xref: /titanic_52/usr/src/boot/sys/boot/i386/libi386/bootinfo64.c (revision 4a5d661a82b942b6538acd26209d959ce98b593a)
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 
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/metadata.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 
101 static vm_offset_t
102 bi_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  */
132 int
133 bi_checkcpu(void)
134 {
135     char *cpu_vendor;
136     int vendor[3];
137     int eflags;
138     unsigned int regs[4];
139 
140     /* Check for presence of "cpuid". */
141     eflags = read_eflags();
142     write_eflags(eflags ^ PSL_ID);
143     if (!((eflags ^ read_eflags()) & PSL_ID))
144 	return (0);
145 
146     /* Fetch the vendor string. */
147     do_cpuid(0, regs);
148     vendor[0] = regs[1];
149     vendor[1] = regs[3];
150     vendor[2] = regs[2];
151     cpu_vendor = (char *)vendor;
152 
153     /* Check for vendors that support AMD features. */
154     if (strncmp(cpu_vendor, INTEL_VENDOR_ID, 12) != 0 &&
155 	strncmp(cpu_vendor, AMD_VENDOR_ID, 12) != 0 &&
156 	strncmp(cpu_vendor, CENTAUR_VENDOR_ID, 12) != 0)
157 	return (0);
158 
159     /* Has to support AMD features. */
160     do_cpuid(0x80000000, regs);
161     if (!(regs[0] >= 0x80000001))
162 	return (0);
163 
164     /* Check for long mode. */
165     do_cpuid(0x80000001, regs);
166     return (regs[3] & AMDID_LM);
167 }
168 
169 /*
170  * Load the information expected by an amd64 kernel.
171  *
172  * - The 'boothowto' argument is constructed
173  * - The 'bootdev' argument is constructed
174  * - The 'bootinfo' struct is constructed, and copied into the kernel space.
175  * - The kernel environment is copied into kernel space.
176  * - Module metadata are formatted and placed in kernel space.
177  */
178 int
179 bi_load64(char *args, vm_offset_t addr, vm_offset_t *modulep,
180     vm_offset_t *kernendp, int add_smap)
181 {
182     struct preloaded_file	*xp, *kfp;
183     struct i386_devdesc		*rootdev;
184     struct file_metadata	*md;
185     u_int64_t			kernend;
186     u_int64_t			envp;
187     u_int64_t			module;
188     vm_offset_t			size;
189     char			*rootdevname;
190     int				howto;
191 
192     if (!bi_checkcpu()) {
193 	printf("CPU doesn't support long mode\n");
194 	return (EINVAL);
195     }
196 
197     howto = bi_getboothowto(args);
198 
199     /*
200      * Allow the environment variable 'rootdev' to override the supplied device
201      * This should perhaps go to MI code and/or have $rootdev tested/set by
202      * MI code before launching the kernel.
203      */
204     rootdevname = getenv("rootdev");
205     i386_getdev((void **)(&rootdev), rootdevname, NULL);
206     if (rootdev == NULL) {		/* bad $rootdev/$currdev */
207 	printf("can't determine root device\n");
208 	return(EINVAL);
209     }
210 
211     /* Try reading the /etc/fstab file to select the root device */
212     getrootmount(i386_fmtdev((void *)rootdev));
213 
214     if (addr == 0) {
215         /* find the last module in the chain */
216         for (xp = file_findfile(NULL, NULL); xp != NULL; xp = xp->f_next) {
217             if (addr < (xp->f_addr + xp->f_size))
218                 addr = xp->f_addr + xp->f_size;
219         }
220     }
221     /* pad to a page boundary */
222     addr = roundup(addr, PAGE_SIZE);
223 
224     /* place the metadata before anything */
225     module = *modulep = addr;
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     file_addmetadata(kfp, MODINFOMD_MODULEP, sizeof module, &module);
237     if (add_smap != 0)
238         bios_addsmapdata(kfp);
239 
240     size = bi_copymodules64(0);
241 
242     /* copy our environment */
243     envp = roundup(addr + size, PAGE_SIZE);
244     addr = bi_copyenv(envp);
245 
246     /* set kernend */
247     kernend = roundup(addr, PAGE_SIZE);
248     *kernendp = kernend;
249 
250     /* patch MODINFOMD_KERNEND */
251     md = file_findmetadata(kfp, MODINFOMD_KERNEND);
252     bcopy(&kernend, md->md_data, sizeof kernend);
253 
254     /* patch MODINFOMD_ENVP */
255     md = file_findmetadata(kfp, MODINFOMD_ENVP);
256     bcopy(&envp, md->md_data, sizeof envp);
257 
258     /* copy module list and metadata */
259     (void)bi_copymodules64(*modulep);
260 
261     return(0);
262 }
263