From: Ceping Sun <cepingx.sun@intel.com>
Date: Mon, 6 May 2024 22:33:57 +0000 (+0800)
Subject: OvmfPkg/QemuFwCfgS3Lib: Disable S3 detection in TDVF
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=e5715711a41b3a323b1605e41e5875d377e7c9c2;p=people%2Faperard%2Fovmf.git

OvmfPkg/QemuFwCfgS3Lib: Disable S3 detection in TDVF

Refer to the section 2.1 of tdx-virtual-firmware-design-guide spec,
APCI S3 is not supported in TDVF.

Therefore, TDVF should not read the S3 status via fw_cfg and always
set it as unsupported.

spec: https://cdrdv2.intel.com/v1/dl/getContent/733585

Cc: Erdem Aktas <erdemaktas@google.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Min Xu <min.m.xu@intel.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Signed-off-by: Ceping Sun <cepingx.sun@intel.com>
---

diff --git a/OvmfPkg/Library/QemuFwCfgS3Lib/QemuFwCfgS3PeiDxe.c b/OvmfPkg/Library/QemuFwCfgS3Lib/QemuFwCfgS3PeiDxe.c
index 270f050336..e0c21461ce 100644
--- a/OvmfPkg/Library/QemuFwCfgS3Lib/QemuFwCfgS3PeiDxe.c
+++ b/OvmfPkg/Library/QemuFwCfgS3Lib/QemuFwCfgS3PeiDxe.c
@@ -7,6 +7,7 @@
   SPDX-License-Identifier: BSD-2-Clause-Patent
 **/
 
+#include <Library/BaseLib.h>
 #include <Library/QemuFwCfgLib.h>
 #include <Library/QemuFwCfgS3Lib.h>
 
@@ -32,6 +33,10 @@ QemuFwCfgS3Enabled (
   UINTN                 FwCfgSize;
   UINT8                 SystemStates[6];
 
+  if (TdIsEnabled ()) {
+    return FALSE;
+  }
+
   Status = QemuFwCfgFindFile ("etc/system-states", &FwCfgItem, &FwCfgSize);
   if ((Status != RETURN_SUCCESS) || (FwCfgSize != sizeof SystemStates)) {
     return FALSE;