arch/ppc/syslib/dcr.S

   1 /*
   2  * arch/ppc/syslib/dcr.S
   3  *
   4  * "Indirect" DCR access
   5  *
   6  * Copyright (c) 2004 Eugene Surovegin <ebs@ebshome.net>
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under  the terms of  the GNU General Public License as published by the
  10  * Free Software Foundation;  either version 2 of the License, or (at your
  11  * option) any later version.
  12  */
  13
  14 #include <asm/ppc_asm.h>
  15 #include <asm/processor.h>
  16
  17 #define DCR_ACCESS_PROLOG(table) \
  18         rlwinm  r3,r3,4,18,27;   \
  19         lis     r5,table@h;      \
  20         ori     r5,r5,table@l;   \
  21         add     r3,r3,r5;        \
  22         mtctr   r3;              \
  23         bctr
  24
  25 _GLOBAL(__mfdcr)
  26         DCR_ACCESS_PROLOG(__mfdcr_table)
  27
  28 _GLOBAL(__mtdcr)
  29         DCR_ACCESS_PROLOG(__mtdcr_table)
  30
  31 __mfdcr_table:
  32         mfdcr  r3,0; blr
  33 __mtdcr_table:
  34         mtdcr  0,r4; blr
  35
  36 dcr     = 1
  37         .rept   1023
  38         mfdcr   r3,dcr; blr
  39         mtdcr   dcr,r4; blr
  40         dcr     = dcr + 1
  41         .endr