.section ".text.boot"

  .global _start

  _start:
      mrc p15, #0, r1, c0, c0, #5
      and r1, r1, #3
      cmp r1, #0
      bne halt

      mov sp, #0x8000

      ldr r4, =__bss_start
      ldr r9, =__bss_end
      mov r5, #0
      mov r6, #0
      mov r7, #0
      mov r8, #0
      b       2f

  1:
      stmia r4!, {r5-r8}

  2:
      cmp r4, r9
      blo 1b

      ldr r3, =main
      blx r3

  halt:
      wfe
      b halt