drivers/misc/sgi-xp/xp.h

   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/cache.h>
  17 #include <linux/hardirq.h>
  18 #include <linux/mutex.h>
  19 #include <asm/sn/types.h>
  20 #ifdef CONFIG_IA64
  21 #include <asm/sn/arch.h>
  22 #endif
  23
  24 /* ??? Add this #define to some linux header file some day? */
  25 #define BYTES_PER_WORD  sizeof(void *)
  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 #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()       (is_shub1() || is_shub2())
  43 #endif
  44
  45 #ifndef is_uv
  46 #define is_uv()         0
  47 #endif
  48
  49 /*
  50  * Define the maximum number of partitions the system can possibly support.
  51  * It is based on the maximum number of hardware partitionable regions. The
  52  * term 'region' in this context refers to the minimum number of nodes that
  53  * can comprise an access protection grouping. The access protection is in
  54  * regards to memory, IPI and IOI.
  55  *
  56  * The maximum number of hardware partitionable regions is equal to the
  57  * maximum number of nodes in the entire system divided by the minimum number
  58  * of nodes that comprise an access protection grouping.
  59  */
  60 #define XP_MAX_NPARTITIONS_SN2  64
  61 #define XP_MAX_NPARTITIONS_UV   256
  62
  63 /*
  64  * XPC establishes channel connections between the local partition and any
  65  * other partition that is currently up. Over these channels, kernel-level
  66  * `users' can communicate with their counterparts on the other partitions.
  67  *
  68  * If the need for additional channels arises, one can simply increase
  69  * XPC_MAX_NCHANNELS accordingly. If the day should come where that number
  70  * exceeds the absolute MAXIMUM number of channels possible (eight), then one
  71  * will need to make changes to the XPC code to accommodate for this.
  72  *
  73  * The absolute maximum number of channels possible is limited to eight for
  74  * performance reasons on sn2 hardware. The internal cross partition structures
  75  * require sixteen bytes per channel, and eight allows all of this
  76  * interface-shared info to fit in one 128-byte cacheline.
  77  */
  78 #define XPC_MEM_CHANNEL         0       /* memory channel number */
  79 #define XPC_NET_CHANNEL         1       /* network channel number */
  80
  81 #define XPC_MAX_NCHANNELS       2       /* max #of channels allowed */
  82
  83 #if XPC_MAX_NCHANNELS > 8
  84 #error  XPC_MAX_NCHANNELS exceeds absolute MAXIMUM possible.
  85 #endif
  86
  87 /*
  88  * The format of an XPC message is as follows:
  89  *
  90  *      +-------+--------------------------------+
  91  *      | flags |////////////////////////////////|
  92  *      +-------+--------------------------------+
  93  *      |             message #                  |
  94  *      +----------------------------------------+
  95  *      |     payload (user-defined message)     |
  96  *      |                                        |
  97  *                      :
  98  *      |                                        |
  99  *      +----------------------------------------+
 100  *
 101  * The size of the payload is defined by the user via xpc_connect(). A user-
 102  * defined message resides in the payload area.
 103  *
 104  * The size of a message entry (within a message queue) must be a cacheline
 105  * sized multiple in order to facilitate the BTE transfer of messages from one
 106  * message queue to another. A macro, XPC_MSG_SIZE(), is provided for the user
 107  * that wants to fit as many msg entries as possible in a given memory size
 108  * (e.g. a memory page).
 109  */
 110 struct xpc_msg {
 111         u8 flags;               /* FOR XPC INTERNAL USE ONLY */
 112         u8 reserved[7];         /* FOR XPC INTERNAL USE ONLY */
 113         s64 number;             /* FOR XPC INTERNAL USE ONLY */
 114
 115         u64 payload;            /* user defined portion of message */
 116 };
 117
 118 #define XPC_MSG_PAYLOAD_OFFSET  (u64) (&((struct xpc_msg *)0)->payload)
 119 #define XPC_MSG_SIZE(_payload_size) \
 120                 L1_CACHE_ALIGN(XPC_MSG_PAYLOAD_OFFSET + (_payload_size))
 121
 122 /*
 123  * Define the return values and values passed to user's callout functions.
 124  * (It is important to add new value codes at the end just preceding
 125  * xpUnknownReason, which must have the highest numerical value.)
 126  */
 127 enum xp_retval {
 128         xpSuccess = 0,
 129
 130         xpNotConnected,         /*  1: channel is not connected */
 131         xpConnected,            /*  2: channel connected (opened) */
 132         xpRETIRED1,             /*  3: (formerly xpDisconnected) */
 133
 134         xpMsgReceived,          /*  4: message received */
 135         xpMsgDelivered,         /*  5: message delivered and acknowledged */
 136
 137         xpRETIRED2,             /*  6: (formerly xpTransferFailed) */
 138
 139         xpNoWait,               /*  7: operation would require wait */
 140         xpRetry,                /*  8: retry operation */
 141         xpTimeout,              /*  9: timeout in xpc_allocate_msg_wait() */
 142         xpInterrupted,          /* 10: interrupted wait */
 143
 144         xpUnequalMsgSizes,      /* 11: message size disparity between sides */
 145         xpInvalidAddress,       /* 12: invalid address */
 146
 147         xpNoMemory,             /* 13: no memory available for XPC structures */
 148         xpLackOfResources,      /* 14: insufficient resources for operation */
 149         xpUnregistered,         /* 15: channel is not registered */
 150         xpAlreadyRegistered,    /* 16: channel is already registered */
 151
 152         xpPartitionDown,        /* 17: remote partition is down */
 153         xpNotLoaded,            /* 18: XPC module is not loaded */
 154         xpUnloading,            /* 19: this side is unloading XPC module */
 155
 156         xpBadMagic,             /* 20: XPC MAGIC string not found */
 157
 158         xpReactivating,         /* 21: remote partition was reactivated */
 159
 160         xpUnregistering,        /* 22: this side is unregistering channel */
 161         xpOtherUnregistering,   /* 23: other side is unregistering channel */
 162
 163         xpCloneKThread,         /* 24: cloning kernel thread */
 164         xpCloneKThreadFailed,   /* 25: cloning kernel thread failed */
 165
 166         xpNoHeartbeat,          /* 26: remote partition has no heartbeat */
 167
 168         xpPioReadError,         /* 27: PIO read error */
 169         xpPhysAddrRegFailed,    /* 28: registration of phys addr range failed */
 170
 171         xpRETIRED3,             /* 29: (formerly xpBteDirectoryError) */
 172         xpRETIRED4,             /* 30: (formerly xpBtePoisonError) */
 173         xpRETIRED5,             /* 31: (formerly xpBteWriteError) */
 174         xpRETIRED6,             /* 32: (formerly xpBteAccessError) */
 175         xpRETIRED7,             /* 33: (formerly xpBtePWriteError) */
 176         xpRETIRED8,             /* 34: (formerly xpBtePReadError) */
 177         xpRETIRED9,             /* 35: (formerly xpBteTimeOutError) */
 178         xpRETIRED10,            /* 36: (formerly xpBteXtalkError) */
 179         xpRETIRED11,            /* 37: (formerly xpBteNotAvailable) */
 180         xpRETIRED12,            /* 38: (formerly xpBteUnmappedError) */
 181
 182         xpBadVersion,           /* 39: bad version number */
 183         xpVarsNotSet,           /* 40: the XPC variables are not set up */
 184         xpNoRsvdPageAddr,       /* 41: unable to get rsvd page's phys addr */
 185         xpInvalidPartid,        /* 42: invalid partition ID */
 186         xpLocalPartid,          /* 43: local partition ID */
 187
 188         xpOtherGoingDown,       /* 44: other side going down, reason unknown */
 189         xpSystemGoingDown,      /* 45: system is going down, reason unknown */
 190         xpSystemHalt,           /* 46: system is being halted */
 191         xpSystemReboot,         /* 47: system is being rebooted */
 192         xpSystemPoweroff,       /* 48: system is being powered off */
 193
 194         xpDisconnecting,        /* 49: channel disconnecting (closing) */
 195
 196         xpOpenCloseError,       /* 50: channel open/close protocol error */
 197
 198         xpDisconnected,         /* 51: channel disconnected (closed) */
 199
 200         xpBteCopyError,         /* 52: bte_copy() returned error */
 201         xpSalError,             /* 53: sn SAL error */
 202         xpRsvdPageNotSet,       /* 54: the reserved page is not set up */
 203         xpPayloadTooBig,        /* 55: payload too large for message slot */
 204
 205         xpUnsupported,          /* 56: unsupported functionality or resource */
 206         xpUnknownReason         /* 57: unknown reason - must be last in enum */
 207 };
 208
 209 /*
 210  * Define the callout function type used by XPC to update the user on
 211  * connection activity and state changes via the user function registered
 212  * by xpc_connect().
 213  *
 214  * Arguments:
 215  *
 216  *      reason - reason code.
 217  *      partid - partition ID associated with condition.
 218  *      ch_number - channel # associated with condition.
 219  *      data - pointer to optional data.
 220  *      key - pointer to optional user-defined value provided as the "key"
 221  *            argument to xpc_connect().
 222  *
 223  * A reason code of xpConnected indicates that a connection has been
 224  * established to the specified partition on the specified channel. The data
 225  * argument indicates the max number of entries allowed in the message queue.
 226  *
 227  * A reason code of xpMsgReceived indicates that a XPC message arrived from
 228  * the specified partition on the specified channel. The data argument
 229  * specifies the address of the message's payload. The user must call
 230  * xpc_received() when finished with the payload.
 231  *
 232  * All other reason codes indicate failure. The data argmument is NULL.
 233  * When a failure reason code is received, one can assume that the channel
 234  * is not connected.
 235  */
 236 typedef void (*xpc_channel_func) (enum xp_retval reason, short partid,
 237                                   int ch_number, void *data, void *key);
 238
 239 /*
 240  * Define the callout function type used by XPC to notify the user of
 241  * messages received and delivered via the user function registered by
 242  * xpc_send_notify().
 243  *
 244  * Arguments:
 245  *
 246  *      reason - reason code.
 247  *      partid - partition ID associated with condition.
 248  *      ch_number - channel # associated with condition.
 249  *      key - pointer to optional user-defined value provided as the "key"
 250  *            argument to xpc_send_notify().
 251  *
 252  * A reason code of xpMsgDelivered indicates that the message was delivered
 253  * to the intended recipient and that they have acknowledged its receipt by
 254  * calling xpc_received().
 255  *
 256  * All other reason codes indicate failure.
 257  */
 258 typedef void (*xpc_notify_func) (enum xp_retval reason, short partid,
 259                                  int ch_number, void *key);
 260
 261 /*
 262  * The following is a registration entry. There is a global array of these,
 263  * one per channel. It is used to record the connection registration made
 264  * by the users of XPC. As long as a registration entry exists, for any
 265  * partition that comes up, XPC will attempt to establish a connection on
 266  * that channel. Notification that a connection has been made will occur via
 267  * the xpc_channel_func function.
 268  *
 269  * The 'func' field points to the function to call when aynchronous
 270  * notification is required for such events as: a connection established/lost,
 271  * or an incoming message received, or an error condition encountered. A
 272  * non-NULL 'func' field indicates that there is an active registration for
 273  * the channel.
 274  */
 275 struct xpc_registration {
 276         struct mutex mutex;
 277         xpc_channel_func func;  /* function to call */
 278         void *key;              /* pointer to user's key */
 279         u16 nentries;           /* #of msg entries in local msg queue */
 280         u16 msg_size;           /* message queue's message size */
 281         u32 assigned_limit;     /* limit on #of assigned kthreads */
 282         u32 idle_limit;         /* limit on #of idle kthreads */
 283 } ____cacheline_aligned;
 284
 285 #define XPC_CHANNEL_REGISTERED(_c)      (xpc_registrations[_c].func != NULL)
 286
 287 /* the following are valid xpc_send() or xpc_send_notify() flags */
 288 #define XPC_WAIT        0       /* wait flag */
 289 #define XPC_NOWAIT      1       /* no wait flag */
 290
 291 struct xpc_interface {
 292         void (*connect) (int);
 293         void (*disconnect) (int);
 294         enum xp_retval (*send) (short, int, u32, void *, u16);
 295         enum xp_retval (*send_notify) (short, int, u32, void *, u16,
 296                                         xpc_notify_func, void *);
 297         void (*received) (short, int, void *);
 298         enum xp_retval (*partid_to_nasids) (short, void *);
 299 };
 300
 301 extern struct xpc_interface xpc_interface;
 302
 303 extern void xpc_set_interface(void (*)(int),
 304                               void (*)(int),
 305                               enum xp_retval (*)(short, int, u32, void *, u16),
 306                               enum xp_retval (*)(short, int, u32, void *, u16,
 307                                                  xpc_notify_func, void *),
 308                               void (*)(short, int, void *),
 309                               enum xp_retval (*)(short, void *));
 310 extern void xpc_clear_interface(void);
 311
 312 extern enum xp_retval xpc_connect(int, xpc_channel_func, void *, u16,
 313                                    u16, u32, u32);
 314 extern void xpc_disconnect(int);
 315
 316 static inline enum xp_retval
 317 xpc_send(short partid, int ch_number, u32 flags, void *payload,
 318          u16 payload_size)
 319 {
 320         return xpc_interface.send(partid, ch_number, flags, payload,
 321                                   payload_size);
 322 }
 323
 324 static inline enum xp_retval
 325 xpc_send_notify(short partid, int ch_number, u32 flags, void *payload,
 326                 u16 payload_size, xpc_notify_func func, void *key)
 327 {
 328         return xpc_interface.send_notify(partid, ch_number, flags, payload,
 329                                          payload_size, func, key);
 330 }
 331
 332 static inline void
 333 xpc_received(short partid, int ch_number, void *payload)
 334 {
 335         return xpc_interface.received(partid, ch_number, payload);
 336 }
 337
 338 static inline enum xp_retval
 339 xpc_partid_to_nasids(short partid, void *nasids)
 340 {
 341         return xpc_interface.partid_to_nasids(partid, nasids);
 342 }
 343
 344 extern short xp_max_npartitions;
 345
 346 extern enum xp_retval (*xp_remote_memcpy) (void *, const void *, size_t);
 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 */