examples/api/crt0.S

   1 /*
   2  * (C) Copyright 2007 Semihalf
   3  *
   4  * Written by: Rafal Jaworowski <raj@semihalf.com>
   5  *
   6  * SPDX-License-Identifier:     GPL-2.0+
   7  */
   8
   9 #if defined(CONFIG_PPC)
  10
  11         .text
  12         .globl _start
  13 _start:
  14         lis     %r11, search_hint@ha
  15         addi    %r11, %r11, search_hint@l
  16         stw     %r1, 0(%r11)
  17         b       main
  18
  19
  20         .globl syscall
  21 syscall:
  22         lis     %r11, syscall_ptr@ha
  23         addi    %r11, %r11, syscall_ptr@l
  24         lwz     %r11, 0(%r11)
  25         mtctr   %r11
  26         bctr
  27
  28 #elif defined(CONFIG_ARM)
  29
  30         .text
  31         .globl _start
  32 _start:
  33         ldr     ip, =search_hint
  34         str     sp, [ip]
  35         b       main
  36
  37
  38         .globl syscall
  39 syscall:
  40         ldr     ip, =syscall_ptr
  41         ldr     pc, [ip]
  42
  43 #elif defined(CONFIG_MIPS)
  44 #include <asm/asm.h>
  45         .text
  46         .globl __start
  47         .ent __start
  48 __start:
  49         PTR_S   $sp, search_hint
  50         b       main
  51         .end __start
  52
  53         .globl syscall
  54         .ent syscall
  55 syscall:
  56         PTR_S   $ra, return_addr
  57         PTR_L   $t9, syscall_ptr
  58         jalr    $t9
  59         nop
  60         PTR_L   $ra, return_addr
  61         jr      $ra
  62         nop
  63         .end syscall
  64
  65 return_addr:
  66         .align 8
  67         .long 0
  68 #else
  69 #error No support for this arch!
  70 #endif
  71
  72         .globl syscall_ptr
  73 syscall_ptr:
  74         .align  8
  75         .long   0
  76
  77         .globl search_hint
  78 search_hint:
  79         .long   0