MdeModulePkg: SmmLockBoxPeiLib: work without EFI_PEI_SMM_COMMUNICATION_PPI

The RestoreLockBox() and RestoreAllLockBoxInPlace() functions handle the
case when EFI_PEI_SMM_COMMUNICATION_PPI.Communicate() returns
EFI_NOT_STARTED: they access the SMRAM directly, for restoring LockBox
data.

This occurs if a PEIM needs to restore LockBox data *before* the SMBASE is
relocated and the SMI handler is installed for all processors.

One such PEIM is UefiCpuPkg/Universal/Acpi/S3Resume2Pei. On the S3 resume
path, in function S3RestoreConfig2(), LockBox data are restored *before*
the SmmRestoreCpu() function of UefiCpuPkg/PiSmmCpuDxeSmm is called via
SmmS3ResumeState->SmmS3ResumeEntryPoint. (The latter SmmRestoreCpu()
function is responsible for the SMBASE relocation.)

If a platform knows that its PEIMs restore LockBox data *only* before
SMBASE relocation -- e.g., due to S3Resume2Pei being the platform's only
SmmLockBoxPeiLib client --, then the platform might not want to include
"UefiCpuPkg/PiSmmCommunication/PiSmmCommunicationPei.inf" at all (hence
not provide EFI_PEI_SMM_COMMUNICATION_PPI) -- because all of those
restores would be serviced by direct SMRAM access anyway.

Currently the absence of EFI_PEI_SMM_COMMUNICATION_PPI is not supported by
SmmLockBoxPeiLib, but it's not hard to implement. Handle it the same as
when EFI_PEI_SMM_COMMUNICATION_PPI.Communicate() returns EFI_NOT_STARTED:
restore LockBox data directly from SMRAM.

Suggested-by: Jiewen Yao <jiewen.yao@intel.com>
Cc: Jiewen Yao <jiewen.yao@intel.com>
Cc: Michael Kinney <michael.d.kinney@intel.com>
Cc: Jordan Justen <jordan.l.justen@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@18823 6f19259b-4bc3-4df7-8a09-765794883524

diff --git a/MdeModulePkg/Library/SmmLockBoxLib/SmmLockBoxPeiLib.c b/MdeModulePkg/Library/SmmLockBoxLib/SmmLockBoxPeiLib.c
index bd3204b195343cdf6c89262a64a0d871e8f6ad52..cea1fed682d4614711b27e6115db0154f3bbee8d 100644 (file)
--- a/MdeModulePkg/Library/SmmLockBoxLib/SmmLockBoxPeiLib.c
+++ b/MdeModulePkg/Library/SmmLockBoxLib/SmmLockBoxPeiLib.c
@@ -563,7 +563,10 @@ RestoreLockBox (
              (VOID **)&SmmCommunicationPpi\r
              );\r
   if (EFI_ERROR (Status)) {\r
-    return EFI_NOT_STARTED;\r
+    DEBUG ((EFI_D_INFO, "SmmLockBoxPeiLib LocatePpi - (%r)\n", Status));\r
+    Status = InternalRestoreLockBoxFromSmram (Guid, Buffer, Length);\r
+    DEBUG ((EFI_D_INFO, "SmmLockBoxPeiLib RestoreLockBox - Exit (%r)\n", Status));\r
+    return Status;\r
   }\r
 \r
   //\r
@@ -682,7 +685,10 @@ RestoreAllLockBoxInPlace (
              (VOID **)&SmmCommunicationPpi\r
              );\r
   if (EFI_ERROR (Status)) {\r
-    return EFI_NOT_STARTED;\r
+    DEBUG ((EFI_D_INFO, "SmmLockBoxPeiLib LocatePpi - (%r)\n", Status));\r
+    Status = InternalRestoreAllLockBoxInPlaceFromSmram ();\r
+    DEBUG ((EFI_D_INFO, "SmmLockBoxPeiLib RestoreAllLockBoxInPlace - Exit (%r)\n", Status));\r
+    return Status;\r
   }\r
 \r
   //\r