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/*
 * start.S -- Initialization code for SH4 simulator BSP
 *
 * Copyright (C) 2001 OKTET Ltd., St.-Petersburg, Russia
 * Author: Victor V. Vengerov <vvv@oktet.ru>
 *
 * Based on work:
 *  Authors: Ralf Corsepius (corsepiu@faw.uni-ulm.de) and
 *           Bernd Becker (becker@faw.uni-ulm.de)
 *
 *  COPYRIGHT (c) 1997-1998, FAW Ulm, Germany
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
 *
 *  Modified to reflect Hitachi EDK SH7045F:
 *  John M. Mills (jmills@tga.com)
 *  TGA Technologies, Inc.
 *  100 Pinnacle Way, Suite 140
 *  Norcross, GA 30071 U.S.A.
 *  
 *
 *  This modified file may be copied and distributed in accordance
 *  the above-referenced license. It is provided for critique and
 *  developmental purposes without any warranty nor representation
 *  by the authors or by TGA Technologies.
 *
 *  COPYRIGHT (c) 1999-2001.
 *  On-Line Applications Research Corporation (OAR).
 *
 *  The license and distribution terms for this file may be
 *  found in the file LICENSE in this distribution or at
 *  http://www.OARcorp.com/rtems/license.html.
 *
 *  start.S,v 1.1 2001/10/11 21:04:35 joel Exp
 */

#include "asm.h"
#include "rtems/score/sh4_regs.h"

        BEGIN_CODE
        PUBLIC(start)

SYM (start):
        ! install the stack pointer
        mov.l   stack_k,r15

        mov.l   initial_sr_k,r0
        ldc     r0,ssr
        ldc     r0,sr

        ! Set up VBR register
        mov.l   _vbr_base_k,r0
        ldc     r0,vbr


#ifdef  START_HW_INIT   /* from $RTEMS_BSP.cfg */
        ! Initialize minimal hardware
        mov.l   hw_init_k, r0
        jsr @r0
        nop             !dead slot
#endif /* START_HW_INIT */

        ! zero out bss
        mov.l   edata_k,r0
        mov.l   end_k,r1
        mov     #0,r2
0:
        mov.l   r2,@r0
        add     #4,r0
        cmp/ge  r0,r1
        bt      0b

        ! initialise fpscr for gcc
        mov.l set_fpscr_k, r1
        jsr @r1
        nop

        ! Set FPSCR register
        mov.l   initial_fpscr_k,r0
        lds     r0,fpscr

        ! call the mainline     
        mov #0,r4               ! argc
        mov.l main_k,r0
        jsr @r0
        mov #0,r5               ! argv - can place in dead slot

        ! call exit
        mov     r0,r4
        mov.l   exit_k,r0
        jsr     @r0
        or      r0,r0

        ! stop the simulator
        trapa   #2
        nop

        .global ___trap34
___trap34:
        trapa   #34
!       tst     r1,r1   ! r1 is errno
!       bt      ret
!       mov.l   perrno,r2
!       mov.l   r1,@r2
!ret:
        rts
        nop
        
!       .align  2
!perrno:
!       .long   _errno


        END_CODE

        .align 2
set_fpscr_k:
    .long   ___set_fpscr
_vbr_base_k:
        .long   SYM(_vbr_base)

stack_k:
        .long   SYM(stack)      
edata_k:
        .long   SYM(edata)
end_k:
        .long   SYM(end)
main_k:
        .long   SYM(boot_card)
exit_k:
        .long   SYM(exit)

#ifdef  START_HW_INIT   /* from $RTEMS_BSP.cfg */
hw_init_k:
        .long   SYM(early_hw_init)
#endif /* START_HW_INIT */

vects_k:
        .long   SYM(vectab)
vects_size:
        .word   255

    .align 2
initial_sr_k:
        .long   SH4_SR_MD | SH4_SR_RB | SH4_SR_IMASK
initial_fpscr_k:
#ifdef __SH4__
        .long   SH4_FPSCR_DN | SH4_FPSCR_PR | SH4_FPSCR_RM
#else
        .long   SH4_FPSCR_DN | SH4_FPSCR_RM
#endif

#ifdef __ELF__
        .section .stack,"aw"
#else
        .section .stack
#endif
SYM(stack):
        .long   0xdeaddead

#ifdef __ELF__
        .section .bss,"aw"
#else
        .section .bss
#endif

        .global __sh4sim_dummy_register
__sh4sim_dummy_register:
        .long   0