arch/powerpc/kernel/misc.S

   1 /*
   2  * This file contains miscellaneous low-level functions.
   3  *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
   4  *
   5  * Largely rewritten by Cort Dougan (cort@cs.nmt.edu)
   6  * and Paul Mackerras.
   7  *
   8  * PPC64 updates by Dave Engebretsen (engebret@us.ibm.com)
   9  *
  10  * setjmp/longjmp code by Paul Mackerras.
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License
  14  * as published by the Free Software Foundation; either version
  15  * 2 of the License, or (at your option) any later version.
  16  */
  17 #include <asm/ppc_asm.h>
  18 #include <asm/unistd.h>
  19 #include <asm/asm-compat.h>
  20 #include <asm/asm-offsets.h>
  21 #include <asm/export.h>
  22
  23         .text
  24
  25 /*
  26  * Returns (address we are running at) - (address we were linked at)
  27  * for use before the text and data are mapped to KERNELBASE.
  28  */
  29
  30 _GLOBAL(reloc_offset)
  31         mflr    r0
  32         bl      1f
  33 1:      mflr    r3
  34         PPC_LL  r4,(2f-1b)(r3)
  35         subf    r3,r4,r3
  36         mtlr    r0
  37         blr
  38
  39         .align  3
  40 2:      PPC_LONG 1b
  41
  42 /*
  43  * add_reloc_offset(x) returns x + reloc_offset().
  44  */
  45 _GLOBAL(add_reloc_offset)
  46         mflr    r0
  47         bl      1f
  48 1:      mflr    r5
  49         PPC_LL  r4,(2f-1b)(r5)
  50         subf    r5,r4,r5
  51         add     r3,r3,r5
  52         mtlr    r0
  53         blr
  54
  55         .align  3
  56 2:      PPC_LONG 1b
  57
  58 _GLOBAL(setjmp)
  59         mflr    r0
  60         PPC_STL r0,0(r3)
  61         PPC_STL r1,SZL(r3)
  62         PPC_STL r2,2*SZL(r3)
  63         mfcr    r0
  64         PPC_STL r0,3*SZL(r3)
  65         PPC_STL r13,4*SZL(r3)
  66         PPC_STL r14,5*SZL(r3)
  67         PPC_STL r15,6*SZL(r3)
  68         PPC_STL r16,7*SZL(r3)
  69         PPC_STL r17,8*SZL(r3)
  70         PPC_STL r18,9*SZL(r3)
  71         PPC_STL r19,10*SZL(r3)
  72         PPC_STL r20,11*SZL(r3)
  73         PPC_STL r21,12*SZL(r3)
  74         PPC_STL r22,13*SZL(r3)
  75         PPC_STL r23,14*SZL(r3)
  76         PPC_STL r24,15*SZL(r3)
  77         PPC_STL r25,16*SZL(r3)
  78         PPC_STL r26,17*SZL(r3)
  79         PPC_STL r27,18*SZL(r3)
  80         PPC_STL r28,19*SZL(r3)
  81         PPC_STL r29,20*SZL(r3)
  82         PPC_STL r30,21*SZL(r3)
  83         PPC_STL r31,22*SZL(r3)
  84         li      r3,0
  85         blr
  86
  87 _GLOBAL(longjmp)
  88         PPC_LCMPI r4,0
  89         bne     1f
  90         li      r4,1
  91 1:      PPC_LL  r13,4*SZL(r3)
  92         PPC_LL  r14,5*SZL(r3)
  93         PPC_LL  r15,6*SZL(r3)
  94         PPC_LL  r16,7*SZL(r3)
  95         PPC_LL  r17,8*SZL(r3)
  96         PPC_LL  r18,9*SZL(r3)
  97         PPC_LL  r19,10*SZL(r3)
  98         PPC_LL  r20,11*SZL(r3)
  99         PPC_LL  r21,12*SZL(r3)
 100         PPC_LL  r22,13*SZL(r3)
 101         PPC_LL  r23,14*SZL(r3)
 102         PPC_LL  r24,15*SZL(r3)
 103         PPC_LL  r25,16*SZL(r3)
 104         PPC_LL  r26,17*SZL(r3)
 105         PPC_LL  r27,18*SZL(r3)
 106         PPC_LL  r28,19*SZL(r3)
 107         PPC_LL  r29,20*SZL(r3)
 108         PPC_LL  r30,21*SZL(r3)
 109         PPC_LL  r31,22*SZL(r3)
 110         PPC_LL  r0,3*SZL(r3)
 111         mtcrf   0x38,r0
 112         PPC_LL  r0,0(r3)
 113         PPC_LL  r1,SZL(r3)
 114         PPC_LL  r2,2*SZL(r3)
 115         mtlr    r0
 116         mr      r3,r4
 117         blr
 118
 119 _GLOBAL(current_stack_pointer)
 120         PPC_LL  r3,0(r1)
 121         blr
 122 EXPORT_SYMBOL(current_stack_pointer)