Subversion Repositories openrisc_2011-10-31

/*
 *  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.
 *  On-Line Applications Research Corporation (OAR).
 *  Copyright assigned to U.S. Government, 1994.
 *
 *  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.
 *
 *  $Id: start.S,v 1.2 2001-09-27 12:01:12 chris Exp $
 */

#include "asm.h"

        BEGIN_CODE
        PUBLIC(start)

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

#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

        ! copy the vector table from rom to ram
        mov.l   vects_k,r0      ! vectab
        mov     #0,r1           ! address of boot vector table
        mov     #0,r2           ! number of bytes copied
        mov.w   vects_size,r3   ! size of entries in vectab
1:
        mov.l   @r1+,r4
        mov.l   r4,@r0
        add     #4,r0
        add     #1,r2
        cmp/hi  r3,r2
        bf      1b

#ifndef STANDALONE_EVB
        ! overlay monitor vectors onto RTEMS table template
        ! code adapted  from Hitachi EDK7045F User Manual: "Copyvect.s"
        mova    vects_k,r0
        mov.l   @r0, r1 ! Shadow vect tbl addr
        stc             vbr, r2 ! Original vect tbl addr
        and             #0, r0 
        mov             r0, r4  ! 0 in r4 and r0

!trapa #32
        or              #0x80, r0
        mov.l   @(r0,r2), r3
        mov.l   r3, @(r0, r1)
        mov             r4, r0

!cpu addr err
        or              #0x24, r0
        mov.l   @(r0, r2), r3
        mov.l   r3, @(r0, r1)
        mov             r4, r0

!ill slot
        or              #0x18, r0
        mov.l   @(r0, r2), r3
        mov.l   r3, @(r0, r1)
        mov             r4, r0

!ill inst
        or              #0x10, r0
        mov.l   @(r0, r2), r3
        mov.l   r3, @(r0, r1)
        mov             r4, r0

!nmi
        or              #0x2c, r0
        mov.l   @(r0, r2), r3
        mov.l   r3, @(r0, r1)
        mov             r4, r0

!User brk
        or              #0x30, r0
        mov.l   @(r0, r2), r3
        mov.l   r3, @(r0, r1)
        mov             r4, r0

!sci0 err
        or              #0x80, r0
        rotl    r0
        rotl    r0
        mov.l   @(r0, r2), r3
        mov.l   r3, @(r0, r1)
        mov             r4, r0
!sci rx
        or              #0x81, r0
        rotl    r0
        rotl    r0
        mov.l   @(r0, r2), r3
        mov.l   r3, @(r0, r1)

        stc     vbr,r3          ! capture copy of monitor vbr
        mov.l   vbrtemp_k,r0
        mov.l   r3, @r0
        mov.l   vects_k,r0      ! point vbr to vectab
        ldc     r0,vbr
#endif  ! STANDALONE_EVB

        ! 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

        mov.l   vbrtemp_k,r0    ! restore original vbr
        mov.l   @r0,r3
        ldc     r3, vbr
        trapa   #13             ! UBR capture by monitor
        nop             !debug dead-slot target

        END_CODE

        .align 2
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 */
vbrtemp_k:
        .long   SYM(vbrtemp)
vects_k:
        .long   SYM(vectab)
vects_size:
        .word   255

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

#ifdef __ELF__
        .section .bss,"aw"
#else
        .section .bss
#endif
SYM(vbrtemp):
        .long   0x0