SmmLockBox, 0170, 11 KB, SMM

SMM LockBox driver providing save/restore services within SMM for data that must survive S3 resume. Processes five LockBox commands via SMI handler: Save, Update, Restore, SetAttributes, and RestoreAllInPlace. Stored entries reside in SMRAM pages and are guarded by a lock mechanism preventing further saves after S3 preparation.

Key Functions: SmmLockBoxHandler (SMI dispatch for LockBox commands), SmmLockBoxSaveLockBox (allocate SMRAM pages + entry, copy data), SmmLockBoxUpdateLockBox (modify existing entry at offset), SmmLockBoxRestoreLockBox (copy data out of SMRAM), SmmLockBoxRestoreAllLockBoxInPlace (batch restore entries with RESTORE_IN_PLACE attribute).

Protocols/Dependencies: AMI SMM Communication Protocol, AMI SMM Buffer Validation Protocol, SMM SW Dispatch2 Protocol, SMM Configuration Table for LockBox context.

Platform: Intel Purley (Skylake-SP) / HR650X server, MdeModulePkg/Universal/LockBox/SmmLockBox