1 files changed, 79 insertions, 0 deletions
diff --git a/ArmVirtPkg/CloudHvPlatformHasAcpiDtDxe/CloudHvHasAcpiDtDxe.c b/ArmVirtPkg/CloudHvPlatformHasAcpiDtDxe/CloudHvHasAcpiDtDxe.c
new file mode 100644
index 0000000000..4cf1d39df4
--- /dev/null
+++ b/ArmVirtPkg/CloudHvPlatformHasAcpiDtDxe/CloudHvHasAcpiDtDxe.c
@@ -0,0 +1,79 @@
+/** @file
+  Decide whether the firmware should expose an ACPI- and/or a Device Tree-based
+  hardware description to the operating system.
+
+  Copyright (c) 2021, Arm Limited. All rights reserved.<BR>
+
+  SPDX-License-Identifier: BSD-2-Clause-Patent
+**/
+
+#include <Guid/PlatformHasAcpi.h>
+#include <Guid/PlatformHasDeviceTree.h>
+#include <Library/BaseLib.h>
+#include <Library/DebugLib.h>
+#include <Library/PcdLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+
+/** Entry point for the Cloud Hypervisor PlatformHasAcpiDtDxe.
+
+  @param [in]  ImageHandle  Handle for this image.
+  @param [in]  SystemTable  Pointer to the EFI system table.
+
+  @return EFI_SUCCESS             If ACPI or Device Tree based hardware
+                                  description protocol was installed.
+  @return EFI_INVALID_PARAMETER   A parameter was invalid.
+  @return EFI_OUT_OF_RESOURCES    Insufficient resources exist to complete
+                                  the request.
+**/
+EFI_STATUS
+EFIAPI
+PlatformHasAcpiDt (
+  IN EFI_HANDLE       ImageHandle,
+  IN EFI_SYSTEM_TABLE *SystemTable
+  )
+{
+  EFI_STATUS           Status;
+
+  //
+  // If we fail to install any of the necessary protocols below, the OS will be
+  // unbootable anyway (due to lacking hardware description), so tolerate no
+  // errors here.
+  //
+  if (MAX_UINTN == MAX_UINT64 &&
+      !PcdGetBool (PcdForceNoAcpi)) {
+    Status = gBS->InstallProtocolInterface (
+                    &ImageHandle,
+                    &gEdkiiPlatformHasAcpiGuid,
+                    EFI_NATIVE_INTERFACE,
+                    NULL
+                    );
+    if (EFI_ERROR (Status)) {
+      goto Failed;
+    }
+
+    return Status;
+  }
+
+  //
+  // Expose the Device Tree otherwise.
+  //
+  Status = gBS->InstallProtocolInterface (
+                  &ImageHandle,
+                  &gEdkiiPlatformHasDeviceTreeGuid,
+                  EFI_NATIVE_INTERFACE,
+                  NULL
+                  );
+  if (EFI_ERROR (Status)) {
+    goto Failed;
+  }
+
+  return Status;
+
+Failed:
+  ASSERT_EFI_ERROR (Status);
+  CpuDeadLoop ();
+  //
+  // Keep compilers happy.
+  //
+  return Status;
+}