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UefiRuntimeLib.h File Reference

Functions

BOOLEAN EFIAPI EfiAtRuntime (VOID)
 
BOOLEAN EFIAPI EfiGoneVirtual (VOID)
 
EFI_STATUS EFIAPI EfiGetTime (OUT EFI_TIME *Time, OUT EFI_TIME_CAPABILITIES *Capabilities)
 
EFI_STATUS EFIAPI EfiSetTime (IN EFI_TIME *Time)
 
EFI_STATUS EFIAPI EfiGetWakeupTime (OUT BOOLEAN *Enabled, OUT BOOLEAN *Pending, OUT EFI_TIME *Time)
 
EFI_STATUS EFIAPI EfiSetWakeupTime (IN BOOLEAN Enable, IN EFI_TIME *Time)
 
EFI_STATUS EFIAPI EfiGetVariable (IN CHAR16 *VariableName, IN EFI_GUID *VendorGuid, OUT UINT32 *Attributes, IN OUT UINTN *DataSize, OUT VOID *Data)
 
EFI_STATUS EFIAPI EfiGetNextVariableName (IN OUT UINTN *VariableNameSize, IN OUT CHAR16 *VariableName, IN OUT EFI_GUID *VendorGuid)
 
EFI_STATUS EFIAPI EfiSetVariable (IN CHAR16 *VariableName, IN EFI_GUID *VendorGuid, IN UINT32 Attributes, IN UINTN DataSize, IN VOID *Data)
 
EFI_STATUS EFIAPI EfiGetNextHighMonotonicCount (OUT UINT32 *HighCount)
 
VOID EFIAPI EfiResetSystem (IN EFI_RESET_TYPE ResetType, IN EFI_STATUS ResetStatus, IN UINTN DataSize, IN VOID *ResetData)
 
EFI_STATUS EFIAPI EfiConvertPointer (IN UINTN DebugDisposition, IN OUT VOID **Address)
 
EFI_STATUS EFIAPI EfiConvertFunctionPointer (IN UINTN DebugDisposition, IN OUT VOID **Address)
 
EFI_STATUS EFIAPI EfiSetVirtualAddressMap (IN UINTN MemoryMapSize, IN UINTN DescriptorSize, IN UINT32 DescriptorVersion, IN CONST EFI_MEMORY_DESCRIPTOR *VirtualMap)
 
EFI_STATUS EFIAPI EfiConvertList (IN UINTN DebugDisposition, IN OUT LIST_ENTRY *ListHead)
 
EFI_STATUS EFIAPI EfiUpdateCapsule (IN EFI_CAPSULE_HEADER **CapsuleHeaderArray, IN UINTN CapsuleCount, IN EFI_PHYSICAL_ADDRESS ScatterGatherList)
 
EFI_STATUS EFIAPI EfiQueryCapsuleCapabilities (IN EFI_CAPSULE_HEADER **CapsuleHeaderArray, IN UINTN CapsuleCount, OUT UINT64 *MaximumCapsuleSize, OUT EFI_RESET_TYPE *ResetType)
 
EFI_STATUS EFIAPI EfiQueryVariableInfo (IN UINT32 Attributes, OUT UINT64 *MaximumVariableStorageSize, OUT UINT64 *RemainingVariableStorageSize, OUT UINT64 *MaximumVariableSize)
 

Detailed Description

Provides library functions for each of the UEFI Runtime Services. Only available to DXE and UEFI module types.

Copyright (c) 2006 - 2018, Intel Corporation. All rights reserved.
SPDX-License-Identifier: BSD-2-Clause-Patent

Function Documentation

BOOLEAN EFIAPI EfiAtRuntime ( VOID  )

This function allows the caller to determine if UEFI ExitBootServices() has been called.

This function returns TRUE after all the EVT_SIGNAL_EXIT_BOOT_SERVICES functions have executed as a result of the OS calling ExitBootServices(). Prior to this time FALSE is returned. This function is used by runtime code to decide it is legal to access services that go away after ExitBootServices().

Return values
TRUEThe system has finished executing the EVT_SIGNAL_EXIT_BOOT_SERVICES event.
FALSEThe system has not finished executing the EVT_SIGNAL_EXIT_BOOT_SERVICES event.
EFI_STATUS EFIAPI EfiConvertFunctionPointer ( IN UINTN  DebugDisposition,
IN OUT VOID **  Address 
)

Determines the new virtual address that is to be used on subsequent memory accesses.

For IA32, x64, and EBC, this service is a wrapper for the UEFI Runtime Service ConvertPointer(). See the UEFI Specification for details. For IPF, this function interprets Address as a pointer to an EFI_PLABEL structure and both the EntryPoint and GP fields of an EFI_PLABEL are converted from physical to virtiual addressing. Since IPF allows the GP to point to an address outside a PE/COFF image, the physical to virtual offset for the EntryPoint field is used to adjust the GP field. The UEFI Runtime Service ConvertPointer() is used to convert EntryPoint and the status code for this conversion is always returned. If the convertion of EntryPoint fails, then neither EntryPoint nor GP are modified. See the UEFI Specification for details on the UEFI Runtime Service ConvertPointer().

Parameters
DebugDispositionSupplies type information for the pointer being converted.
AddressThe pointer to a pointer that is to be fixed to be the value needed for the new virtual address mapping being applied.
Returns
EFI_STATUS value from EfiConvertPointer().
EFI_STATUS EFIAPI EfiConvertList ( IN UINTN  DebugDisposition,
IN OUT LIST_ENTRY ListHead 
)

Convert the standard Lib double linked list to a virtual mapping.

This service uses EfiConvertPointer() to walk a double linked list and convert all the link pointers to their virtual mappings. This function is only guaranteed to work during the EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE event and calling it at other times has undefined results.

Parameters
DebugDispositionSupplies type information for the pointer being converted.
ListHeadHead of linked list to convert.
Return values
EFI_SUCCESSSuccessfully executed the function.
!EFI_SUCCESSFailed to execute the function.
EFI_STATUS EFIAPI EfiConvertPointer ( IN UINTN  DebugDisposition,
IN OUT VOID **  Address 
)

This service is a wrapper for the UEFI Runtime Service ConvertPointer().

The ConvertPointer() function is used by an EFI component during the SetVirtualAddressMap() operation. ConvertPointer()must be called using physical address pointers during the execution of SetVirtualAddressMap().

Parameters
DebugDispositionSupplies type information for the pointer being converted.
AddressThe pointer to a pointer that is to be fixed to be the value needed for the new virtual address mapping being applied.
Return values
EFI_SUCCESSThe pointer pointed to by Address was modified.
EFI_NOT_FOUNDThe pointer pointed to by Address was not found to be part of the current memory map. This is normally fatal.
EFI_INVALID_PARAMETERAddress is NULL.
EFI_INVALID_PARAMETER*Address is NULL and DebugDispositio
EFI_STATUS EFIAPI EfiGetNextHighMonotonicCount ( OUT UINT32 HighCount)

This service is a wrapper for the UEFI Runtime Service GetNextHighMonotonicCount().

The platform's monotonic counter is comprised of two 32-bit quantities: the high 32 bits and the low 32 bits. During boot service time the low 32-bit value is volatile: it is reset to zero on every system reset and is increased by 1 on every call to GetNextMonotonicCount(). The high 32-bit value is nonvolatile and is increased by 1 whenever the system resets or whenever the low 32-bit count (returned by GetNextMonoticCount()) overflows.

Parameters
HighCountPointer to returned value.
Return values
EFI_SUCCESSThe next high monotonic count was returned.
EFI_DEVICE_ERRORThe device is not functioning properly.
EFI_INVALID_PARAMETERHighCount is NULL.
EFI_STATUS EFIAPI EfiGetNextVariableName ( IN OUT UINTN VariableNameSize,
IN OUT CHAR16 VariableName,
IN OUT EFI_GUID VendorGuid 
)

This service is a wrapper for the UEFI Runtime Service GetNextVariableName().

GetNextVariableName() is called multiple times to retrieve the VariableName and VendorGuid of all variables currently available in the system. On each call to GetNextVariableName() the previous results are passed into the interface, and on output the interface returns the next variable name data. When the entire variable list has been returned, the error EFI_NOT_FOUND is returned.

Parameters
VariableNameSizeAs input, point to maximum size of variable name. As output, point to actual size of variable name.
VariableNameAs input, supplies the last VariableName that was returned by GetNextVariableName(). As output, returns the name of variable. The name string is Null-Terminated Unicode string.
VendorGuidAs input, supplies the last VendorGuid that was returned by GetNextVriableName(). As output, returns the VendorGuid of the current variable.
Return values
EFI_SUCCESSThe function completed successfully.
EFI_NOT_FOUNDThe next variable was not found.
EFI_BUFFER_TOO_SMALLThe VariableNameSize is too small for the result. VariableNameSize has been updated with the size needed to complete the request.
EFI_INVALID_PARAMETERVariableNameSize is NULL.
EFI_INVALID_PARAMETERVariableName is NULL.
EFI_INVALID_PARAMETERVendorGuid is NULL.
EFI_DEVICE_ERRORThe variable name could not be retrieved due to a hardware error.
EFI_STATUS EFIAPI EfiGetTime ( OUT EFI_TIME Time,
OUT EFI_TIME_CAPABILITIES Capabilities 
)

This service is a wrapper for the UEFI Runtime Service GetTime().

The GetTime() function returns a time that was valid sometime during the call to the function. While the returned EFI_TIME structure contains TimeZone and Daylight savings time information, the actual clock does not maintain these values. The current time zone and daylight saving time information returned by GetTime() are the values that were last set via SetTime(). The GetTime() function should take approximately the same amount of time to read the time each time it is called. All reported device capabilities are to be rounded up. During runtime, if a PC-AT CMOS device is present in the platform, the caller must synchronize access to the device before calling GetTime().

Parameters
TimeA pointer to storage to receive a snapshot of the current time.
CapabilitiesAn optional pointer to a buffer to receive the real time clock device's capabilities.
Return values
EFI_SUCCESSThe operation completed successfully.
EFI_INVALID_PARAMETERTime is NULL.
EFI_DEVICE_ERRORThe time could not be retrieved due to a hardware error.
EFI_STATUS EFIAPI EfiGetVariable ( IN CHAR16 VariableName,
IN EFI_GUID VendorGuid,
OUT UINT32 Attributes,
IN OUT UINTN DataSize,
OUT VOID Data 
)

This service is a wrapper for the UEFI Runtime Service GetVariable().

Each vendor may create and manage its own variables without the risk of name conflicts by using a unique VendorGuid. When a variable is set, its Attributes are supplied to indicate how the data variable should be stored and maintained by the system. The attributes affect when the variable may be accessed and volatility of the data. Any attempts to access a variable that does not have the attribute set for runtime access will yield the EFI_NOT_FOUND error. If the Data buffer is too small to hold the contents of the variable, the error EFI_BUFFER_TOO_SMALL is returned and DataSize is set to the required buffer size to obtain the data.

Parameters
VariableNamethe name of the vendor's variable, it's a Null-Terminated Unicode String
VendorGuidUnify identifier for vendor.
AttributesPoint to memory location to return the attributes of variable. If the point is NULL, the parameter would be ignored.
DataSizeAs input, point to the maximum size of return Data-Buffer. As output, point to the actual size of the returned Data-Buffer.
DataPoint to return Data-Buffer.
Return values
EFI_SUCCESSThe function completed successfully.
EFI_NOT_FOUNDThe variable was not found.
EFI_BUFFER_TOO_SMALLThe DataSize is too small for the result. DataSize has been updated with the size needed to complete the request.
EFI_INVALID_PARAMETERVariableName is NULL.
EFI_INVALID_PARAMETERVendorGuid is NULL.
EFI_INVALID_PARAMETERDataSize is NULL.
EFI_INVALID_PARAMETERThe DataSize is not too small and Data is NULL.
EFI_DEVICE_ERRORThe variable could not be retrieved due to a hardware error.
EFI_SECURITY_VIOLATIONThe variable could not be retrieved due to an authentication failure.
EFI_STATUS EFIAPI EfiGetWakeupTime ( OUT BOOLEAN Enabled,
OUT BOOLEAN Pending,
OUT EFI_TIME Time 
)

This service is a wrapper for the UEFI Runtime Service GetWakeupTime().

The alarm clock time may be rounded from the set alarm clock time to be within the resolution of the alarm clock device. The resolution of the alarm clock device is defined to be one second. During runtime, if a PC-AT CMOS device is present in the platform the caller must synchronize access to the device before calling GetWakeupTime().

Parameters
EnabledIndicates if the alarm is currently enabled or disabled.
PendingIndicates if the alarm signal is pending and requires acknowledgement.
TimeThe current alarm setting. Type EFI_TIME is defined in the GetTime() function description.
Return values
EFI_SUCCESSThe alarm settings were returned.
EFI_INVALID_PARAMETEREnabled is NULL.
EFI_INVALID_PARAMETERPending is NULL.
EFI_INVALID_PARAMETERTime is NULL.
EFI_DEVICE_ERRORThe wakeup time could not be retrieved due to a hardware error.
EFI_UNSUPPORTEDA wakeup timer is not supported on this platform.
BOOLEAN EFIAPI EfiGoneVirtual ( VOID  )

This function allows the caller to determine if UEFI SetVirtualAddressMap() has been called.

This function returns TRUE after all the EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE functions have executed as a result of the OS calling SetVirtualAddressMap(). Prior to this time FALSE is returned. This function is used by runtime code to decide it is legal to access services that go away after SetVirtualAddressMap().

Return values
TRUEThe system has finished executing the EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE event.
FALSEThe system has not finished executing the EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE event.
EFI_STATUS EFIAPI EfiQueryCapsuleCapabilities ( IN EFI_CAPSULE_HEADER **  CapsuleHeaderArray,
IN UINTN  CapsuleCount,
OUT UINT64 MaximumCapsuleSize,
OUT EFI_RESET_TYPE ResetType 
)

This service is a wrapper for the UEFI Runtime Service QueryCapsuleCapabilities().

The QueryCapsuleCapabilities() function allows a caller to test to see if a capsule or capsules can be updated via UpdateCapsule(). The Flags values in the capsule header and size of the entire capsule is checked. If the caller needs to query for generic capsule capability a fake EFI_CAPSULE_HEADER can be constructed where CapsuleImageSize is equal to HeaderSize that is equal to sizeof (EFI_CAPSULE_HEADER). To determine reset requirements, CAPSULE_FLAGS_PERSIST_ACROSS_RESET should be set in the Flags field of the EFI_CAPSULE_HEADER. The firmware must support any capsule that has the CAPSULE_FLAGS_PERSIST_ACROSS_RESET flag set in EFI_CAPSULE_HEADER. The firmware sets the policy for what capsules are supported that do not have the CAPSULE_FLAGS_PERSIST_ACROSS_RESET flag set.

Parameters
CapsuleHeaderArrayVirtual pointer to an array of virtual pointers to the capsules being passed into update capsule. The capsules are assumed to stored in contiguous virtual memory.
CapsuleCountNumber of pointers to EFI_CAPSULE_HEADER in CaspuleHeaderArray.
MaximumCapsuleSizeOn output the maximum size that UpdateCapsule() can support as an argument to UpdateCapsule() via CapsuleHeaderArray and ScatterGatherList. Undefined on input.
ResetTypeReturns the type of reset required for the capsule update.
Return values
EFI_SUCCESSA valid answer was returned.
EFI_INVALID_PARAMETERMaximumCapsuleSize is NULL.
EFI_UNSUPPORTEDThe capsule type is not supported on this platform, and MaximumCapsuleSize and ResetType are undefined.
EFI_OUT_OF_RESOURCESThere were insufficient resources to process the query request.
EFI_STATUS EFIAPI EfiQueryVariableInfo ( IN UINT32  Attributes,
OUT UINT64 MaximumVariableStorageSize,
OUT UINT64 RemainingVariableStorageSize,
OUT UINT64 MaximumVariableSize 
)

This service is a wrapper for the UEFI Runtime Service QueryVariableInfo().

The QueryVariableInfo() function allows a caller to obtain the information about the maximum size of the storage space available for the EFI variables, the remaining size of the storage space available for the EFI variables and the maximum size of each individual EFI variable, associated with the attributes specified. The returned MaximumVariableStorageSize, RemainingVariableStorageSize, MaximumVariableSize information may change immediately after the call based on other runtime activities including asynchronous error events. Also, these values associated with different attributes are not additive in nature.

Parameters
AttributesAttributes bitmask to specify the type of variables on which to return information. Refer to the GetVariable() function description.
MaximumVariableStorageSizeOn output the maximum size of the storage space available for the EFI variables associated with the attributes specified.
RemainingVariableStorageSizeReturns the remaining size of the storage space available for the EFI variables associated with the attributes specified.
MaximumVariableSizeReturns the maximum size of the individual EFI variables associated with the attributes specified.
Return values
EFI_SUCCESSA valid answer was returned.
EFI_INVALID_PARAMETERAn invalid combination of attribute bits was supplied.
EFI_UNSUPPORTEDEFI_UNSUPPORTED The attribute is not supported on this platform, and the MaximumVariableStorageSize, RemainingVariableStorageSize, MaximumVariableSize are undefined.
VOID EFIAPI EfiResetSystem ( IN EFI_RESET_TYPE  ResetType,
IN EFI_STATUS  ResetStatus,
IN UINTN  DataSize,
IN VOID ResetData 
)

This service is a wrapper for the UEFI Runtime Service ResetSystem().

The ResetSystem()function resets the entire platform, including all processors and devices,and reboots the system. Calling this interface with ResetType of EfiResetCold causes a system-wide reset. This sets all circuitry within the system to its initial state. This type of reset is asynchronous to system operation and operates without regard to cycle boundaries. EfiResetCold is tantamount to a system power cycle. Calling this interface with ResetType of EfiResetWarm causes a system-wide initialization. The processors are set to their initial state, and pending cycles are not corrupted. If the system does not support this reset type, then an EfiResetCold must be performed. Calling this interface with ResetType of EfiResetShutdown causes the system to enter a power state equivalent to the ACPI G2/S5 or G3 states. If the system does not support this reset type, then when the system is rebooted, it should exhibit the EfiResetCold attributes. The platform may optionally log the parameters from any non-normal reset that occurs. The ResetSystem() function does not return.

Parameters
ResetTypeThe type of reset to perform.
ResetStatusThe status code for the reset. If the system reset is part of a normal operation, the status code would be EFI_SUCCESS. If the system reset is due to some type of failure the most appropriate EFI Status code would be used.
DataSizeThesize, in bytes, of ResetData.
ResetDataFor a ResetType of EfiResetCold, EfiResetWarm, or EfiResetShutdown the data buffer starts with a Null-terminated Unicode string, optionally followed by additional binary data. The string is a description that the caller may use to further indicate the reason for the system reset. ResetData is only valid if ResetStatus is something other then EFI_SUCCESS. This pointer must be a physical address. For a ResetType of EfiResetPlatformSpecific the data buffer also starts with a Null-terminated string that is followed by an EFI_GUID that describes the specific type of reset to perform.
EFI_STATUS EFIAPI EfiSetTime ( IN EFI_TIME Time)

This service is a wrapper for the UEFI Runtime Service SetTime().

The SetTime() function sets the real time clock device to the supplied time, and records the current time zone and daylight savings time information. The SetTime() function is not allowed to loop based on the current time. For example, if the device does not support a hardware reset for the sub-resolution time, the code is not to implement the feature by waiting for the time to wrap. During runtime, if a PC-AT CMOS device is present in the platform, the caller must synchronize access to the device before calling SetTime().

Parameters
TimeA pointer to the current time. Type EFI_TIME is defined in the GetTime() function description. Full error checking is performed on the different fields of the EFI_TIME structure (refer to the EFI_TIME definition in the GetTime() function description for full details), and EFI_INVALID_PARAMETER is returned if any field is out of range.
Return values
EFI_SUCCESSThe operation completed successfully.
EFI_INVALID_PARAMETERA time field is out of range.
EFI_DEVICE_ERRORThe time could not be set due to a hardware error.
EFI_STATUS EFIAPI EfiSetVariable ( IN CHAR16 VariableName,
IN EFI_GUID VendorGuid,
IN UINT32  Attributes,
IN UINTN  DataSize,
IN VOID Data 
)

This service is a wrapper for the UEFI Runtime Service GetNextVariableName()

Variables are stored by the firmware and may maintain their values across power cycles. Each vendor may create and manage its own variables without the risk of name conflicts by using a unique VendorGuid.

Parameters
VariableNamethe name of the vendor's variable, as a Null-Terminated Unicode String
VendorGuidUnify identifier for vendor.
AttributesPoint to memory location to return the attributes of variable. If the point is NULL, the parameter would be ignored.
DataSizeThe size in bytes of Data-Buffer.
DataPoint to the content of the variable.
Return values
EFI_SUCCESSThe firmware has successfully stored the variable and its data as defined by the Attributes.
EFI_INVALID_PARAMETERAn invalid combination of attribute bits was supplied, or the DataSize exceeds the maximum allowed.
EFI_INVALID_PARAMETERVariableName is an empty Unicode string.
EFI_OUT_OF_RESOURCESNot enough storage is available to hold the variable and its data.
EFI_DEVICE_ERRORThe variable could not be saved due to a hardware failure.
EFI_WRITE_PROTECTEDThe variable in question is read-only.
EFI_WRITE_PROTECTEDThe variable in question cannot be deleted.
EFI_SECURITY_VIOLATIONThe variable could not be written due to EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS set but the AuthInfo does NOT pass the validation check carried out by the firmware.
EFI_NOT_FOUNDThe variable trying to be updated or deleted was not found.
EFI_STATUS EFIAPI EfiSetVirtualAddressMap ( IN UINTN  MemoryMapSize,
IN UINTN  DescriptorSize,
IN UINT32  DescriptorVersion,
IN CONST EFI_MEMORY_DESCRIPTOR VirtualMap 
)

This service is a wrapper for the UEFI Runtime Service SetVirtualAddressMap().

The SetVirtualAddressMap() function is used by the OS loader. The function can only be called at runtime, and is called by the owner of the system's memory map. I.e., the component which called ExitBootServices(). All events of type EVT_SIGNAL_VIRTUAL_ADDRESS_CHANGE must be signaled before SetVirtualAddressMap() returns.

Parameters
MemoryMapSizeThe size in bytes of VirtualMap.
DescriptorSizeThe size in bytes of an entry in the VirtualMap.
DescriptorVersionThe version of the structure entries in VirtualMap.
VirtualMapAn array of memory descriptors which contain new virtual address mapping information for all runtime ranges. Type EFI_MEMORY_DESCRIPTOR is defined in the GetMemoryMap() function description.
Return values
EFI_SUCCESSThe virtual address map has been applied.
EFI_UNSUPPORTEDEFI firmware is not at runtime, or the EFI firmware is already in virtual address mapped mode.
EFI_INVALID_PARAMETERDescriptorSize or DescriptorVersion is invalid.
EFI_NO_MAPPINGA virtual address was not supplied for a range in the memory map that requires a mapping.
EFI_NOT_FOUNDA virtual address was supplied for an address that is not found in the memory map.
EFI_STATUS EFIAPI EfiSetWakeupTime ( IN BOOLEAN  Enable,
IN EFI_TIME Time 
)

This service is a wrapper for the UEFI Runtime Service SetWakeupTime()

Setting a system wakeup alarm causes the system to wake up or power on at the set time. When the alarm fires, the alarm signal is latched until it is acknowledged by calling SetWakeupTime() to disable the alarm. If the alarm fires before the system is put into a sleeping or off state, since the alarm signal is latched the system will immediately wake up. If the alarm fires while the system is off and there is insufficient power to power on the system, the system is powered on when power is restored.

Parameters
EnableEnable or disable the wakeup alarm.
TimeIf Enable is TRUE, the time to set the wakeup alarm for. Type EFI_TIME is defined in the GetTime() function description. If Enable is FALSE, then this parameter is optional, and may be NULL.
Return values
EFI_SUCCESSIf Enable is TRUE, then the wakeup alarm was enabled. If Enable is FALSE, then the wakeup alarm was disabled.
EFI_INVALID_PARAMETERA time field is out of range.
EFI_DEVICE_ERRORThe wakeup time could not be set due to a hardware error.
EFI_UNSUPPORTEDA wakeup timer is not supported on this platform.
EFI_STATUS EFIAPI EfiUpdateCapsule ( IN EFI_CAPSULE_HEADER **  CapsuleHeaderArray,
IN UINTN  CapsuleCount,
IN EFI_PHYSICAL_ADDRESS  ScatterGatherList 
)

This service is a wrapper for the UEFI Runtime Service UpdateCapsule().

Passes capsules to the firmware with both virtual and physical mapping. Depending on the intended consumption, the firmware may process the capsule immediately. If the payload should persist across a system reset, the reset value returned from EFI_QueryCapsuleCapabilities must be passed into ResetSystem() and will cause the capsule to be processed by the firmware as part of the reset process.

Parameters
CapsuleHeaderArrayVirtual pointer to an array of virtual pointers to the capsules being passed into update capsule. Each capsules is assumed to stored in contiguous virtual memory. The capsules in the CapsuleHeaderArray must be the same capsules as the ScatterGatherList. The CapsuleHeaderArray must have the capsules in the same order as the ScatterGatherList.
CapsuleCountNumber of pointers to EFI_CAPSULE_HEADER in CaspuleHeaderArray.
ScatterGatherListPhysical pointer to a set of EFI_CAPSULE_BLOCK_DESCRIPTOR that describes the location in physical memory of a set of capsules. See Related Definitions for an explanation of how more than one capsule is passed via this interface. The capsules in the ScatterGatherList must be in the same order as the CapsuleHeaderArray. This parameter is only referenced if the capsules are defined to persist across system reset.
Return values
EFI_SUCCESSA valid capsule was passed. If CAPSULE_FLAGS_PERSIT_ACROSS_RESET is not set, the capsule has been successfully processed by the firmware.
EFI_INVALID_PARAMETERCapsuleSize is NULL, or an incompatible set of flags were set in the capsule header.
EFI_INVALID_PARAMETERCapsuleCount is 0
EFI_DEVICE_ERRORThe capsule update was started, but failed due to a device error.
EFI_UNSUPPORTEDThe capsule type is not supported on this platform.
EFI_OUT_OF_RESOURCESThere were insufficient resources to process the capsule.