src/interface/efi/efi_init.c

   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., 675 Mass Ave, Cambridge, MA 02139, USA.
  17  */
  18
  19 FILE_LICENCE ( GPL2_OR_LATER );
  20
  21 #include <string.h>
  22 #include <gpxe/efi/efi.h>
  23 #include <gpxe/efi/Protocol/LoadedImage.h>
  24 #include <gpxe/uuid.h>
  25
  26 /** Image handle passed to entry point */
  27 EFI_HANDLE efi_image_handle;
  28
  29 /** Loaded image protocol for this image */
  30 EFI_LOADED_IMAGE_PROTOCOL *efi_loaded_image;
  31
  32 /** System table passed to entry point */
  33 EFI_SYSTEM_TABLE *efi_systab;
  34
  35 /** EFI loaded image protocol GUID */
  36 static EFI_GUID efi_loaded_image_protocol_guid
  37         = EFI_LOADED_IMAGE_PROTOCOL_GUID;
  38
  39 /**
  40  * Look up EFI configuration table
  41  *
  42  * @v guid              Configuration table GUID
  43  * @ret table           Configuration table, or NULL
  44  */
  45 static void * efi_find_table ( EFI_GUID *guid ) {
  46         unsigned int i;
  47
  48         for ( i = 0 ; i < efi_systab->NumberOfTableEntries ; i++ ) {
  49                 if ( memcmp ( &efi_systab->ConfigurationTable[i].VendorGuid,
  50                               guid, sizeof ( *guid ) ) == 0 )
  51                         return efi_systab->ConfigurationTable[i].VendorTable;
  52         }
  53
  54         return NULL;
  55 }
  56
  57 /**
  58  * Initialise EFI environment
  59  *
  60  * @v image_handle      Image handle
  61  * @v systab            System table
  62  * @ret efirc           EFI return status code
  63  */
  64 EFI_STATUS efi_init ( EFI_HANDLE image_handle,
  65                       EFI_SYSTEM_TABLE *systab ) {
  66         EFI_BOOT_SERVICES *bs;
  67         struct efi_protocol *prot;
  68         struct efi_config_table *tab;
  69         EFI_STATUS efirc;
  70         void *loaded_image;
  71
  72         /* Store image handle and system table pointer for future use */
  73         efi_image_handle = image_handle;
  74         efi_systab = systab;
  75
  76         /* Sanity checks */
  77         if ( ! systab )
  78                 return EFI_NOT_AVAILABLE_YET;
  79         if ( ! systab->ConOut )
  80                 return EFI_NOT_AVAILABLE_YET;
  81         if ( ! systab->BootServices ) {
  82                 DBGC ( systab, "EFI provided no BootServices entry point\n" );
  83                 return EFI_NOT_AVAILABLE_YET;
  84         }
  85         if ( ! systab->RuntimeServices ) {
  86                 DBGC ( systab, "EFI provided no RuntimeServices entry "
  87                        "point\n" );
  88                 return EFI_NOT_AVAILABLE_YET;
  89         }
  90         DBGC ( systab, "EFI handle %p systab %p\n", image_handle, systab );
  91
  92         bs = systab->BootServices;
  93         efirc = bs->OpenProtocol ( image_handle,
  94                                    &efi_loaded_image_protocol_guid,
  95                                    &loaded_image, image_handle, NULL,
  96                                    EFI_OPEN_PROTOCOL_GET_PROTOCOL );
  97         if ( efirc ) {
  98            DBGC ( systab, "Could not get loaded image protocol" );
  99            return efirc;
 100         }
 101
 102         efi_loaded_image = loaded_image;
 103         DBG ( "Image base address = %p\n", efi_loaded_image->ImageBase );
 104
 105         /* Look up used protocols */
 106         for_each_table_entry ( prot, EFI_PROTOCOLS ) {
 107                 if ( ( efirc = bs->LocateProtocol ( &prot->u.guid, NULL,
 108                                                     prot->protocol ) ) == 0 ) {
 109                         DBGC ( systab, "EFI protocol %s is at %p\n",
 110                                uuid_ntoa ( &prot->u.uuid ), *(prot->protocol));
 111                 } else {
 112                         DBGC ( systab, "EFI does not provide protocol %s\n",
 113                                uuid_ntoa ( &prot->u.uuid ) );
 114                         /* All protocols are required */
 115                         return efirc;
 116                 }
 117         }
 118
 119         /* Look up used configuration tables */
 120         for_each_table_entry ( tab, EFI_CONFIG_TABLES ) {
 121                 if ( ( *(tab->table) = efi_find_table ( &tab->u.guid ) ) ) {
 122                         DBGC ( systab, "EFI configuration table %s is at %p\n",
 123                                uuid_ntoa ( &tab->u.uuid ), *(tab->table) );
 124                 } else {
 125                         DBGC ( systab, "EFI does not provide configuration "
 126                                "table %s\n", uuid_ntoa ( &tab->u.uuid ) );
 127                         if ( tab->required )
 128                                 return EFI_NOT_AVAILABLE_YET;
 129                 }
 130         }
 131
 132         return 0;
 133 }