xref: /dragonfly/stand/boot/pc32/libi386/bootinfo64.c (revision 479ab7f0492f2a51b48e8537e4f1dc686fc6014b)
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: src/sys/boot/i386/libi386/bootinfo64.c,v 1.36 2003/08/25 23:28:31 obrien Exp $
27  */
28 
29 #include <stand.h>
30 #include <sys/param.h>
31 #include <sys/reboot.h>
32 #include <sys/linker.h>
33 #include <machine/bootinfo.h>
34 #include <machine/cpufunc.h>
35 #include <machine/psl.h>
36 #include <machine/specialreg.h>
37 #include "bootstrap.h"
38 #include "libi386.h"
39 #include "btxv86.h"
40 
41 /*
42  * Copy module-related data into the load area, where it can be
43  * used as a directory for loaded modules.
44  *
45  * Module data is presented in a self-describing format.  Each datum
46  * is preceded by a 32-bit identifier and a 32-bit size field.
47  *
48  * Currently, the following data are saved:
49  *
50  * MOD_NAME         (variable)                    module name (string)
51  * MOD_TYPE         (variable)                    module type (string)
52  * MOD_ARGS         (variable)                    module parameters (string)
53  * MOD_ADDR         sizeof(vm_offset_t) module load address
54  * MOD_SIZE         sizeof(size_t)                module size
55  * MOD_METADATA     (variable)                    type-specific metadata
56  */
57 #define COPY32(v, a, c) {                         \
58     u_int32_t       x = (v);                      \
59     if (c)                                                  \
60           i386_copyin(&x, a, sizeof(x));                    \
61     a += sizeof(x);                               \
62 }
63 
64 #define MOD_STR(t, a, s, c) {                     \
65     COPY32(t, a, c);                                        \
66     COPY32(strlen(s) + 1, a, c);                  \
67     if (c)                                                  \
68           i386_copyin(s, a, strlen(s) + 1);       \
69     a += roundup(strlen(s) + 1, sizeof(u_int64_t));\
70 }
71 
72 #define MOD_NAME(a, s, c)     MOD_STR(MODINFO_NAME, a, s, c)
73 #define MOD_TYPE(a, s, c)     MOD_STR(MODINFO_TYPE, a, s, c)
74 #define MOD_ARGS(a, s, c)     MOD_STR(MODINFO_ARGS, a, s, c)
75 
76 #define MOD_VAR(t, a, s, c) {                     \
77     COPY32(t, a, c);                                        \
78     COPY32(sizeof(s), a, c);                      \
79     if (c)                                                  \
80           i386_copyin(&s, a, sizeof(s));                    \
81     a += roundup(sizeof(s), sizeof(u_int64_t));   \
82 }
83 
84 #define MOD_ADDR(a, s, c)     MOD_VAR(MODINFO_ADDR, a, s, c)
85 #define MOD_SIZE(a, s, c)     MOD_VAR(MODINFO_SIZE, a, s, c)
86 
87 #define MOD_METADATA(a, mm, c) {                  \
88     COPY32(MODINFO_METADATA | mm->md_type, a, c); \
89     COPY32(mm->md_size, a, c);                              \
90     if (c)                                                  \
91           i386_copyin(mm->md_data, a, mm->md_size); \
92     a += roundup(mm->md_size, sizeof(u_int64_t));\
93 }
94 
95 #define MOD_END(a, c) {                                     \
96     COPY32(MODINFO_END, a, c);                              \
97     COPY32(0, a, c);                                        \
98 }
99 
100 static vm_offset_t
bi_copymodules64(vm_offset_t addr)101 bi_copymodules64(vm_offset_t addr)
102 {
103     struct preloaded_file     *fp;
104     struct file_metadata      *md;
105     int                                 c;
106     u_int64_t                           v;
107 
108     c = addr != 0;
109     /* start with the first module on the list, should be the kernel */
110     for (fp = file_findfile(NULL, NULL); fp != NULL; fp = fp->f_next) {
111 
112           MOD_NAME(addr, fp->f_name, c);          /* this field must come first */
113           MOD_TYPE(addr, fp->f_type, c);
114           if (fp->f_args)
115               MOD_ARGS(addr, fp->f_args, c);
116           v = fp->f_addr;
117           MOD_ADDR(addr, v, c);
118           v = fp->f_size;
119           MOD_SIZE(addr, v, c);
120           for (md = fp->f_metadata; md != NULL; md = md->md_next)
121               if (!(md->md_type & MODINFOMD_NOCOPY))
122                     MOD_METADATA(addr, md, c);
123     }
124     MOD_END(addr, c);
125     return(addr);
126 }
127 
128 /*
129  * Check to see if this CPU supports long mode.
130  */
131 static int
bi_checkcpu(void)132 bi_checkcpu(void)
133 {
134     char *cpu_vendor;
135     int vendor[3];
136     int eflags, regs[4];
137 
138     /* Check for presence of "cpuid". */
139     eflags = read_eflags();
140     write_eflags(eflags ^ PSL_ID);
141     if (!((eflags ^ read_eflags()) & PSL_ID))
142           return (0);
143 
144     /* Fetch the vendor string. */
145     do_cpuid(0, regs);
146     vendor[0] = regs[1];
147     vendor[1] = regs[3];
148     vendor[2] = regs[2];
149     cpu_vendor = (char *)vendor;
150 
151     /* Check for vendors that support AMD features. */
152     if (strncmp(cpu_vendor, "GenuineIntel", 12) != 0 &&
153           strncmp(cpu_vendor, "AuthenticAMD", 12) != 0 &&
154           strncmp(cpu_vendor, "CentaurHauls", 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  */
176 int
bi_load64(char * args,vm_offset_t * modulep,vm_offset_t * kernendp)177 bi_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(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