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iokit/Kernel/IONVRAM.cpp xnu-792 xnu-4903.270.47
--- xnu/xnu-792/iokit/Kernel/IONVRAM.cpp
+++ xnu/xnu-4903.270.47/iokit/Kernel/IONVRAM.cpp
@@ -1,23 +1,30 @@
 /*
- * Copyright (c) 1998-2000 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 1998-2006 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2007-2012 Apple Inc. All rights reserved.
  *
- * @APPLE_LICENSE_HEADER_START@
- * 
- * The contents of this file constitute Original Code as defined in and
- * are subject to the Apple Public Source License Version 1.1 (the
- * "License").  You may not use this file except in compliance with the
- * License.  Please obtain a copy of the License at
- * http://www.apple.com/publicsource and read it before using this file.
- * 
- * This Original Code and all software distributed under the License are
- * distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
+ *
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. The rights granted to you under the License
+ * may not be used to create, or enable the creation or redistribution of,
+ * unlawful or unlicensed copies of an Apple operating system, or to
+ * circumvent, violate, or enable the circumvention or violation of, any
+ * terms of an Apple operating system software license agreement.
+ *
+ * Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this file.
+ *
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT.  Please see the
- * License for the specific language governing rights and limitations
- * under the License.
- * 
- * @APPLE_LICENSE_HEADER_END@
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ *
+ * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  */
 
 #include <IOKit/IOLib.h>
@@ -25,1619 +32,1723 @@
 #include <IOKit/IOPlatformExpert.h>
 #include <IOKit/IOUserClient.h>
 #include <IOKit/IOKitKeys.h>
+#include <IOKit/IOKitKeysPrivate.h>
+#include <kern/debug.h>
+#include <pexpert/pexpert.h>
 
 #define super IOService
 
-#define kIONVRAMPrivilege	kIOClientPrivilegeAdministrator
+#define kIONVRAMPrivilege       kIOClientPrivilegeAdministrator
 //#define kIONVRAMPrivilege	kIOClientPrivilegeLocalUser
 
-
 OSDefineMetaClassAndStructors(IODTNVRAM, IOService);
 
-bool IODTNVRAM::init(IORegistryEntry *old, const IORegistryPlane *plane)
-{
-  OSDictionary *dict;
-  
-  if (!super::init(old, plane)) return false;
-  
-  dict =  OSDictionary::withCapacity(1);
-  if (dict == 0) return false;
-  setPropertyTable(dict);
-  
-  _nvramImage = IONew(UInt8, kIODTNVRAMImageSize);
-  if (_nvramImage == 0) return false;
-  
-  _nvramPartitionOffsets = OSDictionary::withCapacity(1);
-  if (_nvramPartitionOffsets == 0) return false;
-  
-  _nvramPartitionLengths = OSDictionary::withCapacity(1);
-  if (_nvramPartitionLengths == 0) return false;
-  
-  _registryPropertiesKey = OSSymbol::withCStringNoCopy("aapl,pci");
-  if (_registryPropertiesKey == 0) return false;
-  
-  return true;
-}
-
-void IODTNVRAM::registerNVRAMController(IONVRAMController *nvram)
-{
-  char   partitionID[18];
-  UInt32 partitionOffset, partitionLength;
-  UInt32 freePartitionOffset, freePartitionSize;
-  UInt32 currentLength, currentOffset = 0;
-  OSNumber *partitionOffsetNumber, *partitionLengthNumber;
-  
-  if (_nvramController != 0) return;
-  
-  _nvramController = nvram;
-  
-  _nvramController->read(0, _nvramImage, kIODTNVRAMImageSize);
-  
-  // Find the offsets for the OF, XPRAM, NameRegistry and PanicInfo partitions.
-  _ofPartitionOffset = 0xFFFFFFFF;
-  _xpramPartitionOffset = 0xFFFFFFFF;
-  _nrPartitionOffset = 0xFFFFFFFF;
-  _piPartitionOffset = 0xFFFFFFFF;
-  freePartitionOffset = 0xFFFFFFFF;
-  freePartitionSize = 0;
-  if (getPlatform()->getBootROMType()) {
-    // Look through the partitions to find the OF, MacOS partitions.
-    while (currentOffset < kIODTNVRAMImageSize) {
-      currentLength = ((UInt16 *)(_nvramImage + currentOffset))[1] * 16;
-      
-      partitionOffset = currentOffset + 16;
-      partitionLength = currentLength - 16;
-      
-      if (strncmp((const char *)_nvramImage + currentOffset + 4,
-		  kIODTNVRAMOFPartitionName, 12) == 0) {
-	_ofPartitionOffset = partitionOffset;
-	_ofPartitionSize = partitionLength;
-      } else if (strncmp((const char *)_nvramImage + currentOffset + 4,
-			 kIODTNVRAMXPRAMPartitionName, 12) == 0) {
-	_xpramPartitionOffset = partitionOffset;
-	_xpramPartitionSize = kIODTNVRAMXPRAMSize;
-	_nrPartitionOffset = _xpramPartitionOffset + _xpramPartitionSize;
-	_nrPartitionSize = partitionLength - _xpramPartitionSize;
-      } else if (strncmp((const char *)_nvramImage + currentOffset + 4,
-			 kIODTNVRAMPanicInfoPartitonName, 12) == 0) {
-	_piPartitionOffset = partitionOffset;
-	_piPartitionSize = partitionLength;
-      } else if (strncmp((const char *)_nvramImage + currentOffset + 4,
-			 kIODTNVRAMFreePartitionName, 12) == 0) {
-	freePartitionOffset = currentOffset;
-	freePartitionSize = currentLength;
-      } else {
-	// Construct the partition ID from the signature and name.
-	sprintf(partitionID, "0x%02x,",
-		*(UInt8 *)(_nvramImage + currentOffset));
-	strncpy(partitionID + 5,
-		(const char *)(_nvramImage + currentOffset + 4), 12);
-	partitionID[17] = '\0';
-	
-	partitionOffsetNumber = OSNumber::withNumber(partitionOffset, 32);
-	partitionLengthNumber = OSNumber::withNumber(partitionLength, 32);
-	
-	// Save the partition offset and length
-	_nvramPartitionOffsets->setObject(partitionID, partitionOffsetNumber);
-	_nvramPartitionLengths->setObject(partitionID, partitionLengthNumber);
-	
-	partitionOffsetNumber->release();
-	partitionLengthNumber->release();
-      }
-      currentOffset += currentLength;
-    }
-  } else {
-    // Use the fixed address for old world machines.
-    _ofPartitionOffset    = 0x1800;
-    _ofPartitionSize      = 0x0800;
-    _xpramPartitionOffset = 0x1300;
-    _xpramPartitionSize   = 0x0100;
-    _nrPartitionOffset    = 0x1400;
-    _nrPartitionSize      = 0x0400;
-  }
-  
-  if (_ofPartitionOffset != 0xFFFFFFFF)
-    _ofImage    = _nvramImage + _ofPartitionOffset;
-  if (_xpramPartitionOffset != 0xFFFFFFFF)
-    _xpramImage = _nvramImage + _xpramPartitionOffset;
-  if (_nrPartitionOffset != 0xFFFFFFFF)
-    _nrImage    = _nvramImage + _nrPartitionOffset;
-  
-  if (_piPartitionOffset == 0xFFFFFFFF) {
-    if (freePartitionSize > 0x20) {
-      // Set the signature to 0xa1.
-      _nvramImage[freePartitionOffset] = 0xa1;
-      // Set the checksum to 0.
-      _nvramImage[freePartitionOffset + 1] = 0;
-      // Set the name for the Panic Info partition.
-      strncpy((char *)(_nvramImage + freePartitionOffset + 4),
-	      kIODTNVRAMPanicInfoPartitonName, 12);
-      
-      // Calculate the partition offset and size.
-      _piPartitionOffset = freePartitionOffset + 0x10;
-      _piPartitionSize = 0x800;
-      if (_piPartitionSize + 0x20 > freePartitionSize)
-	_piPartitionSize = freePartitionSize - 0x20;
-      
-      _piImage = _nvramImage + _piPartitionOffset;
-      
-      // Zero the new partition.
-      bzero(_piImage, _piPartitionSize);
-      
-      // Set the partition size.
-      *(UInt16 *)(_nvramImage + freePartitionOffset + 2) =
-	(_piPartitionSize / 0x10) + 1;
-      
-      // Set the partition checksum.
-      _nvramImage[freePartitionOffset + 1] =
-	calculatePartitionChecksum(_nvramImage + freePartitionOffset);
-      
-      // Calculate the free partition offset and size.
-      freePartitionOffset += _piPartitionSize + 0x10;
-      freePartitionSize -= _piPartitionSize + 0x10;
-      
-      // Set the signature to 0x7f.
-      _nvramImage[freePartitionOffset] = 0x7f;
-      // Set the checksum to 0.
-      _nvramImage[freePartitionOffset + 1] = 0;
-      // Set the name for the free partition.
-      strncpy((char *)(_nvramImage + freePartitionOffset + 4),
-	      kIODTNVRAMFreePartitionName, 12);
-      // Set the partition size.
-      *(UInt16 *)(_nvramImage + freePartitionOffset + 2) =
-	freePartitionSize / 0x10;
-      // Set the partition checksum.
-      _nvramImage[freePartitionOffset + 1] =
-	calculatePartitionChecksum(_nvramImage + freePartitionOffset);
-      
-      // Set the nvram image as dirty.
-      _nvramImageDirty = true;
-    }
-  } else {
-    _piImage = _nvramImage + _piPartitionOffset;
-  }
-  
-  initOFVariables();
-}
-
-void IODTNVRAM::sync(void)
-{
-  if (!_nvramImageDirty && !_ofImageDirty) return;
-  
-  // Don't try to sync OF Variables if the system has already paniced.
-  if (!_systemPaniced) syncOFVariables();
-  
-  _nvramController->write(0, _nvramImage, kIODTNVRAMImageSize);
-  _nvramController->sync();
-  
-  _nvramImageDirty = false;
-}
-
-bool IODTNVRAM::serializeProperties(OSSerialize *s) const
-{
-  bool                 result;
-  UInt32               variablePerm;
-  const OSSymbol       *key;
-  OSDictionary         *dict, *tmpDict = 0;
-  OSCollectionIterator *iter = 0;
-  
-  if (_ofDict == 0) return false;
-  
-  // Verify permissions.
-  result = IOUserClient::clientHasPrivilege(current_task(), kIONVRAMPrivilege);
-  if (result != kIOReturnSuccess) {
-    tmpDict = OSDictionary::withCapacity(1);
-    if (tmpDict == 0) return false;
-    
-    iter = OSCollectionIterator::withCollection(_ofDict);
-    if (iter == 0) return false;
-    
-    while (1) {
-      key = OSDynamicCast(OSSymbol, iter->getNextObject());
-      if (key == 0) break;
-      
-      variablePerm = getOFVariablePerm(key);
-      if (variablePerm != kOFVariablePermRootOnly) {
-	tmpDict->setObject(key, _ofDict->getObject(key));
-      }
-    }
-    dict = tmpDict;
-  } else {
-    dict = _ofDict;
-  }
-  
-  result = dict->serialize(s);
-  
-  if (tmpDict != 0) tmpDict->release();
-  if (iter != 0) iter->release();
-  
-  return result;
-}
-
-OSObject *IODTNVRAM::getProperty(const OSSymbol *aKey) const
-{
-  IOReturn result;
-  UInt32   variablePerm;
-  
-  if (_ofDict == 0) return 0;
-  
-  // Verify permissions.
-  result = IOUserClient::clientHasPrivilege(current_task(), kIONVRAMPrivilege);
-  if (result != kIOReturnSuccess) {
-    variablePerm = getOFVariablePerm(aKey);
-    if (variablePerm == kOFVariablePermRootOnly) return 0;
-  }
-  
-  return _ofDict->getObject(aKey);
-}
-
-OSObject *IODTNVRAM::getProperty(const char *aKey) const
-{
-  const OSSymbol *keySymbol;
-  OSObject *theObject = 0;
-  
-  keySymbol = OSSymbol::withCStringNoCopy(aKey);
-  if (keySymbol != 0) {
-    theObject = getProperty(keySymbol);
-    keySymbol->release();
-  }
-  
-  return theObject;
-}
-
-bool IODTNVRAM::setProperty(const OSSymbol *aKey, OSObject *anObject)
-{
-  bool     result;
-  UInt32   propType, propPerm;
-  OSString *tmpString;
-  OSObject *propObject = 0;
-  
-  if (_ofDict == 0) return false;
-  
-  // Verify permissions.
-  result = IOUserClient::clientHasPrivilege(current_task(), kIONVRAMPrivilege);
-  if (result != kIOReturnSuccess) {
-    propPerm = getOFVariablePerm(aKey);
-    if (propPerm != kOFVariablePermUserWrite) return false;
-  }
-  
-  // Don't allow creation of new properties on old world machines.
-  if (getPlatform()->getBootROMType() == 0) {
-    if (_ofDict->getObject(aKey) == 0) return false;
-  }
-  
-  // Don't allow change of 'aapl,panic-info'.
-  if (aKey->isEqualTo(kIODTNVRAMPanicInfoKey)) return false;
-  
-  // Make sure the object is of the correct type.
-  propType = getOFVariableType(aKey);
-  switch (propType) {
-  case kOFVariableTypeBoolean :
-    propObject = OSDynamicCast(OSBoolean, anObject);
-    break;
-    
-  case kOFVariableTypeNumber :
-    propObject = OSDynamicCast(OSNumber, anObject);
-    break;
-    
-  case kOFVariableTypeString :
-    propObject = OSDynamicCast(OSString, anObject);
-    break;
-    
-  case kOFVariableTypeData :
-    propObject = OSDynamicCast(OSData, anObject);
-    if (propObject == 0) {
-      tmpString = OSDynamicCast(OSString, anObject);
-      if (tmpString != 0) {
-	propObject = OSData::withBytes(tmpString->getCStringNoCopy(),
-				       tmpString->getLength());
-      }
-    }
-    break;
-  }
-  
-  if (propObject == 0) return false;
-  
-  result = _ofDict->setObject(aKey, propObject);
-  
-  if (result) {
-    if (getPlatform()->getBootROMType() == 0) {
-      updateOWBootArgs(aKey, propObject);
-    }
-    
-    _ofImageDirty = true;
-  }
-  
-  return result;
-}
-
-void IODTNVRAM::removeProperty(const OSSymbol *aKey)
-{
-  bool     result;
-  UInt32   propPerm;
-  
-  if (_ofDict == 0) return;
-  
-  // Verify permissions.
-  result = IOUserClient::clientHasPrivilege(current_task(), kIOClientPrivilegeAdministrator);
-  if (result != kIOReturnSuccess) {
-    propPerm = getOFVariablePerm(aKey);
-    if (propPerm != kOFVariablePermUserWrite) return;
-  }
-  
-  // Don't allow removal of properties on old world machines.
-  if (getPlatform()->getBootROMType() == 0) return;
-  
-  // Don't allow change of 'aapl,panic-info'.
-  if (aKey->isEqualTo(kIODTNVRAMPanicInfoKey)) return;
-  
-  // If the object exists, remove it from the dictionary.
-  result = _ofDict->getObject(aKey) != 0;
-  if (result) {
-    _ofDict->removeObject(aKey);
-    
-    _ofImageDirty = true;
-  }
-}
-
-IOReturn IODTNVRAM::setProperties(OSObject *properties)
-{
-  bool                 result = true;
-  OSObject             *object;
-  const OSSymbol       *key;
-  const OSString       *tmpStr;
-  OSDictionary         *dict;
-  OSCollectionIterator *iter;
-  
-  dict = OSDynamicCast(OSDictionary, properties);
-  if (dict == 0) return kIOReturnBadArgument;
-  
-  iter = OSCollectionIterator::withCollection(dict);
-  if (iter == 0) return kIOReturnBadArgument;
-  
-  while (result) {
-    key = OSDynamicCast(OSSymbol, iter->getNextObject());
-    if (key == 0) break;
-    
-    object = dict->getObject(key);
-    if (object == 0) continue;
-    
-    if (key->isEqualTo(kIONVRAMDeletePropertyKey)) {
-      tmpStr = OSDynamicCast(OSString, object);
-      if (tmpStr != 0) {
-	key = OSSymbol::withString(tmpStr);
-	removeProperty(key);
-	key->release();
-	result = true;
-      } else {
-	result = false;
-      }
-    } else {
-      result = setProperty(key, object);
-    }
-  }
-  
-  iter->release();
-  
-  if (result) return kIOReturnSuccess;
-  else return kIOReturnError;
-}
-
-IOReturn IODTNVRAM::readXPRAM(IOByteCount offset, UInt8 *buffer,
-			      IOByteCount length)
-{
-  if (_xpramImage == 0) return kIOReturnUnsupported;
-  
-  if ((buffer == 0) || (length == 0) ||
-      (offset + length > kIODTNVRAMXPRAMSize))
-    return kIOReturnBadArgument;
-  
-  bcopy(_nvramImage + _xpramPartitionOffset + offset, buffer, length);
-
-  return kIOReturnSuccess;
-}
-
-IOReturn IODTNVRAM::writeXPRAM(IOByteCount offset, UInt8 *buffer,
-			       IOByteCount length)
-{
-  if (_xpramImage == 0) return kIOReturnUnsupported;
-  
-  if ((buffer == 0) || (length == 0) ||
-      (offset + length > kIODTNVRAMXPRAMSize))
-    return kIOReturnBadArgument;
-  
-  bcopy(buffer, _nvramImage + _xpramPartitionOffset + offset, length);
-
-  _nvramImageDirty = true;
-  
-  return kIOReturnSuccess;
-}
-
-IOReturn IODTNVRAM::readNVRAMProperty(IORegistryEntry *entry,
-				      const OSSymbol **name,
-				      OSData **value)
-{
-  IOReturn err;
-
-  if (getPlatform()->getBootROMType())
-    err = readNVRAMPropertyType1(entry, name, value);
-  else
-    err = readNVRAMPropertyType0(entry, name, value);
-  
-  return err;
-}
-
-IOReturn IODTNVRAM::writeNVRAMProperty(IORegistryEntry *entry,
-				       const OSSymbol *name,
-				       OSData *value)
-{
-  IOReturn err;
-  
-  if (getPlatform()->getBootROMType())
-    err = writeNVRAMPropertyType1(entry, name, value);
-  else
-    err = writeNVRAMPropertyType0(entry, name, value);
-  
-  return err;
-}
-
-OSDictionary *IODTNVRAM::getNVRAMPartitions(void)
-{
-  return _nvramPartitionLengths;
-}
-
-IOReturn IODTNVRAM::readNVRAMPartition(const OSSymbol *partitionID,
-				       IOByteCount offset, UInt8 *buffer,
-				       IOByteCount length)
-{
-  OSNumber *partitionOffsetNumber, *partitionLengthNumber;
-  UInt32   partitionOffset, partitionLength;
-  
-  partitionOffsetNumber =
-    (OSNumber *)_nvramPartitionOffsets->getObject(partitionID);
-  partitionLengthNumber =
-    (OSNumber *)_nvramPartitionLengths->getObject(partitionID);
-  
-  if ((partitionOffsetNumber == 0) || (partitionLengthNumber == 0))
-    return kIOReturnNotFound;
-  
-  partitionOffset = partitionOffsetNumber->unsigned32BitValue();
-  partitionLength = partitionLengthNumber->unsigned32BitValue();
-  
-  if ((buffer == 0) || (length == 0) ||
-      (offset + length > partitionLength))
-    return kIOReturnBadArgument;
-  
-  bcopy(_nvramImage + partitionOffset + offset, buffer, length);
-  
-  return kIOReturnSuccess;
-}
-
-IOReturn IODTNVRAM::writeNVRAMPartition(const OSSymbol *partitionID,
-					IOByteCount offset, UInt8 *buffer,
-					IOByteCount length)
-{
-  OSNumber *partitionOffsetNumber, *partitionLengthNumber;
-  UInt32   partitionOffset, partitionLength;
-  
-  partitionOffsetNumber =
-    (OSNumber *)_nvramPartitionOffsets->getObject(partitionID);
-  partitionLengthNumber =
-    (OSNumber *)_nvramPartitionLengths->getObject(partitionID);
-  
-  if ((partitionOffsetNumber == 0) || (partitionLengthNumber == 0))
-    return kIOReturnNotFound;
-  
-  partitionOffset = partitionOffsetNumber->unsigned32BitValue();
-  partitionLength = partitionLengthNumber->unsigned32BitValue();
-  
-  if ((buffer == 0) || (length == 0) ||
-      (offset + length > partitionLength))
-    return kIOReturnBadArgument;
-  
-  bcopy(buffer, _nvramImage + partitionOffset + offset, length);
-  
-  _nvramImageDirty = true;
-  
-  return kIOReturnSuccess;
-}
-
-UInt32 IODTNVRAM::savePanicInfo(UInt8 *buffer, IOByteCount length)
-{
-  if ((_piImage == 0) || (length <= 0)) return 0;
-  
-  if (length > (_piPartitionSize - 4))
-    length = _piPartitionSize - 4;
-  
-  // Save the Panic Info.
-  bcopy(buffer, _piImage + 4, length);
-  
-  // Save the Panic Info length.
-  *(UInt32 *)_piImage = length;
-  
-  _nvramImageDirty = true;
-  
-  _systemPaniced = true;
-  
-  return length;
+bool
+IODTNVRAM::init(IORegistryEntry *old, const IORegistryPlane *plane)
+{
+	OSDictionary *dict;
+
+	if (!super::init(old, plane)) {
+		return false;
+	}
+
+	dict =  OSDictionary::withCapacity(1);
+	if (dict == 0) {
+		return false;
+	}
+	setPropertyTable(dict);
+
+	_nvramImage = IONew(UInt8, kIODTNVRAMImageSize);
+	if (_nvramImage == 0) {
+		return false;
+	}
+
+	_nvramPartitionOffsets = OSDictionary::withCapacity(1);
+	if (_nvramPartitionOffsets == 0) {
+		return false;
+	}
+
+	_nvramPartitionLengths = OSDictionary::withCapacity(1);
+	if (_nvramPartitionLengths == 0) {
+		return false;
+	}
+
+	_registryPropertiesKey = OSSymbol::withCStringNoCopy("aapl,pci");
+	if (_registryPropertiesKey == 0) {
+		return false;
+	}
+
+	// <rdar://problem/9529235> race condition possible between
+	// IODTNVRAM and IONVRAMController (restore loses boot-args)
+	initProxyData();
+
+	return true;
+}
+
+void
+IODTNVRAM::initProxyData(void)
+{
+	IORegistryEntry *entry;
+	const char *key = "nvram-proxy-data";
+	OSObject *prop;
+	OSData *data;
+	const void *bytes;
+
+	entry = IORegistryEntry::fromPath("/chosen", gIODTPlane);
+	if (entry != 0) {
+		prop = entry->getProperty(key);
+		if (prop != 0) {
+			data = OSDynamicCast(OSData, prop);
+			if (data != 0) {
+				bytes = data->getBytesNoCopy();
+				if ((bytes != 0) && (data->getLength() <= kIODTNVRAMImageSize)) {
+					bcopy(bytes, _nvramImage, data->getLength());
+					initNVRAMImage();
+					_isProxied = true;
+				}
+			}
+		}
+		entry->removeProperty(key);
+		entry->release();
+	}
+}
+
+void
+IODTNVRAM::registerNVRAMController(IONVRAMController *nvram)
+{
+	if (_nvramController != 0) {
+		return;
+	}
+
+	_nvramController = nvram;
+
+	// <rdar://problem/9529235> race condition possible between
+	// IODTNVRAM and IONVRAMController (restore loses boot-args)
+	if (!_isProxied) {
+		_nvramController->read(0, _nvramImage, kIODTNVRAMImageSize);
+		initNVRAMImage();
+	} else {
+		IOLockLock(_ofLock);
+		(void) syncVariables();
+		IOLockUnlock(_ofLock);
+	}
+}
+
+void
+IODTNVRAM::initNVRAMImage(void)
+{
+	char   partitionID[18];
+	UInt32 partitionOffset, partitionLength;
+	UInt32 freePartitionOffset, freePartitionSize;
+	UInt32 currentLength, currentOffset = 0;
+	OSNumber *partitionOffsetNumber, *partitionLengthNumber;
+
+	// Find the offsets for the OF, XPRAM, NameRegistry and PanicInfo partitions.
+	_ofPartitionOffset = 0xFFFFFFFF;
+	_piPartitionOffset = 0xFFFFFFFF;
+	freePartitionOffset = 0xFFFFFFFF;
+	freePartitionSize = 0;
+
+	// Look through the partitions to find the OF, MacOS partitions.
+	while (currentOffset < kIODTNVRAMImageSize) {
+		currentLength = ((UInt16 *)(_nvramImage + currentOffset))[1] * 16;
+
+		if (currentLength < 16) {
+			break;
+		}
+		partitionOffset = currentOffset + 16;
+		partitionLength = currentLength - 16;
+		if ((partitionOffset + partitionLength) > kIODTNVRAMImageSize) {
+			break;
+		}
+
+		if (strncmp((const char *)_nvramImage + currentOffset + 4,
+		    kIODTNVRAMOFPartitionName, 12) == 0) {
+			_ofPartitionOffset = partitionOffset;
+			_ofPartitionSize = partitionLength;
+		} else if (strncmp((const char *)_nvramImage + currentOffset + 4,
+		    kIODTNVRAMXPRAMPartitionName, 12) == 0) {
+		} else if (strncmp((const char *)_nvramImage + currentOffset + 4,
+		    kIODTNVRAMPanicInfoPartitonName, 12) == 0) {
+			_piPartitionOffset = partitionOffset;
+			_piPartitionSize = partitionLength;
+		} else if (strncmp((const char *)_nvramImage + currentOffset + 4,
+		    kIODTNVRAMFreePartitionName, 12) == 0) {
+			freePartitionOffset = currentOffset;
+			freePartitionSize = currentLength;
+		} else {
+			// Construct the partition ID from the signature and name.
+			snprintf(partitionID, sizeof(partitionID), "0x%02x,",
+			    *(UInt8 *)(_nvramImage + currentOffset));
+			strncpy(partitionID + 5,
+			    (const char *)(_nvramImage + currentOffset + 4), 12);
+			partitionID[17] = '\0';
+
+			partitionOffsetNumber = OSNumber::withNumber(partitionOffset, 32);
+			partitionLengthNumber = OSNumber::withNumber(partitionLength, 32);
+
+			// Save the partition offset and length
+			_nvramPartitionOffsets->setObject(partitionID, partitionOffsetNumber);
+			_nvramPartitionLengths->setObject(partitionID, partitionLengthNumber);
+
+			partitionOffsetNumber->release();
+			partitionLengthNumber->release();
+		}
+		currentOffset += currentLength;
+	}
+
+	if (_ofPartitionOffset != 0xFFFFFFFF) {
+		_ofImage    = _nvramImage + _ofPartitionOffset;
+	}
+
+	if (_piPartitionOffset == 0xFFFFFFFF) {
+		if (freePartitionSize > 0x20) {
+			// Set the signature to 0xa1.
+			_nvramImage[freePartitionOffset] = 0xa1;
+			// Set the checksum to 0.
+			_nvramImage[freePartitionOffset + 1] = 0;
+			// Set the name for the Panic Info partition.
+			strncpy((char *)(_nvramImage + freePartitionOffset + 4),
+			    kIODTNVRAMPanicInfoPartitonName, 12);
+
+			// Calculate the partition offset and size.
+			_piPartitionOffset = freePartitionOffset + 0x10;
+			_piPartitionSize = 0x800;
+			if (_piPartitionSize + 0x20 > freePartitionSize) {
+				_piPartitionSize = freePartitionSize - 0x20;
+			}
+
+			_piImage = _nvramImage + _piPartitionOffset;
+
+			// Zero the new partition.
+			bzero(_piImage, _piPartitionSize);
+
+			// Set the partition size.
+			*(UInt16 *)(_nvramImage + freePartitionOffset + 2) =
+			    (_piPartitionSize / 0x10) + 1;
+
+			// Set the partition checksum.
+			_nvramImage[freePartitionOffset + 1] =
+			    calculatePartitionChecksum(_nvramImage + freePartitionOffset);
+
+			// Calculate the free partition offset and size.
+			freePartitionOffset += _piPartitionSize + 0x10;
+			freePartitionSize -= _piPartitionSize + 0x10;
+
+			// Set the signature to 0x7f.
+			_nvramImage[freePartitionOffset] = 0x7f;
+			// Set the checksum to 0.
+			_nvramImage[freePartitionOffset + 1] = 0;
+			// Set the name for the free partition.
+			strncpy((char *)(_nvramImage + freePartitionOffset + 4),
+			    kIODTNVRAMFreePartitionName, 12);
+			// Set the partition size.
+			*(UInt16 *)(_nvramImage + freePartitionOffset + 2) =
+			    freePartitionSize / 0x10;
+			// Set the partition checksum.
+			_nvramImage[freePartitionOffset + 1] =
+			    calculatePartitionChecksum(_nvramImage + freePartitionOffset);
+
+			if (_nvramController != 0) {
+				_nvramController->write(0, _nvramImage, kIODTNVRAMImageSize);
+			}
+		}
+	} else {
+		_piImage = _nvramImage + _piPartitionOffset;
+	}
+
+	_lastDeviceSync = 0;
+	_freshInterval = TRUE;          // we will allow sync() even before the first 15 minutes have passed.
+
+	initOFVariables();
+}
+
+void
+IODTNVRAM::syncInternal(bool rateLimit)
+{
+	// Don't try to perform controller operations if none has been registered.
+	if (_nvramController == 0) {
+		return;
+	}
+
+	// Rate limit requests to sync. Drivers that need this rate limiting will
+	// shadow the data and only write to flash when they get a sync call
+	if (rateLimit && !safeToSync()) {
+		return;
+	}
+
+	_nvramController->sync();
+}
+
+void
+IODTNVRAM::sync(void)
+{
+	syncInternal(false);
+}
+
+bool
+IODTNVRAM::serializeProperties(OSSerialize *s) const
+{
+	bool                 result, hasPrivilege;
+	UInt32               variablePerm;
+	const OSSymbol       *key;
+	OSDictionary         *dict;
+	OSCollectionIterator *iter = 0;
+
+	// Verify permissions.
+	hasPrivilege = (kIOReturnSuccess == IOUserClient::clientHasPrivilege(current_task(), kIONVRAMPrivilege));
+
+	if (_ofDict == 0) {
+		/* No nvram. Return an empty dictionary. */
+		dict = OSDictionary::withCapacity(1);
+		if (dict == 0) {
+			return false;
+		}
+	} else {
+		IOLockLock(_ofLock);
+		dict = OSDictionary::withDictionary(_ofDict);
+		IOLockUnlock(_ofLock);
+		if (dict == 0) {
+			return false;
+		}
+
+		/* Copy properties with client privilege. */
+		iter = OSCollectionIterator::withCollection(dict);
+		if (iter == 0) {
+			dict->release();
+			return false;
+		}
+		while (1) {
+			key = OSDynamicCast(OSSymbol, iter->getNextObject());
+			if (key == 0) {
+				break;
+			}
+
+			variablePerm = getOFVariablePerm(key);
+			if ((hasPrivilege || (variablePerm != kOFVariablePermRootOnly)) &&
+			    (!(variablePerm == kOFVariablePermKernelOnly && current_task() != kernel_task))) {
+			} else {
+				dict->removeObject(key);
+				iter->reset();
+			}
+		}
+	}
+
+	result = dict->serialize(s);
+
+	dict->release();
+	if (iter != 0) {
+		iter->release();
+	}
+
+	return result;
+}
+
+OSObject *
+IODTNVRAM::copyProperty(const OSSymbol *aKey) const
+{
+	IOReturn result;
+	UInt32   variablePerm;
+	OSObject *theObject;
+
+	if (_ofDict == 0) {
+		return 0;
+	}
+
+	// Verify permissions.
+	variablePerm = getOFVariablePerm(aKey);
+	result = IOUserClient::clientHasPrivilege(current_task(), kIONVRAMPrivilege);
+	if (result != kIOReturnSuccess) {
+		if (variablePerm == kOFVariablePermRootOnly) {
+			return 0;
+		}
+	}
+	if (variablePerm == kOFVariablePermKernelOnly && current_task() != kernel_task) {
+		return 0;
+	}
+
+	IOLockLock(_ofLock);
+	theObject = _ofDict->getObject(aKey);
+	if (theObject) {
+		theObject->retain();
+	}
+	IOLockUnlock(_ofLock);
+
+	return theObject;
+}
+
+OSObject *
+IODTNVRAM::copyProperty(const char *aKey) const
+{
+	const OSSymbol *keySymbol;
+	OSObject *theObject = 0;
+
+	keySymbol = OSSymbol::withCString(aKey);
+	if (keySymbol != 0) {
+		theObject = copyProperty(keySymbol);
+		keySymbol->release();
+	}
+
+	return theObject;
+}
+
+OSObject *
+IODTNVRAM::getProperty(const OSSymbol *aKey) const
+{
+	OSObject *theObject;
+
+	theObject = copyProperty(aKey);
+	if (theObject) {
+		theObject->release();
+	}
+
+	return theObject;
+}
+
+OSObject *
+IODTNVRAM::getProperty(const char *aKey) const
+{
+	OSObject *theObject;
+
+	theObject = copyProperty(aKey);
+	if (theObject) {
+		theObject->release();
+	}
+
+	return theObject;
+}
+
+bool
+IODTNVRAM::setProperty(const OSSymbol *aKey, OSObject *anObject)
+{
+	bool     result;
+	UInt32   propType, propPerm;
+	OSString *tmpString = 0;
+	OSObject *propObject = 0, *oldObject;
+
+	if (_ofDict == 0) {
+		return false;
+	}
+
+	// Verify permissions.
+	propPerm = getOFVariablePerm(aKey);
+	if (IOUserClient::clientHasPrivilege(current_task(), kIONVRAMPrivilege) != kIOReturnSuccess) {
+		if (propPerm != kOFVariablePermUserWrite) {
+			return false;
+		}
+	}
+	if (propPerm == kOFVariablePermKernelOnly && current_task() != kernel_task) {
+		return 0;
+	}
+
+	// Don't allow change of 'aapl,panic-info'.
+	if (aKey->isEqualTo(kIODTNVRAMPanicInfoKey)) {
+		return false;
+	}
+
+	// Make sure the object is of the correct type.
+	propType = getOFVariableType(aKey);
+	switch (propType) {
+	case kOFVariableTypeBoolean:
+		propObject = OSDynamicCast(OSBoolean, anObject);
+		break;
+
+	case kOFVariableTypeNumber:
+		propObject = OSDynamicCast(OSNumber, anObject);
+		break;
+
+	case kOFVariableTypeString:
+		propObject = OSDynamicCast(OSString, anObject);
+		break;
+
+	case kOFVariableTypeData:
+		propObject = OSDynamicCast(OSData, anObject);
+		if (propObject == 0) {
+			tmpString = OSDynamicCast(OSString, anObject);
+			if (tmpString != 0) {
+				propObject = OSData::withBytes(tmpString->getCStringNoCopy(),
+				    tmpString->getLength());
+			}
+		}
+		break;
+	}
+
+	if (propObject == 0) {
+		return false;
+	}
+
+	IOLockLock(_ofLock);
+
+	oldObject = _ofDict->getObject(aKey);
+	if (oldObject) {
+		oldObject->retain();
+	}
+	result = _ofDict->setObject(aKey, propObject);
+
+	if (result) {
+		if (syncVariables() != kIOReturnSuccess) {
+			if (oldObject) {
+				_ofDict->setObject(aKey, oldObject);
+			} else {
+				_ofDict->removeObject(aKey);
+			}
+			(void) syncVariables();
+			result = false;
+		}
+	}
+
+	if (oldObject) {
+		oldObject->release();
+	}
+	if (tmpString) {
+		propObject->release();
+	}
+
+	IOLockUnlock(_ofLock);
+
+	return result;
+}
+
+void
+IODTNVRAM::removeProperty(const OSSymbol *aKey)
+{
+	bool     result;
+	UInt32   propPerm;
+
+	if (_ofDict == 0) {
+		return;
+	}
+
+	// Verify permissions.
+	propPerm = getOFVariablePerm(aKey);
+	result = IOUserClient::clientHasPrivilege(current_task(), kIOClientPrivilegeAdministrator);
+	if (result != kIOReturnSuccess) {
+		if (propPerm != kOFVariablePermUserWrite) {
+			return;
+		}
+	}
+	if (propPerm == kOFVariablePermKernelOnly && current_task() != kernel_task) {
+		return;
+	}
+
+	// Don't allow change of 'aapl,panic-info'.
+	if (aKey->isEqualTo(kIODTNVRAMPanicInfoKey)) {
+		return;
+	}
+
+	// If the object exists, remove it from the dictionary.
+
+	IOLockLock(_ofLock);
+	result = _ofDict->getObject(aKey) != 0;
+	if (result) {
+		_ofDict->removeObject(aKey);
+	}
+
+	if (result) {
+		(void) syncVariables();
+	}
+
+	IOLockUnlock(_ofLock);
+}
+
+IOReturn
+IODTNVRAM::setProperties(OSObject *properties)
+{
+	bool                 result = true;
+	OSObject             *object;
+	const OSSymbol       *key;
+	const OSString       *tmpStr;
+	OSDictionary         *dict;
+	OSCollectionIterator *iter;
+
+	dict = OSDynamicCast(OSDictionary, properties);
+	if (dict == 0) {
+		return kIOReturnBadArgument;
+	}
+
+	iter = OSCollectionIterator::withCollection(dict);
+	if (iter == 0) {
+		return kIOReturnBadArgument;
+	}
+
+	while (result) {
+		key = OSDynamicCast(OSSymbol, iter->getNextObject());
+		if (key == 0) {
+			break;
+		}
+
+		object = dict->getObject(key);
+		if (object == 0) {
+			continue;
+		}
+
+		if (key->isEqualTo(kIONVRAMDeletePropertyKey)) {
+			tmpStr = OSDynamicCast(OSString, object);
+			if (tmpStr != 0) {
+				key = OSSymbol::withString(tmpStr);
+				removeProperty(key);
+				key->release();
+				result = true;
+			} else {
+				result = false;
+			}
+		} else if (key->isEqualTo(kIONVRAMSyncNowPropertyKey) || key->isEqualTo(kIONVRAMForceSyncNowPropertyKey)) {
+			tmpStr = OSDynamicCast(OSString, object);
+			if (tmpStr != 0) {
+				result = true;
+
+				// We still want to throttle NVRAM commit rate for SyncNow. ForceSyncNow is provided as a really big hammer.
+
+				syncInternal(key->isEqualTo(kIONVRAMSyncNowPropertyKey));
+			} else {
+				result = false;
+			}
+		} else {
+			result = setProperty(key, object);
+		}
+	}
+
+	iter->release();
+
+	if (result) {
+		return kIOReturnSuccess;
+	} else {
+		return kIOReturnError;
+	}
+}
+
+IOReturn
+IODTNVRAM::readXPRAM(IOByteCount offset, UInt8 *buffer,
+    IOByteCount length)
+{
+	return kIOReturnUnsupported;
+}
+
+IOReturn
+IODTNVRAM::writeXPRAM(IOByteCount offset, UInt8 *buffer,
+    IOByteCount length)
+{
+	return kIOReturnUnsupported;
+}
+
+IOReturn
+IODTNVRAM::readNVRAMProperty(IORegistryEntry *entry,
+    const OSSymbol **name,
+    OSData **value)
+{
+	IOReturn err;
+
+	err = readNVRAMPropertyType1(entry, name, value);
+
+	return err;
+}
+
+IOReturn
+IODTNVRAM::writeNVRAMProperty(IORegistryEntry *entry,
+    const OSSymbol *name,
+    OSData *value)
+{
+	IOReturn err;
+
+	err = writeNVRAMPropertyType1(entry, name, value);
+
+	return err;
+}
+
+OSDictionary *
+IODTNVRAM::getNVRAMPartitions(void)
+{
+	return _nvramPartitionLengths;
+}
+
+IOReturn
+IODTNVRAM::readNVRAMPartition(const OSSymbol *partitionID,
+    IOByteCount offset, UInt8 *buffer,
+    IOByteCount length)
+{
+	OSNumber *partitionOffsetNumber, *partitionLengthNumber;
+	UInt32   partitionOffset, partitionLength, end;
+
+	partitionOffsetNumber =
+	    (OSNumber *)_nvramPartitionOffsets->getObject(partitionID);
+	partitionLengthNumber =
+	    (OSNumber *)_nvramPartitionLengths->getObject(partitionID);
+
+	if ((partitionOffsetNumber == 0) || (partitionLengthNumber == 0)) {
+		return kIOReturnNotFound;
+	}
+
+	partitionOffset = partitionOffsetNumber->unsigned32BitValue();
+	partitionLength = partitionLengthNumber->unsigned32BitValue();
+
+	if (os_add_overflow(offset, length, &end)) {
+		return kIOReturnBadArgument;
+	}
+	if ((buffer == 0) || (length == 0) || (end > partitionLength)) {
+		return kIOReturnBadArgument;
+	}
+
+	bcopy(_nvramImage + partitionOffset + offset, buffer, length);
+
+	return kIOReturnSuccess;
+}
+
+IOReturn
+IODTNVRAM::writeNVRAMPartition(const OSSymbol *partitionID,
+    IOByteCount offset, UInt8 *buffer,
+    IOByteCount length)
+{
+	OSNumber *partitionOffsetNumber, *partitionLengthNumber;
+	UInt32   partitionOffset, partitionLength, end;
+
+	partitionOffsetNumber =
+	    (OSNumber *)_nvramPartitionOffsets->getObject(partitionID);
+	partitionLengthNumber =
+	    (OSNumber *)_nvramPartitionLengths->getObject(partitionID);
+
+	if ((partitionOffsetNumber == 0) || (partitionLengthNumber == 0)) {
+		return kIOReturnNotFound;
+	}
+
+	partitionOffset = partitionOffsetNumber->unsigned32BitValue();
+	partitionLength = partitionLengthNumber->unsigned32BitValue();
+
+	if (os_add_overflow(offset, length, &end)) {
+		return kIOReturnBadArgument;
+	}
+	if ((buffer == 0) || (length == 0) || (end > partitionLength)) {
+		return kIOReturnBadArgument;
+	}
+
+	bcopy(buffer, _nvramImage + partitionOffset + offset, length);
+
+	if (_nvramController != 0) {
+		_nvramController->write(0, _nvramImage, kIODTNVRAMImageSize);
+	}
+
+	return kIOReturnSuccess;
+}
+
+IOByteCount
+IODTNVRAM::savePanicInfo(UInt8 *buffer, IOByteCount length)
+{
+	if ((_piImage == 0) || (length <= 0)) {
+		return 0;
+	}
+
+	if (length > (_piPartitionSize - 4)) {
+		length = _piPartitionSize - 4;
+	}
+
+	// Save the Panic Info.
+	bcopy(buffer, _piImage + 4, length);
+
+	// Save the Panic Info length.
+	*(UInt32 *)_piImage = length;
+
+	if (_nvramController != 0) {
+		_nvramController->write(0, _nvramImage, kIODTNVRAMImageSize);
+	}
+	/*
+	 * This prevents OF variables from being committed if the system has panicked
+	 */
+	_systemPaniced = true;
+	/* The call to sync() forces the NVRAM controller to write the panic info
+	 * partition to NVRAM.
+	 */
+	sync();
+
+	return length;
 }
 
 // Private methods
 
-UInt8 IODTNVRAM::calculatePartitionChecksum(UInt8 *partitionHeader)
-{
-  UInt8 cnt, isum, csum = 0;
-  
-  for (cnt = 0; cnt < 0x10; cnt++) {
-    isum = csum + partitionHeader[cnt];
-    if (isum < csum) isum++;
-    csum = isum;
-  }
-  
-  return csum;
-}
-
-struct OWVariablesHeader {
-  UInt16   owMagic;
-  UInt8    owVersion;
-  UInt8    owPages;
-  UInt16   owChecksum;
-  UInt16   owHere;
-  UInt16   owTop;
-  UInt16   owNext;
-  UInt32   owFlags;
-  UInt32   owNumbers[9];
-  struct {
-    UInt16 offset;
-    UInt16 length;
-  }        owStrings[10];
-};
-typedef struct OWVariablesHeader OWVariablesHeader;
-
-IOReturn IODTNVRAM::initOFVariables(void)
-{
-  UInt32            cnt, propOffset, propType;
-  UInt8             *propName, *propData;
-  UInt32            propNameLength, propDataLength;
-  const OSSymbol    *propSymbol;
-  OSObject          *propObject;
-  OWVariablesHeader *owHeader;
-
-  if (_ofImage == 0) return kIOReturnNotReady;
-  
-  _ofDict =  OSDictionary::withCapacity(1);
-  if (_ofDict == 0) return kIOReturnNoMemory;
-  
-  if (getPlatform()->getBootROMType()) {
-    cnt = 0;
-    while (cnt < _ofPartitionSize) {
-      // Break if there is no name.
-      if (_ofImage[cnt] == '\0') break;
-      
-      // Find the length of the name.
-      propName = _ofImage + cnt;
-      for (propNameLength = 0; (cnt + propNameLength) < _ofPartitionSize;
-	   propNameLength++) {
-	if (_ofImage[cnt + propNameLength] == '=') break;
-      }
-      
-      // Break if the name goes past the end of the partition.
-      if ((cnt + propNameLength) >= _ofPartitionSize) break;
-      cnt += propNameLength + 1;
-      
-      propData = _ofImage + cnt;
-      for (propDataLength = 0; (cnt + propDataLength) < _ofPartitionSize;
-	   propDataLength++) {
-	if (_ofImage[cnt + propDataLength] == '\0') break;
-      }
-      
-      // Break if the data goes past the end of the partition.
-      if ((cnt + propDataLength) >= _ofPartitionSize) break;
-      cnt += propDataLength + 1;
-      
-      if (convertPropToObject(propName, propNameLength,
-			      propData, propDataLength,
-			      &propSymbol, &propObject)) {
-	_ofDict->setObject(propSymbol, propObject);
-	propSymbol->release();
-	propObject->release();
-      }
-    }
-    
-    // Create the boot-args property if it is not in the dictionary.
-    if (_ofDict->getObject("boot-args") == 0) {
-      propObject = OSString::withCStringNoCopy("");
-      if (propObject != 0) {
-	_ofDict->setObject("boot-args", propObject);
-	propObject->release();
-      }
-    }
-    
-    // Create the 'aapl,panic-info' property if needed.
-    if (_piImage != 0) {
-      propDataLength = *(UInt32 *)_piImage;
-      if ((propDataLength != 0) && (propDataLength < (_piPartitionSize - 4))) {
-	propObject = OSData::withBytes(_piImage + 4, propDataLength);
-	_ofDict->setObject(kIODTNVRAMPanicInfoKey, propObject);
-	propObject->release();
-	
-	// Clear the length from _piImage and mark dirty.
-	*(UInt32 *)_piImage = 0;
-	_nvramImageDirty = true;
-      }
-    }
-  } else {
-    owHeader = (OWVariablesHeader *)_ofImage;
-    if (!validateOWChecksum(_ofImage)) {
-      _ofDict->release();
-      _ofDict = 0;
-      return kIOReturnBadMedia;
-    }
-    
-    cnt = 0;
-    while (1) {
-      if (!getOWVariableInfo(cnt++, &propSymbol, &propType, &propOffset))
-	break;
-      
-      switch (propType) {
-      case kOFVariableTypeBoolean :
-	propObject = OSBoolean::withBoolean(owHeader->owFlags & propOffset);
-	break;
-	
-      case kOFVariableTypeNumber :
-	propObject = OSNumber::withNumber(owHeader->owNumbers[propOffset], 32);
-	break;
-	
-      case kOFVariableTypeString :
-	propData = _ofImage + owHeader->owStrings[propOffset].offset -
-	  _ofPartitionOffset;
-	propDataLength = owHeader->owStrings[propOffset].length;
-	propName = IONew(UInt8, propDataLength + 1);
-	if (propName != 0) {
-	  strncpy((char *)propName, (const char *)propData, propDataLength);
-	  propName[propDataLength] = '\0';
-	  propObject = OSString::withCString((const char *)propName);
-	  IODelete(propName, UInt8, propDataLength + 1);
-	}
-	break;
-      }
-      
-      if (propObject == 0) break;
-      
-      _ofDict->setObject(propSymbol, propObject);
-      propSymbol->release();
-      propObject->release();
-    }
-    
-    // Create the boot-args property.
-    propSymbol = OSSymbol::withCString("boot-command");
-    if (propSymbol != 0) {
-      propObject = _ofDict->getObject(propSymbol);
-      if (propObject != 0) {
-	updateOWBootArgs(propSymbol, propObject);
-      }
-      propSymbol->release();
-    }
-  }
-  
-  return kIOReturnSuccess;
-}
-
-IOReturn IODTNVRAM::syncOFVariables(void)
-{
-  bool                 ok;
-  UInt32               cnt, length, maxLength;
-  UInt32               curOffset, tmpOffset, tmpType, tmpDataLength;
-  UInt8                *buffer, *tmpBuffer;
-  const UInt8          *tmpData;
-  const OSSymbol       *tmpSymbol;
-  OSObject             *tmpObject;
-  OSBoolean            *tmpBoolean;
-  OSNumber             *tmpNumber;
-  OSString             *tmpString;
-  OSCollectionIterator *iter;
-  OWVariablesHeader    *owHeader, *owHeaderOld;
-  
-  if ((_ofImage == 0) || (_ofDict == 0)) return kIOReturnNotReady;
-  
-  if (!_ofImageDirty) return kIOReturnSuccess;
-  
-  if (getPlatform()->getBootROMType()) {
-    buffer = tmpBuffer = IONew(UInt8, _ofPartitionSize);
-    if (buffer == 0) return kIOReturnNoMemory;
-    bzero(buffer, _ofPartitionSize);
-    
-    ok = true;
-    maxLength = _ofPartitionSize;
-    
-    iter = OSCollectionIterator::withCollection(_ofDict);
-    if (iter == 0) ok = false;
-    
-    while (ok) {
-      tmpSymbol = OSDynamicCast(OSSymbol, iter->getNextObject());
-      if (tmpSymbol == 0) break;
-      
-      // Don't save 'aapl,panic-info'.
-      if (tmpSymbol->isEqualTo(kIODTNVRAMPanicInfoKey)) continue;
-      
-      tmpObject = _ofDict->getObject(tmpSymbol);
-      
-      length = maxLength;
-      ok = convertObjectToProp(tmpBuffer, &length, tmpSymbol, tmpObject);
-      if (ok) {
-	tmpBuffer += length;
-	maxLength -= length;
-      }
-    }
-    iter->release();
-    
-    if (ok) {
-      bcopy(buffer, _ofImage, _ofPartitionSize);
-    }
-    
-    IODelete(buffer, UInt8, _ofPartitionSize);
-    
-    if (!ok) return kIOReturnBadArgument;
-  } else {
-    buffer = IONew(UInt8, _ofPartitionSize);
-    if (buffer == 0) return kIOReturnNoMemory;
-    bzero(buffer, _ofPartitionSize);
-    
-    owHeader    = (OWVariablesHeader *)buffer;
-    owHeaderOld = (OWVariablesHeader *)_ofImage;
-    
-    owHeader->owMagic = owHeaderOld->owMagic;
-    owHeader->owVersion = owHeaderOld->owVersion;
-    owHeader->owPages = owHeaderOld->owPages;
-    
-    curOffset = _ofPartitionSize;
-    
-    ok = true;
-    cnt = 0;
-    while (ok) {
-      if (!getOWVariableInfo(cnt++, &tmpSymbol, &tmpType, &tmpOffset))
-	break;
-      
-      tmpObject = _ofDict->getObject(tmpSymbol);
-      
-      switch (tmpType) {
-      case kOFVariableTypeBoolean :
-	tmpBoolean = OSDynamicCast(OSBoolean, tmpObject);
-	if (tmpBoolean->getValue()) owHeader->owFlags |= tmpOffset;
-	break;
-	
-      case kOFVariableTypeNumber :
-	tmpNumber = OSDynamicCast(OSNumber, tmpObject);
-	owHeader->owNumbers[tmpOffset] = tmpNumber->unsigned32BitValue();
-        break;
-	
-      case kOFVariableTypeString :
-	tmpString = OSDynamicCast(OSString, tmpObject);
-	tmpData = (const UInt8 *)tmpString->getCStringNoCopy();
-	tmpDataLength = tmpString->getLength();
-	
-	if ((curOffset - tmpDataLength) < sizeof(OWVariablesHeader)) {
-	  ok = false;
-	  break;
-	}
-	
-	owHeader->owStrings[tmpOffset].length = tmpDataLength;
-	curOffset -= tmpDataLength;
-	owHeader->owStrings[tmpOffset].offset = curOffset + _ofPartitionOffset;
-	if (tmpDataLength != 0)
-	  bcopy(tmpData, buffer + curOffset, tmpDataLength);
-	break;
-      }
-    }
-    
-    if (ok) {
-      owHeader->owHere = _ofPartitionOffset + sizeof(OWVariablesHeader);
-      owHeader->owTop = _ofPartitionOffset + curOffset;
-      owHeader->owNext = 0;
-      
-      owHeader->owChecksum = 0;
-      owHeader->owChecksum = ~generateOWChecksum(buffer);
-      
-      bcopy(buffer, _ofImage, _ofPartitionSize);
-    }
-    
-    IODelete(buffer, UInt8, _ofPartitionSize);
-    
-    if (!ok) return kIOReturnBadArgument;
-  }
-  
-  _ofImageDirty = false;
-  _nvramImageDirty = true;
-  
-  return kIOReturnSuccess;
+UInt8
+IODTNVRAM::calculatePartitionChecksum(UInt8 *partitionHeader)
+{
+	UInt8 cnt, isum, csum = 0;
+
+	for (cnt = 0; cnt < 0x10; cnt++) {
+		isum = csum + partitionHeader[cnt];
+		if (isum < csum) {
+			isum++;
+		}
+		csum = isum;
+	}
+
+	return csum;
+}
+
+IOReturn
+IODTNVRAM::initOFVariables(void)
+{
+	UInt32            cnt;
+	UInt8             *propName, *propData;
+	UInt32            propNameLength, propDataLength;
+	const OSSymbol    *propSymbol;
+	OSObject          *propObject;
+
+	if (_ofImage == 0) {
+		return kIOReturnNotReady;
+	}
+
+	_ofDict = OSDictionary::withCapacity(1);
+	_ofLock = IOLockAlloc();
+	if (!_ofDict || !_ofLock) {
+		return kIOReturnNoMemory;
+	}
+
+	cnt = 0;
+	while (cnt < _ofPartitionSize) {
+		// Break if there is no name.
+		if (_ofImage[cnt] == '\0') {
+			break;
+		}
+
+		// Find the length of the name.
+		propName = _ofImage + cnt;
+		for (propNameLength = 0; (cnt + propNameLength) < _ofPartitionSize;
+		    propNameLength++) {
+			if (_ofImage[cnt + propNameLength] == '=') {
+				break;
+			}
+		}
+
+		// Break if the name goes past the end of the partition.
+		if ((cnt + propNameLength) >= _ofPartitionSize) {
+			break;
+		}
+		cnt += propNameLength + 1;
+
+		propData = _ofImage + cnt;
+		for (propDataLength = 0; (cnt + propDataLength) < _ofPartitionSize;
+		    propDataLength++) {
+			if (_ofImage[cnt + propDataLength] == '\0') {
+				break;
+			}
+		}
+
+		// Break if the data goes past the end of the partition.
+		if ((cnt + propDataLength) >= _ofPartitionSize) {
+			break;
+		}
+		cnt += propDataLength + 1;
+
+		if (convertPropToObject(propName, propNameLength,
+		    propData, propDataLength,
+		    &propSymbol, &propObject)) {
+			_ofDict->setObject(propSymbol, propObject);
+			propSymbol->release();
+			propObject->release();
+		}
+	}
+
+	// Create the boot-args property if it is not in the dictionary.
+	if (_ofDict->getObject("boot-args") == 0) {
+		propObject = OSString::withCStringNoCopy("");
+		if (propObject != 0) {
+			_ofDict->setObject("boot-args", propObject);
+			propObject->release();
+		}
+	}
+
+	if (_piImage != 0) {
+		propDataLength = *(UInt32 *)_piImage;
+		if ((propDataLength != 0) && (propDataLength <= (_piPartitionSize - 4))) {
+			propObject = OSData::withBytes(_piImage + 4, propDataLength);
+			_ofDict->setObject(kIODTNVRAMPanicInfoKey, propObject);
+			propObject->release();
+
+			// Clear the length from _piImage and mark dirty.
+			*(UInt32 *)_piImage = 0;
+			if (_nvramController != 0) {
+				_nvramController->write(0, _nvramImage, kIODTNVRAMImageSize);
+			}
+		}
+	}
+
+	return kIOReturnSuccess;
+}
+
+IOReturn
+IODTNVRAM::syncOFVariables(void)
+{
+	return kIOReturnUnsupported;
+}
+
+IOReturn
+IODTNVRAM::syncVariables(void)
+{
+	bool                 ok;
+	UInt32               length, maxLength;
+	UInt8                *buffer, *tmpBuffer;
+	const OSSymbol       *tmpSymbol;
+	OSObject             *tmpObject;
+	OSCollectionIterator *iter;
+
+	IOLockAssert(_ofLock, kIOLockAssertOwned);
+
+	if ((_ofImage == 0) || (_ofDict == 0) || _systemPaniced) {
+		return kIOReturnNotReady;
+	}
+
+	buffer = tmpBuffer = IONew(UInt8, _ofPartitionSize);
+	if (buffer == 0) {
+		return kIOReturnNoMemory;
+	}
+	bzero(buffer, _ofPartitionSize);
+
+	ok = true;
+	maxLength = _ofPartitionSize;
+
+	iter = OSCollectionIterator::withCollection(_ofDict);
+	if (iter == 0) {
+		ok = false;
+	}
+
+	while (ok) {
+		tmpSymbol = OSDynamicCast(OSSymbol, iter->getNextObject());
+		if (tmpSymbol == 0) {
+			break;
+		}
+
+		// Don't save 'aapl,panic-info'.
+		if (tmpSymbol->isEqualTo(kIODTNVRAMPanicInfoKey)) {
+			continue;
+		}
+
+		tmpObject = _ofDict->getObject(tmpSymbol);
+
+		length = maxLength;
+		ok = convertObjectToProp(tmpBuffer, &length, tmpSymbol, tmpObject);
+		if (ok) {
+			tmpBuffer += length;
+			maxLength -= length;
+		}
+	}
+	iter->release();
+
+	if (ok) {
+		bcopy(buffer, _ofImage, _ofPartitionSize);
+	}
+
+	IODelete(buffer, UInt8, _ofPartitionSize);
+
+	if (!ok) {
+		return kIOReturnBadArgument;
+	}
+
+	if (_nvramController != 0) {
+		return _nvramController->write(0, _nvramImage, kIODTNVRAMImageSize);
+	}
+
+	return kIOReturnNotReady;
 }
 
 struct OFVariable {
-  const char *variableName;
-  UInt32     variableType;
-  UInt32     variablePerm;
-  SInt32     variableOffset;
+	const char *variableName;
+	UInt32     variableType;
+	UInt32     variablePerm;
+	SInt32     variableOffset;
 };
 typedef struct OFVariable OFVariable;
 
 enum {
-  kOWVariableOffsetNumber = 8,
-  kOWVariableOffsetString = 17
+	kOWVariableOffsetNumber = 8,
+	kOWVariableOffsetString = 17
 };
 
+static const
 OFVariable gOFVariables[] = {
-  {"little-endian?", kOFVariableTypeBoolean, kOFVariablePermUserRead, 0},
-  {"real-mode?", kOFVariableTypeBoolean, kOFVariablePermUserRead, 1},
-  {"auto-boot?", kOFVariableTypeBoolean, kOFVariablePermUserRead, 2},
-  {"diag-switch?", kOFVariableTypeBoolean, kOFVariablePermUserRead, 3},
-  {"fcode-debug?", kOFVariableTypeBoolean, kOFVariablePermUserRead, 4},
-  {"oem-banner?", kOFVariableTypeBoolean, kOFVariablePermUserRead, 5},
-  {"oem-logo?", kOFVariableTypeBoolean, kOFVariablePermUserRead, 6},
-  {"use-nvramrc?", kOFVariableTypeBoolean, kOFVariablePermUserRead, 7},
-  {"use-generic?", kOFVariableTypeBoolean, kOFVariablePermUserRead, -1},
-  {"default-mac-address?", kOFVariableTypeBoolean, kOFVariablePermUserRead,-1},
-  {"real-base", kOFVariableTypeNumber, kOFVariablePermUserRead, 8},
-  {"real-size", kOFVariableTypeNumber, kOFVariablePermUserRead, 9},
-  {"virt-base", kOFVariableTypeNumber, kOFVariablePermUserRead, 10},
-  {"virt-size", kOFVariableTypeNumber, kOFVariablePermUserRead, 11},
-  {"load-base", kOFVariableTypeNumber, kOFVariablePermUserRead, 12},
-  {"pci-probe-list", kOFVariableTypeNumber, kOFVariablePermUserRead, 13},
-  {"pci-probe-mask", kOFVariableTypeNumber, kOFVariablePermUserRead, -1},
-  {"screen-#columns", kOFVariableTypeNumber, kOFVariablePermUserRead, 14},
-  {"screen-#rows", kOFVariableTypeNumber, kOFVariablePermUserRead, 15},
-  {"selftest-#megs", kOFVariableTypeNumber, kOFVariablePermUserRead, 16},
-  {"boot-device", kOFVariableTypeString, kOFVariablePermUserRead, 17},
-  {"boot-file", kOFVariableTypeString, kOFVariablePermUserRead, 18},
-  {"boot-screen", kOFVariableTypeString, kOFVariablePermUserRead, -1},
-  {"console-screen", kOFVariableTypeString, kOFVariablePermUserRead, -1},
-  {"diag-device", kOFVariableTypeString, kOFVariablePermUserRead, 19},
-  {"diag-file", kOFVariableTypeString, kOFVariablePermUserRead, 20},
-  {"input-device", kOFVariableTypeString, kOFVariablePermUserRead, 21},
-  {"output-device", kOFVariableTypeString, kOFVariablePermUserRead, 22},
-  {"input-device-1", kOFVariableTypeString, kOFVariablePermUserRead, -1},
-  {"output-device-1", kOFVariableTypeString, kOFVariablePermUserRead, -1},
-  {"mouse-device", kOFVariableTypeString, kOFVariablePermUserRead, -1},
-  {"oem-banner", kOFVariableTypeString, kOFVariablePermUserRead, 23},
-  {"oem-logo", kOFVariableTypeString, kOFVariablePermUserRead, 24},
-  {"nvramrc", kOFVariableTypeString, kOFVariablePermUserRead, 25},
-  {"boot-command", kOFVariableTypeString, kOFVariablePermUserRead, 26},
-  {"default-client-ip", kOFVariableTypeString, kOFVariablePermUserRead, -1},
-  {"default-server-ip", kOFVariableTypeString, kOFVariablePermUserRead, -1},
-  {"default-gateway-ip", kOFVariableTypeString, kOFVariablePermUserRead, -1},
-  {"default-subnet-mask", kOFVariableTypeString, kOFVariablePermUserRead, -1},
-  {"default-router-ip", kOFVariableTypeString, kOFVariablePermUserRead, -1},
-  {"boot-script", kOFVariableTypeString, kOFVariablePermUserRead, -1},
-  {"boot-args", kOFVariableTypeString, kOFVariablePermUserRead, -1},
-  {"aapl,pci", kOFVariableTypeData, kOFVariablePermRootOnly, -1},
-  {"security-mode", kOFVariableTypeString, kOFVariablePermUserRead, -1},
-  {"security-password", kOFVariableTypeData, kOFVariablePermRootOnly, -1},
-  {"boot-image", kOFVariableTypeData, kOFVariablePermUserWrite, -1},
-  {0, kOFVariableTypeData, kOFVariablePermUserRead, -1}
+	{"little-endian?", kOFVariableTypeBoolean, kOFVariablePermUserRead, 0},
+	{"real-mode?", kOFVariableTypeBoolean, kOFVariablePermUserRead, 1},
+	{"auto-boot?", kOFVariableTypeBoolean, kOFVariablePermUserRead, 2},
+	{"diag-switch?", kOFVariableTypeBoolean, kOFVariablePermUserRead, 3},
+	{"fcode-debug?", kOFVariableTypeBoolean, kOFVariablePermUserRead, 4},
+	{"oem-banner?", kOFVariableTypeBoolean, kOFVariablePermUserRead, 5},
+	{"oem-logo?", kOFVariableTypeBoolean, kOFVariablePermUserRead, 6},
+	{"use-nvramrc?", kOFVariableTypeBoolean, kOFVariablePermUserRead, 7},
+	{"use-generic?", kOFVariableTypeBoolean, kOFVariablePermUserRead, -1},
+	{"default-mac-address?", kOFVariableTypeBoolean, kOFVariablePermUserRead, -1},
+	{"real-base", kOFVariableTypeNumber, kOFVariablePermUserRead, 8},
+	{"real-size", kOFVariableTypeNumber, kOFVariablePermUserRead, 9},
+	{"virt-base", kOFVariableTypeNumber, kOFVariablePermUserRead, 10},
+	{"virt-size", kOFVariableTypeNumber, kOFVariablePermUserRead, 11},
+	{"load-base", kOFVariableTypeNumber, kOFVariablePermUserRead, 12},
+	{"pci-probe-list", kOFVariableTypeNumber, kOFVariablePermUserRead, 13},
+	{"pci-probe-mask", kOFVariableTypeNumber, kOFVariablePermUserRead, -1},
+	{"screen-#columns", kOFVariableTypeNumber, kOFVariablePermUserRead, 14},
+	{"screen-#rows", kOFVariableTypeNumber, kOFVariablePermUserRead, 15},
+	{"selftest-#megs", kOFVariableTypeNumber, kOFVariablePermUserRead, 16},
+	{"boot-device", kOFVariableTypeString, kOFVariablePermUserRead, 17},
+	{"boot-file", kOFVariableTypeString, kOFVariablePermUserRead, 18},
+	{"boot-screen", kOFVariableTypeString, kOFVariablePermUserRead, -1},
+	{"console-screen", kOFVariableTypeString, kOFVariablePermUserRead, -1},
+	{"diag-device", kOFVariableTypeString, kOFVariablePermUserRead, 19},
+	{"diag-file", kOFVariableTypeString, kOFVariablePermUserRead, 20},
+	{"input-device", kOFVariableTypeString, kOFVariablePermUserRead, 21},
+	{"output-device", kOFVariableTypeString, kOFVariablePermUserRead, 22},
+	{"input-device-1", kOFVariableTypeString, kOFVariablePermUserRead, -1},
+	{"output-device-1", kOFVariableTypeString, kOFVariablePermUserRead, -1},
+	{"mouse-device", kOFVariableTypeString, kOFVariablePermUserRead, -1},
+	{"oem-banner", kOFVariableTypeString, kOFVariablePermUserRead, 23},
+	{"oem-logo", kOFVariableTypeString, kOFVariablePermUserRead, 24},
+	{"nvramrc", kOFVariableTypeString, kOFVariablePermUserRead, 25},
+	{"boot-command", kOFVariableTypeString, kOFVariablePermUserRead, 26},
+	{"default-client-ip", kOFVariableTypeString, kOFVariablePermUserRead, -1},
+	{"default-server-ip", kOFVariableTypeString, kOFVariablePermUserRead, -1},
+	{"default-gateway-ip", kOFVariableTypeString, kOFVariablePermUserRead, -1},
+	{"default-subnet-mask", kOFVariableTypeString, kOFVariablePermUserRead, -1},
+	{"default-router-ip", kOFVariableTypeString, kOFVariablePermUserRead, -1},
+	{"boot-script", kOFVariableTypeString, kOFVariablePermUserRead, -1},
+	{"boot-args", kOFVariableTypeString, kOFVariablePermUserRead, -1},
+	{"aapl,pci", kOFVariableTypeData, kOFVariablePermRootOnly, -1},
+	{"security-mode", kOFVariableTypeString, kOFVariablePermUserRead, -1},
+	{"security-password", kOFVariableTypeData, kOFVariablePermRootOnly, -1},
+	{"boot-image", kOFVariableTypeData, kOFVariablePermUserWrite, -1},
+	{"com.apple.System.fp-state", kOFVariableTypeData, kOFVariablePermKernelOnly, -1},
+#if CONFIG_EMBEDDED
+	{"backlight-level", kOFVariableTypeData, kOFVariablePermUserWrite, -1},
+	{"com.apple.System.sep.art", kOFVariableTypeData, kOFVariablePermKernelOnly, -1},
+	{"com.apple.System.boot-nonce", kOFVariableTypeString, kOFVariablePermKernelOnly, -1},
+	{"darkboot", kOFVariableTypeBoolean, kOFVariablePermUserWrite, -1},
+	{"acc-mb-ld-lifetime", kOFVariableTypeNumber, kOFVariablePermKernelOnly, -1},
+	{"acc-cm-override-charger-count", kOFVariableTypeNumber, kOFVariablePermKernelOnly, -1},
+	{"acc-cm-override-count", kOFVariableTypeNumber, kOFVariablePermKernelOnly, -1},
+	{"enter-tdm-mode", kOFVariableTypeBoolean, kOFVariablePermUserWrite, -1},
+	{"nonce-seeds", kOFVariableTypeData, kOFVariablePermKernelOnly, -1},
+#endif
+	{0, kOFVariableTypeData, kOFVariablePermUserRead, -1}
 };
 
-UInt32 IODTNVRAM::getOFVariableType(const OSSymbol *propSymbol) const
-{
-  OFVariable *ofVar;
-  
-  ofVar = gOFVariables;
-  while (1) {
-    if ((ofVar->variableName == 0) ||
-	propSymbol->isEqualTo(ofVar->variableName)) break;
-    ofVar++;
-  }
-  
-  return ofVar->variableType;
-}
-
-UInt32 IODTNVRAM::getOFVariablePerm(const OSSymbol *propSymbol) const
-{
-  OFVariable *ofVar;
-  
-  ofVar = gOFVariables;
-  while (1) {
-    if ((ofVar->variableName == 0) ||
-	propSymbol->isEqualTo(ofVar->variableName)) break;
-    ofVar++;
-  }
-  
-  return ofVar->variablePerm;
-}
-
-bool IODTNVRAM::getOWVariableInfo(UInt32 variableNumber, const OSSymbol **propSymbol,
-				  UInt32 *propType, UInt32 *propOffset)
-{
-  OFVariable *ofVar;
-  
-  ofVar = gOFVariables;
-  while (1) {
-    if (ofVar->variableName == 0) return false;
-    
-    if (ofVar->variableOffset == (SInt32) variableNumber) break;
-    
-    ofVar++;
-  }
-  
-  *propSymbol = OSSymbol::withCStringNoCopy(ofVar->variableName);
-  *propType = ofVar->variableType;
-  
-  switch (*propType) {
-  case kOFVariableTypeBoolean :
-    *propOffset = 1 << (31 - variableNumber);
-    break;
-    
-  case kOFVariableTypeNumber :
-    *propOffset = variableNumber - kOWVariableOffsetNumber;
-    break;
-    
-  case kOFVariableTypeString :
-    *propOffset = variableNumber - kOWVariableOffsetString;
-    break;
-  }
-  
-  return true;
-}
-
-bool IODTNVRAM::convertPropToObject(UInt8 *propName, UInt32 propNameLength,
-				    UInt8 *propData, UInt32 propDataLength,
-				    const OSSymbol **propSymbol,
-				    OSObject **propObject)
-{
-  UInt32         propType;
-  const OSSymbol *tmpSymbol;
-  OSObject       *tmpObject;
-  OSNumber       *tmpNumber;
-  OSString       *tmpString;
-  
-  // Create the symbol.
-  propName[propNameLength] = '\0';
-  tmpSymbol = OSSymbol::withCString((const char *)propName);
-  propName[propNameLength] = '=';
-  if (tmpSymbol == 0) {
-    return false;
-  }
-  
-  propType = getOFVariableType(tmpSymbol);
-  
-  // Create the object.
-  tmpObject = 0;
-  switch (propType) {
-  case kOFVariableTypeBoolean :
-    if (!strncmp("true", (const char *)propData, propDataLength)) {
-      tmpObject = kOSBooleanTrue;
-    } else if (!strncmp("false", (const char *)propData, propDataLength)) {
-      tmpObject = kOSBooleanFalse;
-    }
-    break;
-    
-  case kOFVariableTypeNumber :
-    tmpNumber = OSNumber::withNumber(strtol((const char *)propData, 0, 0), 32);
-    if (tmpNumber != 0) tmpObject = tmpNumber;
-    break;
-    
-  case kOFVariableTypeString :
-    tmpString = OSString::withCString((const char *)propData);
-    if (tmpString != 0) tmpObject = tmpString;
-    break;
-    
-  case kOFVariableTypeData :
-    tmpObject = unescapeBytesToData(propData, propDataLength);
-    break;
-  }
-  
-  if (tmpObject == 0) {
-    tmpSymbol->release();
-    return false;
-  }
-  
-  *propSymbol = tmpSymbol;
-  *propObject = tmpObject;
-  
-  return true;
-}
-
-bool IODTNVRAM::convertObjectToProp(UInt8 *buffer, UInt32 *length,
-				    const OSSymbol *propSymbol, OSObject *propObject)
-{
-  const UInt8    *propName;
-  UInt32         propNameLength, propDataLength;
-  UInt32         propType, tmpValue;
-  OSBoolean      *tmpBoolean = 0;
-  OSNumber       *tmpNumber = 0;
-  OSString       *tmpString = 0;
-  OSData         *tmpData = 0;
-  
-  propName = (const UInt8 *)propSymbol->getCStringNoCopy();
-  propNameLength = propSymbol->getLength();
-  propType = getOFVariableType(propSymbol);
-  
-  // Get the size of the data.
-  propDataLength = 0xFFFFFFFF;
-  switch (propType) {
-  case kOFVariableTypeBoolean :
-    tmpBoolean = OSDynamicCast(OSBoolean, propObject);
-    if (tmpBoolean != 0) propDataLength = 5;
-    break;
-    
-  case kOFVariableTypeNumber :
-    tmpNumber = OSDynamicCast(OSNumber, propObject);
-    if (tmpNumber != 0) propDataLength = 10;
-    break;
-    
-  case kOFVariableTypeString :
-    tmpString = OSDynamicCast(OSString, propObject);
-    if (tmpString != 0) propDataLength = tmpString->getLength();
-    break;
-    
-  case kOFVariableTypeData :
-    tmpData = OSDynamicCast(OSData, propObject); 
-    if (tmpData != 0) {
-      tmpData = escapeDataToData(tmpData);
-      propDataLength = tmpData->getLength();
-    }
-    break;
-  }
-  
-  // Make sure the propertySize is known and will fit.
-  if (propDataLength == 0xFFFFFFFF) return false;
-  if ((propNameLength + propDataLength + 2) > *length) return false;
-  
-  // Copy the property name equal sign.
-  sprintf((char *)buffer, "%s=", propName);
-  buffer += propNameLength + 1;
-  
-  switch (propType) {
-  case kOFVariableTypeBoolean :
-    if (tmpBoolean->getValue()) {
-      strcpy((char *)buffer, "true");
-    } else {
-      strcpy((char *)buffer, "false");
-    }
-    break;
-    
-  case kOFVariableTypeNumber :
-    tmpValue = tmpNumber->unsigned32BitValue();
-    if (tmpValue == 0xFFFFFFFF) {
-      strcpy((char *)buffer, "-1");
-    } else if (tmpValue < 1000) {
-      sprintf((char *)buffer, "%ld", tmpValue);
-    } else {
-      sprintf((char *)buffer, "0x%lx", tmpValue);
-    }
-    break;
-    
-  case kOFVariableTypeString :
-    strcpy((char *)buffer, tmpString->getCStringNoCopy());
-    break;
-    
-  case kOFVariableTypeData :
-    bcopy(tmpData->getBytesNoCopy(), buffer, propDataLength);
-    tmpData->release();
-    break;
-  }
-  
-  propDataLength = strlen((const char *)buffer);  
-  
-  *length = propNameLength + propDataLength + 2;
-  
-  return true;
-}
-
-
-UInt16 IODTNVRAM::generateOWChecksum(UInt8 *buffer)
-{
-  UInt32 cnt, checksum = 0;
-  UInt16 *tmpBuffer = (UInt16 *)buffer;
-  
-  for (cnt = 0; cnt < _ofPartitionSize / 2; cnt++)
-    checksum += tmpBuffer[cnt];
-  
-  return checksum % 0x0000FFFF;
-}
-
-bool IODTNVRAM::validateOWChecksum(UInt8 *buffer)
-{
-  UInt32 cnt, checksum, sum = 0;
-  UInt16 *tmpBuffer = (UInt16 *)buffer;
-  
-  for (cnt = 0; cnt < _ofPartitionSize / 2; cnt++)
-    sum += tmpBuffer[cnt];
-  
-  checksum = (sum >> 16) + (sum & 0x0000FFFF);
-  if (checksum == 0x10000) checksum--;
-  checksum = (checksum ^ 0x0000FFFF) & 0x0000FFFF;
-  
-  return checksum == 0;
-}
-
-void IODTNVRAM::updateOWBootArgs(const OSSymbol *key, OSObject *value)
-{
-  bool        wasBootArgs, bootr = false;
-  UInt32      cnt;
-  OSString    *tmpString, *bootCommand, *bootArgs = 0;
-  const UInt8 *bootCommandData, *bootArgsData;
-  UInt8       *tmpData;
-  UInt32      bootCommandDataLength, bootArgsDataLength, tmpDataLength;
-  
-  tmpString = OSDynamicCast(OSString, value);
-  if (tmpString == 0) return;
-  
-  if (key->isEqualTo("boot-command")) {
-    wasBootArgs = false;
-    bootCommand = tmpString;
-  } else if (key->isEqualTo("boot-args")) {
-    wasBootArgs = true;
-    bootArgs = tmpString;
-    bootCommand = OSDynamicCast(OSString, _ofDict->getObject("boot-command"));
-    if (bootCommand == 0) return;
-  } else return;
-  
-  bootCommandData = (const UInt8 *)bootCommand->getCStringNoCopy();
-  bootCommandDataLength = bootCommand->getLength();
-  
-  if (bootCommandData == 0) return;
-  
-  for (cnt = 0; cnt < bootCommandDataLength; cnt++) {
-    if ((bootCommandData[cnt] == 'b') &&
-	!strncmp("bootr", (const char *)bootCommandData + cnt, 5)) {
-      cnt += 5;
-      while (bootCommandData[cnt] == ' ') cnt++;
-      bootr = true;
-      break;
-    }
-  }
-  if (!bootr) {
-    _ofDict->removeObject("boot-args");
-    return;
-  }
-  
-  if (wasBootArgs) {
-    bootArgsData = (const UInt8 *)bootArgs->getCStringNoCopy();
-    bootArgsDataLength = bootArgs->getLength();
-    if (bootArgsData == 0) return;
-    
-    tmpDataLength = cnt + bootArgsDataLength;
-    tmpData = IONew(UInt8, tmpDataLength + 1);
-    if (tmpData == 0) return;
-    
-    strncpy((char *)tmpData, (const char *)bootCommandData, cnt);
-    tmpData[cnt] = '\0';
-    strcat((char *)tmpData, (const char *)bootArgsData);
-    
-    bootCommand = OSString::withCString((const char *)tmpData);
-    if (bootCommand != 0) {
-      _ofDict->setObject("boot-command", bootCommand);
-      bootCommand->release();
-    }
-    
-    IODelete(tmpData, UInt8, tmpDataLength + 1);
-  } else {
-    bootArgs = OSString::withCString((const char *)(bootCommandData + cnt));
-    if (bootArgs != 0) {
-      _ofDict->setObject("boot-args", bootArgs);
-      bootArgs->release();
-    }
-  }
-}
-
-
-// Private methods for Name Registry access.
-
-enum {
-  kMaxNVNameLength = 4,
-  kMaxNVDataLength = 8
-};
-
-#pragma options align=mac68k
-struct NVRAMProperty
-{
-  IONVRAMDescriptor   header;
-  UInt8               nameLength;
-  UInt8               name[ kMaxNVNameLength ];
-  UInt8               dataLength;
-  UInt8               data[ kMaxNVDataLength ];
-};
-#pragma options align=reset
-
-bool IODTNVRAM::searchNVRAMProperty(IONVRAMDescriptor *hdr, UInt32 *where)
-{
-  UInt32 offset;
-  SInt32 nvEnd;
-  
-  nvEnd = *((UInt16 *)_nrImage);
-  if(getPlatform()->getBootROMType()) {
-    // on NewWorld, offset to partition start
-    nvEnd -= 0x100;
-  } else {
-    // on old world, absolute
-    nvEnd -= _nrPartitionOffset;
-  }
-  if((nvEnd < 0) || (nvEnd >= kIODTNVRAMNameRegistrySize))
-    nvEnd = 2;
-  
-  offset = 2;
-  while ((offset + sizeof(NVRAMProperty)) <= (UInt32)nvEnd) {
-    if (bcmp(_nrImage + offset, hdr, sizeof(*hdr)) == 0) {
-      *where = offset;
-      return true;
-    }
-    offset += sizeof(NVRAMProperty);
-  }
-  
-  if ((nvEnd + sizeof(NVRAMProperty)) <= kIODTNVRAMNameRegistrySize)
-    *where = nvEnd;
-  else
-    *where = 0;
-  
-  return false;
-}
-
-IOReturn IODTNVRAM::readNVRAMPropertyType0(IORegistryEntry *entry,
-					   const OSSymbol **name,
-					   OSData **value)
-{
-  IONVRAMDescriptor hdr;
-  NVRAMProperty     *prop;
-  IOByteCount       length;
-  UInt32            offset;
-  IOReturn          err;
-  char              nameBuf[kMaxNVNameLength + 1];
-  
-  if (_nrImage == 0) return kIOReturnUnsupported;
-  if ((entry == 0) || (name == 0) || (value == 0)) return kIOReturnBadArgument;
-  
-  err = IODTMakeNVDescriptor(entry, &hdr);
-  if (err != kIOReturnSuccess) return err;
-  
-  if (searchNVRAMProperty(&hdr, &offset)) {
-    prop = (NVRAMProperty *)(_nrImage + offset);
-    
-    length = prop->nameLength;
-    if (length > kMaxNVNameLength) length = kMaxNVNameLength;
-    strncpy(nameBuf, (const char *)prop->name, length);
-    nameBuf[length] = 0;
-    *name = OSSymbol::withCString(nameBuf);
-    
-    length = prop->dataLength;
-    if (length > kMaxNVDataLength) length = kMaxNVDataLength;
-    *value = OSData::withBytes(prop->data, length);
-    
-    if ((*name != 0) && (*value != 0)) return kIOReturnSuccess;
-    else return kIOReturnNoMemory;
-  }
-  
-  return kIOReturnNoResources;
-}
-
-IOReturn IODTNVRAM::writeNVRAMPropertyType0(IORegistryEntry *entry,
-					    const OSSymbol *name,
-					    OSData *value)
-{
-  IONVRAMDescriptor hdr;
-  NVRAMProperty     *prop;
-  IOByteCount       nameLength;
-  IOByteCount       dataLength;
-  UInt32            offset;
-  IOReturn          err;
-  UInt16            nvLength;
-  bool              exists;
-  
-  if (_nrImage == 0) return kIOReturnUnsupported;
-  if ((entry == 0) || (name == 0) || (value == 0)) return kIOReturnBadArgument;
-  
-  nameLength = name->getLength();
-  dataLength = value->getLength();
-  if (nameLength > kMaxNVNameLength) return kIOReturnNoSpace;
-  if (dataLength > kMaxNVDataLength) return kIOReturnNoSpace;
-  
-  err = IODTMakeNVDescriptor(entry, &hdr);
-  if (err != kIOReturnSuccess) return err;
-  
-  exists = searchNVRAMProperty(&hdr, &offset);
-  if (offset == 0) return kIOReturnNoMemory;
-  
-  prop = (NVRAMProperty *)(_nrImage + offset);
-  if (!exists) bcopy(&hdr, &prop->header, sizeof(hdr));
-  
-  prop->nameLength = nameLength;
-  bcopy(name->getCStringNoCopy(), prop->name, nameLength);
-  prop->dataLength = dataLength;
-  bcopy(value->getBytesNoCopy(), prop->data, dataLength);
-  
-  if (!exists) {
-    nvLength = offset + sizeof(NVRAMProperty);
-    if (getPlatform()->getBootROMType())
-      nvLength += 0x100;
-    else
-      nvLength += _nrPartitionOffset;
-    *((UInt16 *)_nrImage) = nvLength;
-  }
-  
-  _nvramImageDirty = true;
-  
-  return err;
-}
-
-OSData *IODTNVRAM::unescapeBytesToData(const UInt8 *bytes, UInt32 length)
-{
-  OSData *data = 0;
-  UInt32 totalLength = 0;
-  UInt32 cnt, cnt2;
-  UInt8  byte;
-  bool   ok;
-
-  // Calculate the actual length of the data.
-  ok = true;
-  totalLength = 0;
-  for (cnt = 0; cnt < length;) {
-    byte = bytes[cnt++];
-    if (byte == 0xFF) {
-      byte = bytes[cnt++];
-      if (byte == 0x00) {
-        ok = false;
-        break;
-      }
-      cnt2 = byte & 0x7F;
-    } else
-      cnt2 = 1;
-    totalLength += cnt2;
-  }
-
-  if (ok) {
-    // Create an empty OSData of the correct size.
-    data = OSData::withCapacity(totalLength);
-    if (data != 0) {
-      for (cnt = 0; cnt < length;) {
-        byte = bytes[cnt++];
-        if (byte == 0xFF) {
-          byte = bytes[cnt++];
-          cnt2 = byte & 0x7F;
-          byte = (byte & 0x80) ? 0xFF : 0x00;
-        } else
-          cnt2 = 1;
-        data->appendByte(byte, cnt2);
-      }
-    }
-  }
-
-  return data;
-}
-
-OSData * IODTNVRAM::escapeDataToData(OSData * value)
-{
-  OSData *       result;
-  const UInt8 *  startPtr;
-  const UInt8 *  endPtr;
-  const UInt8 *  wherePtr;
-  UInt8          byte;
-  bool	         ok = true;
-
-  wherePtr = (const UInt8 *) value->getBytesNoCopy();
-  endPtr = wherePtr + value->getLength();
-
-  result = OSData::withCapacity(endPtr - wherePtr);
-  if (!result)
-    return result;
-
-  while (wherePtr < endPtr) {
-    startPtr = wherePtr;
-    byte = *wherePtr++;
-    if ((byte == 0x00) || (byte == 0xFF)) {
-      for (;
-            ((wherePtr - startPtr) < 0x80) && (wherePtr < endPtr) && (byte == *wherePtr);
-            wherePtr++)	{}
-      ok &= result->appendByte(0xff, 1);
-      byte = (byte & 0x80) | (wherePtr - startPtr);
-    }
-    ok &= result->appendByte(byte, 1);
-  }
-  ok &= result->appendByte(0, 1);
-
-  if (!ok) {
-    result->release();
-    result = 0;
-  }
-
-  return result;
-}
-
-static bool IsApplePropertyName(const char * propName)
-{
-  char c;
-  while ((c = *propName++)) {
-    if ((c >= 'A') && (c <= 'Z'))
-      break;
-  }
-
-  return (c == 0);
-}
-
-IOReturn IODTNVRAM::readNVRAMPropertyType1(IORegistryEntry *entry,
-					   const OSSymbol **name,
-					   OSData **value)
-{
-  IOReturn    err = kIOReturnNoResources;
-  OSData      *data;
-  const UInt8 *startPtr;
-  const UInt8 *endPtr;
-  const UInt8 *wherePtr;
-  const UInt8 *nvPath = 0;
-  const char  *nvName = 0;
-  const char  *resultName = 0;
-  const UInt8 *resultValue = 0;
-  UInt32       resultValueLen = 0;
-  UInt8       byte;
-
-  if (_ofDict == 0) return err;
-  data = OSDynamicCast(OSData, _ofDict->getObject(_registryPropertiesKey));
-  if (data == 0) return err;
-  
-  startPtr = (const UInt8 *) data->getBytesNoCopy();
-  endPtr = startPtr + data->getLength();
-
-  wherePtr = startPtr;
-  while (wherePtr < endPtr) {
-    byte = *(wherePtr++);
-    if (byte)
-      continue;
-    
-    if (nvPath == 0)
-      nvPath = startPtr;
-    else if (nvName == 0)
-      nvName = (const char *) startPtr;
-    else {
-      IORegistryEntry * compareEntry = IORegistryEntry::fromPath((const char *) nvPath, gIODTPlane);
-      if (compareEntry)
-        compareEntry->release();
-      if (entry == compareEntry) {
-        bool appleProp = IsApplePropertyName(nvName);
-        if (!appleProp || !resultName) {
-          resultName     = nvName;
-          resultValue    = startPtr;
-          resultValueLen = wherePtr - startPtr - 1;
-        }
-        if (!appleProp)
-          break;
-      }
-      nvPath = 0;
-      nvName = 0;
-    }
-    startPtr = wherePtr;
-  }
-  if (resultName) {
-    *name = OSSymbol::withCString(resultName);
-    *value = unescapeBytesToData(resultValue, resultValueLen);
-    if ((*name != 0) && (*value != 0))
-      err = kIOReturnSuccess;
-    else
-      err = kIOReturnNoMemory;
-  }
-  return err;
-}
-
-IOReturn IODTNVRAM::writeNVRAMPropertyType1(IORegistryEntry *entry,
-					    const OSSymbol *propName,
-					    OSData *value)
-{
-  OSData       *oldData;
-  OSData       *data = 0;
-  const UInt8  *startPtr;
-  const UInt8  *propStart;
-  const UInt8  *endPtr;
-  const UInt8  *wherePtr;
-  const UInt8  *nvPath = 0;
-  const char   *nvName = 0;
-  const char * comp;
-  const char * name;
-  UInt8        byte;
-  bool         ok = true;
-  bool         settingAppleProp;
-
-  if (_ofDict == 0) return kIOReturnNoResources;
-
-  settingAppleProp = IsApplePropertyName(propName->getCStringNoCopy());
-
-  // copy over existing properties for other entries
-
-  oldData = OSDynamicCast(OSData, _ofDict->getObject(_registryPropertiesKey));
-  if (oldData) {
-    startPtr = (const UInt8 *) oldData->getBytesNoCopy();
-    endPtr = startPtr + oldData->getLength();
-    
-    propStart = startPtr;
-    wherePtr = startPtr;
-    while (wherePtr < endPtr) {
-      byte = *(wherePtr++);
-      if (byte)
-        continue;
-      if (nvPath == 0)
-        nvPath = startPtr;
-      else if (nvName == 0)
-        nvName = (const char *) startPtr;
-      else {
-        IORegistryEntry * compareEntry = IORegistryEntry::fromPath((const char *) nvPath, gIODTPlane);
-        if (compareEntry)
-          compareEntry->release();
-        if (entry == compareEntry) {
-          if ((settingAppleProp && propName->isEqualTo(nvName))
-           || (!settingAppleProp && !IsApplePropertyName(nvName))) {
-             // delete old property (nvPath -> wherePtr)
-             data = OSData::withBytes(propStart, nvPath - propStart);
-             if (data)
-               ok &= data->appendBytes(wherePtr, endPtr - wherePtr);
-             break;
-          }
-        }
-        nvPath = 0;
-        nvName = 0;
-      }
-        
-      startPtr = wherePtr;
-    }
-  }
-
-  // make the new property
-
-  if (!data) {
-    if (oldData)
-      data = OSData::withData(oldData);
-    else
-      data = OSData::withCapacity(16);
-    if (!data)
-      return kIOReturnNoMemory;
-  }
-
-  if (value && value->getLength()) {
-		// get entries in path
-		OSArray *array = OSArray::withCapacity(5);
-		if (!array) {
-			data->release();
-			return kIOReturnNoMemory;
-		}
-		do
-			array->setObject(entry);
-		while ((entry = entry->getParentEntry(gIODTPlane)));
-
-		// append path
-		for (int i = array->getCount() - 3;
-					(entry = (IORegistryEntry *) array->getObject(i));
-					i--) {
-
-			name = entry->getName(gIODTPlane);
-			comp = entry->getLocation(gIODTPlane);
-			if( comp && (0 == strcmp("pci", name))
-			 && (0 == strcmp("80000000", comp))) {
-				// yosemite hack
-				comp = "/pci@80000000";
+UInt32
+IODTNVRAM::getOFVariableType(const OSSymbol *propSymbol) const
+{
+	const OFVariable *ofVar;
+
+	ofVar = gOFVariables;
+	while (1) {
+		if ((ofVar->variableName == 0) ||
+		    propSymbol->isEqualTo(ofVar->variableName)) {
+			break;
+		}
+		ofVar++;
+	}
+
+	return ofVar->variableType;
+}
+
+UInt32
+IODTNVRAM::getOFVariablePerm(const OSSymbol *propSymbol) const
+{
+	const OFVariable *ofVar;
+
+	ofVar = gOFVariables;
+	while (1) {
+		if ((ofVar->variableName == 0) ||
+		    propSymbol->isEqualTo(ofVar->variableName)) {
+			break;
+		}
+		ofVar++;
+	}
+
+	return ofVar->variablePerm;
+}
+
+bool
+IODTNVRAM::getOWVariableInfo(UInt32 variableNumber, const OSSymbol **propSymbol,
+    UInt32 *propType, UInt32 *propOffset)
+{
+	const OFVariable *ofVar;
+
+	ofVar = gOFVariables;
+	while (1) {
+		if (ofVar->variableName == 0) {
+			return false;
+		}
+
+		if (ofVar->variableOffset == (SInt32) variableNumber) {
+			break;
+		}
+
+		ofVar++;
+	}
+
+	*propSymbol = OSSymbol::withCStringNoCopy(ofVar->variableName);
+	*propType = ofVar->variableType;
+
+	switch (*propType) {
+	case kOFVariableTypeBoolean:
+		*propOffset = 1 << (31 - variableNumber);
+		break;
+
+	case kOFVariableTypeNumber:
+		*propOffset = variableNumber - kOWVariableOffsetNumber;
+		break;
+
+	case kOFVariableTypeString:
+		*propOffset = variableNumber - kOWVariableOffsetString;
+		break;
+	}
+
+	return true;
+}
+
+bool
+IODTNVRAM::convertPropToObject(UInt8 *propName, UInt32 propNameLength,
+    UInt8 *propData, UInt32 propDataLength,
+    const OSSymbol **propSymbol,
+    OSObject **propObject)
+{
+	UInt32         propType;
+	const OSSymbol *tmpSymbol;
+	OSObject       *tmpObject;
+	OSNumber       *tmpNumber;
+	OSString       *tmpString;
+
+	// Create the symbol.
+	propName[propNameLength] = '\0';
+	tmpSymbol = OSSymbol::withCString((const char *)propName);
+	propName[propNameLength] = '=';
+	if (tmpSymbol == 0) {
+		return false;
+	}
+
+	propType = getOFVariableType(tmpSymbol);
+
+	// Create the object.
+	tmpObject = 0;
+	switch (propType) {
+	case kOFVariableTypeBoolean:
+		if (!strncmp("true", (const char *)propData, propDataLength)) {
+			tmpObject = kOSBooleanTrue;
+		} else if (!strncmp("false", (const char *)propData, propDataLength)) {
+			tmpObject = kOSBooleanFalse;
+		}
+		break;
+
+	case kOFVariableTypeNumber:
+		tmpNumber = OSNumber::withNumber(strtol((const char *)propData, 0, 0), 32);
+		if (tmpNumber != 0) {
+			tmpObject = tmpNumber;
+		}
+		break;
+
+	case kOFVariableTypeString:
+		tmpString = OSString::withCString((const char *)propData);
+		if (tmpString != 0) {
+			tmpObject = tmpString;
+		}
+		break;
+
+	case kOFVariableTypeData:
+		tmpObject = unescapeBytesToData(propData, propDataLength);
+		break;
+	}
+
+	if (tmpObject == 0) {
+		tmpSymbol->release();
+		return false;
+	}
+
+	*propSymbol = tmpSymbol;
+	*propObject = tmpObject;
+
+	return true;
+}
+
+bool
+IODTNVRAM::convertObjectToProp(UInt8 *buffer, UInt32 *length,
+    const OSSymbol *propSymbol, OSObject *propObject)
+{
+	const UInt8    *propName;
+	UInt32         propNameLength, propDataLength, remaining;
+	UInt32         propType, tmpValue;
+	OSBoolean      *tmpBoolean = 0;
+	OSNumber       *tmpNumber = 0;
+	OSString       *tmpString = 0;
+	OSData         *tmpData = 0;
+
+	propName = (const UInt8 *)propSymbol->getCStringNoCopy();
+	propNameLength = propSymbol->getLength();
+	propType = getOFVariableType(propSymbol);
+
+	// Get the size of the data.
+	propDataLength = 0xFFFFFFFF;
+	switch (propType) {
+	case kOFVariableTypeBoolean:
+		tmpBoolean = OSDynamicCast(OSBoolean, propObject);
+		if (tmpBoolean != 0) {
+			propDataLength = 5;
+		}
+		break;
+
+	case kOFVariableTypeNumber:
+		tmpNumber = OSDynamicCast(OSNumber, propObject);
+		if (tmpNumber != 0) {
+			propDataLength = 10;
+		}
+		break;
+
+	case kOFVariableTypeString:
+		tmpString = OSDynamicCast(OSString, propObject);
+		if (tmpString != 0) {
+			propDataLength = tmpString->getLength();
+		}
+		break;
+
+	case kOFVariableTypeData:
+		tmpData = OSDynamicCast(OSData, propObject);
+		if (tmpData != 0) {
+			tmpData = escapeDataToData(tmpData);
+			propDataLength = tmpData->getLength();
+		}
+		break;
+	}
+
+	// Make sure the propertySize is known and will fit.
+	if (propDataLength == 0xFFFFFFFF) {
+		return false;
+	}
+	if ((propNameLength + propDataLength + 2) > *length) {
+		return false;
+	}
+
+	// Copy the property name equal sign.
+	buffer += snprintf((char *)buffer, *length, "%s=", propName);
+	remaining = *length - propNameLength - 1;
+
+	switch (propType) {
+	case kOFVariableTypeBoolean:
+		if (tmpBoolean->getValue()) {
+			strlcpy((char *)buffer, "true", remaining);
+		} else {
+			strlcpy((char *)buffer, "false", remaining);
+		}
+		break;
+
+	case kOFVariableTypeNumber:
+		tmpValue = tmpNumber->unsigned32BitValue();
+		if (tmpValue == 0xFFFFFFFF) {
+			strlcpy((char *)buffer, "-1", remaining);
+		} else if (tmpValue < 1000) {
+			snprintf((char *)buffer, remaining, "%d", (uint32_t)tmpValue);
+		} else {
+			snprintf((char *)buffer, remaining, "0x%x", (uint32_t)tmpValue);
+		}
+		break;
+
+	case kOFVariableTypeString:
+		strlcpy((char *)buffer, tmpString->getCStringNoCopy(), remaining);
+		break;
+
+	case kOFVariableTypeData:
+		bcopy(tmpData->getBytesNoCopy(), buffer, propDataLength);
+		tmpData->release();
+		break;
+	}
+
+	propDataLength = strlen((const char *)buffer);
+
+	*length = propNameLength + propDataLength + 2;
+
+	return true;
+}
+
+
+UInt16
+IODTNVRAM::generateOWChecksum(UInt8 *buffer)
+{
+	UInt32 cnt, checksum = 0;
+	UInt16 *tmpBuffer = (UInt16 *)buffer;
+
+	for (cnt = 0; cnt < _ofPartitionSize / 2; cnt++) {
+		checksum += tmpBuffer[cnt];
+	}
+
+	return checksum % 0x0000FFFF;
+}
+
+bool
+IODTNVRAM::validateOWChecksum(UInt8 *buffer)
+{
+	UInt32 cnt, checksum, sum = 0;
+	UInt16 *tmpBuffer = (UInt16 *)buffer;
+
+	for (cnt = 0; cnt < _ofPartitionSize / 2; cnt++) {
+		sum += tmpBuffer[cnt];
+	}
+
+	checksum = (sum >> 16) + (sum & 0x0000FFFF);
+	if (checksum == 0x10000) {
+		checksum--;
+	}
+	checksum = (checksum ^ 0x0000FFFF) & 0x0000FFFF;
+
+	return checksum == 0;
+}
+
+void
+IODTNVRAM::updateOWBootArgs(const OSSymbol *key, OSObject *value)
+{
+	bool        wasBootArgs, bootr = false;
+	UInt32      cnt;
+	OSString    *tmpString, *bootCommand, *bootArgs = 0;
+	const UInt8 *bootCommandData, *bootArgsData;
+	UInt8       *tmpData;
+	UInt32      bootCommandDataLength, bootArgsDataLength, tmpDataLength;
+
+	tmpString = OSDynamicCast(OSString, value);
+	if (tmpString == 0) {
+		return;
+	}
+
+	if (key->isEqualTo("boot-command")) {
+		wasBootArgs = false;
+		bootCommand = tmpString;
+	} else if (key->isEqualTo("boot-args")) {
+		wasBootArgs = true;
+		bootArgs = tmpString;
+		bootCommand = OSDynamicCast(OSString, _ofDict->getObject("boot-command"));
+		if (bootCommand == 0) {
+			return;
+		}
+	} else {
+		return;
+	}
+
+	bootCommandData = (const UInt8 *)bootCommand->getCStringNoCopy();
+	bootCommandDataLength = bootCommand->getLength();
+
+	if (bootCommandData == 0) {
+		return;
+	}
+
+	for (cnt = 0; cnt < bootCommandDataLength; cnt++) {
+		if ((bootCommandData[cnt] == 'b') &&
+		    !strncmp("bootr", (const char *)bootCommandData + cnt, 5)) {
+			cnt += 5;
+			while (bootCommandData[cnt] == ' ') {
+				cnt++;
+			}
+			bootr = true;
+			break;
+		}
+	}
+	if (!bootr) {
+		_ofDict->removeObject("boot-args");
+		return;
+	}
+
+	if (wasBootArgs) {
+		bootArgsData = (const UInt8 *)bootArgs->getCStringNoCopy();
+		bootArgsDataLength = bootArgs->getLength();
+		if (bootArgsData == 0) {
+			return;
+		}
+
+		tmpDataLength = cnt + bootArgsDataLength;
+		tmpData = IONew(UInt8, tmpDataLength + 1);
+		if (tmpData == 0) {
+			return;
+		}
+
+		cnt -= strlcpy((char *)tmpData, (const char *)bootCommandData, cnt);
+		strlcat((char *)tmpData, (const char *)bootArgsData, cnt);
+
+		bootCommand = OSString::withCString((const char *)tmpData);
+		if (bootCommand != 0) {
+			_ofDict->setObject("boot-command", bootCommand);
+			bootCommand->release();
+		}
+
+		IODelete(tmpData, UInt8, tmpDataLength + 1);
+	} else {
+		bootArgs = OSString::withCString((const char *)(bootCommandData + cnt));
+		if (bootArgs != 0) {
+			_ofDict->setObject("boot-args", bootArgs);
+			bootArgs->release();
+		}
+	}
+}
+
+bool
+IODTNVRAM::searchNVRAMProperty(IONVRAMDescriptor *hdr, UInt32 *where)
+{
+	return false;
+}
+
+IOReturn
+IODTNVRAM::readNVRAMPropertyType0(IORegistryEntry *entry,
+    const OSSymbol **name,
+    OSData **value)
+{
+	return kIOReturnUnsupported;
+}
+
+
+IOReturn
+IODTNVRAM::writeNVRAMPropertyType0(IORegistryEntry *entry,
+    const OSSymbol *name,
+    OSData *value)
+{
+	return kIOReturnUnsupported;
+}
+
+
+OSData *
+IODTNVRAM::unescapeBytesToData(const UInt8 *bytes, UInt32 length)
+{
+	OSData *data = 0;
+	UInt32 totalLength = 0;
+	UInt32 cnt, cnt2;
+	UInt8  byte;
+	bool   ok;
+
+	// Calculate the actual length of the data.
+	ok = true;
+	totalLength = 0;
+	for (cnt = 0; cnt < length;) {
+		byte = bytes[cnt++];
+		if (byte == 0xFF) {
+			byte = bytes[cnt++];
+			if (byte == 0x00) {
+				ok = false;
+				break;
+			}
+			cnt2 = byte & 0x7F;
+		} else {
+			cnt2 = 1;
+		}
+		totalLength += cnt2;
+	}
+
+	if (ok) {
+		// Create an empty OSData of the correct size.
+		data = OSData::withCapacity(totalLength);
+		if (data != 0) {
+			for (cnt = 0; cnt < length;) {
+				byte = bytes[cnt++];
+				if (byte == 0xFF) {
+					byte = bytes[cnt++];
+					cnt2 = byte & 0x7F;
+					byte = (byte & 0x80) ? 0xFF : 0x00;
+				} else {
+					cnt2 = 1;
+				}
+				data->appendByte(byte, cnt2);
+			}
+		}
+	}
+
+	return data;
+}
+
+OSData *
+IODTNVRAM::escapeDataToData(OSData * value)
+{
+	OSData *       result;
+	const UInt8 *  startPtr;
+	const UInt8 *  endPtr;
+	const UInt8 *  wherePtr;
+	UInt8          byte;
+	bool           ok = true;
+
+	wherePtr = (const UInt8 *) value->getBytesNoCopy();
+	endPtr = wherePtr + value->getLength();
+
+	result = OSData::withCapacity(endPtr - wherePtr);
+	if (!result) {
+		return result;
+	}
+
+	while (wherePtr < endPtr) {
+		startPtr = wherePtr;
+		byte = *wherePtr++;
+		if ((byte == 0x00) || (byte == 0xFF)) {
+			for (;
+			    ((wherePtr - startPtr) < 0x80) && (wherePtr < endPtr) && (byte == *wherePtr);
+			    wherePtr++) {
+			}
+			ok &= result->appendByte(0xff, 1);
+			byte = (byte & 0x80) | (wherePtr - startPtr);
+		}
+		ok &= result->appendByte(byte, 1);
+	}
+	ok &= result->appendByte(0, 1);
+
+	if (!ok) {
+		result->release();
+		result = 0;
+	}
+
+	return result;
+}
+
+static bool
+IsApplePropertyName(const char * propName)
+{
+	char c;
+	while ((c = *propName++)) {
+		if ((c >= 'A') && (c <= 'Z')) {
+			break;
+		}
+	}
+
+	return c == 0;
+}
+
+IOReturn
+IODTNVRAM::readNVRAMPropertyType1(IORegistryEntry *entry,
+    const OSSymbol **name,
+    OSData **value)
+{
+	IOReturn    err = kIOReturnNoResources;
+	OSData      *data;
+	const UInt8 *startPtr;
+	const UInt8 *endPtr;
+	const UInt8 *wherePtr;
+	const UInt8 *nvPath = 0;
+	const char  *nvName = 0;
+	const char  *resultName = 0;
+	const UInt8 *resultValue = 0;
+	UInt32       resultValueLen = 0;
+	UInt8       byte;
+
+	if (_ofDict == 0) {
+		return err;
+	}
+
+	IOLockLock(_ofLock);
+	data = OSDynamicCast(OSData, _ofDict->getObject(_registryPropertiesKey));
+	IOLockUnlock(_ofLock);
+
+	if (data == 0) {
+		return err;
+	}
+
+	startPtr = (const UInt8 *) data->getBytesNoCopy();
+	endPtr = startPtr + data->getLength();
+
+	wherePtr = startPtr;
+	while (wherePtr < endPtr) {
+		byte = *(wherePtr++);
+		if (byte) {
+			continue;
+		}
+
+		if (nvPath == 0) {
+			nvPath = startPtr;
+		} else if (nvName == 0) {
+			nvName = (const char *) startPtr;
+		} else {
+			IORegistryEntry * compareEntry = IORegistryEntry::fromPath((const char *) nvPath, gIODTPlane);
+			if (compareEntry) {
+				compareEntry->release();
+			}
+			if (entry == compareEntry) {
+				bool appleProp = IsApplePropertyName(nvName);
+				if (!appleProp || !resultName) {
+					resultName     = nvName;
+					resultValue    = startPtr;
+					resultValueLen = wherePtr - startPtr - 1;
+				}
+				if (!appleProp) {
+					break;
+				}
+			}
+			nvPath = 0;
+			nvName = 0;
+		}
+		startPtr = wherePtr;
+	}
+	if (resultName) {
+		*name = OSSymbol::withCString(resultName);
+		*value = unescapeBytesToData(resultValue, resultValueLen);
+		if ((*name != 0) && (*value != 0)) {
+			err = kIOReturnSuccess;
+		} else {
+			err = kIOReturnNoMemory;
+		}
+	}
+	return err;
+}
+
+IOReturn
+IODTNVRAM::writeNVRAMPropertyType1(IORegistryEntry *entry,
+    const OSSymbol *propName,
+    OSData *value)
+{
+	OSData       *oldData, *escapedData;
+	OSData       *data = 0;
+	const UInt8  *startPtr;
+	const UInt8  *propStart;
+	const UInt8  *endPtr;
+	const UInt8  *wherePtr;
+	const UInt8  *nvPath = 0;
+	const char   *nvName = 0;
+	const char * comp;
+	const char * name;
+	UInt8        byte;
+	bool         ok = true;
+	bool         settingAppleProp;
+
+	if (_ofDict == 0) {
+		return kIOReturnNoResources;
+	}
+
+	settingAppleProp = IsApplePropertyName(propName->getCStringNoCopy());
+
+	// copy over existing properties for other entries
+
+	IOLockLock(_ofLock);
+
+	oldData = OSDynamicCast(OSData, _ofDict->getObject(_registryPropertiesKey));
+	if (oldData) {
+		startPtr = (const UInt8 *) oldData->getBytesNoCopy();
+		endPtr = startPtr + oldData->getLength();
+
+		propStart = startPtr;
+		wherePtr = startPtr;
+		while (wherePtr < endPtr) {
+			byte = *(wherePtr++);
+			if (byte) {
+				continue;
+			}
+			if (nvPath == 0) {
+				nvPath = startPtr;
+			} else if (nvName == 0) {
+				nvName = (const char *) startPtr;
 			} else {
-				if (comp)
+				IORegistryEntry * compareEntry = IORegistryEntry::fromPath((const char *) nvPath, gIODTPlane);
+				if (compareEntry) {
+					compareEntry->release();
+				}
+				if (entry == compareEntry) {
+					if ((settingAppleProp && propName->isEqualTo(nvName))
+					    || (!settingAppleProp && !IsApplePropertyName(nvName))) {
+						// delete old property (nvPath -> wherePtr)
+						data = OSData::withBytes(propStart, nvPath - propStart);
+						if (data) {
+							ok &= data->appendBytes(wherePtr, endPtr - wherePtr);
+						}
+						break;
+					}
+				}
+				nvPath = 0;
+				nvName = 0;
+			}
+
+			startPtr = wherePtr;
+		}
+	}
+
+	// make the new property
+
+	if (!data) {
+		if (oldData) {
+			data = OSData::withData(oldData);
+		} else {
+			data = OSData::withCapacity(16);
+		}
+		if (!data) {
+			ok = false;
+		}
+	}
+
+	if (ok && value && value->getLength()) {
+		do {
+			// get entries in path
+			OSArray *array = OSArray::withCapacity(5);
+			if (!array) {
+				ok = false;
+				break;
+			}
+			do{
+				array->setObject(entry);
+			} while ((entry = entry->getParentEntry(gIODTPlane)));
+
+			// append path
+			for (int i = array->getCount() - 3;
+			    (entry = (IORegistryEntry *) array->getObject(i));
+			    i--) {
+				name = entry->getName(gIODTPlane);
+				comp = entry->getLocation(gIODTPlane);
+				if (comp) {
 					ok &= data->appendBytes("/@", 2);
-				else {
-					if (!name)
+				} else {
+					if (!name) {
 						continue;
+					}
 					ok &= data->appendByte('/', 1);
 					comp = name;
 				}
-			}
-			ok &= data->appendBytes(comp, strlen(comp));
-		}
-		ok &= data->appendByte(0, 1);
-		array->release();
-
-		// append prop name
-		ok &= data->appendBytes(propName->getCStringNoCopy(), propName->getLength() + 1);
-		
-		// append escaped data
-		oldData = escapeDataToData(value);
-		ok &= (oldData != 0);
-		if (ok)
-			ok &= data->appendBytes(oldData);
-	}
-  if (ok) {
-    ok = _ofDict->setObject(_registryPropertiesKey, data);
-    if (ok)
-      _ofImageDirty = true;
-  }
-  data->release();
-
-  return ok ? kIOReturnSuccess : kIOReturnNoMemory;
-}
+				ok &= data->appendBytes(comp, strlen(comp));
+			}
+			ok &= data->appendByte(0, 1);
+			array->release();
+
+			// append prop name
+			ok &= data->appendBytes(propName->getCStringNoCopy(), propName->getLength() + 1);
+
+			// append escaped data
+			escapedData = escapeDataToData(value);
+			ok &= (escapedData != 0);
+			if (ok) {
+				ok &= data->appendBytes(escapedData);
+			}
+		} while (false);
+	}
+
+	oldData->retain();
+	if (ok) {
+		ok = _ofDict->setObject(_registryPropertiesKey, data);
+	}
+
+	if (data) {
+		data->release();
+	}
+
+	if (ok) {
+		if (syncVariables() != kIOReturnSuccess) {
+			if (oldData) {
+				_ofDict->setObject(_registryPropertiesKey, oldData);
+			} else {
+				_ofDict->removeObject(_registryPropertiesKey);
+			}
+			(void) syncVariables();
+			ok = false;
+		}
+	}
+
+	if (oldData) {
+		oldData->release();
+	}
+
+	IOLockUnlock(_ofLock);
+
+	return ok ? kIOReturnSuccess : kIOReturnNoMemory;
+}
+
+bool
+IODTNVRAM::safeToSync(void)
+{
+	AbsoluteTime delta;
+	UInt64       delta_ns;
+	SInt32       delta_secs;
+
+	// delta interval went by
+	clock_get_uptime(&delta);
+
+	// Figure it in seconds.
+	absolutetime_to_nanoseconds(delta, &delta_ns);
+	delta_secs = (SInt32)(delta_ns / NSEC_PER_SEC);
+
+	if ((delta_secs > (_lastDeviceSync + MIN_SYNC_NOW_INTERVAL)) || _freshInterval) {
+		_lastDeviceSync = delta_secs;
+		_freshInterval = FALSE;
+		return TRUE;
+	}
+
+	return FALSE;
+}