diff --git a/ArmPkg/Drivers/ArmGic/ArmGicCommonDxe.c b/ArmPkg/Drivers/ArmGic/ArmGicCommonDxe.c
index d560c42fc9..8461fb7927 100644
--- a/ArmPkg/Drivers/ArmGic/ArmGicCommonDxe.c
+++ b/ArmPkg/Drivers/ArmGic/ArmGicCommonDxe.c
@@ -1,6 +1,6 @@
 /*++
 
-Copyright (c) 2013-2017, ARM Ltd. All rights reserved.<BR>
+Copyright (c) 2013-2023, Arm Ltd. All rights reserved.<BR>
 
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
@@ -61,7 +61,7 @@ GicGetDistributorIcfgBaseAndBit (
 
   RegIndex    = Source / ARM_GIC_ICDICFR_F_STRIDE; // NOTE: truncation is significant
   Field       = Source % ARM_GIC_ICDICFR_F_STRIDE;
-  *RegAddress = PcdGet64 (PcdGicDistributorBase)
+  *RegAddress = (UINTN)PcdGet64 (PcdGicDistributorBase)
                 + ARM_GIC_ICDICFR
                 + (ARM_GIC_ICDICFR_BYTES * RegIndex);
   *Config1Bit = ((Field * ARM_GIC_ICDICFR_F_WIDTH)
diff --git a/ArmPkg/Drivers/ArmGic/ArmGicLib.c b/ArmPkg/Drivers/ArmGic/ArmGicLib.c
index dd3670c7cc..e26035a902 100644
--- a/ArmPkg/Drivers/ArmGic/ArmGicLib.c
+++ b/ArmPkg/Drivers/ArmGic/ArmGicLib.c
@@ -1,6 +1,6 @@
 /** @file
 *
-*  Copyright (c) 2011-2021, Arm Limited. All rights reserved.
+*  Copyright (c) 2011-2023, Arm Limited. All rights reserved.
 *
 *  SPDX-License-Identifier: BSD-2-Clause-Patent
 *
@@ -117,7 +117,7 @@ ArmGicGetInterfaceIdentification (
 UINTN
 EFIAPI
 ArmGicGetMaxNumInterrupts (
-  IN  INTN  GicDistributorBase
+  IN  UINTN  GicDistributorBase
   )
 {
   UINTN  ItLines;
@@ -133,10 +133,10 @@ ArmGicGetMaxNumInterrupts (
 VOID
 EFIAPI
 ArmGicSendSgiTo (
-  IN  INTN  GicDistributorBase,
-  IN  INTN  TargetListFilter,
-  IN  INTN  CPUTargetList,
-  IN  INTN  SgiId
+  IN  UINTN  GicDistributorBase,
+  IN  INTN   TargetListFilter,
+  IN  INTN   CPUTargetList,
+  IN  INTN   SgiId
   )
 {
   MmioWrite32 (
@@ -390,7 +390,7 @@ ArmGicIsInterruptEnabled (
 VOID
 EFIAPI
 ArmGicDisableDistributor (
-  IN  INTN  GicDistributorBase
+  IN  UINTN  GicDistributorBase
   )
 {
   // Disable Gic Distributor
diff --git a/ArmPkg/Drivers/ArmGic/ArmGicNonSecLib.c b/ArmPkg/Drivers/ArmGic/ArmGicNonSecLib.c
index aa4f0e2123..38bbf2e9f8 100644
--- a/ArmPkg/Drivers/ArmGic/ArmGicNonSecLib.c
+++ b/ArmPkg/Drivers/ArmGic/ArmGicNonSecLib.c
@@ -1,6 +1,6 @@
 /** @file
 *
-*  Copyright (c) 2011-2015, ARM Limited. All rights reserved.
+*  Copyright (c) 2011-2023, Arm Limited. All rights reserved.
 *
 *  SPDX-License-Identifier: BSD-2-Clause-Patent
 *
@@ -13,7 +13,7 @@
 VOID
 EFIAPI
 ArmGicEnableDistributor (
-  IN  INTN  GicDistributorBase
+  IN  UINTN  GicDistributorBase
   )
 {
   ARM_GIC_ARCH_REVISION  Revision;
diff --git a/ArmPkg/Drivers/ArmGic/GicV2/ArmGicV2Dxe.c b/ArmPkg/Drivers/ArmGic/GicV2/ArmGicV2Dxe.c
index 779818ee89..a93f68495a 100644
--- a/ArmPkg/Drivers/ArmGic/GicV2/ArmGicV2Dxe.c
+++ b/ArmPkg/Drivers/ArmGic/GicV2/ArmGicV2Dxe.c
@@ -2,7 +2,7 @@
 
 Copyright (c) 2009, Hewlett-Packard Company. All rights reserved.<BR>
 Portions copyright (c) 2010, Apple Inc. All rights reserved.<BR>
-Portions copyright (c) 2011-2017, ARM Ltd. All rights reserved.<BR>
+Portions copyright (c) 2011-2023, Arm Ltd. All rights reserved.<BR>
 
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
@@ -400,8 +400,10 @@ GicV2DxeInitialize (
   // the system.
   ASSERT_PROTOCOL_ALREADY_INSTALLED (NULL, &gHardwareInterruptProtocolGuid);
 
+  ASSERT (PcdGet64 (PcdGicDistributorBase) <= MAX_UINTN);
+
   mGicInterruptInterfaceBase = PcdGet64 (PcdGicInterruptInterfaceBase);
-  mGicDistributorBase        = PcdGet64 (PcdGicDistributorBase);
+  mGicDistributorBase        = (UINTN)PcdGet64 (PcdGicDistributorBase);
   mGicNumInterrupts          = ArmGicGetMaxNumInterrupts (mGicDistributorBase);
 
   for (Index = 0; Index < mGicNumInterrupts; Index++) {
diff --git a/ArmPkg/Drivers/ArmGic/GicV3/ArmGicV3Dxe.c b/ArmPkg/Drivers/ArmGic/GicV3/ArmGicV3Dxe.c
index b1f0cd48c7..719701a67e 100644
--- a/ArmPkg/Drivers/ArmGic/GicV3/ArmGicV3Dxe.c
+++ b/ArmPkg/Drivers/ArmGic/GicV3/ArmGicV3Dxe.c
@@ -1,6 +1,6 @@
 /** @file
 *
-*  Copyright (c) 2011-2018, ARM Limited. All rights reserved.
+*  Copyright (c) 2011-2023, Arm Limited. All rights reserved.
 *
 *  SPDX-License-Identifier: BSD-2-Clause-Patent
 *
@@ -381,7 +381,7 @@ GicV3DxeInitialize (
   // the system.
   ASSERT_PROTOCOL_ALREADY_INSTALLED (NULL, &gHardwareInterruptProtocolGuid);
 
-  mGicDistributorBase    = PcdGet64 (PcdGicDistributorBase);
+  mGicDistributorBase    = (UINTN)PcdGet64 (PcdGicDistributorBase);
   mGicRedistributorsBase = PcdGet64 (PcdGicRedistributorsBase);
   mGicNumInterrupts      = ArmGicGetMaxNumInterrupts (mGicDistributorBase);
 
diff --git a/ArmPkg/Include/Library/ArmGicLib.h b/ArmPkg/Include/Library/ArmGicLib.h
index 4ab6709675..928d1541d9 100644
--- a/ArmPkg/Include/Library/ArmGicLib.h
+++ b/ArmPkg/Include/Library/ArmGicLib.h
@@ -1,6 +1,6 @@
 /** @file
 *
-*  Copyright (c) 2011-2021, Arm Limited. All rights reserved.<BR>
+*  Copyright (c) 2011-2023, Arm Limited. All rights reserved.<BR>
 *
 *  SPDX-License-Identifier: BSD-2-Clause-Patent
 *
@@ -121,7 +121,7 @@ VOID
 EFIAPI
 ArmGicSetupNonSecure (
   IN  UINTN  MpId,
-  IN  INTN   GicDistributorBase,
+  IN  UINTN  GicDistributorBase,
   IN  INTN   GicInterruptInterfaceBase
   );
 
@@ -148,28 +148,28 @@ ArmGicDisableInterruptInterface (
 VOID
 EFIAPI
 ArmGicEnableDistributor (
-  IN  INTN  GicDistributorBase
+  IN  UINTN  GicDistributorBase
   );
 
 VOID
 EFIAPI
 ArmGicDisableDistributor (
-  IN  INTN  GicDistributorBase
+  IN  UINTN  GicDistributorBase
   );
 
 UINTN
 EFIAPI
 ArmGicGetMaxNumInterrupts (
-  IN  INTN  GicDistributorBase
+  IN  UINTN  GicDistributorBase
   );
 
 VOID
 EFIAPI
 ArmGicSendSgiTo (
-  IN  INTN  GicDistributorBase,
-  IN  INTN  TargetListFilter,
-  IN  INTN  CPUTargetList,
-  IN  INTN  SgiId
+  IN  UINTN  GicDistributorBase,
+  IN  INTN   TargetListFilter,
+  IN  INTN   CPUTargetList,
+  IN  INTN   SgiId
   );
 
 /*
@@ -251,7 +251,7 @@ VOID
 EFIAPI
 ArmGicV2SetupNonSecure (
   IN  UINTN  MpId,
-  IN  INTN   GicDistributorBase,
+  IN  UINTN  GicDistributorBase,
   IN  INTN   GicInterruptInterfaceBase
   );