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

241 lines
5.4 KiB
ArmAsm

/* $NetBSD: srt0.S,v 1.7 2001/11/21 21:38:00 uwe Exp $ */
/*-
* Copyright (c) 1999 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Paul Kranenburg.
*
* 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 the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``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 FOUNDATION OR CONTRIBUTORS
* 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.
*/
#define _LOCORE /* XXX - fix Makefile */
#include <machine/param.h>
#include <machine/asm.h>
#include <machine/psl.h>
#define CCFSZ 96
.file "str0.s"
.comm _C_LABEL(romp), 4
.comm _C_LABEL(cputyp), 4
.comm _C_LABEL(nbpg), 4
.comm _C_LABEL(pgofset), 4
.comm _C_LABEL(pgshift), 4
.text
.globl start
start:
/*
* Set up a stack.
*/
set start, %o1
save %o1, -CCFSZ, %sp
/*
* Find which address we are at.
*/
1: call 2f
sethi %hi(1b), %l0
2: or %l0, %lo(1b), %l0
cmp %l0, %o7 ! %o7 contains actual address of 1b
beq 4f ! already there, no need to relocate
nop
/*
* Relocate.
*/
add %o7, (start-1b), %l0
set start, %l1
set _edata, %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
/*
* Jump to our relocated self.
*/
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
/* note: bzero() expanded inline for compactness */
subcc %o1, %o0, %o1
bz 2f ! in case there is no BSS
srl %o1, 2, %o1 ! assume _edata & _end are aligned
1:
st %g0, [%o0] ! while (n--)
subcc %o1, 1, %o1 ! *p = 0; etc..
bnz 1b
add %o0, 4, %o0
2:
/*
* 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(_C_LABEL(cputyp)), %o0
set 0x4000, %g7
cmp %i0, %g7
beq is_sun4
nop
mov CPU_SUN4C, %g4
mov SUN4CM_PGSHIFT, %g5
/*
* OpenProm machines pass PROM vector in %o0 (%i0 after save)
* OpenFirm machines pass OF entry in %o3 (%i3 after save)
*/
cmp %i0, 0
be is_openfirm
nop
! save address of PROM vector
sethi %hi(_C_LABEL(romp)), %o1
st %i0, [%o1 + %lo(_C_LABEL(romp))]
b,a is_sun4cm
is_openfirm:
! save address of OpenFirmware client interface handler
sethi %hi(_C_LABEL(romp)), %o1
st %i3, [%o1 + %lo(_C_LABEL(romp))]
b,a is_sun4cm
is_sun4:
mov CPU_SUN4, %g4
mov SUN4_PGSHIFT, %g5
is_sun4cm:
st %g4, [%o0 + %lo(_C_LABEL(cputyp))]
sethi %hi(_C_LABEL(pgshift)), %o0 ! pgshift = log2(nbpg)
st %g5, [%o0 + %lo(_C_LABEL(pgshift))]
mov 1, %o0 ! nbpg = 1 << pgshift
sll %o0, %g5, %g5
sethi %hi(_C_LABEL(nbpg)), %o0 ! nbpg = bytes in a page
st %g5, [%o0 + %lo(_C_LABEL(nbpg))]
sub %g5, 1, %g5
sethi %hi(_C_LABEL(pgofset)), %o0 ! page offset = nbpg - 1
st %g5, [%o0 + %lo(_C_LABEL(pgofset))]
call _C_LABEL(main)
mov %i0, %o0
ret
restore
/*
* NO-OP place holder function.
*/
ENTRY(sparc_noop)
retl
nop
#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 */