aboutsummaryrefslogtreecommitdiff
path: root/src/interface/efi/efi_init.c
blob: 5eb10135025752c1c325a04e9c7fa626434ba039 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
/*
 * Copyright (C) 2008 Michael Brown <mbrown@fensystems.co.uk>.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation; either version 2 of the
 * License, or any later version.
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
 * 02110-1301, USA.
 */

FILE_LICENCE ( GPL2_OR_LATER );

#include <string.h>
#include <errno.h>
#include <ipxe/efi/efi.h>
#include <ipxe/efi/efi_driver.h>
#include <ipxe/efi/Protocol/LoadedImage.h>
#include <ipxe/efi/Protocol/DevicePath.h>
#include <ipxe/uuid.h>
#include <ipxe/init.h>

/** Image handle passed to entry point */
EFI_HANDLE efi_image_handle;

/** Loaded image protocol for this image */
EFI_LOADED_IMAGE_PROTOCOL *efi_loaded_image;

/** System table passed to entry point */
EFI_SYSTEM_TABLE *efi_systab;

/** EFI loaded image protocol GUID */
static EFI_GUID efi_loaded_image_protocol_guid
	= EFI_LOADED_IMAGE_PROTOCOL_GUID;

/** Event used to signal shutdown */
static EFI_EVENT efi_shutdown_event;

/* Forward declarations */
static EFI_STATUS EFIAPI efi_unload ( EFI_HANDLE image_handle );

/**
 * Check to see if driver supports a device
 *
 * @v driver		EFI driver
 * @v device		EFI device
 * @v child		Path to child device, if any
 * @ret efirc		EFI status code
 */
static EFI_STATUS EFIAPI
efi_image_supported ( EFI_DRIVER_BINDING_PROTOCOL *driver __unused,
		    EFI_HANDLE device __unused,
		    EFI_DEVICE_PATH_PROTOCOL *child __unused ) {

	return EFI_UNSUPPORTED;
}

/**
 * Attach driver to device
 *
 * @v driver		EFI driver
 * @v device		EFI device
 * @v child		Path to child device, if any
 * @ret efirc		EFI status code
 */
static EFI_STATUS EFIAPI
efi_image_start ( EFI_DRIVER_BINDING_PROTOCOL *driver __unused,
		EFI_HANDLE device __unused,
		EFI_DEVICE_PATH_PROTOCOL *child __unused ) {

	return EFI_UNSUPPORTED;
}

/**
 * Detach driver from device
 *
 * @v driver		EFI driver
 * @v device		EFI device
 * @v pci		PCI device
 * @v num_children	Number of child devices
 * @v children		List of child devices
 * @ret efirc		EFI status code
 */
static EFI_STATUS EFIAPI
efi_image_stop ( EFI_DRIVER_BINDING_PROTOCOL *driver __unused,
	       EFI_HANDLE device __unused, UINTN num_children __unused,
	       EFI_HANDLE *children __unused ) {

	return EFI_UNSUPPORTED;
}

/** EFI loaded image driver */
static struct efi_driver efi_image_driver =
	EFI_DRIVER_INIT ( NULL, efi_image_supported, efi_image_start,
			  efi_image_stop );

/**
 * Shut down in preparation for booting an OS.
 *
 * This hook gets called at ExitBootServices time in order to make
 * sure that everything is properly shut down before the OS takes
 * over.
 */
static EFIAPI void efi_shutdown_hook ( EFI_EVENT event __unused,
				       void *context __unused ) {
	shutdown_boot();
}

/**
 * Look up EFI configuration table
 *
 * @v guid		Configuration table GUID
 * @ret table		Configuration table, or NULL
 */
static void * efi_find_table ( EFI_GUID *guid ) {
	unsigned int i;

	for ( i = 0 ; i < efi_systab->NumberOfTableEntries ; i++ ) {
		if ( memcmp ( &efi_systab->ConfigurationTable[i].VendorGuid,
			      guid, sizeof ( *guid ) ) == 0 )
			return efi_systab->ConfigurationTable[i].VendorTable;
	}

	return NULL;
}

/**
 * Initialise EFI environment
 *
 * @v image_handle	Image handle
 * @v systab		System table
 * @ret efirc		EFI return status code
 */
EFI_STATUS efi_init ( EFI_HANDLE image_handle,
		      EFI_SYSTEM_TABLE *systab ) {
	EFI_BOOT_SERVICES *bs;
	struct efi_protocol *prot;
	struct efi_config_table *tab;
	void *loaded_image;
	EFI_STATUS efirc;
	int rc;

	/* Store image handle and system table pointer for future use */
	efi_image_handle = image_handle;
	efi_systab = systab;

	/* Sanity checks */
	if ( ! systab )
		return EFI_NOT_AVAILABLE_YET;
	if ( ! systab->ConOut )
		return EFI_NOT_AVAILABLE_YET;
	if ( ! systab->BootServices ) {
		DBGC ( systab, "EFI provided no BootServices entry point\n" );
		return EFI_NOT_AVAILABLE_YET;
	}
	if ( ! systab->RuntimeServices ) {
		DBGC ( systab, "EFI provided no RuntimeServices entry "
		       "point\n" );
		return EFI_NOT_AVAILABLE_YET;
	}
	DBGC ( systab, "EFI handle %p systab %p\n", image_handle, systab );
	bs = systab->BootServices;

	/* Look up used protocols */
	for_each_table_entry ( prot, EFI_PROTOCOLS ) {
		if ( ( efirc = bs->LocateProtocol ( &prot->guid, NULL,
						    prot->protocol ) ) == 0 ) {
			DBGC ( systab, "EFI protocol %s is at %p\n",
			       efi_guid_ntoa ( &prot->guid ),
			       *(prot->protocol) );
		} else {
			DBGC ( systab, "EFI does not provide protocol %s\n",
			       efi_guid_ntoa ( &prot->guid ) );
			/* Fail if protocol is required */
			if ( prot->required )
				return efirc;
		}
	}

	/* Look up used configuration tables */
	for_each_table_entry ( tab, EFI_CONFIG_TABLES ) {
		if ( ( *(tab->table) = efi_find_table ( &tab->guid ) ) ) {
			DBGC ( systab, "EFI configuration table %s is at %p\n",
			       efi_guid_ntoa ( &tab->guid ), *(tab->table) );
		} else {
			DBGC ( systab, "EFI does not provide configuration "
			       "table %s\n", efi_guid_ntoa ( &tab->guid ) );
			if ( tab->required )
				return EFI_NOT_AVAILABLE_YET;
		}
	}

	/* Get loaded image protocol */
	if ( ( efirc = bs->OpenProtocol ( image_handle,
				&efi_loaded_image_protocol_guid,
				&loaded_image, image_handle, NULL,
				EFI_OPEN_PROTOCOL_GET_PROTOCOL ) ) != 0 ) {
		rc = -EEFI ( efirc );
		DBGC ( systab, "EFI could not get loaded image protocol: %s",
		       strerror ( rc ) );
		return efirc;
	}
	efi_loaded_image = loaded_image;
	DBGC ( systab, "EFI image base address %p\n",
	       efi_loaded_image->ImageBase );

	/* EFI is perfectly capable of gracefully shutting down any
	 * loaded devices if it decides to fall back to a legacy boot.
	 * For no particularly comprehensible reason, it doesn't
	 * bother doing so when ExitBootServices() is called.
	 */
	if ( ( efirc = bs->CreateEvent ( EVT_SIGNAL_EXIT_BOOT_SERVICES,
					 TPL_CALLBACK, efi_shutdown_hook,
					 NULL, &efi_shutdown_event ) ) != 0 ) {
		rc = -EEFI ( efirc );
		DBGC ( systab, "EFI could not create ExitBootServices event: "
		       "%s\n", strerror ( rc ) );
		return efirc;
	}

	/* Install an EFI driver on the image handle, to allow the
	 * driver to be subsequently unloaded.
	 */
	efi_image_driver.driver.DriverBindingHandle = image_handle;
	if ( ( rc = efi_driver_install ( &efi_image_driver ) ) != 0 ) {
		DBGC ( systab, "EFI could not install loaded image driver: "
		       "%s\n", strerror ( rc ) );
		return EFIRC ( rc );
	}

	/* Install image unload method */
	efi_loaded_image->Unload = efi_unload;

	return 0;
}

/**
 * Shut down EFI environment
 *
 * @v image_handle	Image handle
 */
static EFI_STATUS EFIAPI efi_unload ( EFI_HANDLE image_handle __unused ) {
	EFI_BOOT_SERVICES *bs = efi_systab->BootServices;
	EFI_SYSTEM_TABLE *systab = efi_systab;

	DBGC ( systab, "EFI image unloading\n" );

	/* Shut down */
	shutdown_exit();

	/* Uninstall exit boot services event */
	bs->CloseEvent ( efi_shutdown_event );

	/* Uninstall loaded image driver */
	efi_driver_uninstall ( &efi_image_driver );

	DBGC ( systab, "EFI image unloaded\n" );

	return 0;
}