1 /*-
2 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
3 * Copyright (c) 2014 The FreeBSD Foundation
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 *
27 * $FreeBSD: head/sys/boot/efi/loader/arch/amd64/elf64_freebsd.c 293724 2016-01-12 02:17:39Z smh $
28 */
29
30 #define __ELF_WORD_SIZE 64
31 #include <sys/param.h>
32 #include <sys/exec.h>
33 #include <sys/linker.h>
34 #include <string.h>
35 #include <machine/elf.h>
36 #include <stand.h>
37
38 #include <efi.h>
39 #include <efilib.h>
40
41 #include "bootstrap.h"
42
43 #include "acpi.h"
44
45 #include "loader_efi.h"
46
47 static EFI_GUID acpi_guid = ACPI_TABLE_GUID;
48 static EFI_GUID acpi20_guid = EFI_ACPI_TABLE_GUID;
49
50 extern int bi_load(char *args, vm_offset_t *modulep, vm_offset_t *kernendp);
51
52 static int elf64_exec(struct preloaded_file *amp);
53 static int elf64_obj_exec(struct preloaded_file *amp);
54
55 static struct file_format amd64_elf = { elf64_loadfile, elf64_exec };
56 static struct file_format amd64_elf_obj = { elf64_obj_loadfile, elf64_obj_exec };
57
58 struct file_format *file_formats[] = {
59 &amd64_elf,
60 &amd64_elf_obj,
61 NULL
62 };
63
64 #define PG_V 0x001
65 #define PG_RW 0x002
66 #define PG_U 0x004
67 #define PG_PS 0x080
68
69 typedef u_int64_t p4_entry_t;
70 typedef u_int64_t p3_entry_t;
71 typedef u_int64_t p2_entry_t;
72 static p4_entry_t *PT4;
73 static p3_entry_t *PT3;
74 static p2_entry_t *PT2;
75
76 static void (*trampoline)(uint64_t stack, void *copy_finish, uint64_t kernend,
77 uint64_t modulep, p4_entry_t *pagetable,
78 uint64_t entry);
79
80 extern uintptr_t amd64_tramp;
81 extern uint32_t amd64_tramp_size;
82
83 /*
84 * There is an ELF kernel and one or more ELF modules loaded.
85 * We wish to start executing the kernel image, so make such
86 * preparations as are required, and do so.
87 */
88 static int
elf64_exec(struct preloaded_file * fp)89 elf64_exec(struct preloaded_file *fp)
90 {
91 struct file_metadata *md;
92 Elf_Ehdr *ehdr;
93 vm_offset_t modulep, kernend, trampcode, trampstack;
94 int err, i;
95 ACPI_TABLE_RSDP *rsdp;
96 char buf[24];
97 int revision;
98
99 rsdp = efi_get_table(&acpi20_guid);
100 if (rsdp == NULL) {
101 rsdp = efi_get_table(&acpi_guid);
102 }
103 if (rsdp != NULL) {
104 sprintf(buf, "0x%016llx", (unsigned long long)rsdp);
105 setenv("hint.acpi.0.rsdp", buf, 1);
106 revision = rsdp->Revision;
107 if (revision == 0)
108 revision = 1;
109 sprintf(buf, "%d", revision);
110 setenv("hint.acpi.0.revision", buf, 1);
111 strncpy(buf, rsdp->OemId, sizeof(rsdp->OemId));
112 buf[sizeof(rsdp->OemId)] = '\0';
113 setenv("hint.acpi.0.oem", buf, 1);
114 sprintf(buf, "0x%016x", rsdp->RsdtPhysicalAddress);
115 setenv("hint.acpi.0.rsdt", buf, 1);
116 if (revision >= 2) {
117 /* XXX extended checksum? */
118 sprintf(buf, "0x%016llx",
119 (unsigned long long)rsdp->XsdtPhysicalAddress);
120 setenv("hint.acpi.0.xsdt", buf, 1);
121 sprintf(buf, "%d", rsdp->Length);
122 setenv("hint.acpi.0.xsdt_length", buf, 1);
123 }
124 }
125
126 if ((md = file_findmetadata(fp, MODINFOMD_ELFHDR)) == NULL)
127 return(EFTYPE);
128 ehdr = (Elf_Ehdr *)&(md->md_data);
129
130 trampcode = (vm_offset_t)0x0000000040000000;
131 err = BS->AllocatePages(AllocateMaxAddress, EfiLoaderData, 1,
132 (EFI_PHYSICAL_ADDRESS *)&trampcode);
133 bzero((void *)trampcode, EFI_PAGE_SIZE);
134 trampstack = trampcode + EFI_PAGE_SIZE - 8;
135 bcopy((void *)&amd64_tramp, (void *)trampcode, amd64_tramp_size);
136 trampoline = (void *)trampcode;
137
138 PT4 = (p4_entry_t *)0x0000000040000000;
139 err = BS->AllocatePages(AllocateMaxAddress, EfiLoaderData, 3,
140 (EFI_PHYSICAL_ADDRESS *)&PT4);
141 bzero(PT4, 3 * EFI_PAGE_SIZE);
142
143 PT3 = &PT4[512];
144 PT2 = &PT3[512];
145
146 /*
147 * This is kinda brutal, but every single 1GB VM memory segment points
148 * to the same first 1GB of physical memory. But it is more than
149 * adequate.
150 */
151 for (i = 0; i < 512; i++) {
152 /* Each slot of the L4 pages points to the same L3 page. */
153 PT4[i] = (p4_entry_t)PT3;
154 PT4[i] |= PG_V | PG_RW | PG_U;
155
156 /* Each slot of the L3 pages points to the same L2 page. */
157 PT3[i] = (p3_entry_t)PT2;
158 PT3[i] |= PG_V | PG_RW | PG_U;
159
160 /* The L2 page slots are mapped with 2MB pages for 1GB. */
161 PT2[i] = i * (2 * 1024 * 1024);
162 PT2[i] |= PG_V | PG_RW | PG_PS | PG_U;
163 }
164
165 printf("Start @ 0x%lx ...\n", ehdr->e_entry);
166
167 err = bi_load(fp->f_args, &modulep, &kernend);
168 if (err != 0)
169 return(err);
170
171 dev_cleanup();
172
173 trampoline(trampstack, efi_copy_finish, kernend, modulep, PT4,
174 ehdr->e_entry);
175
176 panic("exec returned");
177 }
178
179 static int
elf64_obj_exec(struct preloaded_file * fp)180 elf64_obj_exec(struct preloaded_file *fp)
181 {
182 return (EFTYPE);
183 }
184