include/urcu/arch/ppc.h

   1 // SPDX-FileCopyrightText: 2009 Paul E. McKenney, IBM Corporation.
   2 // SPDX-FileCopyrightText: 2009 Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
   3 //
   4 // SPDX-License-Identifier: LGPL-2.1-or-later
   5
   6 #ifndef _URCU_ARCH_PPC_H
   7 #define _URCU_ARCH_PPC_H
   8
   9 /*
  10  * arch_ppc.h: trivial definitions for the powerpc architecture.
  11  */
  12
  13 #include <urcu/compiler.h>
  14 #include <urcu/config.h>
  15 #include <urcu/syscall-compat.h>
  16 #include <stdint.h>
  17
  18 #ifdef __cplusplus
  19 extern "C" {
  20 #endif
  21
  22 /* Include size of POWER5+ L3 cache lines: 256 bytes */
  23 #define CAA_CACHE_LINE_SIZE     256
  24
  25 #ifdef __NO_LWSYNC__
  26 #define LWSYNC_OPCODE   "sync\n"
  27 #else
  28 #define LWSYNC_OPCODE   "lwsync\n"
  29 #endif
  30
  31 /*
  32  * Use sync for all cmm_mb/rmb/wmb barriers because lwsync does not
  33  * preserve ordering of cacheable vs. non-cacheable accesses, so it
  34  * should not be used to order with respect to MMIO operations.  An
  35  * eieio+lwsync pair is also not enough for cmm_rmb, because it will
  36  * order cacheable and non-cacheable memory operations separately---i.e.
  37  * not the latter against the former.
  38  */
  39 #define cmm_mb()         __asm__ __volatile__ ("sync":::"memory")
  40
  41 /*
  42  * lwsync orders loads in cacheable memory with respect to other loads,
  43  * and stores in cacheable memory with respect to other stores.
  44  * Therefore, use it for barriers ordering accesses to cacheable memory
  45  * only.
  46  */
  47 #define cmm_smp_rmb()    __asm__ __volatile__ (LWSYNC_OPCODE:::"memory")
  48 #define cmm_smp_wmb()    __asm__ __volatile__ (LWSYNC_OPCODE:::"memory")
  49
  50 #define mftbl()                                         \
  51         __extension__                                   \
  52         ({                                              \
  53                 unsigned long rval;                     \
  54                 __asm__ __volatile__ ("mftbl %0" : "=r" (rval));        \
  55                 rval;                                   \
  56         })
  57
  58 #define mftbu()                                         \
  59         __extension__                                   \
  60         ({                                              \
  61                 unsigned long rval;                     \
  62                 __asm__ __volatile__ ("mftbu %0" : "=r" (rval));        \
  63                 rval;                                   \
  64         })
  65
  66 #define mftb()                                          \
  67         __extension__                                   \
  68         ({                                              \
  69                 unsigned long long rval;                \
  70                 __asm__ __volatile__ ("mftb %0" : "=r" (rval));         \
  71                 rval;                                   \
  72         })
  73
  74 #define HAS_CAA_GET_CYCLES
  75
  76 typedef uint64_t caa_cycles_t;
  77
  78 #ifdef __powerpc64__
  79 static inline caa_cycles_t caa_get_cycles(void)
  80 {
  81         return (caa_cycles_t) mftb();
  82 }
  83 #else
  84 static inline caa_cycles_t caa_get_cycles(void)
  85 {
  86         unsigned long h, l;
  87
  88         for (;;) {
  89                 h = mftbu();
  90                 cmm_barrier();
  91                 l = mftbl();
  92                 cmm_barrier();
  93                 if (mftbu() == h)
  94                         return (((caa_cycles_t) h) << 32) + l;
  95         }
  96 }
  97 #endif
  98
  99 /*
 100  * On Linux, define the membarrier system call number if not yet available in
 101  * the system headers.
 102  */
 103 #if (defined(__linux__) && !defined(__NR_membarrier))
 104 #define __NR_membarrier         365
 105 #endif
 106
 107 #ifdef __cplusplus
 108 }
 109 #endif
 110
 111 #include <urcu/arch/generic.h>
 112
 113 #endif /* _URCU_ARCH_PPC_H */