Subversion Repositories openrisc_2011-10-31

/* Startup code for M68HC11/M68HC12.

 * Copyright (C) 1999, 2000, 2001, 2002 Stephane Carrez (stcarrez@nerim.fr)

 *

 * 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.

 */

;-----------------------------------------

; startup code

;-----------------------------------------

        .file   "crt0.s"

;;

;;

;; The linker concatenate the .install* sections in the following order:

;;

;; .install0    Setup the stack pointer

;; .install1    Place holder for applications

;; .install2    Optional installation of data section in memory

;; .install3    Place holder for applications

;; .install4    Invokes the main

;;

        .sect   .install0,"ax",@progbits

        .globl _start

_start:

;;

;; At this step, the stack is not initialized and interrupts are masked.

;; Applications only have 64 cycles to initialize some registers.

;;

;; To have a generic/configurable startup, initialize the stack to

;; the end of some memory region.  The _stack symbol is defined by

;; the linker.

;;

        lds     #_stack

        .sect   .install2,"ax",@progbits

;;

;; Call a specific initialization operation.  The default is empty.

;; It can be overriden by applications.  It is intended to initialize

;; the 68hc11 registers.  Function prototype is:

;;

;;      int __premain(void);

;;

        jsr     __premain

;;

;;

;;

        .sect   .install4,"ax",@progbits

        jsr     main

fatal:

        jsr     exit

        bra fatal

;-----------------------------------------

; end startup code

;-----------------------------------------

;; Force loading of data section mapping and bss clear

        .globl  __map_data_section

        .globl  __init_bss_section