OvmfPkg/ResetVector: split TDX BSP workflow

Create a separate control flow for TDX BSP.

TdxPostBuildPageTables will now only be called when running in TDX
mode, so the TDX check in that function is not needed any more.

No functional change.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Message-Id: <20240301074402.98625-5-kraxel@redhat.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Oliver Steffen <osteffen@redhat.com>
Cc: Michael Roth <michael.roth@amd.com>
Cc: Erdem Aktas <erdemaktas@google.com>
Cc: Min Xu <min.m.xu@intel.com>
Cc: Ard Biesheuvel <ardb+tianocore@kernel.org>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
[lersek@redhat.com: turn the "Cc:" message headers from Gerd's on-list
 posting into "Cc:" tags in the commit message, in order to pacify
 "PatchCheck.py"]

2 files changed, 10 insertions, 9 deletions

diff --git a/OvmfPkg/ResetVector/Ia32/IntelTdx.asm b/OvmfPkg/ResetVector/Ia32/IntelTdx.asm
index 06794baef8..c6b86019df 100644
--- a/OvmfPkg/ResetVector/Ia32/IntelTdx.asm
+++ b/OvmfPkg/ResetVector/Ia32/IntelTdx.asm
@@ -197,11 +197,7 @@ NotTdx:
 ; Set byte[TDX_WORK_AREA_PGTBL_READY] to 1

 ;

 TdxPostBuildPageTables:

-    cmp     byte[WORK_AREA_GUEST_TYPE], VM_GUEST_TDX

-    jne     ExitTdxPostBuildPageTables

     mov     byte[TDX_WORK_AREA_PGTBL_READY], 1

-

-ExitTdxPostBuildPageTables:

     OneTimeCallRet TdxPostBuildPageTables

 

 ;

diff --git a/OvmfPkg/ResetVector/Ia32/PageTables64.asm b/OvmfPkg/ResetVector/Ia32/PageTables64.asm
index 14cc2c33aa..166e80293c 100644
--- a/OvmfPkg/ResetVector/Ia32/PageTables64.asm
+++ b/OvmfPkg/ResetVector/Ia32/PageTables64.asm
@@ -112,7 +112,7 @@ SetCr3ForPageTables64:
     ; is set.

     OneTimeCall   CheckTdxFeaturesBeforeBuildPagetables

     cmp       eax, TDX_BSP

-    je        ClearOvmfPageTables

+    je        TdxBspInit

     cmp       eax, TDX_AP

     je        SetCr3

 

@@ -124,16 +124,21 @@ SetCr3ForPageTables64:
     ; the page table build below.

     OneTimeCall   GetSevCBitMaskAbove31

 

-ClearOvmfPageTables:

     ClearOvmfPageTables

     CreatePageTables4Level edx

 

     ; Clear the C-bit from the GHCB page if the SEV-ES is enabled.

     OneTimeCall   SevClearPageEncMaskForGhcbPage

+    jmp SetCr3

 

-    ; TDX will do some PostBuildPages task, such as setting

-    ; byte[TDX_WORK_AREA_PGTBL_READY].

-    OneTimeCall   TdxPostBuildPageTables

+TdxBspInit:

+    ;

+    ; TDX BSP workflow

+    ;

+    ClearOvmfPageTables

+    CreatePageTables4Level 0

+    OneTimeCall TdxPostBuildPageTables

+    jmp SetCr3

 

 SetCr3:

     ;