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