1/* 2 * Copyright (c) 2006-2007 Apple Inc. All Rights Reserved. 3 * 4 * @APPLE_LICENSE_HEADER_START@ 5 * 6 * This file contains Original Code and/or Modifications of Original Code 7 * as defined in and that are subject to the Apple Public Source License 8 * Version 2.0 (the 'License'). You may not use this file except in 9 * compliance with the License. Please obtain a copy of the License at 10 * http://www.opensource.apple.com/apsl/ and read it before using this 11 * file. 12 * 13 * The Original Code and all software distributed under the License are 14 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER 15 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES, 16 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY, 17 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT. 18 * Please see the License for the specific language governing rights and 19 * limitations under the License. 20 * 21 * @APPLE_LICENSE_HEADER_END@ 22 */ 23/* 24 * BLSupportsLegacyMode.c 25 * bless 26 * 27 * Created by Shantonu Sen on 2/10/06. 28 * Copyright 2006 Apple Computer. All Rights Reserved. 29 * 30 */ 31 32#include <IOKit/IOKitLib.h> 33#include <IOKit/IOKitKeys.h> 34 35#include <sys/stat.h> 36#include "bless.h" 37#include "bless_private.h" 38 39// Check if a system supports CSM legacy mode 40 41#define kBL_APPLE_VENDOR_NVRAM_GUID "4D1EDE05-38C7-4A6A-9CC6-4BCCA8B38C14" 42static bool _getFeatureFlags(BLContextPtr context, uint32_t *featureMask, 43 uint32_t *featureFlags); 44 45bool BLSupportsLegacyMode(BLContextPtr context) 46{ 47 48 uint32_t featureMask; 49 uint32_t featureFlags; 50 51 if(!_getFeatureFlags(context, &featureMask, &featureFlags)) { 52 return false; 53 } 54 55 if((featureMask & 0x00000001) 56 && (featureFlags & 0x00000001)) { 57 contextprintf(context, kBLLogLevelVerbose, "Legacy mode suppported\n"); 58 return true; 59 } 60 61 contextprintf(context, kBLLogLevelVerbose, "Legacy mode NOT suppported\n"); 62 return false; 63} 64 65static bool _getFeatureFlags(BLContextPtr context, uint32_t *featureMask, 66 uint32_t *featureFlags) 67{ 68 69 io_registry_entry_t optionsNode = IO_OBJECT_NULL; 70 CFDataRef dataRef; 71 72 optionsNode = IORegistryEntryFromPath(kIOMasterPortDefault, kIODeviceTreePlane ":/options"); 73 74 if(IO_OBJECT_NULL == optionsNode) { 75 contextprintf(context, kBLLogLevelVerbose, "Could not find " kIODeviceTreePlane ":/options\n"); 76 return false; 77 } 78 79 dataRef = IORegistryEntryCreateCFProperty(optionsNode, 80 CFSTR(kBL_APPLE_VENDOR_NVRAM_GUID ":FirmwareFeaturesMask"), 81 kCFAllocatorDefault, 0); 82 83 if(dataRef != NULL 84 && CFGetTypeID(dataRef) == CFDataGetTypeID() 85 && CFDataGetLength(dataRef) == sizeof(uint32_t)) { 86 const UInt8 *bytes = CFDataGetBytePtr(dataRef); 87 88 *featureMask = CFSwapInt32LittleToHost(*(uint32_t *)bytes); 89 } else { 90 *featureMask = 0x000003FF; 91 } 92 93 if(dataRef) CFRelease(dataRef); 94 95 dataRef = IORegistryEntryCreateCFProperty(optionsNode, 96 CFSTR(kBL_APPLE_VENDOR_NVRAM_GUID ":FirmwareFeatures"), 97 kCFAllocatorDefault, 0); 98 99 if(dataRef != NULL 100 && CFGetTypeID(dataRef) == CFDataGetTypeID() 101 && CFDataGetLength(dataRef) == sizeof(uint32_t)) { 102 const UInt8 *bytes = CFDataGetBytePtr(dataRef); 103 104 *featureFlags = CFSwapInt32LittleToHost(*(uint32_t *)bytes); 105 } else { 106 *featureFlags = 0x00000014; 107 } 108 109 if(dataRef) CFRelease(dataRef); 110 111 IOObjectRelease(optionsNode); 112 113 contextprintf(context, kBLLogLevelVerbose, "Firmware feature mask: 0x%08X\n", *featureMask); 114 contextprintf(context, kBLLogLevelVerbose, "Firmware features: 0x%08X\n", *featureFlags); 115 116 return true; 117} 118