1 files changed, 104 insertions, 0 deletions
diff --git a/roms/edk2/FatPkg/FatPei/Part.c b/roms/edk2/FatPkg/FatPei/Part.c
new file mode 100644
index 000000000..3e2ded31c
--- /dev/null
+++ b/roms/edk2/FatPkg/FatPei/Part.c
@@ -0,0 +1,104 @@
+/** @file
+  Routines supporting partition discovery and
+  logical device reading
+
+Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.<BR>
+
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include "FatLitePeim.h"
+
+/**
+  This function finds Eltorito partitions. Main algorithm
+  is ported from DXE partition driver.
+
+  @param[in]  PrivateData       The global memory map
+  @param[in]  ParentBlockDevNo  The parent block device
+
+  @retval TRUE              New partitions are detected and logical block devices
+                            are added to block device array
+  @retval FALSE             No new partitions are added
+
+**/
+BOOLEAN
+FatFindEltoritoPartitions (
+  IN  PEI_FAT_PRIVATE_DATA *PrivateData,
+  IN  UINTN                ParentBlockDevNo
+  );
+
+/**
+  This function finds Mbr partitions. Main algorithm
+  is ported from DXE partition driver.
+
+  @param[in]  PrivateData       The global memory map
+  @param[in]  ParentBlockDevNo  The parent block device
+
+  @retval TRUE              New partitions are detected and logical block devices
+                            are added to block device array
+  @retval FALSE             No new partitions are added
+
+**/
+BOOLEAN
+FatFindMbrPartitions (
+  IN  PEI_FAT_PRIVATE_DATA *PrivateData,
+  IN  UINTN                ParentBlockDevNo
+  );
+
+/**
+  This function is used for finding GPT partition on block device.
+  As follow UEFI spec we should check protective MBR first and then
+  try to check both primary/backup GPT structures.
+
+  @param[in]  PrivateData       The global memory map
+  @param[in]  ParentBlockDevNo  The parent block device
+
+  @retval TRUE              New partitions are detected and logical block devices
+                            are added to block device array
+  @retval FALSE             No new partitions are added
+
+**/
+BOOLEAN
+FatFindGptPartitions (
+  IN  PEI_FAT_PRIVATE_DATA *PrivateData,
+  IN  UINTN                ParentBlockDevNo
+  );
+
+/**
+  This function finds partitions (logical devices) in physical block devices.
+
+  @param  PrivateData       Global memory map for accessing global variables.
+
+**/
+VOID
+FatFindPartitions (
+  IN  PEI_FAT_PRIVATE_DATA  *PrivateData
+  )
+{
+  BOOLEAN Found;
+  UINTN   Index;
+
+  do {
+    Found = FALSE;
+
+    for (Index = 0; Index < PrivateData->BlockDeviceCount; Index++) {
+      if (!PrivateData->BlockDevice[Index].PartitionChecked) {
+        if (FatFindGptPartitions (PrivateData, Index)) {
+          Found = TRUE;
+          continue;
+        }
+
+        if (FatFindMbrPartitions (PrivateData, Index)) {
+          Found = TRUE;
+          continue;
+        }
+
+        if (FatFindEltoritoPartitions (PrivateData, Index)) {
+          Found = TRUE;
+          continue;
+        }
+      }
+    }
+  } while (Found && PrivateData->BlockDeviceCount <= PEI_FAT_MAX_BLOCK_DEVICE);
+}