1 files changed, 75 insertions, 0 deletions
diff --git a/ArmPkg/Library/ArmLib/AArch64/AArch64PeiLibConstructor.c b/ArmPkg/Library/ArmLib/AArch64/AArch64PeiLibConstructor.c
new file mode 100644
index 0000000000..2de9c7c54e
--- /dev/null
+++ b/ArmPkg/Library/ArmLib/AArch64/AArch64PeiLibConstructor.c
@@ -0,0 +1,75 @@
+#/* @file
+#
+#  Copyright (c) 2016, Linaro Limited. All rights reserved.
+#
+#  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 <Base.h>
+
+#include <Library/ArmLib.h>
+#include <Library/CacheMaintenanceLib.h>
+#include <Library/DebugLib.h>
+
+//
+// This is a hack. We define a weak symbol with external linkage, which may or
+// may not be overridden by a non-weak alternative that is defined with a non
+// zero value in the object that contains the MMU routines. Since static
+// libraries are pulled in on a per-object basis, and since the MMU object will
+// only be pulled in if any of its other symbols are referenced by the client
+// module, we can use the value below to figure out whether the MMU routines are
+// in use by this module, and decide whether cache maintenance of the function
+// ArmReplaceLiveTranslationEntry () is required.
+//
+INT32 __attribute__((weak)) HaveMmuRoutines;
+
+EFI_STATUS
+EFIAPI
+AArch64LibConstructor (
+  IN       EFI_PEI_FILE_HANDLE       FileHandle,
+  IN CONST EFI_PEI_SERVICES          **PeiServices
+  )
+{
+  extern UINT32             ArmReplaceLiveTranslationEntrySize;
+
+  EFI_FV_FILE_INFO          FileInfo;
+  EFI_STATUS                Status;
+
+  if (HaveMmuRoutines == 0) {
+    return RETURN_SUCCESS;
+  }
+
+  ASSERT (FileHandle != NULL);
+
+  Status = (*PeiServices)->FfsGetFileInfo (FileHandle, &FileInfo);
+  ASSERT_EFI_ERROR (Status);
+
+  //
+  // Some platforms do not cope very well with cache maintenance being
+  // performed on regions backed by NOR flash. Since the cache maintenance
+  // is unnecessary to begin with in that case, perform it only when not
+  // executing in place.
+  //
+  if ((UINTN)FileInfo.Buffer <= (UINTN)ArmReplaceLiveTranslationEntry &&
+      ((UINTN)FileInfo.Buffer + FileInfo.BufferSize >=
+       (UINTN)ArmReplaceLiveTranslationEntry + ArmReplaceLiveTranslationEntrySize)) {
+    DEBUG ((EFI_D_INFO, "ArmLib: skipping cache maintence on XIP PEIM\n"));
+  } else {
+    DEBUG ((EFI_D_INFO, "ArmLib: performing cache maintence on shadowed PEIM\n"));
+    //
+    // The ArmReplaceLiveTranslationEntry () helper function may be invoked
+    // with the MMU off so we have to ensure that it gets cleaned to the PoC
+    //
+    WriteBackDataCacheRange (ArmReplaceLiveTranslationEntry,
+      ArmReplaceLiveTranslationEntrySize);
+  }
+
+  return RETURN_SUCCESS;
+}