NetBSD/sys/arch/sparc/stand/srt0.S

198 lines
4.1 KiB
ArmAsm

/* $NetBSD: srt0.S,v 1.7 1996/10/18 01:36:16 thorpej Exp $ */
/*
* Copyright (c) 1994 Paul Kranenburg
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Paul Kranenburg.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <machine/param.h>
#include <machine/psl.h>
#define CCFSZ 96
.file "str0.s"
.data
.global _cputyp, _nbpg, _pgofset, _pgshift
_cputyp:
.word 1
_nbpg:
.word 1
_pgofset:
.word 1
_pgshift:
.word 1
.text
.globl start
start:
/*
* Set up a stack.
*/
set start, %o1
save %o1, -CCFSZ, %sp
/*
* Relocate.
*/
1: call 2f
nop
2: add %o7, (start-1b), %l0
set start, %l1
set _end, %o0
sub %o0, %l1, %l2 ! length
3: ld [%l0], %o0
add %l0, 4, %l0
st %o0, [%l1]
subcc %l2, 4, %l2
bg 3b
add %l1, 4, %l1
set 4f, %g1
jmp %g1
nop
4:
#ifdef notyet
/*
* Enable traps
*/
wr %g0, 0, %wim ! make sure we can set psr
nop; nop; nop
wr %g0, PSR_S|PSR_PS|PSR_PIL, %psr ! set initial psr
nop; nop; nop
wr %g0, 2, %wim ! set initial %wim (w1 invalid)
rd %psr, %l0
wr %l0, PSR_ET, %psr
nop; nop; nop
#endif
/*
* Clear BSS
*/
set _edata, %o0 ! bzero(edata, end - edata)
set _end, %o1
call _bzero
sub %o1, %o0, %o1
/*
* Enable interrupts, but only above level 11. This enables "L1-A",
* but avoids spurious interrupt bites from most other devices.
*/
rd %psr, %o0
andn %o0, PSR_PIL, %o0
wr %o0, 0xb00, %psr ! (11 << 8)
nop; nop; nop
/*
* Set CPU type that we are running on.
*/
sethi %hi(_cputyp), %o0
set 0x4000, %g7
cmp %i0, %g7
beq 5f
nop
/*
* Save address of PROM vector (passed in %i0).
*/
sethi %hi(_promvec), %o1
st %i0, [%o1 + %lo(_promvec)]
mov CPU_SUN4C, %g4
mov SUN4CM_PGSHIFT, %g5
b,a 6f
5:
mov CPU_SUN4, %g4
mov SUN4_PGSHIFT, %g5
6:
st %g4, [%o0 + %lo(_cputyp)]
sethi %hi(_pgshift), %o0 ! pgshift = log2(nbpg)
st %g5, [%o0 + %lo(_pgshift)]
mov 1, %o0 ! nbpg = 1 << pgshift
sll %o0, %g5, %g5
sethi %hi(_nbpg), %o0 ! nbpg = bytes in a page
st %g5, [%o0 + %lo(_nbpg)]
sub %g5, 1, %g5
sethi %hi(_pgofset), %o0 ! page offset = bytes in a page - 1
st %g5, [%o0 + %lo(_pgofset)]
call _main
mov %i0, %o0
ret
restore
#ifdef TIGHT
/*
* XXX - Space saving .div & .rem routines (small & non-negative numbres only)
*/
.align 4
.global .div, .udiv
! int n = 0; while (a >= b) { a -= b; n++; }; return n;
.div:
.udiv:
cmp %o0, %o1
bl 2f
mov 0, %o5
1:
sub %o0, %o1, %o0
cmp %o0, %o1
bge 1b
add %o5, 1, %o5
2:
retl
mov %o5, %o0
.align 4
.global .rem, .urem
! while (a>=b) a -= b; return a;
.rem:
.urem:
cmp %o0, %o1
bl 2f
nop
sub %o0, %o1, %o0
1:
cmp %o0, %o1
bge,a 1b
sub %o0, %o1, %o0
2:
retl
nop
#endif /* TIGHT */