Retro68/gcc/libgloss/m68hc11/crt0.S

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/* 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