locore2.c revision 1.20
1/*	$NetBSD: locore2.c,v 1.20 1998/06/12 20:07:50 gwr Exp $	*/
2
3/*-
4 * Copyright (c) 1996 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Gordon W. Ross and Jeremy Cooper.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. All advertising materials mentioning features or use of this software
19 *    must display the following acknowledgement:
20 *        This product includes software developed by the NetBSD
21 *        Foundation, Inc. and its contributors.
22 * 4. Neither the name of The NetBSD Foundation nor the names of its
23 *    contributors may be used to endorse or promote products derived
24 *    from this software without specific prior written permission.
25 *
26 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
27 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
28 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
29 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
30 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
31 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
32 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
33 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
34 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
35 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
36 * POSSIBILITY OF SUCH DAMAGE.
37 */
38
39#include <sys/param.h>
40#include <sys/systm.h>
41#include <sys/proc.h>
42#include <sys/reboot.h>
43#include <sys/user.h>
44#include <sys/exec_aout.h>
45
46#include <vm/vm.h>
47
48#include <machine/cpu.h>
49#include <machine/db_machdep.h>
50#include <machine/dvma.h>
51#include <machine/idprom.h>
52#include <machine/leds.h>
53#include <machine/mon.h>
54#include <machine/pmap.h>
55#include <machine/pte.h>
56
57#include <sun3/sun3/interreg.h>
58#include <sun3/sun3/machdep.h>
59#include <sun3/sun3/vector.h>
60
61/* This is defined in locore.s */
62extern char kernel_text[];
63
64/* These are defined by the linker */
65extern char etext[], edata[], end[];
66char *esym;	/* DDB */
67
68/*
69 * XXX: m68k common code needs these...
70 * ... but this port does not need to deal with anything except
71 * an mc68030, so these two variables are always ignored.
72 * XXX: Need to do something about <m68k/include/cpu.h>
73 */
74int cputype =  1;	/* CPU_68030 */
75int mmutype = -1;	/* MMU_68030 */
76
77/*
78 * Now our own stuff.
79 */
80
81struct user *proc0paddr;	/* proc[0] pcb address (u-area VA) */
82extern struct pcb *curpcb;
83
84/* First C code called by locore.s */
85void _bootstrap __P((struct exec));
86
87static void _vm_init __P((struct exec *kehp));
88
89#if defined(DDB) && !defined(SYMTAB_SPACE)
90static void _save_symtab __P((struct exec *kehp));
91
92/*
93 * Preserve DDB symbols and strings by setting esym.
94 */
95static void
96_save_symtab(kehp)
97	struct exec *kehp;	/* kernel exec header */
98{
99	int x, *symsz, *strsz;
100	char *endp, *errdesc;
101
102	/* Initialize */
103	endp = end;
104	symsz = (int*)end;
105
106	/*
107	 * Sanity-check the exec header.
108	 */
109	errdesc = "bad magic";
110	if ((kehp->a_midmag & 0xFFF0) != 0x0100)
111		goto err;
112
113	/* Boundary between text and data varries a little. */
114	errdesc = "bad header";
115	x = kehp->a_text + kehp->a_data;
116	if (x != (edata - kernel_text))
117		goto err;
118	if (kehp->a_bss != (end - edata))
119		goto err;
120	if (kehp->a_entry != (int)kernel_text)
121		goto err;
122	if (kehp->a_trsize || kehp->a_drsize)
123		goto err;
124	/* The exec header looks OK... */
125
126	/* Check the symtab length word. */
127	errdesc = "bad symbols/strings";
128	if (kehp->a_syms != *symsz)
129		goto err;
130	endp += sizeof(int);	/* past length word */
131	endp += *symsz;			/* past nlist array */
132
133	/* Sanity-check the string table length. */
134	strsz = (int*)endp;
135	if ((*strsz < 4) || (*strsz > 0x80000))
136		goto err;
137	/* OK, we have a valid symbol table. */
138	endp += *strsz;			/* past strings */
139
140	/* Success!  Advance esym past the symbol data. */
141	esym = endp;
142	return;
143
144 err:
145	/*
146	 * Make sure the later call to ddb_init()
147	 * will pass zero as the symbol table size.
148	 */
149	*symsz = 0;
150	mon_printf("_save_symtab: %s\n", errdesc);
151}
152#endif	/* DDB && !SYMTAB_SPACE */
153
154/*
155 * This function is called from _bootstrap() to initialize
156 * pre-vm-sytem virtual memory.  All this really does is to
157 * set virtual_avail to the first page following preloaded
158 * data (i.e. the kernel and its symbol table) and special
159 * things that may be needed very early (proc0 upages).
160 * Once that is done, pmap_bootstrap() is called to do the
161 * usual preparations for our use of the MMU.
162 */
163static void
164_vm_init(kehp)
165	struct exec *kehp;	/* kernel exec header */
166{
167	vm_offset_t nextva;
168
169	/*
170	 * First preserve our symbol table, which might have been
171	 * loaded after our BSS area by the boot loader.  However,
172	 * if DDB is not part of this kernel, ignore the symbols.
173	 */
174	esym = end + 4;
175#if defined(DDB) && !defined(SYMTAB_SPACE)
176	/* This will advance esym past the symbols. */
177	_save_symtab(kehp);
178#endif
179
180	/*
181	 * Steal some special-purpose, already mapped pages.
182	 * Note: msgbuf is setup in machdep.c:cpu_startup()
183	 */
184	nextva = m68k_round_page(esym);
185
186	/*
187	 * Setup the u-area pages (stack, etc.) for proc0.
188	 * This is done very early (here) to make sure the
189	 * fault handler works in case we hit an early bug.
190	 * (The fault handler may reference proc0 stuff.)
191	 */
192	proc0paddr = (struct user *) nextva;
193	nextva += USPACE;
194	bzero((caddr_t)proc0paddr, USPACE);
195	proc0.p_addr = proc0paddr;
196
197	/*
198	 * Now that proc0 exists, make it the "current" one.
199	 */
200	curproc = &proc0;
201	curpcb = &proc0paddr->u_pcb;
202
203	/* This does most of the real work. */
204	pmap_bootstrap(nextva);
205}
206
207/*
208 * This is called from locore.s just after the kernel is remapped
209 * to its proper address, but before the call to main().  The work
210 * done here corresponds to various things done in locore.s on the
211 * hp300 port (and other m68k) but which we prefer to do in C code.
212 * Also do setup specific to the Sun PROM monitor and IDPROM here.
213 */
214void
215_bootstrap(keh)
216	struct exec keh;	/* kernel exec header */
217{
218
219	/* First, Clear BSS. */
220	bzero(edata, end - edata);
221
222	/* Set v_handler, get boothowto. */
223	sunmon_init();
224
225	/* Handle kernel mapping, pmap_bootstrap(), etc. */
226	_vm_init(&keh);
227
228	/*
229	 * Find and save OBIO mappings needed early,
230	 * and call some init functions.
231	 */
232	obio_init();
233
234	/*
235	 * Point interrupts/exceptions to our vector table.
236	 * (Until now, we use the one setup by the PROM.)
237	 *
238	 * This is done after obio_init() / intreg_init() finds
239	 * the interrupt register and disables the NMI clock so
240	 * it will not cause "spurrious level 7" complaints.
241	 * Done after _vm_init so the PROM can debug that.
242	 */
243	setvbr((void **)vector_table);
244	/* Interrupts are enabled later, after autoconfig. */
245
246	/*
247	 * Find the IDPROM and copy it to memory.
248	 * Needs obio_init and setvbr earlier.
249	 */
250	idprom_init();
251
252	/*
253	 * Turn on the LEDs so we know power is on.
254	 * Needs idprom_init and obio_init earlier.
255	 */
256	leds_init();
257}
258