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[/] [openrisc/] [trunk/] [rtos/] [rtems/] [c/] [src/] [lib/] [libbsp/] [hppa1.1/] [simhppa/] [start/] [start.S] - Rev 173
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/*
* crt0.S -- startup file for hppa on RTEMS
*
* $Id: start.S,v 1.2 2001-09-27 11:59:45 chris Exp $
*/
.COPYRIGHT "crt0.S for hppa"
.DATA
_progname .STRINGZ "simhppa"
_crt0_argv .WORD _progname, 0
/*
* Set up the standard spaces (sections) These definitions come
* from /lib/pcc_prefix.s.
*/
.TEXT
/*
* stuff we need that is defined elsewhere.
*/
.IMPORT boot_card, CODE
.IMPORT _bss_start, DATA
.IMPORT _bss_end, DATA
.IMPORT environ, DATA
/*
* start -- set things up so the application will run.
*
*/
.PROC
.CALLINFO SAVE_SP, FRAME=48
.EXPORT $START$,ENTRY
.EXPORT start,ENTRY
$START$
start:
/*
* Get a stack
*/
ldil L%crt_stack+48,%r30
ldo R%crt_stack+48(%r30),%r30
/*
* we need to set %r27 (global data pointer) here
*/
ldil L%$global$,%r27
ldo R%$global$(%r27),%r27
/*
* zerobss -- zero out the bss section
* XXX We don't do this since simulator and boot rom will do this for us.
*/
#if 0
; load the start of bss
ldil L%_bss_start,%r4
ldo R%_bss_start(%r4),%r4
; load the end of bss
ldil L%_bss_end,%r5
ldo R%_bss_end(%r5),%r5
bssloop
addi -1,%r5,%r5 ; decrement _bss_end
stb %r0,0(0,%r5) ; we do this by bytes for now even
; though it is slower, it is safer
combf,= %r4,%r5, bssloop
nop
#endif
ldi 1,%ret0
/*
* Call the "boot_card" routine from the application to get it going.
* We call it as boot_card(1, argv, 0)
*/
copy %r0, %r24
ldil L%_crt0_argv,%r25
ldo R%_crt0_argv(%r25),%r25
bl boot_card,%r2
ldo 1(%r0), %r26
.PROCEND
/*
* _exit -- Exit from the application. Normally we cause a user trap
* to return to the ROM monitor for another run, but with
* this monitor we can not. Still, "C" wants this symbol, it
* should be here. Jumping to 0xF0000004 jumps back into the
* firmware, while writing a 5 to 0xFFFE0030 causes a reset.
*/
_exit_fallthru
.PROC
.CALLINFO
.ENTRY
;; This just causes a breakpoint exception
break 0x0,0x0
bv,n (%rp)
nop
.EXIT
.PROCEND
/*
* _sr4export -- support for called functions. (mostly for GDB)
*/
.EXPORT _sr4export, ENTRY
_sr4export:
.PROC
.CALLINFO
.ENTRY
ble 0(%sr4,%r22)
copy %r31,%rp
ldw -18(%sr0,%sp),%rp
ldsid (%sr0,%rp),%r1
mtsp %r1,%sr0
be,n 0(%sr0,%rp)
nop
.EXIT
.PROCEND
.subspa $UNWIND_START$,QUAD=0,ALIGN=8,ACCESS=0x2c,SORT=56
.export $UNWIND_START
$UNWIND_START
.subspa $UNWIND$,QUAD=0,ALIGN=8,ACCESS=0x2c,SORT=64
.subspa $UNWIND_END$,QUAD=0,ALIGN=8,ACCESS=0x2c,SORT=72
.export $UNWIND_END
$UNWIND_END
.subspa $RECOVER_START$,QUAD=0,ALIGN=4,ACCESS=0x2c,SORT=73
.export $RECOVER_START
$RECOVER_START
.subspa $RECOVER$,QUAD=0,ALIGN=4,ACCESS=0x2c,SORT=80
.subspa $RECOVER_END$,QUAD=0,ALIGN=4,ACCESS=0x2c,SORT=88
.export $RECOVER_END
$RECOVER_END
/*
* Here we set up the standard date sub spaces.
*
* Set up some room for a stack. We just grab a chunk of memory.
* We also setup some space for the global variable space, which
* must be done using the reserved name "$global$" so "C" code
* can find it. The stack grows towards the higher addresses.
*/
.subspa $DATA$,QUAD=1,ALIGN=8,ACCESS=0x1f,SORT=16
.subspa $SHORTDATA$,QUAD=1,ALIGN=8,ACCESS=0x1f,SORT=24
.subspa $GLOBAL$,QUAD=1,ALIGN=8,ACCESS=0x1f,SORT=40
.export $global$
$global$
.subspa $SHORTBSS$,QUAD=1,ALIGN=8,ACCESS=0x1f,SORT=80,ZERO
.subspa $BSS$,QUAD=1,ALIGN=8,ACCESS=0x1f,SORT=82,ZERO
.subspa $STACK$,QUAD=1,ALIGN=8,ACCESS=0x1f,SORT=88,ZERO
.export crt_stack
crt_stack
.comm 0x1000
.end