1 /*
2 * Copyright (C) 2008 Michael Brown <mbrown@fensystems.co.uk>.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation; either version 2 of the
7 * License, or any later version.
8 *
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
17 * 02110-1301, USA.
18 */
19
20 FILE_LICENCE ( GPL2_OR_LATER );
21
22 #include <string.h>
23 #include <errno.h>
24 #include <ipxe/init.h>
25 #include <ipxe/efi/efi.h>
26 #include <ipxe/efi/efi_driver.h>
27 #include <ipxe/efi/Protocol/LoadedImage.h>
28
29 /** Image handle passed to entry point */
30 EFI_HANDLE efi_image_handle;
31
32 /** Loaded image protocol for this image */
33 EFI_LOADED_IMAGE_PROTOCOL *efi_loaded_image;
34
35 /** System table passed to entry point
36 *
37 * We construct the symbol name efi_systab via the PLATFORM macro.
38 * This ensures that the symbol is defined only in EFI builds, and so
39 * prevents EFI code from being incorrectly linked in to a non-EFI
40 * build.
41 */
42 EFI_SYSTEM_TABLE * _C2 ( PLATFORM, _systab );
43
44 /** EFI shutdown is in progress */
45 int efi_shutdown_in_progress;
46
47 /** Event used to signal shutdown */
48 static EFI_EVENT efi_shutdown_event;
49
50 /* Forward declarations */
51 static EFI_STATUS EFIAPI efi_unload ( EFI_HANDLE image_handle );
52
53 /**
54 * Shut down in preparation for booting an OS.
55 *
56 * This hook gets called at ExitBootServices time in order to make
57 * sure that everything is properly shut down before the OS takes
58 * over.
59 */
efi_shutdown_hook(EFI_EVENT event __unused,void * context __unused)60 static EFIAPI void efi_shutdown_hook ( EFI_EVENT event __unused,
61 void *context __unused ) {
62
63 /* Mark shutdown as being in progress, to indicate that large
64 * parts of the system (e.g. timers) are no longer functional.
65 */
66 efi_shutdown_in_progress = 1;
67
68 /* Shut down iPXE */
69 shutdown_boot();
70 }
71
72 /**
73 * Look up EFI configuration table
74 *
75 * @v guid Configuration table GUID
76 * @ret table Configuration table, or NULL
77 */
efi_find_table(EFI_GUID * guid)78 static void * efi_find_table ( EFI_GUID *guid ) {
79 unsigned int i;
80
81 for ( i = 0 ; i < efi_systab->NumberOfTableEntries ; i++ ) {
82 if ( memcmp ( &efi_systab->ConfigurationTable[i].VendorGuid,
83 guid, sizeof ( *guid ) ) == 0 )
84 return efi_systab->ConfigurationTable[i].VendorTable;
85 }
86
87 return NULL;
88 }
89
90 /**
91 * Initialise EFI environment
92 *
93 * @v image_handle Image handle
94 * @v systab System table
95 * @ret efirc EFI return status code
96 */
efi_init(EFI_HANDLE image_handle,EFI_SYSTEM_TABLE * systab)97 EFI_STATUS efi_init ( EFI_HANDLE image_handle,
98 EFI_SYSTEM_TABLE *systab ) {
99 EFI_BOOT_SERVICES *bs;
100 struct efi_protocol *prot;
101 struct efi_config_table *tab;
102 void *loaded_image;
103 EFI_STATUS efirc;
104 int rc;
105
106 /* Store image handle and system table pointer for future use */
107 efi_image_handle = image_handle;
108 efi_systab = systab;
109
110 /* Sanity checks */
111 if ( ! systab ) {
112 efirc = EFI_NOT_AVAILABLE_YET;
113 goto err_sanity;
114 }
115 if ( ! systab->ConOut ) {
116 efirc = EFI_NOT_AVAILABLE_YET;
117 goto err_sanity;
118 }
119 if ( ! systab->BootServices ) {
120 DBGC ( systab, "EFI provided no BootServices entry point\n" );
121 efirc = EFI_NOT_AVAILABLE_YET;
122 goto err_sanity;
123 }
124 if ( ! systab->RuntimeServices ) {
125 DBGC ( systab, "EFI provided no RuntimeServices entry "
126 "point\n" );
127 efirc = EFI_NOT_AVAILABLE_YET;
128 goto err_sanity;
129 }
130 DBGC ( systab, "EFI handle %p systab %p\n", image_handle, systab );
131 bs = systab->BootServices;
132
133 /* Look up used protocols */
134 for_each_table_entry ( prot, EFI_PROTOCOLS ) {
135 if ( ( efirc = bs->LocateProtocol ( &prot->guid, NULL,
136 prot->protocol ) ) == 0 ) {
137 DBGC ( systab, "EFI protocol %s is at %p\n",
138 efi_guid_ntoa ( &prot->guid ),
139 *(prot->protocol) );
140 } else {
141 DBGC ( systab, "EFI does not provide protocol %s\n",
142 efi_guid_ntoa ( &prot->guid ) );
143 /* Fail if protocol is required */
144 if ( prot->required )
145 goto err_missing_protocol;
146 }
147 }
148
149 /* Look up used configuration tables */
150 for_each_table_entry ( tab, EFI_CONFIG_TABLES ) {
151 if ( ( *(tab->table) = efi_find_table ( &tab->guid ) ) ) {
152 DBGC ( systab, "EFI configuration table %s is at %p\n",
153 efi_guid_ntoa ( &tab->guid ), *(tab->table) );
154 } else {
155 DBGC ( systab, "EFI does not provide configuration "
156 "table %s\n", efi_guid_ntoa ( &tab->guid ) );
157 if ( tab->required ) {
158 efirc = EFI_NOT_AVAILABLE_YET;
159 goto err_missing_table;
160 }
161 }
162 }
163
164 /* Get loaded image protocol */
165 if ( ( efirc = bs->OpenProtocol ( image_handle,
166 &efi_loaded_image_protocol_guid,
167 &loaded_image, image_handle, NULL,
168 EFI_OPEN_PROTOCOL_GET_PROTOCOL ) ) != 0 ) {
169 rc = -EEFI ( efirc );
170 DBGC ( systab, "EFI could not get loaded image protocol: %s",
171 strerror ( rc ) );
172 goto err_no_loaded_image;
173 }
174 efi_loaded_image = loaded_image;
175 DBGC ( systab, "EFI image base address %p\n",
176 efi_loaded_image->ImageBase );
177
178 /* EFI is perfectly capable of gracefully shutting down any
179 * loaded devices if it decides to fall back to a legacy boot.
180 * For no particularly comprehensible reason, it doesn't
181 * bother doing so when ExitBootServices() is called.
182 */
183 if ( ( efirc = bs->CreateEvent ( EVT_SIGNAL_EXIT_BOOT_SERVICES,
184 TPL_CALLBACK, efi_shutdown_hook,
185 NULL, &efi_shutdown_event ) ) != 0 ) {
186 rc = -EEFI ( efirc );
187 DBGC ( systab, "EFI could not create ExitBootServices event: "
188 "%s\n", strerror ( rc ) );
189 goto err_create_event;
190 }
191
192 /* Install driver binding protocol */
193 if ( ( rc = efi_driver_install() ) != 0 ) {
194 DBGC ( systab, "EFI could not install driver: %s\n",
195 strerror ( rc ) );
196 efirc = EFIRC ( rc );
197 goto err_driver_install;
198 }
199
200 /* Install image unload method */
201 efi_loaded_image->Unload = efi_unload;
202
203 return 0;
204
205 efi_driver_uninstall();
206 err_driver_install:
207 bs->CloseEvent ( efi_shutdown_event );
208 err_create_event:
209 err_no_loaded_image:
210 err_missing_table:
211 err_missing_protocol:
212 err_sanity:
213 return efirc;
214 }
215
216 /**
217 * Shut down EFI environment
218 *
219 * @v image_handle Image handle
220 */
efi_unload(EFI_HANDLE image_handle __unused)221 static EFI_STATUS EFIAPI efi_unload ( EFI_HANDLE image_handle __unused ) {
222 EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
223 EFI_SYSTEM_TABLE *systab = efi_systab;
224
225 DBGC ( systab, "EFI image unloading\n" );
226
227 /* Shut down */
228 shutdown_exit();
229
230 /* Disconnect any remaining devices */
231 efi_driver_disconnect_all();
232
233 /* Uninstall driver binding protocol */
234 efi_driver_uninstall();
235
236 /* Uninstall exit boot services event */
237 bs->CloseEvent ( efi_shutdown_event );
238
239 DBGC ( systab, "EFI image unloaded\n" );
240
241 return 0;
242 }
243