[edk2][PATCH v2 1/2] MdeModulePkg: PcdAcpiExposedTableVersions default for Arm64 platforms

["Samer El-Haj-Mahmoud" <samer@elhajmahmoud.com>]

Set the default value of PcdAcpiExposedTableVersions for Aarch64
platforms to 0x20. Previously, the default was set to 0x3E for all
platforms. The new value removes ACPI 1.0b compatability, which forces
the use of XSDT 64-bit pointer, as required by Arm SBBR specification.
This also resolves an error reported by acpiview command, as seen on
the RPi (see https://github.com/pftf/RPi4/issues/25).

Cc: Dandan Bi <dandan.bi@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Cc: Jian J Wang <jian.j.wang@intel.com>
Cc: Hao A Wu <hao.a.wu@intel.com>
Cc: Leif Lindholm <leif@nuviainc.com>
Cc: Ard Biesheuvel <ard.biesheuvel@arm.com>

Signed-off-by: Samer El-Haj-Mahmoud <samer@elhajmahmoud.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Dandan Bi <dandan.bi@intel.com>
---
 MdeModulePkg/MdeModulePkg.dec | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/MdeModulePkg/MdeModulePkg.dec b/MdeModulePkg/MdeModulePkg.dec
index 497574cb0870..fac16f262cf8 100644
--- a/MdeModulePkg/MdeModulePkg.dec
+++ b/MdeModulePkg/MdeModulePkg.dec
@@ -1548,6 +1548,9 @@
   # @Prompt Console Output Row of Text Setup
   gEfiMdeModulePkgTokenSpaceGuid.PcdSetupConOutRow|25|UINT32|0x4000000e
 
+[PcdsFixedAtBuild.AARCH64, PcdsPatchableInModule.AARCH64]
+  gEfiMdeModulePkgTokenSpaceGuid.PcdAcpiExposedTableVersions|0x20|UINT32|0x0001004c
+
 [PcdsFixedAtBuild, PcdsPatchableInModule, PcdsDynamic, PcdsDynamicEx]
   ## UART clock frequency is for the baud rate configuration.
   # @Prompt Serial Port Clock Rate.
-- 
2.17.1