arch/frv/lib/atomic-ops.S

   1 /* atomic-ops.S: kernel atomic operations
   2  *
   3  * For an explanation of how atomic ops work in this arch, see:
   4  *   Documentation/frv/atomic-ops.txt
   5  *
   6  * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
   7  * Written by David Howells (dhowells@redhat.com)
   8  *
   9  * This program is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU General Public License
  11  * as published by the Free Software Foundation; either version
  12  * 2 of the License, or (at your option) any later version.
  13  */
  14
  15 #include <asm/spr-regs.h>
  16
  17         .text
  18         .balign 4
  19
  20 ###############################################################################
  21 #
  22 # uint32_t __xchg_32(uint32_t i, uint32_t *v)
  23 #
  24 ###############################################################################
  25         .globl          __xchg_32
  26         .type           __xchg_32,@function
  27 __xchg_32:
  28         or.p            gr8,gr8,gr10
  29 0:
  30         orcc            gr0,gr0,gr0,icc3                /* set ICC3.Z */
  31         ckeq            icc3,cc7
  32         ld.p            @(gr9,gr0),gr8                  /* LD.P/ORCR must be atomic */
  33         orcr            cc7,cc7,cc3                     /* set CC3 to true */
  34         cst.p           gr10,@(gr9,gr0)         ,cc3,#1
  35         corcc           gr29,gr29,gr0           ,cc3,#1 /* clear ICC3.Z if store happens */
  36         beq             icc3,#0,0b
  37         bralr
  38
  39         .size           __xchg_32, .-__xchg_32
  40
  41 ###############################################################################
  42 #
  43 # uint32_t __cmpxchg_32(uint32_t *v, uint32_t test, uint32_t new)
  44 #
  45 ###############################################################################
  46         .globl          __cmpxchg_32
  47         .type           __cmpxchg_32,@function
  48 __cmpxchg_32:
  49         or.p            gr8,gr8,gr11
  50 0:
  51         orcc            gr0,gr0,gr0,icc3
  52         ckeq            icc3,cc7
  53         ld.p            @(gr11,gr0),gr8
  54         orcr            cc7,cc7,cc3
  55         subcc           gr8,gr9,gr7,icc0
  56         bnelr           icc0,#0
  57         cst.p           gr10,@(gr11,gr0)        ,cc3,#1
  58         corcc           gr29,gr29,gr0           ,cc3,#1
  59         beq             icc3,#0,0b
  60         bralr
  61
  62         .size           __cmpxchg_32, .-__cmpxchg_32