kernel/tools/testing/selftests/powerpc/switch_endian/switch_endian_test.S

   1 #include "common.h"
   2
   3         .data
   4         .balign 8
   5 message:
   6         .ascii "success: switch_endian_test\n\0"
   7
   8         .section ".toc"
   9         .balign 8
  10 pattern:
  11         .llong 0x5555AAAA5555AAAA
  12
  13         .text
  14 FUNC_START(_start)
  15         /* Load the pattern */
  16         ld      r15, pattern@TOC(%r2)
  17
  18         /* Setup CR, only CR2-CR4 are maintained */
  19         lis     r3, 0x00FF
  20         ori     r3, r3, 0xF000
  21         mtcr    r3
  22
  23         /* Load the pattern slightly modified into the registers */
  24         mr      r3, r15
  25         addi    r4, r15, 4
  26
  27         addi    r5, r15, 32
  28         mtlr    r5
  29
  30         addi    r5, r15, 5
  31         addi    r6, r15, 6
  32         addi    r7, r15, 7
  33         addi    r8, r15, 8
  34
  35         /* r9 - r12 are clobbered */
  36
  37         addi    r13, r15, 13
  38         addi    r14, r15, 14
  39
  40         /* Skip r15 we're using it */
  41
  42         addi    r16, r15, 16
  43         addi    r17, r15, 17
  44         addi    r18, r15, 18
  45         addi    r19, r15, 19
  46         addi    r20, r15, 20
  47         addi    r21, r15, 21
  48         addi    r22, r15, 22
  49         addi    r23, r15, 23
  50         addi    r24, r15, 24
  51         addi    r25, r15, 25
  52         addi    r26, r15, 26
  53         addi    r27, r15, 27
  54         addi    r28, r15, 28
  55         addi    r29, r15, 29
  56         addi    r30, r15, 30
  57         addi    r31, r15, 31
  58
  59         /*
  60          * Call the syscall to switch endian.
  61          * It clobbers r9-r12, XER, CTR and CR0-1,5-7.
  62          */
  63         li r0, __NR_switch_endian
  64         sc
  65
  66 #include "check-reversed.S"
  67
  68         /* Flip back, r0 already has the switch syscall number */
  69         .long   0x02000044      /* sc */
  70
  71 #include "check.S"
  72
  73         li      r0, __NR_write
  74         li      r3, 1   /* stdout */
  75         ld      r4, message@got(%r2)
  76         li      r5, 28  /* strlen(message3) */
  77         sc
  78         li      r0, __NR_exit
  79         li      r3, 0
  80         sc
  81         b       .