bootinfo64.c revision 183667
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
27#include <sys/cdefs.h>
28__FBSDID("$FreeBSD: head/sys/boot/i386/libi386/bootinfo64.c 183667 2008-10-07 14:05:42Z jhb $");
29
30#include <stand.h>
31#include <sys/param.h>
32#include <sys/reboot.h>
33#include <sys/linker.h>
34#include <machine/bootinfo.h>
35#include <machine/cpufunc.h>
36#include <machine/psl.h>
37#include <machine/specialreg.h>
38#include "bootstrap.h"
39#include "libi386.h"
40#include "btxv86.h"
41
42/*
43 * Copy module-related data into the load area, where it can be
44 * used as a directory for loaded modules.
45 *
46 * Module data is presented in a self-describing format.  Each datum
47 * is preceded by a 32-bit identifier and a 32-bit size field.
48 *
49 * Currently, the following data are saved:
50 *
51 * MOD_NAME	(variable)		module name (string)
52 * MOD_TYPE	(variable)		module type (string)
53 * MOD_ARGS	(variable)		module parameters (string)
54 * MOD_ADDR	sizeof(vm_offset_t)	module load address
55 * MOD_SIZE	sizeof(size_t)		module size
56 * MOD_METADATA	(variable)		type-specific metadata
57 */
58#define COPY32(v, a, c) {			\
59    u_int32_t	x = (v);			\
60    if (c)					\
61	i386_copyin(&x, a, sizeof(x));		\
62    a += sizeof(x);				\
63}
64
65#define MOD_STR(t, a, s, c) {			\
66    COPY32(t, a, c);				\
67    COPY32(strlen(s) + 1, a, c);		\
68    if (c)					\
69	i386_copyin(s, a, strlen(s) + 1);	\
70    a += roundup(strlen(s) + 1, sizeof(u_int64_t));\
71}
72
73#define MOD_NAME(a, s, c)	MOD_STR(MODINFO_NAME, a, s, c)
74#define MOD_TYPE(a, s, c)	MOD_STR(MODINFO_TYPE, a, s, c)
75#define MOD_ARGS(a, s, c)	MOD_STR(MODINFO_ARGS, a, s, c)
76
77#define MOD_VAR(t, a, s, c) {			\
78    COPY32(t, a, c);				\
79    COPY32(sizeof(s), a, c);			\
80    if (c)					\
81	i386_copyin(&s, a, sizeof(s));		\
82    a += roundup(sizeof(s), sizeof(u_int64_t));	\
83}
84
85#define MOD_ADDR(a, s, c)	MOD_VAR(MODINFO_ADDR, a, s, c)
86#define MOD_SIZE(a, s, c)	MOD_VAR(MODINFO_SIZE, a, s, c)
87
88#define MOD_METADATA(a, mm, c) {		\
89    COPY32(MODINFO_METADATA | mm->md_type, a, c); \
90    COPY32(mm->md_size, a, c);			\
91    if (c)					\
92	i386_copyin(mm->md_data, a, mm->md_size); \
93    a += roundup(mm->md_size, sizeof(u_int64_t));\
94}
95
96#define MOD_END(a, c) {				\
97    COPY32(MODINFO_END, a, c);			\
98    COPY32(0, a, c);				\
99}
100
101static vm_offset_t
102bi_copymodules64(vm_offset_t addr)
103{
104    struct preloaded_file	*fp;
105    struct file_metadata	*md;
106    int				c;
107    u_int64_t			v;
108
109    c = addr != 0;
110    /* start with the first module on the list, should be the kernel */
111    for (fp = file_findfile(NULL, NULL); fp != NULL; fp = fp->f_next) {
112
113	MOD_NAME(addr, fp->f_name, c);	/* this field must come first */
114	MOD_TYPE(addr, fp->f_type, c);
115	if (fp->f_args)
116	    MOD_ARGS(addr, fp->f_args, c);
117	v = fp->f_addr;
118	MOD_ADDR(addr, v, c);
119	v = fp->f_size;
120	MOD_SIZE(addr, v, c);
121	for (md = fp->f_metadata; md != NULL; md = md->md_next)
122	    if (!(md->md_type & MODINFOMD_NOCOPY))
123		MOD_METADATA(addr, md, c);
124    }
125    MOD_END(addr, c);
126    return(addr);
127}
128
129/*
130 * Check to see if this CPU supports long mode.
131 */
132static int
133bi_checkcpu(void)
134{
135    char *cpu_vendor;
136    int vendor[3];
137    int eflags, regs[4];
138
139    /* Check for presence of "cpuid". */
140    eflags = read_eflags();
141    write_eflags(eflags ^ PSL_ID);
142    if (!((eflags ^ read_eflags()) & PSL_ID))
143	return (0);
144
145    /* Fetch the vendor string. */
146    do_cpuid(0, regs);
147    vendor[0] = regs[1];
148    vendor[1] = regs[3];
149    vendor[2] = regs[2];
150    cpu_vendor = (char *)vendor;
151
152    /* Check for vendors that support AMD features. */
153    if (strncmp(cpu_vendor, "GenuineIntel", 12) != 0 &&
154	strncmp(cpu_vendor, "AuthenticAMD", 12) != 0)
155	return (0);
156
157    /* Has to support AMD features. */
158    do_cpuid(0x80000000, regs);
159    if (!(regs[0] >= 0x80000001))
160	return (0);
161
162    /* Check for long mode. */
163    do_cpuid(0x80000001, regs);
164    return (regs[3] & AMDID_LM);
165}
166
167/*
168 * Load the information expected by an amd64 kernel.
169 *
170 * - The 'boothowto' argument is constructed
171 * - The 'bootdev' argument is constructed
172 * - The 'bootinfo' struct is constructed, and copied into the kernel space.
173 * - The kernel environment is copied into kernel space.
174 * - Module metadata are formatted and placed in kernel space.
175 */
176int
177bi_load64(char *args, vm_offset_t *modulep, vm_offset_t *kernendp)
178{
179    struct preloaded_file	*xp, *kfp;
180    struct i386_devdesc		*rootdev;
181    struct file_metadata	*md;
182    vm_offset_t			addr;
183    u_int64_t			kernend;
184    u_int64_t			envp;
185    vm_offset_t			size;
186    char			*rootdevname;
187    int				howto;
188
189    if (!bi_checkcpu()) {
190	printf("CPU doesn't support long mode\n");
191	return (EINVAL);
192    }
193
194    howto = bi_getboothowto(args);
195
196    /*
197     * Allow the environment variable 'rootdev' to override the supplied device
198     * This should perhaps go to MI code and/or have $rootdev tested/set by
199     * MI code before launching the kernel.
200     */
201    rootdevname = getenv("rootdev");
202    i386_getdev((void **)(&rootdev), rootdevname, NULL);
203    if (rootdev == NULL) {		/* bad $rootdev/$currdev */
204	printf("can't determine root device\n");
205	return(EINVAL);
206    }
207
208    /* Try reading the /etc/fstab file to select the root device */
209    getrootmount(i386_fmtdev((void *)rootdev));
210
211    /* find the last module in the chain */
212    addr = 0;
213    for (xp = file_findfile(NULL, NULL); xp != NULL; xp = xp->f_next) {
214	if (addr < (xp->f_addr + xp->f_size))
215	    addr = xp->f_addr + xp->f_size;
216    }
217    /* pad to a page boundary */
218    addr = roundup(addr, PAGE_SIZE);
219
220    /* copy our environment */
221    envp = addr;
222    addr = bi_copyenv(addr);
223
224    /* pad to a page boundary */
225    addr = roundup(addr, PAGE_SIZE);
226
227    kfp = file_findfile(NULL, "elf kernel");
228    if (kfp == NULL)
229      kfp = file_findfile(NULL, "elf64 kernel");
230    if (kfp == NULL)
231	panic("can't find kernel file");
232    kernend = 0;	/* fill it in later */
233    file_addmetadata(kfp, MODINFOMD_HOWTO, sizeof howto, &howto);
234    file_addmetadata(kfp, MODINFOMD_ENVP, sizeof envp, &envp);
235    file_addmetadata(kfp, MODINFOMD_KERNEND, sizeof kernend, &kernend);
236    bios_addsmapdata(kfp);
237
238    /* Figure out the size and location of the metadata */
239    *modulep = addr;
240    size = bi_copymodules64(0);
241    kernend = roundup(addr + size, PAGE_SIZE);
242    *kernendp = kernend;
243
244    /* patch MODINFOMD_KERNEND */
245    md = file_findmetadata(kfp, MODINFOMD_KERNEND);
246    bcopy(&kernend, md->md_data, sizeof kernend);
247
248    /* copy module list and metadata */
249    (void)bi_copymodules64(addr);
250
251    return(0);
252}
253