1 /* $NetBSD: locore2.c,v 1.43 2024/01/13 18:51:38 thorpej 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 *
19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29 * POSSIBILITY OF SUCH DAMAGE.
30 */
31
32 #include <sys/cdefs.h>
33 __KERNEL_RCSID(0, "$NetBSD: locore2.c,v 1.43 2024/01/13 18:51:38 thorpej Exp $");
34
35 #include "opt_ddb.h"
36
37 #include <sys/param.h>
38 #include <sys/systm.h>
39 #include <sys/proc.h>
40 #include <sys/reboot.h>
41 #define ELFSIZE 32
42 #include <sys/exec_elf.h>
43
44 #include <uvm/uvm_extern.h>
45
46 #include <dev/cons.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 #include <machine/vectors.h>
57
58 #include <sun3/sun3/interreg.h>
59 #include <sun3/sun3/machdep.h>
60
61 /* This is defined in locore.s */
62 extern char kernel_text[];
63
64 /* These are defined by the linker */
65 extern char etext[], edata[], end[];
66 int nsym;
67 char *ssym, *esym;
68
69 /*
70 * XXX: m68k common code needs these...
71 * ... but this port does not need to deal with anything except
72 * an mc68030, so these two variables are always ignored.
73 */
74 int cputype = CPU_68030;
75 int mmutype = MMU_68030;
76
77 /*
78 * Now our own stuff.
79 */
80
81 extern struct pcb *curpcb;
82
83 /* First C code called by locore.s */
84 void _bootstrap(void);
85
86 static void _vm_init(void);
87
88 #if defined(DDB)
89 static void _save_symtab(void);
90
91 /*
92 * Preserve DDB symbols and strings by setting esym.
93 */
94 static void
_save_symtab(void)95 _save_symtab(void)
96 {
97 int i;
98 Elf_Ehdr *ehdr;
99 Elf_Shdr *shp;
100 vaddr_t minsym, maxsym;
101
102 /*
103 * Check the ELF headers.
104 */
105
106 ehdr = (void *)end;
107 if (memcmp(ehdr->e_ident, ELFMAG, SELFMAG) != 0 ||
108 ehdr->e_ident[EI_CLASS] != ELFCLASS32) {
109 mon_printf("_save_symtab: bad ELF magic\n");
110 return;
111 }
112
113 /*
114 * Find the end of the symbols and strings.
115 */
116
117 maxsym = 0;
118 minsym = ~maxsym;
119 shp = (Elf_Shdr *)(end + ehdr->e_shoff);
120 for (i = 0; i < ehdr->e_shnum; i++) {
121 if (shp[i].sh_type != SHT_SYMTAB &&
122 shp[i].sh_type != SHT_STRTAB) {
123 continue;
124 }
125 minsym = uimin(minsym, (vaddr_t)end + shp[i].sh_offset);
126 maxsym = uimax(maxsym, (vaddr_t)end + shp[i].sh_offset +
127 shp[i].sh_size);
128 }
129 nsym = 1;
130 ssym = (char *)ehdr;
131 esym = (char *)maxsym;
132 }
133 #endif /* DDB */
134
135 /*
136 * This function is called from _bootstrap() to initialize
137 * pre-vm-system virtual memory. All this really does is to
138 * set virtual_avail to the first page following preloaded
139 * data (i.e. the kernel and its symbol table) and special
140 * things that may be needed very early (lwp0 upages).
141 * Once that is done, pmap_bootstrap() is called to do the
142 * usual preparations for our use of the MMU.
143 */
144 static void
_vm_init(void)145 _vm_init(void)
146 {
147 vaddr_t nextva;
148
149 /*
150 * First preserve our symbol table, which might have been
151 * loaded after our BSS area by the boot loader. However,
152 * if DDB is not part of this kernel, ignore the symbols.
153 */
154 esym = end + 4;
155 #if defined(DDB)
156 /* This will advance esym past the symbols. */
157 _save_symtab();
158 #endif
159
160 /*
161 * Steal some special-purpose, already mapped pages.
162 * Note: msgbuf is setup in machdep.c:cpu_startup()
163 */
164 nextva = m68k_round_page(esym);
165
166 /*
167 * Setup the u-area pages (stack, etc.) for lwp0.
168 * This is done very early (here) to make sure the
169 * fault handler works in case we hit an early bug.
170 * (The fault handler may reference lwp0 stuff.)
171 */
172 uvm_lwp_setuarea(&lwp0, nextva);
173 memset((void *)nextva, 0, USPACE);
174
175 nextva += USPACE;
176
177 /*
178 * Now that lwp0 exists, make it the "current" one.
179 */
180 curlwp = &lwp0;
181 curpcb = lwp_getpcb(&lwp0);
182
183 /* This does most of the real work. */
184 pmap_bootstrap(nextva);
185 }
186
187 /*
188 * This is called from locore.s just after the kernel is remapped
189 * to its proper address, but before the call to main(). The work
190 * done here corresponds to various things done in locore.s on the
191 * hp300 port (and other m68k) but which we prefer to do in C code.
192 * Also do setup specific to the Sun PROM monitor and IDPROM here.
193 */
194 void
_bootstrap(void)195 _bootstrap(void)
196 {
197 extern struct consdev consdev_prom; /* XXX */
198
199 /* First, Clear BSS. */
200 memset(edata, 0, end - edata);
201
202 /* Set v_handler, get boothowto. */
203 sunmon_init();
204
205 /*
206 * Initialize console to point to the PROM (output only) table
207 * for early printf calls.
208 */
209 cn_tab = &consdev_prom;
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 vec_init();
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