xref: /linux/drivers/misc/sgi-xp/xp.h (revision b233b28eac0cc37d07c2d007ea08c86c778c5af4)
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 #ifdef CONFIG_IA64
19 #include <asm/system.h>
20 #include <asm/sn/arch.h>	/* defines is_shub1() and is_shub2() */
21 #define is_shub()	ia64_platform_is("sn2")
22 #ifdef CONFIG_IA64_SGI_UV
23 #define is_uv()		ia64_platform_is("uv")
24 #else
25 #define is_uv()		0
26 #endif
27 #endif
28 #ifdef CONFIG_X86_64
29 #include <asm/genapic.h>
30 #define is_uv()		is_uv_system()
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 #ifndef is_uv
46 #define is_uv()		0
47 #endif
48 
49 #ifdef USE_DBUG_ON
50 #define DBUG_ON(condition)	BUG_ON(condition)
51 #else
52 #define DBUG_ON(condition)
53 #endif
54 
55 /*
56  * Define the maximum number of partitions the system can possibly support.
57  * It is based on the maximum number of hardware partitionable regions. The
58  * term 'region' in this context refers to the minimum number of nodes that
59  * can comprise an access protection grouping. The access protection is in
60  * regards to memory, IPI and IOI.
61  *
62  * The maximum number of hardware partitionable regions is equal to the
63  * maximum number of nodes in the entire system divided by the minimum number
64  * of nodes that comprise an access protection grouping.
65  */
66 #define XP_MAX_NPARTITIONS_SN2	64
67 #define XP_MAX_NPARTITIONS_UV	256
68 
69 /*
70  * XPC establishes channel connections between the local partition and any
71  * other partition that is currently up. Over these channels, kernel-level
72  * `users' can communicate with their counterparts on the other partitions.
73  *
74  * If the need for additional channels arises, one can simply increase
75  * XPC_MAX_NCHANNELS accordingly. If the day should come where that number
76  * exceeds the absolute MAXIMUM number of channels possible (eight), then one
77  * will need to make changes to the XPC code to accommodate for this.
78  *
79  * The absolute maximum number of channels possible is limited to eight for
80  * performance reasons on sn2 hardware. The internal cross partition structures
81  * require sixteen bytes per channel, and eight allows all of this
82  * interface-shared info to fit in one 128-byte cacheline.
83  */
84 #define XPC_MEM_CHANNEL		0	/* memory channel number */
85 #define	XPC_NET_CHANNEL		1	/* network channel number */
86 
87 #define XPC_MAX_NCHANNELS	2	/* max #of channels allowed */
88 
89 #if XPC_MAX_NCHANNELS > 8
90 #error	XPC_MAX_NCHANNELS exceeds absolute MAXIMUM possible.
91 #endif
92 
93 /*
94  * Define macro, XPC_MSG_SIZE(), is provided for the user
95  * that wants to fit as many msg entries as possible in a given memory size
96  * (e.g. a memory page).
97  */
98 #define XPC_MSG_MAX_SIZE	128
99 #define XPC_MSG_HDR_MAX_SIZE	16
100 #define XPC_MSG_PAYLOAD_MAX_SIZE (XPC_MSG_MAX_SIZE - XPC_MSG_HDR_MAX_SIZE)
101 
102 #define XPC_MSG_SIZE(_payload_size) \
103 				ALIGN(XPC_MSG_HDR_MAX_SIZE + (_payload_size), \
104 				      is_uv() ? 64 : 128)
105 
106 
107 /*
108  * Define the return values and values passed to user's callout functions.
109  * (It is important to add new value codes at the end just preceding
110  * xpUnknownReason, which must have the highest numerical value.)
111  */
112 enum xp_retval {
113 	xpSuccess = 0,
114 
115 	xpNotConnected,		/*  1: channel is not connected */
116 	xpConnected,		/*  2: channel connected (opened) */
117 	xpRETIRED1,		/*  3: (formerly xpDisconnected) */
118 
119 	xpMsgReceived,		/*  4: message received */
120 	xpMsgDelivered,		/*  5: message delivered and acknowledged */
121 
122 	xpRETIRED2,		/*  6: (formerly xpTransferFailed) */
123 
124 	xpNoWait,		/*  7: operation would require wait */
125 	xpRetry,		/*  8: retry operation */
126 	xpTimeout,		/*  9: timeout in xpc_allocate_msg_wait() */
127 	xpInterrupted,		/* 10: interrupted wait */
128 
129 	xpUnequalMsgSizes,	/* 11: message size disparity between sides */
130 	xpInvalidAddress,	/* 12: invalid address */
131 
132 	xpNoMemory,		/* 13: no memory available for XPC structures */
133 	xpLackOfResources,	/* 14: insufficient resources for operation */
134 	xpUnregistered,		/* 15: channel is not registered */
135 	xpAlreadyRegistered,	/* 16: channel is already registered */
136 
137 	xpPartitionDown,	/* 17: remote partition is down */
138 	xpNotLoaded,		/* 18: XPC module is not loaded */
139 	xpUnloading,		/* 19: this side is unloading XPC module */
140 
141 	xpBadMagic,		/* 20: XPC MAGIC string not found */
142 
143 	xpReactivating,		/* 21: remote partition was reactivated */
144 
145 	xpUnregistering,	/* 22: this side is unregistering channel */
146 	xpOtherUnregistering,	/* 23: other side is unregistering channel */
147 
148 	xpCloneKThread,		/* 24: cloning kernel thread */
149 	xpCloneKThreadFailed,	/* 25: cloning kernel thread failed */
150 
151 	xpNoHeartbeat,		/* 26: remote partition has no heartbeat */
152 
153 	xpPioReadError,		/* 27: PIO read error */
154 	xpPhysAddrRegFailed,	/* 28: registration of phys addr range failed */
155 
156 	xpRETIRED3,		/* 29: (formerly xpBteDirectoryError) */
157 	xpRETIRED4,		/* 30: (formerly xpBtePoisonError) */
158 	xpRETIRED5,		/* 31: (formerly xpBteWriteError) */
159 	xpRETIRED6,		/* 32: (formerly xpBteAccessError) */
160 	xpRETIRED7,		/* 33: (formerly xpBtePWriteError) */
161 	xpRETIRED8,		/* 34: (formerly xpBtePReadError) */
162 	xpRETIRED9,		/* 35: (formerly xpBteTimeOutError) */
163 	xpRETIRED10,		/* 36: (formerly xpBteXtalkError) */
164 	xpRETIRED11,		/* 37: (formerly xpBteNotAvailable) */
165 	xpRETIRED12,		/* 38: (formerly xpBteUnmappedError) */
166 
167 	xpBadVersion,		/* 39: bad version number */
168 	xpVarsNotSet,		/* 40: the XPC variables are not set up */
169 	xpNoRsvdPageAddr,	/* 41: unable to get rsvd page's phys addr */
170 	xpInvalidPartid,	/* 42: invalid partition ID */
171 	xpLocalPartid,		/* 43: local partition ID */
172 
173 	xpOtherGoingDown,	/* 44: other side going down, reason unknown */
174 	xpSystemGoingDown,	/* 45: system is going down, reason unknown */
175 	xpSystemHalt,		/* 46: system is being halted */
176 	xpSystemReboot,		/* 47: system is being rebooted */
177 	xpSystemPoweroff,	/* 48: system is being powered off */
178 
179 	xpDisconnecting,	/* 49: channel disconnecting (closing) */
180 
181 	xpOpenCloseError,	/* 50: channel open/close protocol error */
182 
183 	xpDisconnected,		/* 51: channel disconnected (closed) */
184 
185 	xpBteCopyError,		/* 52: bte_copy() returned error */
186 	xpSalError,		/* 53: sn SAL error */
187 	xpRsvdPageNotSet,	/* 54: the reserved page is not set up */
188 	xpPayloadTooBig,	/* 55: payload too large for message slot */
189 
190 	xpUnsupported,		/* 56: unsupported functionality or resource */
191 	xpNeedMoreInfo,		/* 57: more info is needed by SAL */
192 
193 	xpGruCopyError,		/* 58: gru_copy_gru() returned error */
194 	xpGruSendMqError,	/* 59: gru send message queue related error */
195 
196 	xpBadChannelNumber,	/* 60: invalid channel number */
197 	xpBadMsgType,		/* 61: invalid message type */
198 	xpBiosError,		/* 62: BIOS error */
199 
200 	xpUnknownReason		/* 63: unknown reason - must be last in enum */
201 };
202 
203 /*
204  * Define the callout function type used by XPC to update the user on
205  * connection activity and state changes via the user function registered
206  * by xpc_connect().
207  *
208  * Arguments:
209  *
210  *	reason - reason code.
211  *	partid - partition ID associated with condition.
212  *	ch_number - channel # associated with condition.
213  *	data - pointer to optional data.
214  *	key - pointer to optional user-defined value provided as the "key"
215  *	      argument to xpc_connect().
216  *
217  * A reason code of xpConnected indicates that a connection has been
218  * established to the specified partition on the specified channel. The data
219  * argument indicates the max number of entries allowed in the message queue.
220  *
221  * A reason code of xpMsgReceived indicates that a XPC message arrived from
222  * the specified partition on the specified channel. The data argument
223  * specifies the address of the message's payload. The user must call
224  * xpc_received() when finished with the payload.
225  *
226  * All other reason codes indicate failure. The data argmument is NULL.
227  * When a failure reason code is received, one can assume that the channel
228  * is not connected.
229  */
230 typedef void (*xpc_channel_func) (enum xp_retval reason, short partid,
231 				  int ch_number, void *data, void *key);
232 
233 /*
234  * Define the callout function type used by XPC to notify the user of
235  * messages received and delivered via the user function registered by
236  * xpc_send_notify().
237  *
238  * Arguments:
239  *
240  *	reason - reason code.
241  *	partid - partition ID associated with condition.
242  *	ch_number - channel # associated with condition.
243  *	key - pointer to optional user-defined value provided as the "key"
244  *	      argument to xpc_send_notify().
245  *
246  * A reason code of xpMsgDelivered indicates that the message was delivered
247  * to the intended recipient and that they have acknowledged its receipt by
248  * calling xpc_received().
249  *
250  * All other reason codes indicate failure.
251  *
252  * NOTE: The user defined function must be callable by an interrupt handler
253  *       and thus cannot block.
254  */
255 typedef void (*xpc_notify_func) (enum xp_retval reason, short partid,
256 				 int ch_number, void *key);
257 
258 /*
259  * The following is a registration entry. There is a global array of these,
260  * one per channel. It is used to record the connection registration made
261  * by the users of XPC. As long as a registration entry exists, for any
262  * partition that comes up, XPC will attempt to establish a connection on
263  * that channel. Notification that a connection has been made will occur via
264  * the xpc_channel_func function.
265  *
266  * The 'func' field points to the function to call when aynchronous
267  * notification is required for such events as: a connection established/lost,
268  * or an incoming message received, or an error condition encountered. A
269  * non-NULL 'func' field indicates that there is an active registration for
270  * the channel.
271  */
272 struct xpc_registration {
273 	struct mutex mutex;
274 	xpc_channel_func func;	/* function to call */
275 	void *key;		/* pointer to user's key */
276 	u16 nentries;		/* #of msg entries in local msg queue */
277 	u16 entry_size;		/* message queue's message entry size */
278 	u32 assigned_limit;	/* limit on #of assigned kthreads */
279 	u32 idle_limit;		/* limit on #of idle kthreads */
280 } ____cacheline_aligned;
281 
282 #define XPC_CHANNEL_REGISTERED(_c)	(xpc_registrations[_c].func != NULL)
283 
284 /* the following are valid xpc_send() or xpc_send_notify() flags */
285 #define XPC_WAIT	0	/* wait flag */
286 #define XPC_NOWAIT	1	/* no wait flag */
287 
288 struct xpc_interface {
289 	void (*connect) (int);
290 	void (*disconnect) (int);
291 	enum xp_retval (*send) (short, int, u32, void *, u16);
292 	enum xp_retval (*send_notify) (short, int, u32, void *, u16,
293 					xpc_notify_func, void *);
294 	void (*received) (short, int, void *);
295 	enum xp_retval (*partid_to_nasids) (short, void *);
296 };
297 
298 extern struct xpc_interface xpc_interface;
299 
300 extern void xpc_set_interface(void (*)(int),
301 			      void (*)(int),
302 			      enum xp_retval (*)(short, int, u32, void *, u16),
303 			      enum xp_retval (*)(short, int, u32, void *, u16,
304 						 xpc_notify_func, void *),
305 			      void (*)(short, int, void *),
306 			      enum xp_retval (*)(short, void *));
307 extern void xpc_clear_interface(void);
308 
309 extern enum xp_retval xpc_connect(int, xpc_channel_func, void *, u16,
310 				   u16, u32, u32);
311 extern void xpc_disconnect(int);
312 
313 static inline enum xp_retval
314 xpc_send(short partid, int ch_number, u32 flags, void *payload,
315 	 u16 payload_size)
316 {
317 	return xpc_interface.send(partid, ch_number, flags, payload,
318 				  payload_size);
319 }
320 
321 static inline enum xp_retval
322 xpc_send_notify(short partid, int ch_number, u32 flags, void *payload,
323 		u16 payload_size, xpc_notify_func func, void *key)
324 {
325 	return xpc_interface.send_notify(partid, ch_number, flags, payload,
326 					 payload_size, func, key);
327 }
328 
329 static inline void
330 xpc_received(short partid, int ch_number, void *payload)
331 {
332 	return xpc_interface.received(partid, ch_number, payload);
333 }
334 
335 static inline enum xp_retval
336 xpc_partid_to_nasids(short partid, void *nasids)
337 {
338 	return xpc_interface.partid_to_nasids(partid, nasids);
339 }
340 
341 extern short xp_max_npartitions;
342 extern short xp_partition_id;
343 extern u8 xp_region_size;
344 
345 extern unsigned long (*xp_pa) (void *);
346 extern enum xp_retval (*xp_remote_memcpy) (unsigned long, const unsigned long,
347 		       size_t);
348 extern int (*xp_cpu_to_nasid) (int);
349 extern enum xp_retval (*xp_expand_memprotect) (unsigned long, unsigned long);
350 extern enum xp_retval (*xp_restrict_memprotect) (unsigned long, unsigned long);
351 
352 extern u64 xp_nofault_PIOR_target;
353 extern int xp_nofault_PIOR(void *);
354 extern int xp_error_PIOR(void);
355 
356 extern struct device *xp;
357 extern enum xp_retval xp_init_sn2(void);
358 extern enum xp_retval xp_init_uv(void);
359 extern void xp_exit_sn2(void);
360 extern void xp_exit_uv(void);
361 
362 #endif /* _DRIVERS_MISC_SGIXP_XP_H */
363