Subversion Repositories openrisc_2011-10-31

##==============================================================================

##

##      crt0-eval.S

##

##      MN10300 Series Evaluation Board C startup code

##

##==============================================================================

######COPYRIGHTBEGIN####

##

## Copyright (c) 1995, 1996, 1997, 1998 Cygnus Solutions

##

## The authors hereby grant permission to use, copy, modify, distribute,

## and license this software and its documentation for any purpose, provided

## that existing copyright notices are retained in all copies and that this

## notice is included verbatim in any distributions. No written agreement,

## license, or royalty fee is required for any of the authorized uses.

## Modifications to this software may be copyrighted by their authors

## and need not follow the licensing terms described here, provided that

## the new terms are clearly indicated on the first page of each file where

## they apply.

##

######COPYRIGHTEND####

##------------------------------------------------------------------------------

        .file   "crt0-eval.S"

##------------------------------------------------------------------------------

## Startup code

        .equ    DRAM_TOP,0x48100000

        .text

        .globl  __start

__start:

        # Set up stack.  Leave 4K at top for use by Cygmon.

        mov     DRAM_TOP - 0x1000,a0

        sub     8,a0

        mov     a0,sp

        # Clear BSS

        mov     __bss_start,a0

        mov     _end,a1

        cmp     a0,a1

        beq     8f

        clr     d0

1:

        movbu   d0,(a0)

        inc     a0

        cmp     a0,a1

        bne     1b

8:

        # Call constructors

        .extern ___main

        call    ___main,[],0

        # Call main

        clr     d0

        clr     d1

        mov     d0,(4,sp)

9:

        or      0x0800,psw      # Enable interrupts

        .extern _main

        call    _main,[],0

        .extern __exit

        call    __exit,[],0

#       bra     9b              # Loop if we return

##------------------------------------------------------------------------------

## end of crt0-eval.S