arch/powerpc/xmon/spr_access.S

   1 #include <asm/ppc_asm.h>
   2
   3 /* unsigned long xmon_mfspr(sprn, default_value) */
   4 _GLOBAL(xmon_mfspr)
   5         PPC_LL  r5, .Lmfspr_table@got(r2)
   6         b       xmon_mxspr
   7
   8 /* void xmon_mtspr(sprn, new_value) */
   9 _GLOBAL(xmon_mtspr)
  10         PPC_LL  r5, .Lmtspr_table@got(r2)
  11         b       xmon_mxspr
  12
  13 /*
  14  * r3 = sprn
  15  * r4 = default or new value
  16  * r5 = table base
  17  */
  18 xmon_mxspr:
  19         /*
  20          * To index into the table of mxsprs we need:
  21          *  i = (sprn & 0x3ff) * 8
  22          * or using rwlinm:
  23          *  i = (sprn << 3) & (0x3ff << 3)
  24          */
  25         rlwinm  r3, r3, 3, 0x3ff << 3
  26         add     r5, r5, r3
  27         mtctr   r5
  28         mr      r3, r4 /* put default_value in r3 for mfspr */
  29         bctr
  30
  31 .Lmfspr_table:
  32         spr = 0
  33         .rept   1024
  34         mfspr   r3, spr
  35         blr
  36         spr = spr + 1
  37         .endr
  38
  39 .Lmtspr_table:
  40         spr = 0
  41         .rept   1024
  42         mtspr   spr, r4
  43         blr
  44         spr = spr + 1
  45         .endr