OvmfPkg: Don't access A20 gate register on Cloud Hypervisor

Since Cloud Hypervisor doesn't emulate an A20 gate register on I/O port
0x92, it's better to avoid accessing it when the platform is identified
as Cloud Hypervisor.

Signed-off-by: Sebastien Boeuf <sebastien.boeuf@intel.com>
Acked-by: Jiewen Yao <jiewen.yao@intel.com>

diff --git a/OvmfPkg/Library/PlatformInitLib/Platform.c b/OvmfPkg/Library/PlatformInitLib/Platform.c
index ee802fd684e150c504de01bbcfe10baab2787d97..c3d34e43af5ab66121190ec6387b7b0470d4800d 100644 (file)
--- a/OvmfPkg/Library/PlatformInitLib/Platform.c
+++ b/OvmfPkg/Library/PlatformInitLib/Platform.c
@@ -314,7 +314,9 @@ PlatformMiscInitialization (
   //\r
   // Disable A20 Mask\r
   //\r
-  IoOr8 (0x92, BIT1);\r
+  if (PlatformInfoHob->HostBridgeDevId != CLOUDHV_DEVICE_ID) {\r
+    IoOr8 (0x92, BIT1);\r
+  }\r
 \r
   //\r
   // Build the CPU HOB with guest RAM size dependent address width and 16-bits\r