From 07c721fea7d7d7ee6c4e2637c993dff7d46bb5bd Mon Sep 17 00:00:00 2001
From: Min Xu <min.m.xu@intel.com>
Date: Wed, 22 Sep 2021 20:16:12 +0800
Subject: [PATCH] OvmfPkg/QemuFwCfgLib: Support Tdx in QemuFwCfgDxe

RFC: https://bugzilla.tianocore.org/show_bug.cgi?id=3429

In the previous QemuFwCfgDxe only SEV is supported. This commit
introduce TDX support in QemuFwCfgDxe.

Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Cc: Brijesh Singh <brijesh.singh@amd.com>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: James Bottomley <jejb@linux.ibm.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
Signed-off-by: Min Xu <min.m.xu@intel.com>
---
 OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgDxe.c      | 9 +++++----
 OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgDxeLib.inf | 1 +
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgDxe.c b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgDxe.c
index f5787cd24d..6a810928a0 100644
--- a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgDxe.c
+++ b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgDxe.c
@@ -19,6 +19,7 @@
 #include <Library/DebugLib.h>
 #include <Library/QemuFwCfgLib.h>
 #include <Library/UefiBootServicesTableLib.h>
+#include <Library/MemEncryptTdxLib.h>
 #include <Library/MemEncryptSevLib.h>
 
 #include "QemuFwCfgLibInternal.h"
@@ -85,7 +86,7 @@ QemuFwCfgInitialize (
     DEBUG ((DEBUG_INFO, "QemuFwCfg interface (DMA) is supported.\n"));
   }
 
-  if (mQemuFwCfgDmaSupported && MemEncryptSevIsEnabled ()) {
+  if (mQemuFwCfgDmaSupported && (MemEncryptSevIsEnabled () || (MemEncryptTdxIsEnabled ()))) {
     EFI_STATUS  Status;
 
     //
@@ -100,7 +101,7 @@ QemuFwCfgInitialize (
     if (EFI_ERROR (Status)) {
       DEBUG ((
         DEBUG_ERROR,
-        "QemuFwCfgSevDma %a:%a Failed to locate IOMMU protocol.\n",
+        "QemuFwCfgDma %a:%a Failed to locate IOMMU protocol.\n",
         gEfiCallerBaseName,
         __FUNCTION__
         ));
@@ -411,10 +412,10 @@ InternalQemuFwCfgDmaBytes (
   DataBuffer    = Buffer;
 
   //
-  // When SEV is enabled, map Buffer to DMA address before issuing the DMA
+  // When SEV or TDX is enabled, map Buffer to DMA address before issuing the DMA
   // request
   //
-  if (MemEncryptSevIsEnabled ()) {
+  if (MemEncryptSevIsEnabled () || MemEncryptTdxIsEnabled ()) {
     VOID                  *AccessBuffer;
     EFI_PHYSICAL_ADDRESS  DataBufferAddress;
 
diff --git a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgDxeLib.inf b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgDxeLib.inf
index 48899ff123..ce3eaa5ed8 100644
--- a/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgDxeLib.inf
+++ b/OvmfPkg/Library/QemuFwCfgLib/QemuFwCfgDxeLib.inf
@@ -43,6 +43,7 @@
   IoLib
   MemoryAllocationLib
   MemEncryptSevLib
+  MemEncryptTdxLib
 
 [Protocols]
   gEdkiiIoMmuProtocolGuid                         ## SOMETIMES_CONSUMES