elf64_freebsd.c revision 114379 
1/*-
2 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: head/sys/boot/i386/libi386/elf64_freebsd.c 114379 2003-05-01 03:56:30Z peter $
27 */
28
29#define __ELF_WORD_SIZE 64
30#include <sys/param.h>
31#include <sys/exec.h>
32#include <sys/linker.h>
33#include <string.h>
34#include <machine/bootinfo.h>
35#include <machine/elf.h>
36#include <stand.h>
37
38#include "bootstrap.h"
39#include "libi386.h"
40#include "btxv86.h"
41
42static int	elf64_exec(struct preloaded_file *amp);
43
44struct file_format amd64_elf = { elf64_loadfile, elf64_exec };
45
46#define PG_V	0x001
47#define PG_RW	0x002
48#define PG_U	0x004
49#define PG_PS	0x080
50
51typedef u_int64_t p4_entry_t;
52typedef u_int64_t p3_entry_t;
53typedef u_int64_t p2_entry_t;
54extern p4_entry_t PT4[];
55extern p3_entry_t PT3[];
56extern p2_entry_t PT2[];
57
58u_int32_t entry_hi;
59u_int32_t entry_lo;
60
61extern amd64_tramp();
62
63/*
64 * There is an a.out kernel and one or more a.out modules loaded.
65 * We wish to start executing the kernel image, so make such
66 * preparations as are required, and do so.
67 */
68static int
69elf64_exec(struct preloaded_file *fp)
70{
71    struct file_metadata	*md;
72    Elf_Ehdr 			*ehdr;
73    vm_offset_t			modulep, kernend;
74    int				err;
75    int				i;
76
77    if ((md = file_findmetadata(fp, MODINFOMD_ELFHDR)) == NULL)
78	return(EFTYPE);			/* XXX actually EFUCKUP */
79    ehdr = (Elf_Ehdr *)&(md->md_data);
80
81    err = bi_load64(fp->f_args, &modulep, &kernend);
82    if (err != 0)
83	return(err);
84
85    bzero(PT4, PAGE_SIZE);
86    bzero(PT3, PAGE_SIZE);
87    bzero(PT2, PAGE_SIZE);
88
89    /* single PML4 entry */
90    PT4[0] = (p4_entry_t)VTOP((uintptr_t)&PT3[0]);
91    PT4[0] |= PG_V | PG_RW | PG_U;
92
93    /* Direct map 1GB at address zero */
94    PT3[0] = (p3_entry_t)VTOP((uintptr_t)&PT2[0]);
95    PT3[0] |= PG_V | PG_RW | PG_U;
96
97    /* Direct map 1GB at KERNBASE (hardcoded for now) */
98    PT3[1] = (p3_entry_t)VTOP((uintptr_t)&PT2[0]);
99    PT3[1] |= PG_V | PG_RW | PG_U;
100
101    /* 512 PG_PS (2MB) page mappings for 1GB of direct mapping */
102    for (i = 0; i < 512; i++) {
103	PT2[i] = i * (2 * 1024 * 1024);
104	PT2[i] |= PG_V | PG_RW | PG_PS | PG_U;
105    }
106
107    entry_lo = ehdr->e_entry & 0xffffffff;
108    entry_hi = (ehdr->e_entry >> 32) & 0xffffffff;
109#ifdef DEBUG
110    printf("Start @ %#llx ...\n", ehdr->e_entry);
111#endif
112
113    dev_cleanup();
114    __exec((void *)VTOP(amd64_tramp), modulep, kernend);
115
116    panic("exec returned");
117}
118