locore2.c revision 1.14
1/*	$NetBSD: locore2.c,v 1.14 1997/04/25 18:29:58 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/mon.h>
52#include <machine/pte.h>
53#include <machine/pmap.h>
54#include <machine/obio.h>
55#include <machine/machdep.h>
56
57#include <sun3/sun3/interreg.h>
58#include <sun3/sun3/vector.h>
59
60/* This is defined in locore.s */
61extern char kernel_text[];
62
63/* These are defined by the linker */
64extern char etext[], edata[], end[];
65char *esym;	/* DDB */
66
67/*
68 * XXX: m68k common code needs these...
69 * ... but this port does not need to deal with anything except
70 * an mc68030, so these two variables are always ignored.
71 * XXX: Need to do something about <m68k/include/cpu.h>
72 */
73int cputype =  1;	/* CPU_68030 */
74int mmutype = -1;	/* MMU_68030 */
75
76/*
77 * Now our own stuff.
78 */
79
80struct user *proc0paddr;	/* proc[0] pcb address (u-area VA) */
81extern struct pcb *curpcb;
82
83/* First C code called by locore.s */
84void _bootstrap __P((struct exec));
85
86static void _vm_init __P((struct exec *kehp));
87
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;
101	char *errdesc = "?";
102
103	/*
104	 * First, sanity-check the exec header.
105	 */
106	if ((kehp->a_midmag & 0xFFF0) != 0x0100) {
107		errdesc = "magic";
108		goto err;
109	}
110	/* Boundary between text and data varries a little. */
111	x = kehp->a_text + kehp->a_data;
112	if (x != (edata - kernel_text)) {
113		errdesc = "a_text+a_data";
114		goto err;
115	}
116	if (kehp->a_bss != (end - edata)) {
117		errdesc = "a_bss";
118		goto err;
119	}
120	if (kehp->a_entry != (int)kernel_text) {
121		errdesc = "a_entry";
122		goto err;
123	}
124	if (kehp->a_trsize || kehp->a_drsize) {
125		errdesc = "a_Xrsize";
126		goto err;
127	}
128	/* The exec header looks OK... */
129
130	/* Check the symtab length word. */
131	endp = end;
132	symsz = (int*)endp;
133	if (kehp->a_syms != *symsz) {
134		errdesc = "a_syms";
135		goto err;
136	}
137	endp += sizeof(int);	/* past length word */
138	endp += *symsz;			/* past nlist array */
139
140	/* Sanity-check the string table length. */
141	strsz = (int*)endp;
142	if ((*strsz < 4) || (*strsz > 0x80000)) {
143		errdesc = "strsize";
144		goto err;
145	}
146
147	/* Success!  We have a valid symbol table! */
148	endp += *strsz;			/* past strings */
149	esym = endp;
150	return;
151
152 err:
153	mon_printf("_save_symtab: bad %s\n", errdesc);
154}
155#endif	/* DDB && !SYMTAB_SPACE */
156
157/*
158 * This function is called from _bootstrap() to initialize
159 * pre-vm-sytem virtual memory.  All this really does is to
160 * set virtual_avail to the first page following preloaded
161 * data (i.e. the kernel and its symbol table) and special
162 * things that may be needed very early (proc0 upages).
163 * Once that is done, pmap_bootstrap() is called to do the
164 * usual preparations for our use of the MMU.
165 */
166static void
167_vm_init(kehp)
168	struct exec *kehp;	/* kernel exec header */
169{
170	vm_offset_t nextva;
171
172	/*
173	 * First, reserve our symbol table which might have been
174	 * loaded after our BSS area by the boot loader.  However,
175	 * if DDB is not part of this kernel, ignore the symbols.
176	 */
177	esym = end;
178#if defined(DDB) && !defined(SYMTAB_SPACE)
179	/* This will advance esym past the symbols. */
180	_save_symtab(kehp);
181#endif
182
183	/*
184	 * Steal some special-purpose, already mapped pages.
185	 * Note: msgbuf is setup in machdep.c:cpu_startup()
186	 */
187	nextva = _round_page(esym);
188
189	/*
190	 * Setup the u-area pages (stack, etc.) for proc0.
191	 * This is done very early (here) to make sure the
192	 * fault handler works in case we hit an early bug.
193	 * (The fault handler may reference proc0 stuff.)
194	 */
195	proc0paddr = (struct user *) nextva;
196	nextva += USPACE;
197	bzero((caddr_t)proc0paddr, USPACE);
198	proc0.p_addr = proc0paddr;
199
200	/*
201	 * Now that proc0 exists, make it the "current" one.
202	 */
203	curproc = &proc0;
204	curpcb = &proc0paddr->u_pcb;
205
206	/*
207	 * Call pmap_bootstrap() so that we may begin using
208	 * pmap_enter_kernel() and pmap_bootstrap_alloc().
209	 */
210	pmap_bootstrap(nextva);
211}
212
213
214/*
215 * This is called from locore.s just after the kernel is remapped
216 * to its proper address, but before the call to main().  The work
217 * done here corresponds to various things done in locore.s on the
218 * hp300 port (and other m68k) but which we prefer to do in C code.
219 * Also do setup specific to the Sun PROM monitor and IDPROM here.
220 */
221void
222_bootstrap(keh)
223	struct exec keh;	/* kernel exec header */
224{
225
226	/* First, Clear BSS. */
227	bzero(edata, end - edata);
228
229	/* set v_handler, get boothowto */
230	sunmon_init();
231
232	/*
233	 * Find and save OBIO mappings needed early,
234	 * and call some init functions.
235	 */
236	obio_init();
237
238	/* handle kernel mapping, pmap_bootstrap(), etc. */
239	_vm_init(&keh);
240
241	/*
242	 * Point interrupts/exceptions to our vector table.
243	 * (Until now, we use the one setup by the PROM.)
244	 *
245	 * This is done after obio_init() / intreg_init() finds
246	 * the interrupt register and disables the NMI clock so
247	 * it will not cause "spurrious level 7" complaints.
248	 * Done after _vm_init so the PROM can debug that.
249	 */
250	setvbr((void **)vector_table);
251
252	/* Interrupts are enabled later, after autoconfig. */
253}
254