1 files changed, 84 insertions, 0 deletions
diff --git a/roms/edk2/ArmVirtPkg/PrePi/FdtParser.c b/roms/edk2/ArmVirtPkg/PrePi/FdtParser.c
new file mode 100644
index 000000000..4754cba55
--- /dev/null
+++ b/roms/edk2/ArmVirtPkg/PrePi/FdtParser.c
@@ -0,0 +1,84 @@
+/*
+ * Copyright (c) 2015, Linaro Ltd. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-2-Clause-Patent
+ */
+
+#include <Uefi.h>
+#include <Include/libfdt.h>
+
+BOOLEAN
+FindMemnode (
+  IN  VOID    *DeviceTreeBlob,
+  OUT UINT64  *SystemMemoryBase,
+  OUT UINT64  *SystemMemorySize
+  )
+{
+  INT32         MemoryNode;
+  INT32         AddressCells;
+  INT32         SizeCells;
+  INT32         Length;
+  CONST INT32   *Prop;
+
+  if (fdt_check_header (DeviceTreeBlob) != 0) {
+    return FALSE;
+  }
+
+  //
+  // Look for a node called "memory" at the lowest level of the tree
+  //
+  MemoryNode = fdt_path_offset (DeviceTreeBlob, "/memory");
+  if (MemoryNode <= 0) {
+    return FALSE;
+  }
+
+  //
+  // Retrieve the #address-cells and #size-cells properties
+  // from the root node, or use the default if not provided.
+  //
+  AddressCells = 1;
+  SizeCells = 1;
+
+  Prop = fdt_getprop (DeviceTreeBlob, 0, "#address-cells", &Length);
+  if (Length == 4) {
+    AddressCells = fdt32_to_cpu (*Prop);
+  }
+
+  Prop = fdt_getprop (DeviceTreeBlob, 0, "#size-cells", &Length);
+  if (Length == 4) {
+    SizeCells = fdt32_to_cpu (*Prop);
+  }
+
+  //
+  // Now find the 'reg' property of the /memory node, and read the first
+  // range listed.
+  //
+  Prop = fdt_getprop (DeviceTreeBlob, MemoryNode, "reg", &Length);
+
+  if (Length < (AddressCells + SizeCells) * sizeof (INT32)) {
+    return FALSE;
+  }
+
+  *SystemMemoryBase = fdt32_to_cpu (Prop[0]);
+  if (AddressCells > 1) {
+    *SystemMemoryBase = (*SystemMemoryBase << 32) | fdt32_to_cpu (Prop[1]);
+  }
+  Prop += AddressCells;
+
+  *SystemMemorySize = fdt32_to_cpu (Prop[0]);
+  if (SizeCells > 1) {
+    *SystemMemorySize = (*SystemMemorySize << 32) | fdt32_to_cpu (Prop[1]);
+  }
+
+  return TRUE;
+}
+
+VOID
+CopyFdt (
+  IN    VOID    *FdtDest,
+  IN    VOID    *FdtSource
+  )
+{
+  fdt_pack(FdtSource);
+  CopyMem (FdtDest, FdtSource, fdt_totalsize (FdtSource));
+}