arch/powerpc/boot/virtex405-head.S

   1 #include "ppc_asm.h"
   2
   3         .text
   4         .global _zimage_start
   5 _zimage_start:
   6
   7         /* PPC errata 213: needed by Virtex-4 FX */
   8         mfccr0  0
   9         oris    0,0,0x50000000@h
  10         mtccr0  0
  11
  12         /*
  13          * Invalidate the data cache if the data cache is turned off.
  14          * - The 405 core does not invalidate the data cache on power-up
  15          *   or reset but does turn off the data cache. We cannot assume
  16          *   that the cache contents are valid.
  17          * - If the data cache is turned on this must have been done by
  18          *   a bootloader and we assume that the cache contents are
  19          *   valid.
  20          */
  21         mfdccr  r9
  22         cmplwi  r9,0
  23         bne     2f
  24         lis     r9,0
  25         li      r8,256
  26         mtctr   r8
  27 1:      dccci   r0,r9
  28         addi    r9,r9,0x20
  29         bdnz    1b
  30 2:      b       _zimage_start_lib