xref: /linux/drivers/misc/sgi-xp/xp.h (revision bcefe12eff5dca6fdfa94ed85e5bee66380d5cd9)
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 #if defined CONFIG_IA64
28 #include <asm/system.h>
29 #include <asm/sn/arch.h>	/* defines is_shub1() and is_shub2() */
30 #define is_shub()	ia64_platform_is("sn2")
31 #endif
32 
33 #ifndef is_shub1
34 #define is_shub1()	0
35 #endif
36 
37 #ifndef is_shub2
38 #define is_shub2()	0
39 #endif
40 
41 #ifndef is_shub
42 #define is_shub()	0
43 #endif
44 
45 #ifdef USE_DBUG_ON
46 #define DBUG_ON(condition)	BUG_ON(condition)
47 #else
48 #define DBUG_ON(condition)
49 #endif
50 
51 /*
52  * Define the maximum number of partitions the system can possibly support.
53  * It is based on the maximum number of hardware partitionable regions. The
54  * term 'region' in this context refers to the minimum number of nodes that
55  * can comprise an access protection grouping. The access protection is in
56  * regards to memory, IPI and IOI.
57  *
58  * The maximum number of hardware partitionable regions is equal to the
59  * maximum number of nodes in the entire system divided by the minimum number
60  * of nodes that comprise an access protection grouping.
61  */
62 #define XP_MAX_NPARTITIONS_SN2	64
63 #define XP_MAX_NPARTITIONS_UV	256
64 
65 /*
66  * XPC establishes channel connections between the local partition and any
67  * other partition that is currently up. Over these channels, kernel-level
68  * `users' can communicate with their counterparts on the other partitions.
69  *
70  * If the need for additional channels arises, one can simply increase
71  * XPC_MAX_NCHANNELS accordingly. If the day should come where that number
72  * exceeds the absolute MAXIMUM number of channels possible (eight), then one
73  * will need to make changes to the XPC code to accommodate for this.
74  *
75  * The absolute maximum number of channels possible is limited to eight for
76  * performance reasons on sn2 hardware. The internal cross partition structures
77  * require sixteen bytes per channel, and eight allows all of this
78  * interface-shared info to fit in one 128-byte cacheline.
79  */
80 #define XPC_MEM_CHANNEL		0	/* memory channel number */
81 #define	XPC_NET_CHANNEL		1	/* network channel number */
82 
83 #define XPC_MAX_NCHANNELS	2	/* max #of channels allowed */
84 
85 #if XPC_MAX_NCHANNELS > 8
86 #error	XPC_MAX_NCHANNELS exceeds absolute MAXIMUM possible.
87 #endif
88 
89 /*
90  * Define macro, XPC_MSG_SIZE(), is provided for the user
91  * that wants to fit as many msg entries as possible in a given memory size
92  * (e.g. a memory page).
93  */
94 #define XPC_MSG_MAX_SIZE	128
95 #define XPC_MSG_HDR_MAX_SIZE	16
96 #define XPC_MSG_PAYLOAD_MAX_SIZE (XPC_MSG_MAX_SIZE - XPC_MSG_HDR_MAX_SIZE)
97 
98 #define XPC_MSG_SIZE(_payload_size) \
99 				ALIGN(XPC_MSG_HDR_MAX_SIZE + (_payload_size), \
100 				      is_uv() ? 64 : 128)
101 
102 
103 /*
104  * Define the return values and values passed to user's callout functions.
105  * (It is important to add new value codes at the end just preceding
106  * xpUnknownReason, which must have the highest numerical value.)
107  */
108 enum xp_retval {
109 	xpSuccess = 0,
110 
111 	xpNotConnected,		/*  1: channel is not connected */
112 	xpConnected,		/*  2: channel connected (opened) */
113 	xpRETIRED1,		/*  3: (formerly xpDisconnected) */
114 
115 	xpMsgReceived,		/*  4: message received */
116 	xpMsgDelivered,		/*  5: message delivered and acknowledged */
117 
118 	xpRETIRED2,		/*  6: (formerly xpTransferFailed) */
119 
120 	xpNoWait,		/*  7: operation would require wait */
121 	xpRetry,		/*  8: retry operation */
122 	xpTimeout,		/*  9: timeout in xpc_allocate_msg_wait() */
123 	xpInterrupted,		/* 10: interrupted wait */
124 
125 	xpUnequalMsgSizes,	/* 11: message size disparity between sides */
126 	xpInvalidAddress,	/* 12: invalid address */
127 
128 	xpNoMemory,		/* 13: no memory available for XPC structures */
129 	xpLackOfResources,	/* 14: insufficient resources for operation */
130 	xpUnregistered,		/* 15: channel is not registered */
131 	xpAlreadyRegistered,	/* 16: channel is already registered */
132 
133 	xpPartitionDown,	/* 17: remote partition is down */
134 	xpNotLoaded,		/* 18: XPC module is not loaded */
135 	xpUnloading,		/* 19: this side is unloading XPC module */
136 
137 	xpBadMagic,		/* 20: XPC MAGIC string not found */
138 
139 	xpReactivating,		/* 21: remote partition was reactivated */
140 
141 	xpUnregistering,	/* 22: this side is unregistering channel */
142 	xpOtherUnregistering,	/* 23: other side is unregistering channel */
143 
144 	xpCloneKThread,		/* 24: cloning kernel thread */
145 	xpCloneKThreadFailed,	/* 25: cloning kernel thread failed */
146 
147 	xpNoHeartbeat,		/* 26: remote partition has no heartbeat */
148 
149 	xpPioReadError,		/* 27: PIO read error */
150 	xpPhysAddrRegFailed,	/* 28: registration of phys addr range failed */
151 
152 	xpRETIRED3,		/* 29: (formerly xpBteDirectoryError) */
153 	xpRETIRED4,		/* 30: (formerly xpBtePoisonError) */
154 	xpRETIRED5,		/* 31: (formerly xpBteWriteError) */
155 	xpRETIRED6,		/* 32: (formerly xpBteAccessError) */
156 	xpRETIRED7,		/* 33: (formerly xpBtePWriteError) */
157 	xpRETIRED8,		/* 34: (formerly xpBtePReadError) */
158 	xpRETIRED9,		/* 35: (formerly xpBteTimeOutError) */
159 	xpRETIRED10,		/* 36: (formerly xpBteXtalkError) */
160 	xpRETIRED11,		/* 37: (formerly xpBteNotAvailable) */
161 	xpRETIRED12,		/* 38: (formerly xpBteUnmappedError) */
162 
163 	xpBadVersion,		/* 39: bad version number */
164 	xpVarsNotSet,		/* 40: the XPC variables are not set up */
165 	xpNoRsvdPageAddr,	/* 41: unable to get rsvd page's phys addr */
166 	xpInvalidPartid,	/* 42: invalid partition ID */
167 	xpLocalPartid,		/* 43: local partition ID */
168 
169 	xpOtherGoingDown,	/* 44: other side going down, reason unknown */
170 	xpSystemGoingDown,	/* 45: system is going down, reason unknown */
171 	xpSystemHalt,		/* 46: system is being halted */
172 	xpSystemReboot,		/* 47: system is being rebooted */
173 	xpSystemPoweroff,	/* 48: system is being powered off */
174 
175 	xpDisconnecting,	/* 49: channel disconnecting (closing) */
176 
177 	xpOpenCloseError,	/* 50: channel open/close protocol error */
178 
179 	xpDisconnected,		/* 51: channel disconnected (closed) */
180 
181 	xpBteCopyError,		/* 52: bte_copy() returned error */
182 	xpSalError,		/* 53: sn SAL error */
183 	xpRsvdPageNotSet,	/* 54: the reserved page is not set up */
184 	xpPayloadTooBig,	/* 55: payload too large for message slot */
185 
186 	xpUnsupported,		/* 56: unsupported functionality or resource */
187 	xpNeedMoreInfo,		/* 57: more info is needed by SAL */
188 
189 	xpGruCopyError,		/* 58: gru_copy_gru() returned error */
190 	xpGruSendMqError,	/* 59: gru send message queue related error */
191 
192 	xpBadChannelNumber,	/* 60: invalid channel number */
193 	xpBadMsgType,		/* 61: invalid message type */
194 	xpBiosError,		/* 62: BIOS error */
195 
196 	xpUnknownReason		/* 63: unknown reason - must be last in enum */
197 };
198 
199 /*
200  * Define the callout function type used by XPC to update the user on
201  * connection activity and state changes via the user function registered
202  * by xpc_connect().
203  *
204  * Arguments:
205  *
206  *	reason - reason code.
207  *	partid - partition ID associated with condition.
208  *	ch_number - channel # associated with condition.
209  *	data - pointer to optional data.
210  *	key - pointer to optional user-defined value provided as the "key"
211  *	      argument to xpc_connect().
212  *
213  * A reason code of xpConnected indicates that a connection has been
214  * established to the specified partition on the specified channel. The data
215  * argument indicates the max number of entries allowed in the message queue.
216  *
217  * A reason code of xpMsgReceived indicates that a XPC message arrived from
218  * the specified partition on the specified channel. The data argument
219  * specifies the address of the message's payload. The user must call
220  * xpc_received() when finished with the payload.
221  *
222  * All other reason codes indicate failure. The data argmument is NULL.
223  * When a failure reason code is received, one can assume that the channel
224  * is not connected.
225  */
226 typedef void (*xpc_channel_func) (enum xp_retval reason, short partid,
227 				  int ch_number, void *data, void *key);
228 
229 /*
230  * Define the callout function type used by XPC to notify the user of
231  * messages received and delivered via the user function registered by
232  * xpc_send_notify().
233  *
234  * Arguments:
235  *
236  *	reason - reason code.
237  *	partid - partition ID associated with condition.
238  *	ch_number - channel # associated with condition.
239  *	key - pointer to optional user-defined value provided as the "key"
240  *	      argument to xpc_send_notify().
241  *
242  * A reason code of xpMsgDelivered indicates that the message was delivered
243  * to the intended recipient and that they have acknowledged its receipt by
244  * calling xpc_received().
245  *
246  * All other reason codes indicate failure.
247  *
248  * NOTE: The user defined function must be callable by an interrupt handler
249  *       and thus cannot block.
250  */
251 typedef void (*xpc_notify_func) (enum xp_retval reason, short partid,
252 				 int ch_number, void *key);
253 
254 /*
255  * The following is a registration entry. There is a global array of these,
256  * one per channel. It is used to record the connection registration made
257  * by the users of XPC. As long as a registration entry exists, for any
258  * partition that comes up, XPC will attempt to establish a connection on
259  * that channel. Notification that a connection has been made will occur via
260  * the xpc_channel_func function.
261  *
262  * The 'func' field points to the function to call when aynchronous
263  * notification is required for such events as: a connection established/lost,
264  * or an incoming message received, or an error condition encountered. A
265  * non-NULL 'func' field indicates that there is an active registration for
266  * the channel.
267  */
268 struct xpc_registration {
269 	struct mutex mutex;
270 	xpc_channel_func func;	/* function to call */
271 	void *key;		/* pointer to user's key */
272 	u16 nentries;		/* #of msg entries in local msg queue */
273 	u16 entry_size;		/* message queue's message entry size */
274 	u32 assigned_limit;	/* limit on #of assigned kthreads */
275 	u32 idle_limit;		/* limit on #of idle kthreads */
276 } ____cacheline_aligned;
277 
278 #define XPC_CHANNEL_REGISTERED(_c)	(xpc_registrations[_c].func != NULL)
279 
280 /* the following are valid xpc_send() or xpc_send_notify() flags */
281 #define XPC_WAIT	0	/* wait flag */
282 #define XPC_NOWAIT	1	/* no wait flag */
283 
284 struct xpc_interface {
285 	void (*connect) (int);
286 	void (*disconnect) (int);
287 	enum xp_retval (*send) (short, int, u32, void *, u16);
288 	enum xp_retval (*send_notify) (short, int, u32, void *, u16,
289 					xpc_notify_func, void *);
290 	void (*received) (short, int, void *);
291 	enum xp_retval (*partid_to_nasids) (short, void *);
292 };
293 
294 extern struct xpc_interface xpc_interface;
295 
296 extern void xpc_set_interface(void (*)(int),
297 			      void (*)(int),
298 			      enum xp_retval (*)(short, int, u32, void *, u16),
299 			      enum xp_retval (*)(short, int, u32, void *, u16,
300 						 xpc_notify_func, void *),
301 			      void (*)(short, int, void *),
302 			      enum xp_retval (*)(short, void *));
303 extern void xpc_clear_interface(void);
304 
305 extern enum xp_retval xpc_connect(int, xpc_channel_func, void *, u16,
306 				   u16, u32, u32);
307 extern void xpc_disconnect(int);
308 
309 static inline enum xp_retval
310 xpc_send(short partid, int ch_number, u32 flags, void *payload,
311 	 u16 payload_size)
312 {
313 	return xpc_interface.send(partid, ch_number, flags, payload,
314 				  payload_size);
315 }
316 
317 static inline enum xp_retval
318 xpc_send_notify(short partid, int ch_number, u32 flags, void *payload,
319 		u16 payload_size, xpc_notify_func func, void *key)
320 {
321 	return xpc_interface.send_notify(partid, ch_number, flags, payload,
322 					 payload_size, func, key);
323 }
324 
325 static inline void
326 xpc_received(short partid, int ch_number, void *payload)
327 {
328 	return xpc_interface.received(partid, ch_number, payload);
329 }
330 
331 static inline enum xp_retval
332 xpc_partid_to_nasids(short partid, void *nasids)
333 {
334 	return xpc_interface.partid_to_nasids(partid, nasids);
335 }
336 
337 extern short xp_max_npartitions;
338 extern short xp_partition_id;
339 extern u8 xp_region_size;
340 
341 extern unsigned long (*xp_pa) (void *);
342 extern enum xp_retval (*xp_remote_memcpy) (unsigned long, const unsigned long,
343 		       size_t);
344 extern int (*xp_cpu_to_nasid) (int);
345 extern enum xp_retval (*xp_expand_memprotect) (unsigned long, unsigned long);
346 extern enum xp_retval (*xp_restrict_memprotect) (unsigned long, unsigned long);
347 
348 extern u64 xp_nofault_PIOR_target;
349 extern int xp_nofault_PIOR(void *);
350 extern int xp_error_PIOR(void);
351 
352 extern struct device *xp;
353 extern enum xp_retval xp_init_sn2(void);
354 extern enum xp_retval xp_init_uv(void);
355 extern void xp_exit_sn2(void);
356 extern void xp_exit_uv(void);
357 
358 #endif /* _DRIVERS_MISC_SGIXP_XP_H */
359