bootrom/flash-reset.s

   1 @-----------------------------------------------------------------------------
   2 @ This code is licensed to you under the terms of the GNU GPL, version 2 or,
   3 @ at your option, any later version. See the LICENSE.txt file for the text of
   4 @ the license.
   5 @-----------------------------------------------------------------------------
   6 @ Reset vector for running from FLASH
   7 @-----------------------------------------------------------------------------
   8
   9 .section .startup,"ax"
  10
  11 .arm
  12
  13 .global flashstart
  14 flashstart:
  15     b   reset
  16     b   undefined_instruction
  17     b   software_interrupt
  18     b   prefetch_abort
  19     b   data_abort
  20     b   . @reserved
  21     ldr pc, [pc,#-0xF20]    @ IRQ - read the AIC
  22     b   fiq
  23
  24 reset:
  25     ldr sp, =_stack_end     @ initialize stack pointer to top of RAM
  26
  27     @ copy bootloader to RAM (in case the user re-flashes the bootloader)
  28     ldr r0, =__bootphase2_src_start__
  29     ldr r1, =__bootphase2_start__
  30     ldr r2, =__bootphase2_end__
  31 1:
  32     ldr r3, [r0], #4
  33     str r3, [r1], #4
  34     cmp r1, r2
  35     blo 1b
  36
  37     ldr r3, =ram_start      @ start address of RAM bootloader
  38     bx  r3                  @ jump to it
  39
  40     .ltorg
  41
  42 undefined_instruction:
  43     b   .
  44 software_interrupt:
  45     b   .
  46 prefetch_abort:
  47     b   .
  48 data_abort:
  49     b   .
  50 fiq:
  51     b   .