xref: /openbmc/linux/drivers/misc/sgi-xp/xp.h (revision e3b9f1e8)
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/sn/arch.h>	/* defines is_shub1() and is_shub2() */
29 #define is_shub()	ia64_platform_is("sn2")
30 #endif
31 
32 #ifndef is_shub1
33 #define is_shub1()	0
34 #endif
35 
36 #ifndef is_shub2
37 #define is_shub2()	0
38 #endif
39 
40 #ifndef is_shub
41 #define is_shub()	0
42 #endif
43 
44 #ifdef USE_DBUG_ON
45 #define DBUG_ON(condition)	BUG_ON(condition)
46 #else
47 #define DBUG_ON(condition)
48 #endif
49 
50 /*
51  * Define the maximum number of partitions the system can possibly support.
52  * It is based on the maximum number of hardware partitionable regions. The
53  * term 'region' in this context refers to the minimum number of nodes that
54  * can comprise an access protection grouping. The access protection is in
55  * regards to memory, IPI and IOI.
56  *
57  * The maximum number of hardware partitionable regions is equal to the
58  * maximum number of nodes in the entire system divided by the minimum number
59  * of nodes that comprise an access protection grouping.
60  */
61 #define XP_MAX_NPARTITIONS_SN2	64
62 #define XP_MAX_NPARTITIONS_UV	256
63 
64 /*
65  * XPC establishes channel connections between the local partition and any
66  * other partition that is currently up. Over these channels, kernel-level
67  * `users' can communicate with their counterparts on the other partitions.
68  *
69  * If the need for additional channels arises, one can simply increase
70  * XPC_MAX_NCHANNELS accordingly. If the day should come where that number
71  * exceeds the absolute MAXIMUM number of channels possible (eight), then one
72  * will need to make changes to the XPC code to accommodate for this.
73  *
74  * The absolute maximum number of channels possible is limited to eight for
75  * performance reasons on sn2 hardware. The internal cross partition structures
76  * require sixteen bytes per channel, and eight allows all of this
77  * interface-shared info to fit in one 128-byte cacheline.
78  */
79 #define XPC_MEM_CHANNEL		0	/* memory channel number */
80 #define	XPC_NET_CHANNEL		1	/* network channel number */
81 
82 #define XPC_MAX_NCHANNELS	2	/* max #of channels allowed */
83 
84 #if XPC_MAX_NCHANNELS > 8
85 #error	XPC_MAX_NCHANNELS exceeds absolute MAXIMUM possible.
86 #endif
87 
88 /*
89  * Define macro, XPC_MSG_SIZE(), is provided for the user
90  * that wants to fit as many msg entries as possible in a given memory size
91  * (e.g. a memory page).
92  */
93 #define XPC_MSG_MAX_SIZE	128
94 #define XPC_MSG_HDR_MAX_SIZE	16
95 #define XPC_MSG_PAYLOAD_MAX_SIZE (XPC_MSG_MAX_SIZE - XPC_MSG_HDR_MAX_SIZE)
96 
97 #define XPC_MSG_SIZE(_payload_size) \
98 				ALIGN(XPC_MSG_HDR_MAX_SIZE + (_payload_size), \
99 				      is_uv() ? 64 : 128)
100 
101 
102 /*
103  * Define the return values and values passed to user's callout functions.
104  * (It is important to add new value codes at the end just preceding
105  * xpUnknownReason, which must have the highest numerical value.)
106  */
107 enum xp_retval {
108 	xpSuccess = 0,
109 
110 	xpNotConnected,		/*  1: channel is not connected */
111 	xpConnected,		/*  2: channel connected (opened) */
112 	xpRETIRED1,		/*  3: (formerly xpDisconnected) */
113 
114 	xpMsgReceived,		/*  4: message received */
115 	xpMsgDelivered,		/*  5: message delivered and acknowledged */
116 
117 	xpRETIRED2,		/*  6: (formerly xpTransferFailed) */
118 
119 	xpNoWait,		/*  7: operation would require wait */
120 	xpRetry,		/*  8: retry operation */
121 	xpTimeout,		/*  9: timeout in xpc_allocate_msg_wait() */
122 	xpInterrupted,		/* 10: interrupted wait */
123 
124 	xpUnequalMsgSizes,	/* 11: message size disparity between sides */
125 	xpInvalidAddress,	/* 12: invalid address */
126 
127 	xpNoMemory,		/* 13: no memory available for XPC structures */
128 	xpLackOfResources,	/* 14: insufficient resources for operation */
129 	xpUnregistered,		/* 15: channel is not registered */
130 	xpAlreadyRegistered,	/* 16: channel is already registered */
131 
132 	xpPartitionDown,	/* 17: remote partition is down */
133 	xpNotLoaded,		/* 18: XPC module is not loaded */
134 	xpUnloading,		/* 19: this side is unloading XPC module */
135 
136 	xpBadMagic,		/* 20: XPC MAGIC string not found */
137 
138 	xpReactivating,		/* 21: remote partition was reactivated */
139 
140 	xpUnregistering,	/* 22: this side is unregistering channel */
141 	xpOtherUnregistering,	/* 23: other side is unregistering channel */
142 
143 	xpCloneKThread,		/* 24: cloning kernel thread */
144 	xpCloneKThreadFailed,	/* 25: cloning kernel thread failed */
145 
146 	xpNoHeartbeat,		/* 26: remote partition has no heartbeat */
147 
148 	xpPioReadError,		/* 27: PIO read error */
149 	xpPhysAddrRegFailed,	/* 28: registration of phys addr range failed */
150 
151 	xpRETIRED3,		/* 29: (formerly xpBteDirectoryError) */
152 	xpRETIRED4,		/* 30: (formerly xpBtePoisonError) */
153 	xpRETIRED5,		/* 31: (formerly xpBteWriteError) */
154 	xpRETIRED6,		/* 32: (formerly xpBteAccessError) */
155 	xpRETIRED7,		/* 33: (formerly xpBtePWriteError) */
156 	xpRETIRED8,		/* 34: (formerly xpBtePReadError) */
157 	xpRETIRED9,		/* 35: (formerly xpBteTimeOutError) */
158 	xpRETIRED10,		/* 36: (formerly xpBteXtalkError) */
159 	xpRETIRED11,		/* 37: (formerly xpBteNotAvailable) */
160 	xpRETIRED12,		/* 38: (formerly xpBteUnmappedError) */
161 
162 	xpBadVersion,		/* 39: bad version number */
163 	xpVarsNotSet,		/* 40: the XPC variables are not set up */
164 	xpNoRsvdPageAddr,	/* 41: unable to get rsvd page's phys addr */
165 	xpInvalidPartid,	/* 42: invalid partition ID */
166 	xpLocalPartid,		/* 43: local partition ID */
167 
168 	xpOtherGoingDown,	/* 44: other side going down, reason unknown */
169 	xpSystemGoingDown,	/* 45: system is going down, reason unknown */
170 	xpSystemHalt,		/* 46: system is being halted */
171 	xpSystemReboot,		/* 47: system is being rebooted */
172 	xpSystemPoweroff,	/* 48: system is being powered off */
173 
174 	xpDisconnecting,	/* 49: channel disconnecting (closing) */
175 
176 	xpOpenCloseError,	/* 50: channel open/close protocol error */
177 
178 	xpDisconnected,		/* 51: channel disconnected (closed) */
179 
180 	xpBteCopyError,		/* 52: bte_copy() returned error */
181 	xpSalError,		/* 53: sn SAL error */
182 	xpRsvdPageNotSet,	/* 54: the reserved page is not set up */
183 	xpPayloadTooBig,	/* 55: payload too large for message slot */
184 
185 	xpUnsupported,		/* 56: unsupported functionality or resource */
186 	xpNeedMoreInfo,		/* 57: more info is needed by SAL */
187 
188 	xpGruCopyError,		/* 58: gru_copy_gru() returned error */
189 	xpGruSendMqError,	/* 59: gru send message queue related error */
190 
191 	xpBadChannelNumber,	/* 60: invalid channel number */
192 	xpBadMsgType,		/* 61: invalid message type */
193 	xpBiosError,		/* 62: BIOS error */
194 
195 	xpUnknownReason		/* 63: unknown reason - must be last in enum */
196 };
197 
198 /*
199  * Define the callout function type used by XPC to update the user on
200  * connection activity and state changes via the user function registered
201  * by xpc_connect().
202  *
203  * Arguments:
204  *
205  *	reason - reason code.
206  *	partid - partition ID associated with condition.
207  *	ch_number - channel # associated with condition.
208  *	data - pointer to optional data.
209  *	key - pointer to optional user-defined value provided as the "key"
210  *	      argument to xpc_connect().
211  *
212  * A reason code of xpConnected indicates that a connection has been
213  * established to the specified partition on the specified channel. The data
214  * argument indicates the max number of entries allowed in the message queue.
215  *
216  * A reason code of xpMsgReceived indicates that a XPC message arrived from
217  * the specified partition on the specified channel. The data argument
218  * specifies the address of the message's payload. The user must call
219  * xpc_received() when finished with the payload.
220  *
221  * All other reason codes indicate failure. The data argmument is NULL.
222  * When a failure reason code is received, one can assume that the channel
223  * is not connected.
224  */
225 typedef void (*xpc_channel_func) (enum xp_retval reason, short partid,
226 				  int ch_number, void *data, void *key);
227 
228 /*
229  * Define the callout function type used by XPC to notify the user of
230  * messages received and delivered via the user function registered by
231  * xpc_send_notify().
232  *
233  * Arguments:
234  *
235  *	reason - reason code.
236  *	partid - partition ID associated with condition.
237  *	ch_number - channel # associated with condition.
238  *	key - pointer to optional user-defined value provided as the "key"
239  *	      argument to xpc_send_notify().
240  *
241  * A reason code of xpMsgDelivered indicates that the message was delivered
242  * to the intended recipient and that they have acknowledged its receipt by
243  * calling xpc_received().
244  *
245  * All other reason codes indicate failure.
246  *
247  * NOTE: The user defined function must be callable by an interrupt handler
248  *       and thus cannot block.
249  */
250 typedef void (*xpc_notify_func) (enum xp_retval reason, short partid,
251 				 int ch_number, void *key);
252 
253 /*
254  * The following is a registration entry. There is a global array of these,
255  * one per channel. It is used to record the connection registration made
256  * by the users of XPC. As long as a registration entry exists, for any
257  * partition that comes up, XPC will attempt to establish a connection on
258  * that channel. Notification that a connection has been made will occur via
259  * the xpc_channel_func function.
260  *
261  * The 'func' field points to the function to call when aynchronous
262  * notification is required for such events as: a connection established/lost,
263  * or an incoming message received, or an error condition encountered. A
264  * non-NULL 'func' field indicates that there is an active registration for
265  * the channel.
266  */
267 struct xpc_registration {
268 	struct mutex mutex;
269 	xpc_channel_func func;	/* function to call */
270 	void *key;		/* pointer to user's key */
271 	u16 nentries;		/* #of msg entries in local msg queue */
272 	u16 entry_size;		/* message queue's message entry size */
273 	u32 assigned_limit;	/* limit on #of assigned kthreads */
274 	u32 idle_limit;		/* limit on #of idle kthreads */
275 } ____cacheline_aligned;
276 
277 #define XPC_CHANNEL_REGISTERED(_c)	(xpc_registrations[_c].func != NULL)
278 
279 /* the following are valid xpc_send() or xpc_send_notify() flags */
280 #define XPC_WAIT	0	/* wait flag */
281 #define XPC_NOWAIT	1	/* no wait flag */
282 
283 struct xpc_interface {
284 	void (*connect) (int);
285 	void (*disconnect) (int);
286 	enum xp_retval (*send) (short, int, u32, void *, u16);
287 	enum xp_retval (*send_notify) (short, int, u32, void *, u16,
288 					xpc_notify_func, void *);
289 	void (*received) (short, int, void *);
290 	enum xp_retval (*partid_to_nasids) (short, void *);
291 };
292 
293 extern struct xpc_interface xpc_interface;
294 
295 extern void xpc_set_interface(void (*)(int),
296 			      void (*)(int),
297 			      enum xp_retval (*)(short, int, u32, void *, u16),
298 			      enum xp_retval (*)(short, int, u32, void *, u16,
299 						 xpc_notify_func, void *),
300 			      void (*)(short, int, void *),
301 			      enum xp_retval (*)(short, void *));
302 extern void xpc_clear_interface(void);
303 
304 extern enum xp_retval xpc_connect(int, xpc_channel_func, void *, u16,
305 				   u16, u32, u32);
306 extern void xpc_disconnect(int);
307 
308 static inline enum xp_retval
309 xpc_send(short partid, int ch_number, u32 flags, void *payload,
310 	 u16 payload_size)
311 {
312 	if (!xpc_interface.send)
313 		return xpNotLoaded;
314 
315 	return xpc_interface.send(partid, ch_number, flags, payload,
316 				  payload_size);
317 }
318 
319 static inline enum xp_retval
320 xpc_send_notify(short partid, int ch_number, u32 flags, void *payload,
321 		u16 payload_size, xpc_notify_func func, void *key)
322 {
323 	if (!xpc_interface.send_notify)
324 		return xpNotLoaded;
325 
326 	return xpc_interface.send_notify(partid, ch_number, flags, payload,
327 					 payload_size, func, key);
328 }
329 
330 static inline void
331 xpc_received(short partid, int ch_number, void *payload)
332 {
333 	if (xpc_interface.received)
334 		xpc_interface.received(partid, ch_number, payload);
335 }
336 
337 static inline enum xp_retval
338 xpc_partid_to_nasids(short partid, void *nasids)
339 {
340 	if (!xpc_interface.partid_to_nasids)
341 		return xpNotLoaded;
342 
343 	return xpc_interface.partid_to_nasids(partid, nasids);
344 }
345 
346 extern short xp_max_npartitions;
347 extern short xp_partition_id;
348 extern u8 xp_region_size;
349 
350 extern unsigned long (*xp_pa) (void *);
351 extern unsigned long (*xp_socket_pa) (unsigned long);
352 extern enum xp_retval (*xp_remote_memcpy) (unsigned long, const unsigned long,
353 		       size_t);
354 extern int (*xp_cpu_to_nasid) (int);
355 extern enum xp_retval (*xp_expand_memprotect) (unsigned long, unsigned long);
356 extern enum xp_retval (*xp_restrict_memprotect) (unsigned long, unsigned long);
357 
358 extern u64 xp_nofault_PIOR_target;
359 extern int xp_nofault_PIOR(void *);
360 extern int xp_error_PIOR(void);
361 
362 extern struct device *xp;
363 extern enum xp_retval xp_init_sn2(void);
364 extern enum xp_retval xp_init_uv(void);
365 extern void xp_exit_sn2(void);
366 extern void xp_exit_uv(void);
367 
368 #endif /* _DRIVERS_MISC_SGIXP_XP_H */
369