arch/tile/include/asm/spinlock_types.h

   1 /*
   2  * Copyright 2010 Tilera Corporation. All Rights Reserved.
   3  *
   4  *   This program is free software; you can redistribute it and/or
   5  *   modify it under the terms of the GNU General Public License
   6  *   as published by the Free Software Foundation, version 2.
   7  *
   8  *   This program is distributed in the hope that it will be useful, but
   9  *   WITHOUT ANY WARRANTY; without even the implied warranty of
  10  *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  11  *   NON INFRINGEMENT.  See the GNU General Public License for
  12  *   more details.
  13  */
  14
  15 #ifndef _ASM_TILE_SPINLOCK_TYPES_H
  16 #define _ASM_TILE_SPINLOCK_TYPES_H
  17
  18 #ifndef __LINUX_SPINLOCK_TYPES_H
  19 # error "please don't include this file directly"
  20 #endif
  21
  22 #ifdef __tilegx__
  23
  24 /* Low 15 bits are "next"; high 15 bits are "current". */
  25 typedef struct arch_spinlock {
  26         unsigned int lock;
  27 } arch_spinlock_t;
  28
  29 #define __ARCH_SPIN_LOCK_UNLOCKED       { 0 }
  30
  31 /* High bit is "writer owns"; low 31 bits are a count of readers. */
  32 typedef struct arch_rwlock {
  33         unsigned int lock;
  34 } arch_rwlock_t;
  35
  36 #define __ARCH_RW_LOCK_UNLOCKED         { 0 }
  37
  38 #else
  39
  40 typedef struct arch_spinlock {
  41         /* Next ticket number to hand out. */
  42         int next_ticket;
  43         /* The ticket number that currently owns this lock. */
  44         int current_ticket;
  45 } arch_spinlock_t;
  46
  47 #define __ARCH_SPIN_LOCK_UNLOCKED       { 0, 0 }
  48
  49 /*
  50  * Byte 0 for tns (only the low bit is used), byte 1 for ticket-lock "next",
  51  * byte 2 for ticket-lock "current", byte 3 for reader count.
  52  */
  53 typedef struct arch_rwlock {
  54         unsigned int lock;
  55 } arch_rwlock_t;
  56
  57 #define __ARCH_RW_LOCK_UNLOCKED         { 0 }
  58
  59 #endif
  60 #endif /* _ASM_TILE_SPINLOCK_TYPES_H */