1/*	$OpenBSD: locore.S,v 1.18 1998/09/15 10:58:53 pefo Exp $	*/
2/*-
3 * Copyright (c) 1992, 1993
4 *	The Regents of the University of California.  All rights reserved.
5 *
6 * This code is derived from software contributed to Berkeley by
7 * Digital Equipment Corporation and Ralph Campbell.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 *    notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 * 4. Neither the name of the University nor the names of its contributors
18 *    may be used to endorse or promote products derived from this software
19 *    without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31 * SUCH DAMAGE.
32 *
33 * Copyright (C) 1989 Digital Equipment Corporation.
34 * Permission to use, copy, modify, and distribute this software and
35 * its documentation for any purpose and without fee is hereby granted,
36 * provided that the above copyright notice appears in all copies.
37 * Digital Equipment Corporation makes no representations about the
38 * suitability of this software for any purpose.  It is provided "as is"
39 * without express or implied warranty.
40 *
41 * from: Header: /sprite/src/kernel/mach/ds3100.md/RCS/loMem.s,
42 *	v 1.1 89/07/11 17:55:04 nelson Exp  SPRITE (DECWRL)
43 * from: Header: /sprite/src/kernel/mach/ds3100.md/RCS/machAsm.s,
44 *	v 9.2 90/01/29 18:00:39 shirriff Exp  SPRITE (DECWRL)
45 * from: Header: /sprite/src/kernel/vm/ds3100.md/vmPmaxAsm.s,
46 *	v 1.1 89/07/10 14:27:41 nelson Exp  SPRITE (DECWRL)
47 *
48 *	from: @(#)locore.s	8.5 (Berkeley) 1/4/94
49 *	JNPR: locore.S,v 1.6.2.1 2007/08/29 12:24:49 girish
50 * $FreeBSD$
51 */
52
53/*
54 * FREEBSD_DEVELOPERS_FIXME
55 * The start routine below was written for a multi-core CPU
56 * with each core being hyperthreaded. This serves as an example
57 * for a complex CPU architecture. For a different CPU complex
58 * please make necessary changes to read CPU-ID etc.
59 * A clean solution would be to have a different locore file for
60 * each CPU type.
61 */
62
63/*
64 *	Contains code that is the first executed at boot time plus
65 *	assembly language support routines.
66 */
67
68#include <machine/asm.h>
69#include <machine/cpu.h>
70#include <machine/cpuregs.h>
71#include <machine/regnum.h>
72
73#include "assym.s"
74
75	.data
76#ifdef YAMON
77GLOBAL(fenvp)
78	.space 4			# Assumes mips32?  Is that OK?
79#endif
80
81	.set noreorder
82
83	.text
84
85GLOBAL(btext)
86ASM_ENTRY(_start)
87VECTOR(_locore, unknown)
88	/* UNSAFE TO USE a0..a3, need to preserve the args from boot loader */
89	mtc0	zero, MIPS_COP_0_CAUSE	# Clear soft interrupts
90
91#if defined(CPU_CNMIPS)
92	/*
93	 * t1: Bits to set explicitly:
94	 *	Enable FPU
95	 */
96
97	/* Set these bits */
98        li	t1, (MIPS_SR_COP_0_BIT | MIPS_SR_PX | MIPS_SR_KX | MIPS_SR_UX | MIPS_SR_SX | MIPS_SR_BEV)
99
100	/* Reset these bits */
101        li	t0, ~(MIPS_SR_DE | MIPS_SR_SR | MIPS_SR_ERL | MIPS_SR_EXL | MIPS_SR_INT_IE | MIPS_SR_COP_2_BIT)
102#elif defined (CPU_RMI) || defined (CPU_NLM)
103	/* Set these bits */
104        li	t1, (MIPS_SR_COP_2_BIT | MIPS_SR_COP_0_BIT | MIPS_SR_KX | MIPS_SR_UX)
105
106	/* Reset these bits */
107        li	t0, ~(MIPS_SR_BEV | MIPS_SR_SR | MIPS_SR_INT_IE)
108#else
109	/*
110	 * t0: Bits to preserve if set:
111	 * 	Soft reset
112	 *	Boot exception vectors (firmware-provided)
113	 */
114	li	t0, (MIPS_SR_BEV | MIPS_SR_SR)
115	/*
116	 * t1: Bits to set explicitly:
117	 *	Enable FPU
118	 */
119	li	t1, MIPS_SR_COP_1_BIT
120#ifdef __mips_n64
121	or	t1, MIPS_SR_KX | MIPS_SR_SX | MIPS_SR_UX
122#endif
123#endif
124	/*
125	 * Read coprocessor 0 status register, clear bits not
126	 * preserved (namely, clearing interrupt bits), and set
127	 * bits we want to explicitly set.
128	 */
129	mfc0	t2, MIPS_COP_0_STATUS
130	and	t2, t0
131	or	t2, t1
132	mtc0	t2, MIPS_COP_0_STATUS
133	COP0_SYNC
134
135	/* Make sure KSEG0 is cached */
136	li	t0, MIPS_CCA_CACHED
137	mtc0	t0, MIPS_COP_0_CONFIG
138	COP0_SYNC
139
140	/*xxximp
141	 * now that we pass a0...a3 to the platform_init routine, do we need
142	 * to stash this stuff here?
143	 */
144#ifdef YAMON
145	/* Save YAMON boot environment pointer */
146	sw	a2, _C_LABEL(fenvp)
147#endif
148
149#if defined(CPU_CNMIPS) && defined(SMP)
150	.set push
151	.set mips32r2
152	rdhwr	t2, $0
153	beqz	t2, 1f
154	nop
155	j	octeon_ap_wait
156	nop
157	.set pop
1581:
159#endif
160
161	/*
162	 * Initialize stack and call machine startup.
163	 */
164	PTR_LA		sp, _C_LABEL(pcpu_space)
165	PTR_ADDU	sp, (PAGE_SIZE * 2) - CALLFRAME_SIZ
166
167	REG_S	zero, CALLFRAME_RA(sp)	# Zero out old ra for debugger
168	REG_S	zero, CALLFRAME_SP(sp)	# Zero out old fp for debugger
169
170	PTR_LA	gp, _C_LABEL(_gp)
171
172	/* Call the platform-specific startup code. */
173	jal	_C_LABEL(platform_start)
174	nop
175
176	PTR_LA	sp, _C_LABEL(thread0_st)
177	PTR_L	a0, TD_PCB(sp)
178	REG_LI	t0, ~7
179	and	a0, a0, t0
180	PTR_SUBU	sp, a0, CALLFRAME_SIZ
181
182	jal	_C_LABEL(mi_startup)		# mi_startup(frame)
183	sw	zero, CALLFRAME_SIZ - 8(sp)	# Zero out old fp for debugger
184
185	PANIC("Startup failed!")
186
187VECTOR_END(_locore)
188