[PATCH 4/4] UefiPayloadPkg: Add a macro to enable or diable the serial driver.

["Zhiguang Liu" <zhiguang.liu@intel.com>]

This patch doesn't change the default behavior.

Cc: Guo Dong <guo.dong@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Maurice Ma <maurice.ma@intel.com>
Cc: Benjamin You <benjamin.you@intel.com>

Signed-off-by: Zhiguang Liu <zhiguang.liu@intel.com>
---
 UefiPayloadPkg/UefiPayloadPkg.dsc | 4 ++++
 UefiPayloadPkg/UefiPayloadPkg.fdf | 2 ++
 2 files changed, 6 insertions(+)

diff --git a/UefiPayloadPkg/UefiPayloadPkg.dsc b/UefiPayloadPkg/UefiPayloadPkg.dsc
index 002d2a8fa7..b4a30be381 100644
--- a/UefiPayloadPkg/UefiPayloadPkg.dsc
+++ b/UefiPayloadPkg/UefiPayloadPkg.dsc
@@ -98,6 +98,8 @@
   DEFINE RTC_INDEX_REGISTER = 0x70
   DEFINE RTC_TARGET_REGISTER = 0x71
 
+  DEFINE SERIAL_DRIVER_ENABLE = TRUE
+
 [BuildOptions]
   *_*_*_CC_FLAGS                 = -D DISABLE_NEW_DEPRECATED_INTERFACES
   GCC:*_UNIXGCC_*_CC_FLAGS       = -DMDEPKG_NDEBUG
@@ -536,7 +538,9 @@
   #
   # ISA Support
   #
+!if $(SERIAL_DRIVER_ENABLE) == TRUE
   MdeModulePkg/Universal/SerialDxe/SerialDxe.inf
+!endif
 !if $(PS2_KEYBOARD_ENABLE) == TRUE
   OvmfPkg/SioBusDxe/SioBusDxe.inf
   MdeModulePkg/Bus/Isa/Ps2KeyboardDxe/Ps2KeyboardDxe.inf
diff --git a/UefiPayloadPkg/UefiPayloadPkg.fdf b/UefiPayloadPkg/UefiPayloadPkg.fdf
index 041fed842c..b2cfb6b405 100644
--- a/UefiPayloadPkg/UefiPayloadPkg.fdf
+++ b/UefiPayloadPkg/UefiPayloadPkg.fdf
@@ -136,7 +136,9 @@ INF MdeModulePkg/Bus/Pci/PciHostBridgeDxe/PciHostBridgeDxe.inf
 #
 # ISA Support
 #
+!if $(SERIAL_DRIVER_ENABLE) == TRUE
 INF MdeModulePkg/Universal/SerialDxe/SerialDxe.inf
+!endif
 !if $(PS2_KEYBOARD_ENABLE) == TRUE
 INF OvmfPkg/SioBusDxe/SioBusDxe.inf
 INF MdeModulePkg/Bus/Isa/Ps2KeyboardDxe/Ps2KeyboardDxe.inf
-- 
2.32.0.windows.2