From: Laszlo Ersek <lersek@redhat.com>
Date: Fri, 17 Mar 2017 12:44:41 +0000 (+0100)
Subject: Revert "ArmVirtPkg/FdtClientDxe: install DT configuration table at ReadyToBoot"
X-Git-Tag: edk2-stable201903~4316
X-Git-Url: https://git.proxmox.com/?p=mirror_edk2.git;a=commitdiff_plain;h=a00601c6de65d0d1b43bd91ba6c43238d9db2ed4

Revert "ArmVirtPkg/FdtClientDxe: install DT configuration table at ReadyToBoot"

This reverts commit 18f6d4df9ece8b91b86511bcdd1cf7da478c3627.

We realized that DXE drivers that are independent of AcpiPlatformDxe (that
is, independent of QEMU's ACPI generation), such as RamDiskDxe and
BootGraphicsResourceTableDxe, may produce and/or manipulate ACPI tables,
at driver dispatch or even at Ready To Boot.

This makes it unsafe for us to check for ACPI presence in the UEFI system
config table in a Ready To Boot callback, in order to decide about
exposing the DT.

Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Leif Lindholm <leif.lindholm@linaro.org>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
---

diff --git a/ArmVirtPkg/FdtClientDxe/FdtClientDxe.c b/ArmVirtPkg/FdtClientDxe/FdtClientDxe.c
index 4cf79f70cb..547a29fce6 100644
--- a/ArmVirtPkg/FdtClientDxe/FdtClientDxe.c
+++ b/ArmVirtPkg/FdtClientDxe/FdtClientDxe.c
@@ -20,7 +20,6 @@
 #include <Library/HobLib.h>
 #include <libfdt.h>
 
-#include <Guid/EventGroup.h>
 #include <Guid/Fdt.h>
 #include <Guid/FdtHob.h>
 
@@ -307,30 +306,6 @@ STATIC FDT_CLIENT_PROTOCOL mFdtClientProtocol = {
   GetOrInsertChosenNode,
 };
 
-STATIC
-VOID
-EFIAPI
-OnReadyToBoot (
-  EFI_EVENT       Event,
-  VOID            *Context
-  )
-{
-  EFI_STATUS      Status;
-
-  if (!FeaturePcdGet (PcdPureAcpiBoot)) {
-    //
-    // Only install the FDT as a configuration table if we want to leave it up
-    // to the OS to decide whether it prefers ACPI over DT.
-    //
-    Status = gBS->InstallConfigurationTable (&gFdtTableGuid, mDeviceTreeBase);
-    ASSERT_EFI_ERROR (Status);
-  }
-
-  gBS->CloseEvent (Event);
-}
-
-STATIC EFI_EVENT         mReadyToBootEvent;
-
 EFI_STATUS
 EFIAPI
 InitializeFdtClientDxe (
@@ -358,21 +333,15 @@ InitializeFdtClientDxe (
 
   DEBUG ((EFI_D_INFO, "%a: DTB @ 0x%p\n", __FUNCTION__, mDeviceTreeBase));
 
-  Status = gBS->InstallProtocolInterface (&ImageHandle, &gFdtClientProtocolGuid,
-                  EFI_NATIVE_INTERFACE, &mFdtClientProtocol);
-  if (EFI_ERROR (Status)) {
-    return Status;
+  if (!FeaturePcdGet (PcdPureAcpiBoot)) {
+    //
+    // Only install the FDT as a configuration table if we want to leave it up
+    // to the OS to decide whether it prefers ACPI over DT.
+    //
+    Status = gBS->InstallConfigurationTable (&gFdtTableGuid, DeviceTreeBase);
+    ASSERT_EFI_ERROR (Status);
   }
 
-  Status = gBS->CreateEventEx (
-                  EVT_NOTIFY_SIGNAL,
-                  TPL_CALLBACK,
-                  OnReadyToBoot,
-                  NULL,
-                  &gEfiEventReadyToBootGuid,
-                  &mReadyToBootEvent
-                  );
-  ASSERT_EFI_ERROR (Status);
-
-  return EFI_SUCCESS;
+  return gBS->InstallProtocolInterface (&ImageHandle, &gFdtClientProtocolGuid,
+                EFI_NATIVE_INTERFACE, &mFdtClientProtocol);
 }
diff --git a/ArmVirtPkg/FdtClientDxe/FdtClientDxe.inf b/ArmVirtPkg/FdtClientDxe/FdtClientDxe.inf
index 00017727c3..3a0cd37040 100644
--- a/ArmVirtPkg/FdtClientDxe/FdtClientDxe.inf
+++ b/ArmVirtPkg/FdtClientDxe/FdtClientDxe.inf
@@ -42,7 +42,6 @@
   gFdtClientProtocolGuid                  ## PRODUCES
 
 [Guids]
-  gEfiEventReadyToBootGuid
   gFdtHobGuid
   gFdtTableGuid