added README

added QEMU files
removed personal artifacts

QemuFwCfgLib.c

@@ -0,0 +1,298 @@
+/** @file
+
+  Copyright (c) 2011 - 2013, Intel Corporation. All rights reserved.<BR>
+  Copyright (C) 2013, Red Hat, Inc.
+  Copyright (c) 2017, AMD Incorporated. 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.
+
+**/
+
+#include <Uefi.h>
+#include <Library/BaseLib.h>
+#include <Library/BaseMemoryLib.h>
+#include <Library/DebugLib.h>
+#include <Library/IoLib.h>
+#include <Library/QemuFwCfgLib.h>
+#include <Library/MemoryAllocationLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+
+#include "QemuFwCfgLibInternal.h"
+
+
+/**
+  Selects a firmware configuration item for reading.
+  
+  Following this call, any data read from this item will start from
+  the beginning of the configuration item's data.
+
+  @param[in] QemuFwCfgItem - Firmware Configuration item to read
+
+**/
+VOID
+EFIAPI
+QemuFwCfgSelectItem (
+  IN FIRMWARE_CONFIG_ITEM   QemuFwCfgItem
+  )
+{
+  DEBUG ((EFI_D_INFO, "Select Item: 0x%x\n", (UINT16)(UINTN) QemuFwCfgItem));
+  IoWrite16 (FW_CFG_IO_SELECTOR, (UINT16)(UINTN) QemuFwCfgItem);
+}
+
+/**
+  Reads firmware configuration bytes into a buffer
+
+  @param[in] Size - Size in bytes to read
+  @param[in] Buffer - Buffer to store data into  (OPTIONAL if Size is 0)
+
+**/
+VOID
+EFIAPI
+InternalQemuFwCfgReadBytes (
+  IN UINTN                  Size,
+  IN VOID                   *Buffer  OPTIONAL
+  )
+{
+  if (InternalQemuFwCfgDmaIsAvailable () && Size <= MAX_UINT32) {
+    InternalQemuFwCfgDmaBytes ((UINT32)Size, Buffer, FW_CFG_DMA_CTL_READ);
+    return;
+  }
+  IoReadFifo8 (FW_CFG_IO_DATA, Size, Buffer);
+}
+
+
+/**
+  Reads firmware configuration bytes into a buffer
+
+  If called multiple times, then the data read will
+  continue at the offset of the firmware configuration
+  item where the previous read ended.
+
+  @param[in] Size - Size in bytes to read
+  @param[in] Buffer - Buffer to store data into
+
+**/
+VOID
+EFIAPI
+QemuFwCfgReadBytes (
+  IN UINTN                  Size,
+  IN VOID                   *Buffer
+  )
+{
+  if (InternalQemuFwCfgIsAvailable ()) {
+    InternalQemuFwCfgReadBytes (Size, Buffer);
+  } else {
+    ZeroMem (Buffer, Size);
+  }
+}
+
+/**
+  Write firmware configuration bytes from a buffer
+
+  If called multiple times, then the data written will
+  continue at the offset of the firmware configuration
+  item where the previous write ended.
+
+  @param[in] Size - Size in bytes to write
+  @param[in] Buffer - Buffer to read data from
+
+**/
+VOID
+EFIAPI
+QemuFwCfgWriteBytes (
+  IN UINTN                  Size,
+  IN VOID                   *Buffer
+  )
+{
+  if (InternalQemuFwCfgIsAvailable ()) {
+    if (InternalQemuFwCfgDmaIsAvailable () && Size <= MAX_UINT32) {
+      InternalQemuFwCfgDmaBytes ((UINT32)Size, Buffer, FW_CFG_DMA_CTL_WRITE);
+      return;
+    }
+    IoWriteFifo8 (FW_CFG_IO_DATA, Size, Buffer);
+  }
+}
+
+
+/**
+  Skip bytes in the firmware configuration item.
+
+  Increase the offset of the firmware configuration item without transferring
+  bytes between the item and a caller-provided buffer. Subsequent read, write
+  or skip operations will commence at the increased offset.
+
+  @param[in] Size  Number of bytes to skip.
+**/
+VOID
+EFIAPI
+QemuFwCfgSkipBytes (
+  IN UINTN                  Size
+  )
+{
+  UINTN ChunkSize;
+  UINT8 SkipBuffer[256];
+
+  if (!InternalQemuFwCfgIsAvailable ()) {
+    return;
+  }
+
+  if (InternalQemuFwCfgDmaIsAvailable () && Size <= MAX_UINT32) {
+    InternalQemuFwCfgDmaBytes ((UINT32)Size, NULL, FW_CFG_DMA_CTL_SKIP);
+    return;
+  }
+
+  //
+  // Emulate the skip by reading data in chunks, and throwing it away. The
+  // implementation below is suitable even for phases where RAM or dynamic
+  // allocation is not available or appropriate. It also doesn't affect the
+  // static data footprint for client modules. Large skips are not expected,
+  // therefore this fallback is not performance critical. The size of
+  // SkipBuffer is thought not to exert a large pressure on the stack in any
+  // phase.
+  //
+  while (Size > 0) {
+    ChunkSize = MIN (Size, sizeof SkipBuffer);
+    IoReadFifo8 (FW_CFG_IO_DATA, ChunkSize, SkipBuffer);
+    Size -= ChunkSize;
+  }
+}
+
+
+/**
+  Reads a UINT8 firmware configuration value
+
+  @return    Value of Firmware Configuration item read
+
+**/
+UINT8
+EFIAPI
+QemuFwCfgRead8 (
+  VOID
+  )
+{
+  UINT8 Result;
+
+  QemuFwCfgReadBytes (sizeof (Result), &Result);
+
+  return Result;
+}
+
+
+/**
+  Reads a UINT16 firmware configuration value
+
+  @return    Value of Firmware Configuration item read
+
+**/
+UINT16
+EFIAPI
+QemuFwCfgRead16 (
+  VOID
+  )
+{
+  UINT16 Result;
+
+  QemuFwCfgReadBytes (sizeof (Result), &Result);
+
+  return Result;
+}
+
+
+/**
+  Reads a UINT32 firmware configuration value
+
+  @return    Value of Firmware Configuration item read
+
+**/
+UINT32
+EFIAPI
+QemuFwCfgRead32 (
+  VOID
+  )
+{
+  UINT32 Result;
+
+  QemuFwCfgReadBytes (sizeof (Result), &Result);
+
+  return Result;
+}
+
+
+/**
+  Reads a UINT64 firmware configuration value
+
+  @return    Value of Firmware Configuration item read
+
+**/
+UINT64
+EFIAPI
+QemuFwCfgRead64 (
+  VOID
+  )
+{
+  UINT64 Result;
+
+  QemuFwCfgReadBytes (sizeof (Result), &Result);
+
+  return Result;
+}
+
+
+/**
+  Find the configuration item corresponding to the firmware configuration file.
+
+  @param[in]  Name - Name of file to look up.
+  @param[out] Item - Configuration item corresponding to the file, to be passed
+                     to QemuFwCfgSelectItem ().
+  @param[out] Size - Number of bytes in the file.
+
+  @return    RETURN_SUCCESS       If file is found.
+             RETURN_NOT_FOUND     If file is not found.
+             RETURN_UNSUPPORTED   If firmware configuration is unavailable.
+
+**/
+RETURN_STATUS
+EFIAPI
+QemuFwCfgFindFile (
+  IN   CONST CHAR8           *Name,
+  OUT  FIRMWARE_CONFIG_ITEM  *Item,
+  OUT  UINTN                 *Size
+  )
+{
+  UINT32 Count;
+  UINT32 Idx;
+
+  if (!InternalQemuFwCfgIsAvailable ()) {
+    return RETURN_UNSUPPORTED;
+  }
+
+  QemuFwCfgSelectItem (QemuFwCfgItemFileDir);
+  Count = SwapBytes32 (QemuFwCfgRead32 ());
+
+  for (Idx = 0; Idx < Count; ++Idx) {
+    UINT32 FileSize;
+    UINT16 FileSelect;
+    UINT16 FileReserved;
+    CHAR8  FName[QEMU_FW_CFG_FNAME_SIZE];
+
+    FileSize     = QemuFwCfgRead32 ();
+    FileSelect   = QemuFwCfgRead16 ();
+    FileReserved = QemuFwCfgRead16 ();
+    (VOID) FileReserved; /* Force a do-nothing reference. */
+    InternalQemuFwCfgReadBytes (sizeof (FName), FName);
+
+    if (AsciiStrCmp (Name, FName) == 0) {
+      *Item = SwapBytes16 (FileSelect);
+      *Size = SwapBytes32 (FileSize);
+      return RETURN_SUCCESS;
+    }
+  }
+
+  return RETURN_NOT_FOUND;
+}