xref: /freebsd/stand/i386/libi386/bootinfo64.c (revision 734e82fe33aa764367791a7d603b383996c6b40b)
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 #include <stand.h>
29 #include <sys/param.h>
30 #include <sys/reboot.h>
31 #include <sys/linker.h>
32 #include <machine/bootinfo.h>
33 #include <machine/cpufunc.h>
34 #include <machine/metadata.h>
35 #include <machine/psl.h>
36 #include <machine/specialreg.h>
37 #include "bootstrap.h"
38 #include "modinfo.h"
39 #include "libi386.h"
40 #include "btxv86.h"
41 
42 #ifdef LOADER_GELI_SUPPORT
43 #include "geliboot.h"
44 #endif
45 
46 /*
47  * Check to see if this CPU supports long mode.
48  */
49 static int
50 bi_checkcpu(void)
51 {
52     char *cpu_vendor;
53     int vendor[3];
54     int eflags;
55     unsigned int regs[4];
56 
57     /* Check for presence of "cpuid". */
58     eflags = read_eflags();
59     write_eflags(eflags ^ PSL_ID);
60     if (!((eflags ^ read_eflags()) & PSL_ID))
61 	return (0);
62 
63     /* Fetch the vendor string. */
64     do_cpuid(0, regs);
65     vendor[0] = regs[1];
66     vendor[1] = regs[3];
67     vendor[2] = regs[2];
68     cpu_vendor = (char *)vendor;
69 
70     /* Check for vendors that support AMD features. */
71     if (strncmp(cpu_vendor, INTEL_VENDOR_ID, 12) != 0 &&
72 	strncmp(cpu_vendor, AMD_VENDOR_ID, 12) != 0 &&
73 	strncmp(cpu_vendor, HYGON_VENDOR_ID, 12) != 0 &&
74 	strncmp(cpu_vendor, CENTAUR_VENDOR_ID, 12) != 0)
75 	return (0);
76 
77     /* Has to support AMD features. */
78     do_cpuid(0x80000000, regs);
79     if (!(regs[0] >= 0x80000001))
80 	return (0);
81 
82     /* Check for long mode. */
83     do_cpuid(0x80000001, regs);
84     return (regs[3] & AMDID_LM);
85 }
86 
87 /*
88  * Load the information expected by an amd64 kernel.
89  *
90  * - The 'boothowto' argument is constructed
91  * - The 'bootdev' argument is constructed
92  * - The 'bootinfo' struct is constructed, and copied into the kernel space.
93  * - The kernel environment is copied into kernel space.
94  * - Module metadata are formatted and placed in kernel space.
95  */
96 int
97 bi_load64(char *args, vm_offset_t *modulep,
98     vm_offset_t *kernendp, int add_smap)
99 {
100     struct preloaded_file	*xp, *kfp;
101     struct i386_devdesc		*rootdev;
102     struct file_metadata	*md;
103     uint64_t			kernend;
104     uint64_t			envp;
105     uint64_t			module;
106     uint64_t			addr;
107     vm_offset_t			size;
108     char			*rootdevname;
109     int				howto;
110 
111     if (!bi_checkcpu()) {
112 	printf("CPU doesn't support long mode\n");
113 	return (EINVAL);
114     }
115 
116     howto = bi_getboothowto(args);
117 
118     /*
119      * Allow the environment variable 'rootdev' to override the supplied device
120      * This should perhaps go to MI code and/or have $rootdev tested/set by
121      * MI code before launching the kernel.
122      */
123     rootdevname = getenv("rootdev");
124     i386_getdev((void **)(&rootdev), rootdevname, NULL);
125     if (rootdev == NULL) {		/* bad $rootdev/$currdev */
126 	printf("can't determine root device\n");
127 	return(EINVAL);
128     }
129 
130     /* Try reading the /etc/fstab file to select the root device */
131     getrootmount(devformat(&rootdev->dd));
132 
133     addr = 0;
134     /* find the last module in the chain */
135     for (xp = file_findfile(NULL, NULL); xp != NULL; xp = xp->f_next) {
136         if (addr < (xp->f_addr + xp->f_size))
137             addr = xp->f_addr + xp->f_size;
138     }
139     /* pad to a page boundary */
140     addr = roundup(addr, PAGE_SIZE);
141 
142     addr = build_font_module(addr);
143 
144     /* place the metadata before anything */
145     module = *modulep = addr;
146 
147     kfp = file_findfile(NULL, "elf kernel");
148     if (kfp == NULL)
149       kfp = file_findfile(NULL, "elf64 kernel");
150     if (kfp == NULL)
151 	panic("can't find kernel file");
152     kernend = 0;	/* fill it in later */
153     file_addmetadata(kfp, MODINFOMD_HOWTO, sizeof howto, &howto);
154     file_addmetadata(kfp, MODINFOMD_ENVP, sizeof envp, &envp);
155     file_addmetadata(kfp, MODINFOMD_KERNEND, sizeof kernend, &kernend);
156     file_addmetadata(kfp, MODINFOMD_MODULEP, sizeof module, &module);
157     if (add_smap != 0)
158         bios_addsmapdata(kfp);
159 #ifdef LOADER_GELI_SUPPORT
160     geli_export_key_metadata(kfp);
161 #endif
162     bi_load_vbe_data(kfp);
163 
164     size = md_copymodules(0, true);
165 
166     /* copy our environment */
167     envp = roundup(addr + size, PAGE_SIZE);
168     addr = md_copyenv(envp);
169 
170     /* set kernend */
171     kernend = roundup(addr, PAGE_SIZE);
172     *kernendp = kernend;
173 
174     /* patch MODINFOMD_KERNEND */
175     md = file_findmetadata(kfp, MODINFOMD_KERNEND);
176     bcopy(&kernend, md->md_data, sizeof kernend);
177 
178     /* patch MODINFOMD_ENVP */
179     md = file_findmetadata(kfp, MODINFOMD_ENVP);
180     bcopy(&envp, md->md_data, sizeof envp);
181 
182     /* copy module list and metadata */
183     (void)md_copymodules(*modulep, true);
184 
185     return(0);
186 }
187