[RFC PATCH v1 21/30] ArmVirtPkg: Kvmtool: Use Null version of DebugLib in PrePi

["Sami Mujawar" <sami.mujawar@arm.com>]

The patch at "6c8a08bd8a680 ArmVirtPkg/PrePi: Ensure timely
 execution of library constructors" moved the processing of
library constructors before the MMU is initialised.

This resulted in the BaseDebugLibSerialPort library constructor
BaseDebugLibSerialPortConstructor () which initialises the serial
port, being invoked before the MMU is enabled.

However, the Realm Code requires the protection attribute of
the MMIO regions to be configured as unprotected (shared with
the host), which requires the MMU to be enabled. Otherwise,
accesses to the MMIO region result in a synchronous external
abort being reflected to the Realm by the RMM.

Therefore, link the Null version of DebugLib in PrePi stage.

Signed-off-by: Sami Mujawar <sami.mujawar@arm.com>
---
 ArmVirtPkg/ArmVirtKvmTool.dsc | 1 +
 1 file changed, 1 insertion(+)

diff --git a/ArmVirtPkg/ArmVirtKvmTool.dsc b/ArmVirtPkg/ArmVirtKvmTool.dsc
index 467e5c166e1bbad3acbae78f53c225f5bac525a9..1cfd9e7ed8a6d2b0b054e130a84c66c2fec54e57 100644
--- a/ArmVirtPkg/ArmVirtKvmTool.dsc
+++ b/ArmVirtPkg/ArmVirtKvmTool.dsc
@@ -248,6 +248,7 @@ [Components.common]
   #
   ArmVirtPkg/PrePi/ArmVirtPrePiUniCoreRelocatable.inf {
     <LibraryClasses>
+      DebugLib|MdePkg/Library/BaseDebugLibNull/BaseDebugLibNull.inf
       ExtractGuidedSectionLib|EmbeddedPkg/Library/PrePiExtractGuidedSectionLib/PrePiExtractGuidedSectionLib.inf
       LzmaDecompressLib|MdeModulePkg/Library/LzmaCustomDecompressLib/LzmaCustomDecompressLib.inf
       PrePiLib|EmbeddedPkg/Library/PrePiLib/PrePiLib.inf
-- 
'Guid(CE165669-3EF3-493F-B85D-6190EE5B9759)'