xref: /netbsd/sys/arch/sun3/sun3x/locore2.c (revision c4a72b64)
1 /*	$NetBSD: locore2.c,v 1.27 2002/08/02 18:19:59 soren 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 "opt_ddb.h"
40 
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/proc.h>
44 #include <sys/reboot.h>
45 #include <sys/user.h>
46 #define ELFSIZE 32
47 #include <sys/exec_elf.h>
48 
49 #include <uvm/uvm_extern.h>
50 
51 #include <machine/cpu.h>
52 #include <machine/db_machdep.h>
53 #include <machine/dvma.h>
54 #include <machine/idprom.h>
55 #include <machine/leds.h>
56 #include <machine/mon.h>
57 #include <machine/pmap.h>
58 #include <machine/pte.h>
59 
60 #include <sun3/sun3/interreg.h>
61 #include <sun3/sun3/machdep.h>
62 #include <sun3/sun3/vector.h>
63 
64 /* This is defined in locore.s */
65 extern char kernel_text[];
66 
67 /* These are defined by the linker */
68 extern char etext[], edata[], end[];
69 int nsym;
70 char *ssym, *esym;
71 
72 /*
73  * XXX: m68k common code needs these...
74  * ... but this port does not need to deal with anything except
75  * an mc68030, so these two variables are always ignored.
76  */
77 int cputype = CPU_68030;
78 int mmutype = MMU_68030;
79 
80 /*
81  * Now our own stuff.
82  */
83 
84 struct user *proc0paddr;	/* proc[0] pcb address (u-area VA) */
85 extern struct pcb *curpcb;
86 
87 /* First C code called by locore.s */
88 void _bootstrap __P((void));
89 
90 static void _vm_init __P((void));
91 
92 #if defined(DDB)
93 static void _save_symtab __P((void));
94 
95 /*
96  * Preserve DDB symbols and strings by setting esym.
97  */
98 static void
99 _save_symtab()
100 {
101 	int i;
102 	Elf_Ehdr *ehdr;
103 	Elf_Shdr *shp;
104 	vaddr_t minsym, maxsym;
105 
106 	/*
107 	 * Check the ELF headers.
108 	 */
109 
110 	ehdr = (void *)end;
111 	if (memcmp(ehdr->e_ident, ELFMAG, SELFMAG) != 0 ||
112 	    ehdr->e_ident[EI_CLASS] != ELFCLASS32) {
113 		mon_printf("_save_symtab: bad ELF magic\n");
114 		return;
115 	}
116 
117 	/*
118 	 * Find the end of the symbols and strings.
119 	 */
120 
121 	maxsym = 0;
122 	minsym = ~maxsym;
123 	shp = (Elf_Shdr *)(end + ehdr->e_shoff);
124 	for (i = 0; i < ehdr->e_shnum; i++) {
125 		if (shp[i].sh_type != SHT_SYMTAB &&
126 		    shp[i].sh_type != SHT_STRTAB) {
127 			continue;
128 		}
129 		minsym = min(minsym, (vaddr_t)end + shp[i].sh_offset);
130 		maxsym = max(maxsym, (vaddr_t)end + shp[i].sh_offset +
131 			     shp[i].sh_size);
132 	}
133 	nsym = 1;
134 	ssym = (char *)ehdr;
135 	esym = (char *)maxsym;
136 }
137 #endif	/* DDB */
138 
139 /*
140  * This function is called from _bootstrap() to initialize
141  * pre-vm-sytem virtual memory.  All this really does is to
142  * set virtual_avail to the first page following preloaded
143  * data (i.e. the kernel and its symbol table) and special
144  * things that may be needed very early (proc0 upages).
145  * Once that is done, pmap_bootstrap() is called to do the
146  * usual preparations for our use of the MMU.
147  */
148 static void
149 _vm_init()
150 {
151 	vaddr_t nextva;
152 
153 	/*
154 	 * First preserve our symbol table, which might have been
155 	 * loaded after our BSS area by the boot loader.  However,
156 	 * if DDB is not part of this kernel, ignore the symbols.
157 	 */
158 	esym = end + 4;
159 #if defined(DDB)
160 	/* This will advance esym past the symbols. */
161 	_save_symtab();
162 #endif
163 
164 	/*
165 	 * Steal some special-purpose, already mapped pages.
166 	 * Note: msgbuf is setup in machdep.c:cpu_startup()
167 	 */
168 	nextva = m68k_round_page(esym);
169 
170 	/*
171 	 * Setup the u-area pages (stack, etc.) for proc0.
172 	 * This is done very early (here) to make sure the
173 	 * fault handler works in case we hit an early bug.
174 	 * (The fault handler may reference proc0 stuff.)
175 	 */
176 	proc0paddr = (struct user *) nextva;
177 	nextva += USPACE;
178 	memset((caddr_t)proc0paddr, 0, USPACE);
179 	proc0.p_addr = proc0paddr;
180 
181 	/*
182 	 * Now that proc0 exists, make it the "current" one.
183 	 */
184 	curproc = &proc0;
185 	curpcb = &proc0paddr->u_pcb;
186 
187 	/* This does most of the real work. */
188 	pmap_bootstrap(nextva);
189 }
190 
191 /*
192  * This is called from locore.s just after the kernel is remapped
193  * to its proper address, but before the call to main().  The work
194  * done here corresponds to various things done in locore.s on the
195  * hp300 port (and other m68k) but which we prefer to do in C code.
196  * Also do setup specific to the Sun PROM monitor and IDPROM here.
197  */
198 void
199 _bootstrap()
200 {
201 
202 	/* First, Clear BSS. */
203 	memset(edata, 0, end - edata);
204 
205 	/* Set v_handler, get boothowto. */
206 	sunmon_init();
207 
208 	/* Handle kernel mapping, pmap_bootstrap(), etc. */
209 	_vm_init();
210 
211 	/*
212 	 * Find and save OBIO mappings needed early,
213 	 * and call some init functions.
214 	 */
215 	obio_init();
216 
217 	/*
218 	 * Point interrupts/exceptions to our vector table.
219 	 * (Until now, we use the one setup by the PROM.)
220 	 *
221 	 * This is done after obio_init() / intreg_init() finds
222 	 * the interrupt register and disables the NMI clock so
223 	 * it will not cause "spurrious level 7" complaints.
224 	 * Done after _vm_init so the PROM can debug that.
225 	 */
226 	setvbr((void **)vector_table);
227 	/* Interrupts are enabled later, after autoconfig. */
228 
229 	/*
230 	 * Find the IDPROM and copy it to memory.
231 	 * Needs obio_init and setvbr earlier.
232 	 */
233 	idprom_init();
234 
235 	/*
236 	 * Turn on the LEDs so we know power is on.
237 	 * Needs idprom_init and obio_init earlier.
238 	 */
239 	leds_init();
240 }
241