait flag */
265 
266 struct xpc_interface {
267 	void (*connect) (int);
268 	void (*disconnect) (int);
269 	enum xp_retval (*send) (short, int, u32, void *, u16);
270 	enum xp_retval (*send_notify) (short, int, u32, void *, u16,
271 					xpc_notify_func, void *);
272 	void (*received) (short, int, void *);
273 	enum xp_retval (*partid_to_nasids) (short, void *);
274 };
275 
276 extern struct xpc_interface xpc_interface;
277 
278 extern void xpc_set_interface(void (*)(int),
279 			      void (*)(int),
280 			      enum xp_retval (*)(short, int, u32, void *, u16),
281 			      enum xp_retval (*)(short, int, u32, void *, u16,
282 						 xpc_notify_func, void *),
283 			      void (*)(short, int, void *),
284 			      enum xp_retval (*)(short, void *));
285 extern void xpc_clear_interface(void);
286 
287 extern enum xp_retval xpc_connect(int, xpc_channel_func, void *, u16,
288 				   u16, u32, u32);
289 extern void xpc_disconnect(int);
290 
291 static inline enum xp_retval
292 xpc_send(short partid, int ch_number, u32 flags, void *payload,
293 	 u16 payload_size)
294 {
295 	if (!xpc_interface.send)
296 		return xpNotLoaded;
297 
298 	return xpc_interface.send(partid, ch_number, flags, payload,
299 				  payload_size);
300 }
301 
302 static inline enum xp_retval
303 xpc_send_notify(short partid, int ch_number, u32 flags, void *payload,
304 		u16 payload_size, xpc_notify_func func, void *key)
305 {
306 	if (!xpc_interface.send_notify)
307 		return xpNotLoaded;
308 
309 	return xpc_interface.send_notify(partid, ch_number, flags, payload,
310 					 payload_size, func, key);
311 }
312 
313 static inline void
314 xpc_received(short partid, int ch_number, void *payload)
315 {
316 	if (xpc_interface.received)
317 		xpc_interface.received(partid, ch_number, payload);
318 }
319 
320 static inline enum xp_retval
321 xpc_partid_to_nasids(short partid, void *nasids)
322 {
323 	if (!xpc_interface.partid_to_nasids)
324 		return xpNotLoaded;
325 
326 	return xpc_interface.partid_to_nasids(partid, nasids);
327 }
328 
329 extern short xp_max_npartitions;
330 extern short xp_partition_id;
331 extern u8 xp_region_size;
332 
333 extern unsigned long (*xp_pa) (void *);
334 extern unsigned long (*xp_socket_pa) (unsigned long);
335 extern enum xp_retval (*xp_remote_memcpy) (unsigned long, const unsigned long,
336 		       size_t);
337 extern int (*xp_cpu_to_nasid) (int);
338 extern enum xp_retval (*xp_expand_memprotect) (unsigned long, unsigned long);
339 extern enum xp_retval (*xp_restrict_memprotect) (unsigned long, unsigned long);
340 
341 extern u64 xp_nofault_PIOR_target;
342 extern int xp_nofault_PIOR(void *);
343 extern int xp_error_PIOR(void);
344 
345 extern struct device *xp;
346 extern enum xp_retval xp_init_uv(void);
347 extern void xp_exit_uv(void);
348 
349 #endif /* _DRIVERS_MISC_SGIXP_XP_H */
350