[PATCH v2 6/8] OvmfPkg/QemuFlashFvbServicesRuntimeDxe: don't set flash PCDs if SMM or no-emu

[Laszlo Ersek <lersek@redhat.com>]

... only check them. When OVMF is built with

  -D SMM_REQUIRE

or with

  -D MEM_VARSTORE_EMU_ENABLE=FALSE

then the PCDs are set during the PEI phase, as part of
FaultTolerantWritePei's startup (in FlashNvStorageAddressLib's
constructor).

Cc: Anthony Perard <anthony.perard@citrix.com>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Julien Grall <julien.grall@linaro.org>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
---
 OvmfPkg/QemuFlashFvbServicesRuntimeDxe/FwBlockService.c | 58 ++++++++++++++------
 1 file changed, 40 insertions(+), 18 deletions(-)

diff --git a/OvmfPkg/QemuFlashFvbServicesRuntimeDxe/FwBlockService.c b/OvmfPkg/QemuFlashFvbServicesRuntimeDxe/FwBlockService.c
index 558b395dff4a..5d5a7580454a 100644
--- a/OvmfPkg/QemuFlashFvbServicesRuntimeDxe/FwBlockService.c
+++ b/OvmfPkg/QemuFlashFvbServicesRuntimeDxe/FwBlockService.c
@@ -1093,24 +1093,46 @@ FvbInitialize (
 
   MarkMemoryRangeForRuntimeAccess (BaseAddress, Length);
 
-  //
-  // Set several PCD values to point to flash
-  //
-  PcdStatus = PcdSet64S (
-    PcdFlashNvStorageVariableBase64,
-    (UINTN) PcdGet32 (PcdOvmfFlashNvStorageVariableBase)
-    );
-  ASSERT_RETURN_ERROR (PcdStatus);
-  PcdStatus = PcdSet32S (
-    PcdFlashNvStorageFtwWorkingBase,
-    PcdGet32 (PcdOvmfFlashNvStorageFtwWorkingBase)
-    );
-  ASSERT_RETURN_ERROR (PcdStatus);
-  PcdStatus = PcdSet32S (
-    PcdFlashNvStorageFtwSpareBase,
-    PcdGet32 (PcdOvmfFlashNvStorageFtwSpareBase)
-    );
-  ASSERT_RETURN_ERROR (PcdStatus);
+  if (!FeaturePcdGet (PcdSmmSmramRequire) &&
+      FeaturePcdGet (PcdMemVarstoreEmuEnable)) {
+    //
+    // This build is suitable for both flash and in-memory emulated variables,
+    // and we happen to have found flash. Set several PCD values to point to
+    // flash.
+    //
+    PcdStatus = PcdSet64S (
+                  PcdFlashNvStorageVariableBase64,
+                  PcdGet32 (PcdOvmfFlashNvStorageVariableBase)
+                  );
+    ASSERT_RETURN_ERROR (PcdStatus);
+    PcdStatus = PcdSet32S (
+                  PcdFlashNvStorageFtwWorkingBase,
+                  PcdGet32 (PcdOvmfFlashNvStorageFtwWorkingBase)
+                  );
+    ASSERT_RETURN_ERROR (PcdStatus);
+    PcdStatus = PcdSet32S (
+                  PcdFlashNvStorageFtwSpareBase,
+                  PcdGet32 (PcdOvmfFlashNvStorageFtwSpareBase)
+                  );
+    ASSERT_RETURN_ERROR (PcdStatus);
+  } else {
+    //
+    // This build is suitable for flash variables only. Double-check several
+    // PCDs that point to the flash.
+    //
+    ASSERT (
+      (PcdGet64 (PcdFlashNvStorageVariableBase64) ==
+       PcdGet32 (PcdOvmfFlashNvStorageVariableBase))
+      );
+    ASSERT (
+      (PcdGet32 (PcdFlashNvStorageFtwWorkingBase) ==
+       PcdGet32 (PcdOvmfFlashNvStorageFtwWorkingBase))
+      );
+    ASSERT (
+      (PcdGet32 (PcdFlashNvStorageFtwSpareBase) ==
+       PcdGet32 (PcdOvmfFlashNvStorageFtwSpareBase))
+      );
+  }
 
   FwhInstance = (EFI_FW_VOL_INSTANCE *)
     (
-- 
2.14.1.3.gb7cf6e02401b