OvmfPkg: Add QemuFlashFvbServicesRuntimeDxe driver

If QEMU flash is detected, this module will install
FirmwareVolumeBlock support for the QEMU flash device.

It will also set PCDs with the results that:
1. OvmfPkg/EmuVariableFvbRuntimeDxe will be disabled
2. MdeModulePkg variable services will read/write flash directly

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@14839 6f19259b-4bc3-4df7-8a09-765794883524

OvmfPkg/QemuFlashFvbServicesRuntimeDxe/QemuFlash.h

@@ -0,0 +1,89 @@
+/** @file
+  OVMF support for QEMU system firmware flash device
+
+  Copyright (c) 2009 - 2013, Intel Corporation. All rights reserved.<BR>
+  This program and the accompanying materials
+  are licensed and made available under the terms and conditions of the BSD License
+  which accompanies this distribution.  The full text of the license may be found at
+  http://opensource.org/licenses/bsd-license.php
+
+  THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+  WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+
+**/
+
+#ifndef __QEMU_FLASH_H__
+#define __QEMU_FLASH_H__
+
+#include <Protocol/FirmwareVolumeBlock.h>
+
+/**
+  Read from QEMU Flash
+
+  @param[in] Lba      The starting logical block index to read from.
+  @param[in] Offset   Offset into the block at which to begin reading.
+  @param[in] NumBytes On input, indicates the requested read size. On
+                      output, indicates the actual number of bytes read
+  @param[in] Buffer   Pointer to the buffer to read into.
+
+**/
+EFI_STATUS
+QemuFlashRead (
+  IN        EFI_LBA                              Lba,
+  IN        UINTN                                Offset,
+  IN        UINTN                                *NumBytes,
+  IN        UINT8                                *Buffer
+  );
+
+
+/**
+  Write to QEMU Flash
+
+  @param[in] Lba      The starting logical block index to write to.
+  @param[in] Offset   Offset into the block at which to begin writing.
+  @param[in] NumBytes On input, indicates the requested write size. On
+                      output, indicates the actual number of bytes written
+  @param[in] Buffer   Pointer to the data to write.
+
+**/
+EFI_STATUS
+QemuFlashWrite (
+  IN        EFI_LBA                              Lba,
+  IN        UINTN                                Offset,
+  IN        UINTN                                *NumBytes,
+  IN        UINT8                                *Buffer
+  );
+
+
+/**
+  Erase a QEMU Flash block
+
+  @param Lba    The logical block index to erase.
+
+**/
+EFI_STATUS
+QemuFlashEraseBlock (
+  IN   EFI_LBA      Lba
+  );
+
+
+/**
+  Initializes QEMU flash memory support
+
+  @retval EFI_WRITE_PROTECTED   The QEMU flash device is not present.
+  @retval EFI_SUCCESS           The QEMU flash device is supported.
+
+**/
+EFI_STATUS
+QemuFlashInitialize (
+  VOID
+  );
+
+
+VOID
+QemuFlashConvertPointers (
+  VOID
+  );
+
+#endif
+