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/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,           /* 60: invalid message type */
 198
 199         xpUnknownReason         /* 61: unknown reason - must be last in enum */
 200 };
 201
 202 /*
 203  * Define the callout function type used by XPC to update the user on
 204  * connection activity and state changes via the user function registered
 205  * by xpc_connect().
 206  *
 207  * Arguments:
 208  *
 209  *      reason - reason code.
 210  *      partid - partition ID associated with condition.
 211  *      ch_number - channel # associated with condition.
 212  *      data - pointer to optional data.
 213  *      key - pointer to optional user-defined value provided as the "key"
 214  *            argument to xpc_connect().
 215  *
 216  * A reason code of xpConnected indicates that a connection has been
 217  * established to the specified partition on the specified channel. The data
 218  * argument indicates the max number of entries allowed in the message queue.
 219  *
 220  * A reason code of xpMsgReceived indicates that a XPC message arrived from
 221  * the specified partition on the specified channel. The data argument
 222  * specifies the address of the message's payload. The user must call
 223  * xpc_received() when finished with the payload.
 224  *
 225  * All other reason codes indicate failure. The data argmument is NULL.
 226  * When a failure reason code is received, one can assume that the channel
 227  * is not connected.
 228  */
 229 typedef void (*xpc_channel_func) (enum xp_retval reason, short partid,
 230                                   int ch_number, void *data, void *key);
 231
 232 /*
 233  * Define the callout function type used by XPC to notify the user of
 234  * messages received and delivered via the user function registered by
 235  * xpc_send_notify().
 236  *
 237  * Arguments:
 238  *
 239  *      reason - reason code.
 240  *      partid - partition ID associated with condition.
 241  *      ch_number - channel # associated with condition.
 242  *      key - pointer to optional user-defined value provided as the "key"
 243  *            argument to xpc_send_notify().
 244  *
 245  * A reason code of xpMsgDelivered indicates that the message was delivered
 246  * to the intended recipient and that they have acknowledged its receipt by
 247  * calling xpc_received().
 248  *
 249  * All other reason codes indicate failure.
 250  *
 251  * NOTE: The user defined function must be callable by an interrupt handler
 252  *       and thus cannot block.
 253  */
 254 typedef void (*xpc_notify_func) (enum xp_retval reason, short partid,
 255                                  int ch_number, void *key);
 256
 257 /*
 258  * The following is a registration entry. There is a global array of these,
 259  * one per channel. It is used to record the connection registration made
 260  * by the users of XPC. As long as a registration entry exists, for any
 261  * partition that comes up, XPC will attempt to establish a connection on
 262  * that channel. Notification that a connection has been made will occur via
 263  * the xpc_channel_func function.
 264  *
 265  * The 'func' field points to the function to call when aynchronous
 266  * notification is required for such events as: a connection established/lost,
 267  * or an incoming message received, or an error condition encountered. A
 268  * non-NULL 'func' field indicates that there is an active registration for
 269  * the channel.
 270  */
 271 struct xpc_registration {
 272         struct mutex mutex;
 273         xpc_channel_func func;  /* function to call */
 274         void *key;              /* pointer to user's key */
 275         u16 nentries;           /* #of msg entries in local msg queue */
 276         u16 entry_size;         /* message queue's message entry size */
 277         u32 assigned_limit;     /* limit on #of assigned kthreads */
 278         u32 idle_limit;         /* limit on #of idle kthreads */
 279 } ____cacheline_aligned;
 280
 281 #define XPC_CHANNEL_REGISTERED(_c)      (xpc_registrations[_c].func != NULL)
 282
 283 /* the following are valid xpc_send() or xpc_send_notify() flags */
 284 #define XPC_WAIT        0       /* wait flag */
 285 #define XPC_NOWAIT      1       /* no wait flag */
 286
 287 struct xpc_interface {
 288         void (*connect) (int);
 289         void (*disconnect) (int);
 290         enum xp_retval (*send) (short, int, u32, void *, u16);
 291         enum xp_retval (*send_notify) (short, int, u32, void *, u16,
 292                                         xpc_notify_func, void *);
 293         void (*received) (short, int, void *);
 294         enum xp_retval (*partid_to_nasids) (short, void *);
 295 };
 296
 297 extern struct xpc_interface xpc_interface;
 298
 299 extern void xpc_set_interface(void (*)(int),
 300                               void (*)(int),
 301                               enum xp_retval (*)(short, int, u32, void *, u16),
 302                               enum xp_retval (*)(short, int, u32, void *, u16,
 303                                                  xpc_notify_func, void *),
 304                               void (*)(short, int, void *),
 305                               enum xp_retval (*)(short, void *));
 306 extern void xpc_clear_interface(void);
 307
 308 extern enum xp_retval xpc_connect(int, xpc_channel_func, void *, u16,
 309                                    u16, u32, u32);
 310 extern void xpc_disconnect(int);
 311
 312 static inline enum xp_retval
 313 xpc_send(short partid, int ch_number, u32 flags, void *payload,
 314          u16 payload_size)
 315 {
 316         return xpc_interface.send(partid, ch_number, flags, payload,
 317                                   payload_size);
 318 }
 319
 320 static inline enum xp_retval
 321 xpc_send_notify(short partid, int ch_number, u32 flags, void *payload,
 322                 u16 payload_size, xpc_notify_func func, void *key)
 323 {
 324         return xpc_interface.send_notify(partid, ch_number, flags, payload,
 325                                          payload_size, func, key);
 326 }
 327
 328 static inline void
 329 xpc_received(short partid, int ch_number, void *payload)
 330 {
 331         return xpc_interface.received(partid, ch_number, payload);
 332 }
 333
 334 static inline enum xp_retval
 335 xpc_partid_to_nasids(short partid, void *nasids)
 336 {
 337         return xpc_interface.partid_to_nasids(partid, nasids);
 338 }
 339
 340 extern short xp_max_npartitions;
 341 extern short xp_partition_id;
 342 extern u8 xp_region_size;
 343
 344 extern unsigned long (*xp_pa) (void *);
 345 extern enum xp_retval (*xp_remote_memcpy) (unsigned long, const unsigned long,
 346                        size_t);
 347 extern int (*xp_cpu_to_nasid) (int);
 348
 349 extern u64 xp_nofault_PIOR_target;
 350 extern int xp_nofault_PIOR(void *);
 351 extern int xp_error_PIOR(void);
 352
 353 extern struct device *xp;
 354 extern enum xp_retval xp_init_sn2(void);
 355 extern enum xp_retval xp_init_uv(void);
 356 extern void xp_exit_sn2(void);
 357 extern void xp_exit_uv(void);
 358
 359 #endif /* _DRIVERS_MISC_SGIXP_XP_H */