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/*++
Copyright (c) 1998 Intel Corporation
Module Name:
Abstract:
Revision History
--*/
//
// The variable store protocol interface is specific to the reference
// implementation. The initialization code adds variable store devices
// to the system, and the FW connects to the devices to provide the
// variable store interfaces through these devices.
//
//
// Variable Store Device protocol
//
#define VARIABLE_STORE_PROTOCOL \
{ 0xf088cd91, 0xa046, 0x11d2, {0x8e, 0x42, 0x0, 0xa0, 0xc9, 0x69, 0x72, 0x3b} }
INTERFACE_DECL(_EFI_VARIABLE_STORE);
typedef
EFI_STATUS
(EFIAPI *EFI_STORE_CLEAR) (
IN struct _EFI_VARIABLE_STORE *This,
IN UINTN BankNo,
IN OUT VOID *Scratch
);
typedef
EFI_STATUS
(EFIAPI *EFI_STORE_READ) (
IN struct _EFI_VARIABLE_STORE *This,
IN UINTN BankNo,
IN UINTN Offset,
IN UINTN BufferSize,
OUT VOID *Buffer
);
typedef
EFI_STATUS
(EFIAPI *EFI_STORE_UPDATE) (
IN struct _EFI_VARIABLE_STORE *This,
IN UINTN BankNo,
IN UINTN Offset,
IN UINTN BufferSize,
IN VOID *Buffer
);
typedef
EFI_STATUS
(EFIAPI *EFI_STORE_SIZE) (
IN struct _EFI_VARIABLE_STORE *This,
IN UINTN NoBanks
);
typedef
EFI_STATUS
(EFIAPI *EFI_TRANSACTION_UPDATE) (
IN struct _EFI_VARIABLE_STORE *This,
IN UINTN BankNo,
IN VOID *NewContents
);
typedef struct _EFI_VARIABLE_STORE {
//
// Number of banks and bank size
//
UINT32 Attributes;
UINT32 BankSize;
UINT32 NoBanks;
//
// Functions to access the storage banks
//
EFI_STORE_CLEAR ClearStore;
EFI_STORE_READ ReadStore;
EFI_STORE_UPDATE UpdateStore;
EFI_STORE_SIZE SizeStore OPTIONAL;
EFI_TRANSACTION_UPDATE TransactionUpdate OPTIONAL;
} EFI_VARIABLE_STORE;
//
//
// ClearStore() - A function to clear the requested storage bank. A cleared
// bank contains all "on" bits.
//
// ReadStore() - Read data from the requested store.
//
// UpdateStore() - Updates data on the requested store. The FW will only
// ever issue updates to clear bits in the store. Updates must be
// performed in LSb to MSb order of the update buffer.
//
// SizeStore() - An optional function for non-runtime stores that can be
// dynamically sized. The FW will only ever increase or decrease the store
// by 1 banksize at a time, and it is always adding or removing a bank from
// the end of the store.
//
// By default the FW will update variables and storage banks in an
// "atomic" manner by keeping 1 old copy of the data during an update,
// and recovering appropiately if the power is lost during the middle
// of an operation. To do this the FW needs to have multiple banks
// of storage dedicated to its use. If that's not possible, the driver
// can implement an atomic bank update function and the FW will allow
// 1 bank in this case. (It will allow any number of banks,
// but it won't require an "extra" bank to provide its bank transaction
// function).
//
// TransactionUpdate() - An optional function that can clear & update an
// entire bank in an "atomic" fashion. If the operation fails in the
// middle the driver is responsible for having either the previous copy
// of the bank's data or the new copy. A copy that's partially written
// is not valid as internal data settings may get lost. Supply this
// function only when needed.
//
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