ecosflash/flash.S

   1 /*
   2         Jump table for flash driver
   3
   4         Registers in ARM callling convention is to place args in registers
   5         starting at r0.
   6
   7         So for:
   8
   9         void foo(int a, int b, int c).
  10
  11         a=r0
  12         b=r1
  13         c=r2
  14
  15
  16 */
  17         .global _stack_base
  18         .global _stack_start
  19         .global _workarea
  20         .global _start
  21         .global _start_bss_clear
  22 _start:
  23         // offset=0
  24         // int erase(void *address, int len)
  25         ldr     sp,=_stack_start
  26         bl erase
  27         nop // Stop CPU here using hw breakpoint
  28
  29         // offset=0xc
  30         // int program(void *buffer, void *address, int len)
  31         ldr     sp,=_stack_start
  32         bl program
  33         nop // Stop CPU here using hw breakpoint
  34
  35         // offset=0x18
  36         ldr     r0,=_workarea
  37         nop // Stop CPU here using hw breakpoint
  38
  39         // offset=0x20
  40         // int init() - returns error message if the flash chip can't be detected
  41         ldr     sp,=_stack_start
  42         bl init
  43         nop // Stop CPU here using hw breakpoint
  44
  45     .section ".bss"
  46     .balign 4
  47 _stack_base:
  48         .rept 4096
  49         .byte 0
  50         .endr
  51 _stack_start:
  52     .balign 4
  53 _workarea:
  54         .rept 8192
  55         .byte 0
  56         .endr
  57         // NB!!! we clear bss while the stack is in use, so we start BSS clearing here !!! :-)
  58 _start_bss_clear: