[PATCH v2 5/5] OvmfPkg/OvmfXen: Introduce DEBUG_ON_HYPERVISOR_CONSOLE build flag

["Anthony PERARD" <anthony.perard@citrix.com>]

Introduce DEBUG_ON_HYPERVISOR_CONSOLE build flag to enable logging
debug output to the Xen console.

This will work with both Xen HVM guest and Xen PVH guest whereas the
default PlatformDebugLibIoPort works only in HVM when QEMU is present.

Signed-off-by: Anthony PERARD <anthony.perard@citrix.com>
---
 OvmfPkg/OvmfXen.dsc | 13 +++++++++++++
 1 file changed, 13 insertions(+)

diff --git a/OvmfPkg/OvmfXen.dsc b/OvmfPkg/OvmfXen.dsc
index 4859faf1bff7..0a8fd26990a3 100644
--- a/OvmfPkg/OvmfXen.dsc
+++ b/OvmfPkg/OvmfXen.dsc
@@ -205,14 +205,22 @@ [LibraryClasses]
   Tcg2PhysicalPresenceLib|OvmfPkg/Library/Tcg2PhysicalPresenceLibNull/DxeTcg2PhysicalPresenceLib.inf
   TpmMeasurementLib|MdeModulePkg/Library/TpmMeasurementLibNull/TpmMeasurementLibNull.inf
   RealTimeClockLib|OvmfPkg/Library/XenRealTimeClockLib/XenRealTimeClockLib.inf
+!ifdef $(DEBUG_ON_HYPERVISOR_CONSOLE)
+  DebugLib|OvmfPkg/Library/PlatformDebugLibIoPort/PlatformRomDebugLibIoPortNocheck.inf
+!else
   DebugLib|OvmfPkg/Library/PlatformDebugLibIoPort/PlatformDebugLibIoPort.inf
+!endif
 
 [LibraryClasses.common]
   BaseCryptLib|CryptoPkg/Library/BaseCryptLib/BaseCryptLib.inf
 
 [LibraryClasses.common.SEC]
   QemuFwCfgLib|OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgSecLib.inf
+!ifdef $(DEBUG_ON_HYPERVISOR_CONSOLE)
+  DebugLib|OvmfPkg/Library/PlatformDebugLibIoPort/PlatformRomDebugLibIoPortNocheck.inf
+!else
   DebugLib|OvmfPkg/Library/PlatformDebugLibIoPort/PlatformRomDebugLibIoPort.inf
+!endif
   ReportStatusCodeLib|MdeModulePkg/Library/PeiReportStatusCodeLib/PeiReportStatusCodeLib.inf
   ExtractGuidedSectionLib|MdePkg/Library/BaseExtractGuidedSectionLib/BaseExtractGuidedSectionLib.inf
 !if $(SOURCE_DEBUG_ENABLE) == TRUE
@@ -405,6 +413,11 @@ [PcdsFixedAtBuild]
   #
 !include NetworkPkg/NetworkPcds.dsc.inc
 
+!ifdef $(DEBUG_ON_HYPERVISOR_CONSOLE)
+  ## Set Xen's debug IO port for PlatformDebugLibIoPort
+  gUefiOvmfPkgTokenSpaceGuid.PcdDebugIoPort|0xe9
+!endif
+
   # IRQs 5, 9, 10, 11 are level-triggered
   gUefiOvmfPkgTokenSpaceGuid.Pcd8259LegacyModeEdgeLevel|0x0E20
 
-- 
Anthony PERARD