xref: /freebsd/stand/i386/libi386/bootinfo64.c (revision ec965063070e5753c166cf592c9336444b74720a)
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("$FreeBSD$");
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/metadata.h>
37 #include <machine/psl.h>
38 #include <machine/specialreg.h>
39 #include "bootstrap.h"
40 #include "modinfo.h"
41 #include "libi386.h"
42 #include "btxv86.h"
43 
44 #ifdef LOADER_GELI_SUPPORT
45 #include "geliboot.h"
46 #endif
47 
48 /*
49  * Check to see if this CPU supports long mode.
50  */
51 static int
52 bi_checkcpu(void)
53 {
54     char *cpu_vendor;
55     int vendor[3];
56     int eflags;
57     unsigned int regs[4];
58 
59     /* Check for presence of "cpuid". */
60     eflags = read_eflags();
61     write_eflags(eflags ^ PSL_ID);
62     if (!((eflags ^ read_eflags()) & PSL_ID))
63 	return (0);
64 
65     /* Fetch the vendor string. */
66     do_cpuid(0, regs);
67     vendor[0] = regs[1];
68     vendor[1] = regs[3];
69     vendor[2] = regs[2];
70     cpu_vendor = (char *)vendor;
71 
72     /* Check for vendors that support AMD features. */
73     if (strncmp(cpu_vendor, INTEL_VENDOR_ID, 12) != 0 &&
74 	strncmp(cpu_vendor, AMD_VENDOR_ID, 12) != 0 &&
75 	strncmp(cpu_vendor, HYGON_VENDOR_ID, 12) != 0 &&
76 	strncmp(cpu_vendor, CENTAUR_VENDOR_ID, 12) != 0)
77 	return (0);
78 
79     /* Has to support AMD features. */
80     do_cpuid(0x80000000, regs);
81     if (!(regs[0] >= 0x80000001))
82 	return (0);
83 
84     /* Check for long mode. */
85     do_cpuid(0x80000001, regs);
86     return (regs[3] & AMDID_LM);
87 }
88 
89 /*
90  * Load the information expected by an amd64 kernel.
91  *
92  * - The 'boothowto' argument is constructed
93  * - The 'bootdev' argument is constructed
94  * - The 'bootinfo' struct is constructed, and copied into the kernel space.
95  * - The kernel environment is copied into kernel space.
96  * - Module metadata are formatted and placed in kernel space.
97  */
98 int
99 bi_load64(char *args, vm_offset_t *modulep,
100     vm_offset_t *kernendp, int add_smap)
101 {
102     struct preloaded_file	*xp, *kfp;
103     struct i386_devdesc		*rootdev;
104     struct file_metadata	*md;
105     uint64_t			kernend;
106     uint64_t			envp;
107     uint64_t			module;
108     uint64_t			addr;
109     vm_offset_t			size;
110     char			*rootdevname;
111     int				howto;
112 
113     if (!bi_checkcpu()) {
114 	printf("CPU doesn't support long mode\n");
115 	return (EINVAL);
116     }
117 
118     howto = bi_getboothowto(args);
119 
120     /*
121      * Allow the environment variable 'rootdev' to override the supplied device
122      * This should perhaps go to MI code and/or have $rootdev tested/set by
123      * MI code before launching the kernel.
124      */
125     rootdevname = getenv("rootdev");
126     i386_getdev((void **)(&rootdev), rootdevname, NULL);
127     if (rootdev == NULL) {		/* bad $rootdev/$currdev */
128 	printf("can't determine root device\n");
129 	return(EINVAL);
130     }
131 
132     /* Try reading the /etc/fstab file to select the root device */
133     getrootmount(devformat(&rootdev->dd));
134 
135     addr = 0;
136     /* find the last module in the chain */
137     for (xp = file_findfile(NULL, NULL); xp != NULL; xp = xp->f_next) {
138         if (addr < (xp->f_addr + xp->f_size))
139             addr = xp->f_addr + xp->f_size;
140     }
141     /* pad to a page boundary */
142     addr = roundup(addr, PAGE_SIZE);
143 
144     addr = build_font_module(addr);
145 
146     /* place the metadata before anything */
147     module = *modulep = addr;
148 
149     kfp = file_findfile(NULL, "elf kernel");
150     if (kfp == NULL)
151       kfp = file_findfile(NULL, "elf64 kernel");
152     if (kfp == NULL)
153 	panic("can't find kernel file");
154     kernend = 0;	/* fill it in later */
155     file_addmetadata(kfp, MODINFOMD_HOWTO, sizeof howto, &howto);
156     file_addmetadata(kfp, MODINFOMD_ENVP, sizeof envp, &envp);
157     file_addmetadata(kfp, MODINFOMD_KERNEND, sizeof kernend, &kernend);
158     file_addmetadata(kfp, MODINFOMD_MODULEP, sizeof module, &module);
159     if (add_smap != 0)
160         bios_addsmapdata(kfp);
161 #ifdef LOADER_GELI_SUPPORT
162     geli_export_key_metadata(kfp);
163 #endif
164     bi_load_vbe_data(kfp);
165 
166     size = md_copymodules(0, true);
167 
168     /* copy our environment */
169     envp = roundup(addr + size, PAGE_SIZE);
170     addr = md_copyenv(envp);
171 
172     /* set kernend */
173     kernend = roundup(addr, PAGE_SIZE);
174     *kernendp = kernend;
175 
176     /* patch MODINFOMD_KERNEND */
177     md = file_findmetadata(kfp, MODINFOMD_KERNEND);
178     bcopy(&kernend, md->md_data, sizeof kernend);
179 
180     /* patch MODINFOMD_ENVP */
181     md = file_findmetadata(kfp, MODINFOMD_ENVP);
182     bcopy(&envp, md->md_data, sizeof envp);
183 
184     /* copy module list and metadata */
185     (void)md_copymodules(*modulep, true);
186 
187     return(0);
188 }
189