locore2.c revision 1.13
1/*	$NetBSD: locore2.c,v 1.13 1997/03/24 17:57:12 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/idprom.h>
55#include <machine/obio.h>
56#include <machine/machdep.h>
57
58#include <sun3/sun3/interreg.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
81unsigned char cpu_machine_id = 0;
82char *cpu_string = NULL;
83int cpu_has_vme = 0;
84int has_iocache = 0;
85
86int msgbufmapped = 0;
87struct msgbuf *msgbufp = NULL;
88
89struct user *proc0paddr;	/* proc[0] pcb address (u-area VA) */
90extern struct pcb *curpcb;
91
92/* First C code called by locore.s */
93void _bootstrap __P((struct exec));
94
95static void _verify_hardware __P((void));
96static void _vm_init __P((struct exec *kehp));
97
98
99#if defined(DDB) && !defined(SYMTAB_SPACE)
100static void _save_symtab __P((struct exec *kehp));
101
102/*
103 * Preserve DDB symbols and strings by setting esym.
104 */
105static void
106_save_symtab(kehp)
107	struct exec *kehp;	/* kernel exec header */
108{
109	int x, *symsz, *strsz;
110	char *endp;
111	char *errdesc = "?";
112
113	/*
114	 * First, sanity-check the exec header.
115	 */
116	mon_printf("_save_symtab: ");
117	if ((kehp->a_midmag & 0xFFF0) != 0x0100) {
118		errdesc = "magic";
119		goto err;
120	}
121	/* Boundary between text and data varries a little. */
122	x = kehp->a_text + kehp->a_data;
123	if (x != (edata - kernel_text)) {
124		errdesc = "a_text+a_data";
125		goto err;
126	}
127	if (kehp->a_bss != (end - edata)) {
128		errdesc = "a_bss";
129		goto err;
130	}
131	if (kehp->a_entry != (int)kernel_text) {
132		errdesc = "a_entry";
133		goto err;
134	}
135	if (kehp->a_trsize || kehp->a_drsize) {
136		errdesc = "a_Xrsize";
137		goto err;
138	}
139	/* The exec header looks OK... */
140
141	/* Check the symtab length word. */
142	endp = end;
143	symsz = (int*)endp;
144	if (kehp->a_syms != *symsz) {
145		errdesc = "a_syms";
146		goto err;
147	}
148	endp += sizeof(int);	/* past length word */
149	endp += *symsz;			/* past nlist array */
150
151	/* Check the string table length. */
152	strsz = (int*)endp;
153	if ((*strsz < 4) || (*strsz > 0x80000)) {
154		errdesc = "strsize";
155		goto err;
156	}
157
158	/* Success!  We have a valid symbol table! */
159	endp += *strsz;			/* past strings */
160	esym = endp;
161	mon_printf(" found %d + %d\n", *symsz, *strsz);
162	return;
163
164 err:
165	mon_printf(" no symbols (bad %s)\n", errdesc);
166}
167#endif	/* DDB && !SYMTAB_SPACE */
168
169/*
170 * This function is called from _bootstrap() to initialize
171 * pre-vm-sytem virtual memory.  All this really does is to
172 * set virtual_avail to the first page following preloaded
173 * data (i.e. the kernel and its symbol table) and special
174 * things that may be needed very early (proc0 upages).
175 * Once that is done, pmap_bootstrap() is called to do the
176 * usual preparations for our use of the MMU.
177 */
178static void
179_vm_init(kehp)
180	struct exec *kehp;	/* kernel exec header */
181{
182	vm_offset_t nextva;
183
184	/*
185	 * First, reserve our symbol table which might have been
186	 * loaded after our BSS area by the boot loader.  However,
187	 * if DDB is not part of this kernel, ignore the symbols.
188	 */
189	esym = end;
190#if defined(DDB) && !defined(SYMTAB_SPACE)
191	/* This will advance esym past the symbols. */
192	_save_symtab(kehp);
193#endif
194
195	/*
196	 * Steal some special-purpose, already mapped pages.
197	 * Note: msgbuf is setup in machdep.c:cpu_startup()
198	 */
199	nextva = _round_page(esym);
200
201	/*
202	 * Setup the u-area pages (stack, etc.) for proc0.
203	 * This is done very early (here) to make sure the
204	 * fault handler works in case we hit an early bug.
205	 * (The fault handler may reference proc0 stuff.)
206	 */
207	proc0paddr = (struct user *) nextva;
208	nextva += USPACE;
209	bzero((caddr_t)proc0paddr, USPACE);
210	proc0.p_addr = proc0paddr;
211
212	/*
213	 * Now that proc0 exists, make it the "current" one.
214	 */
215	curproc = &proc0;
216	curpcb = &proc0paddr->u_pcb;
217
218	/*
219	 * Call pmap_bootstrap() so that we may begin using
220	 * pmap_enter_kernel() and pmap_bootstrap_alloc().
221	 */
222	pmap_bootstrap(nextva);
223}
224
225
226/*
227 * XXX - Should empirically estimate the divisor...
228 * Note that the value of delay_divisor is roughly
229 * 2048 / cpuclock	(where cpuclock is in MHz).
230 */
231int delay_divisor = 82;		/* assume the fastest (3/260) */
232
233static void
234_verify_hardware()
235{
236	unsigned char machtype;
237
238	machtype = identity_prom.idp_machtype;
239	if ((machtype & CPU_ARCH_MASK) != SUN3X_ARCH) {
240		mon_printf("not a sun3x?\n");
241		sunmon_abort();
242	}
243
244	cpu_machine_id = machtype & SUN3X_IMPL_MASK;
245	switch (cpu_machine_id) {
246
247	case SUN3X_MACH_80 :
248		cpu_string = "80";  	/* Hydra */
249		delay_divisor = 102;	/* 20 MHz ? XXX */
250		cpu_has_vme = FALSE;
251		break;
252
253	case SUN3X_MACH_470:
254		cpu_string = "470"; 	/* Pegasus */
255		delay_divisor = 82; 	/* 25 MHz ? XXX */
256		cpu_has_vme = TRUE;
257		break;
258
259	default:
260		mon_printf("unknown sun3x model\n");
261		sunmon_abort();
262	}
263}
264
265
266/*
267 * This is called from locore.s just after the kernel is remapped
268 * to its proper address, but before the call to main().  The work
269 * done here corresponds to various things done in locore.s on the
270 * hp300 port (and other m68k) but which we prefer to do in C code.
271 * Also do setup specific to the Sun PROM monitor and IDPROM here.
272 */
273void
274_bootstrap(keh)
275	struct exec keh;	/* kernel exec header */
276{
277
278	/* First, Clear BSS. */
279	bzero(edata, end - edata);
280
281	/* set v_handler, get boothowto */
282	sunmon_init();
283
284	/* Find devices we need early (like the IDPROM). */
285	obio_init();
286
287	/* Note: must come after obio_init (for IDPROM). */
288	_verify_hardware();	/* get CPU type, etc. */
289
290	/* handle kernel mapping, pmap_bootstrap(), etc. */
291	_vm_init(&keh);
292
293	/*
294	 * Point interrupts/exceptions to our vector table.
295	 * (Until now, we use the one setup by the PROM.)
296	 *
297	 * This is done after obio_init() / intreg_init() finds
298	 * the interrupt register and disables the NMI clock so
299	 * it will not cause "spurrious level 7" complaints.
300	 */
301	setvbr((void **)vector_table);
302
303	/* Interrupts are enabled later, after autoconfig. */
304}
305