sys/arch/sun3/sun3x/locore2.c

   1 /*      $NetBSD: locore2.c,v 1.37 2009/11/27 03:23:14 rmind 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 1.37 2009/11/27 03:23:14 rmind 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 <machine/cpu.h>
  47 #include <machine/db_machdep.h>
  48 #include <machine/dvma.h>
  49 #include <machine/idprom.h>
  50 #include <machine/leds.h>
  51 #include <machine/mon.h>
  52 #include <machine/pmap.h>
  53 #include <machine/pte.h>
  54
  55 #include <sun3/sun3/interreg.h>
  56 #include <sun3/sun3/machdep.h>
  57 #include <sun68k/sun68k/vector.h>
  58
  59 /* This is defined in locore.s */
  60 extern char kernel_text[];
  61
  62 /* These are defined by the linker */
  63 extern char etext[], edata[], end[];
  64 int nsym;
  65 char *ssym, *esym;
  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  */
  72 int cputype = CPU_68030;
  73 int mmutype = MMU_68030;
  74
  75 /*
  76  * Now our own stuff.
  77  */
  78
  79 extern struct pcb *curpcb;
  80
  81 /* First C code called by locore.s */
  82 void _bootstrap(void);
  83
  84 static void _vm_init(void);
  85
  86 #if defined(DDB)
  87 static void _save_symtab(void);
  88
  89 /*
  90  * Preserve DDB symbols and strings by setting esym.
  91  */
  92 static void
  93 _save_symtab(void)
  94 {
  95         int i;
  96         Elf_Ehdr *ehdr;
  97         Elf_Shdr *shp;
  98         vaddr_t minsym, maxsym;
  99
 100         /*
 101          * Check the ELF headers.
 102          */
 103
 104         ehdr = (void *)end;
 105         if (memcmp(ehdr->e_ident, ELFMAG, SELFMAG) != 0 ||
 106             ehdr->e_ident[EI_CLASS] != ELFCLASS32) {
 107                 mon_printf("_save_symtab: bad ELF magic\n");
 108                 return;
 109         }
 110
 111         /*
 112          * Find the end of the symbols and strings.
 113          */
 114
 115         maxsym = 0;
 116         minsym = ~maxsym;
 117         shp = (Elf_Shdr *)(end + ehdr->e_shoff);
 118         for (i = 0; i < ehdr->e_shnum; i++) {
 119                 if (shp[i].sh_type != SHT_SYMTAB &&
 120                     shp[i].sh_type != SHT_STRTAB) {
 121                         continue;
 122                 }
 123                 minsym = min(minsym, (vaddr_t)end + shp[i].sh_offset);
 124                 maxsym = max(maxsym, (vaddr_t)end + shp[i].sh_offset +
 125                              shp[i].sh_size);
 126         }
 127         nsym = 1;
 128         ssym = (char *)ehdr;
 129         esym = (char *)maxsym;
 130 }
 131 #endif  /* DDB */
 132
 133 /*
 134  * This function is called from _bootstrap() to initialize
 135  * pre-vm-sytem virtual memory.  All this really does is to
 136  * set virtual_avail to the first page following preloaded
 137  * data (i.e. the kernel and its symbol table) and special
 138  * things that may be needed very early (lwp0 upages).
 139  * Once that is done, pmap_bootstrap() is called to do the
 140  * usual preparations for our use of the MMU.
 141  */
 142 static void
 143 _vm_init(void)
 144 {
 145         vaddr_t nextva;
 146
 147         /*
 148          * First preserve our symbol table, which might have been
 149          * loaded after our BSS area by the boot loader.  However,
 150          * if DDB is not part of this kernel, ignore the symbols.
 151          */
 152         esym = end + 4;
 153 #if defined(DDB)
 154         /* This will advance esym past the symbols. */
 155         _save_symtab();
 156 #endif
 157
 158         /*
 159          * Steal some special-purpose, already mapped pages.
 160          * Note: msgbuf is setup in machdep.c:cpu_startup()
 161          */
 162         nextva = m68k_round_page(esym);
 163
 164         /*
 165          * Setup the u-area pages (stack, etc.) for lwp0.
 166          * This is done very early (here) to make sure the
 167          * fault handler works in case we hit an early bug.
 168          * (The fault handler may reference lwp0 stuff.)
 169          */
 170         uvm_lwp_setuarea(&lwp0, nextva);
 171         memset((void *)nextva, 0, USPACE);
 172
 173         nextva += USPACE;
 174
 175         /*
 176          * Now that lwp0 exists, make it the "current" one.
 177          */
 178         curlwp = &lwp0;
 179         curpcb = lwp_getpcb(&lwp0);
 180
 181         /* This does most of the real work. */
 182         pmap_bootstrap(nextva);
 183 }
 184
 185 /*
 186  * This is called from locore.s just after the kernel is remapped
 187  * to its proper address, but before the call to main().  The work
 188  * done here corresponds to various things done in locore.s on the
 189  * hp300 port (and other m68k) but which we prefer to do in C code.
 190  * Also do setup specific to the Sun PROM monitor and IDPROM here.
 191  */
 192 void
 193 _bootstrap(void)
 194 {
 195
 196         /* First, Clear BSS. */
 197         memset(edata, 0, end - edata);
 198
 199         /* Set v_handler, get boothowto. */
 200         sunmon_init();
 201
 202         /* Handle kernel mapping, pmap_bootstrap(), etc. */
 203         _vm_init();
 204
 205         /*
 206          * Find and save OBIO mappings needed early,
 207          * and call some init functions.
 208          */
 209         obio_init();
 210
 211         /*
 212          * Point interrupts/exceptions to our vector table.
 213          * (Until now, we use the one setup by the PROM.)
 214          *
 215          * This is done after obio_init() / intreg_init() finds
 216          * the interrupt register and disables the NMI clock so
 217          * it will not cause "spurrious level 7" complaints.
 218          * Done after _vm_init so the PROM can debug that.
 219          */
 220         setvbr((void **)vector_table);
 221         /* Interrupts are enabled later, after autoconfig. */
 222
 223         /*
 224          * Find the IDPROM and copy it to memory.
 225          * Needs obio_init and setvbr earlier.
 226          */
 227         idprom_init();
 228
 229         /*
 230          * Turn on the LEDs so we know power is on.
 231          * Needs idprom_init and obio_init earlier.
 232          */
 233         leds_init();
 234 }