xref: /netbsd-src/sys/arch/sun3/sun3x/locore2.c (revision 81e0d2b0af8485d94ed5da487d4253841a2e6e45)
1 /*	$NetBSD: locore2.c,v 1.30 2005/01/22 15:36:11 chs 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/cdefs.h>
40 __KERNEL_RCSID(0, "$NetBSD: locore2.c,v 1.30 2005/01/22 15:36:11 chs Exp $");
41 
42 #include "opt_ddb.h"
43 
44 #include <sys/param.h>
45 #include <sys/systm.h>
46 #include <sys/proc.h>
47 #include <sys/reboot.h>
48 #include <sys/user.h>
49 #define ELFSIZE 32
50 #include <sys/exec_elf.h>
51 
52 #include <uvm/uvm_extern.h>
53 
54 #include <machine/cpu.h>
55 #include <machine/db_machdep.h>
56 #include <machine/dvma.h>
57 #include <machine/idprom.h>
58 #include <machine/leds.h>
59 #include <machine/mon.h>
60 #include <machine/pmap.h>
61 #include <machine/pte.h>
62 
63 #include <sun3/sun3/interreg.h>
64 #include <sun3/sun3/machdep.h>
65 #include <sun3/sun3/vector.h>
66 
67 /* This is defined in locore.s */
68 extern char kernel_text[];
69 
70 /* These are defined by the linker */
71 extern char etext[], edata[], end[];
72 int nsym;
73 char *ssym, *esym;
74 
75 /*
76  * XXX: m68k common code needs these...
77  * ... but this port does not need to deal with anything except
78  * an mc68030, so these two variables are always ignored.
79  */
80 int cputype = CPU_68030;
81 int mmutype = MMU_68030;
82 
83 /*
84  * Now our own stuff.
85  */
86 
87 struct user *proc0paddr;	/* proc[0] pcb address (u-area VA) */
88 extern struct pcb *curpcb;
89 
90 /* First C code called by locore.s */
91 void _bootstrap(void);
92 
93 static void _vm_init(void);
94 
95 #if defined(DDB)
96 static void _save_symtab(void);
97 
98 /*
99  * Preserve DDB symbols and strings by setting esym.
100  */
101 static void
102 _save_symtab(void)
103 {
104 	int i;
105 	Elf_Ehdr *ehdr;
106 	Elf_Shdr *shp;
107 	vaddr_t minsym, maxsym;
108 
109 	/*
110 	 * Check the ELF headers.
111 	 */
112 
113 	ehdr = (void *)end;
114 	if (memcmp(ehdr->e_ident, ELFMAG, SELFMAG) != 0 ||
115 	    ehdr->e_ident[EI_CLASS] != ELFCLASS32) {
116 		mon_printf("_save_symtab: bad ELF magic\n");
117 		return;
118 	}
119 
120 	/*
121 	 * Find the end of the symbols and strings.
122 	 */
123 
124 	maxsym = 0;
125 	minsym = ~maxsym;
126 	shp = (Elf_Shdr *)(end + ehdr->e_shoff);
127 	for (i = 0; i < ehdr->e_shnum; i++) {
128 		if (shp[i].sh_type != SHT_SYMTAB &&
129 		    shp[i].sh_type != SHT_STRTAB) {
130 			continue;
131 		}
132 		minsym = min(minsym, (vaddr_t)end + shp[i].sh_offset);
133 		maxsym = max(maxsym, (vaddr_t)end + shp[i].sh_offset +
134 			     shp[i].sh_size);
135 	}
136 	nsym = 1;
137 	ssym = (char *)ehdr;
138 	esym = (char *)maxsym;
139 }
140 #endif	/* DDB */
141 
142 /*
143  * This function is called from _bootstrap() to initialize
144  * pre-vm-sytem virtual memory.  All this really does is to
145  * set virtual_avail to the first page following preloaded
146  * data (i.e. the kernel and its symbol table) and special
147  * things that may be needed very early (lwp0 upages).
148  * Once that is done, pmap_bootstrap() is called to do the
149  * usual preparations for our use of the MMU.
150  */
151 static void
152 _vm_init(void)
153 {
154 	vaddr_t nextva;
155 
156 	/*
157 	 * First preserve our symbol table, which might have been
158 	 * loaded after our BSS area by the boot loader.  However,
159 	 * if DDB is not part of this kernel, ignore the symbols.
160 	 */
161 	esym = end + 4;
162 #if defined(DDB)
163 	/* This will advance esym past the symbols. */
164 	_save_symtab();
165 #endif
166 
167 	/*
168 	 * Steal some special-purpose, already mapped pages.
169 	 * Note: msgbuf is setup in machdep.c:cpu_startup()
170 	 */
171 	nextva = m68k_round_page(esym);
172 
173 	/*
174 	 * Setup the u-area pages (stack, etc.) for lwp0.
175 	 * This is done very early (here) to make sure the
176 	 * fault handler works in case we hit an early bug.
177 	 * (The fault handler may reference lwp0 stuff.)
178 	 */
179 	proc0paddr = (struct user *) nextva;
180 	nextva += USPACE;
181 	memset((caddr_t)proc0paddr, 0, USPACE);
182 	lwp0.l_addr = proc0paddr;
183 
184 	/*
185 	 * Now that lwp0 exists, make it the "current" one.
186 	 */
187 	curlwp = &lwp0;
188 	curpcb = &proc0paddr->u_pcb;
189 
190 	/* This does most of the real work. */
191 	pmap_bootstrap(nextva);
192 }
193 
194 /*
195  * This is called from locore.s just after the kernel is remapped
196  * to its proper address, but before the call to main().  The work
197  * done here corresponds to various things done in locore.s on the
198  * hp300 port (and other m68k) but which we prefer to do in C code.
199  * Also do setup specific to the Sun PROM monitor and IDPROM here.
200  */
201 void
202 _bootstrap(void)
203 {
204 
205 	/* First, Clear BSS. */
206 	memset(edata, 0, end - edata);
207 
208 	/* Set v_handler, get boothowto. */
209 	sunmon_init();
210 
211 	/* Handle kernel mapping, pmap_bootstrap(), etc. */
212 	_vm_init();
213 
214 	/*
215 	 * Find and save OBIO mappings needed early,
216 	 * and call some init functions.
217 	 */
218 	obio_init();
219 
220 	/*
221 	 * Point interrupts/exceptions to our vector table.
222 	 * (Until now, we use the one setup by the PROM.)
223 	 *
224 	 * This is done after obio_init() / intreg_init() finds
225 	 * the interrupt register and disables the NMI clock so
226 	 * it will not cause "spurrious level 7" complaints.
227 	 * Done after _vm_init so the PROM can debug that.
228 	 */
229 	setvbr((void **)vector_table);
230 	/* Interrupts are enabled later, after autoconfig. */
231 
232 	/*
233 	 * Find the IDPROM and copy it to memory.
234 	 * Needs obio_init and setvbr earlier.
235 	 */
236 	idprom_init();
237 
238 	/*
239 	 * Turn on the LEDs so we know power is on.
240 	 * Needs idprom_init and obio_init earlier.
241 	 */
242 	leds_init();
243 }
244