1 files changed, 57 insertions, 0 deletions
diff --git a/roms/edk2/MdeModulePkg/Include/Guid/PiSmmCommunicationRegionTable.h b/roms/edk2/MdeModulePkg/Include/Guid/PiSmmCommunicationRegionTable.h
new file mode 100644
index 000000000..595003bfb
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+++ b/roms/edk2/MdeModulePkg/Include/Guid/PiSmmCommunicationRegionTable.h
@@ -0,0 +1,57 @@
+/** @file
+
+Copyright (c) 2015 - 2018, Intel Corporation. All rights reserved.<BR>
+SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#ifndef _PI_SMM_COMMUNICATION_REGION_TABLE_H_
+#define _PI_SMM_COMMUNICATION_REGION_TABLE_H_
+
+#define EDKII_PI_SMM_COMMUNICATION_REGION_TABLE_GUID {\
+  0x4e28ca50, 0xd582, 0x44ac, {0xa1, 0x1f, 0xe3, 0xd5, 0x65, 0x26, 0xdb, 0x34} \
+}
+
+//
+// This table to declare the generic SMM communication buffer location.
+// If this table is present, it means the SMM communication buffer is restricted to
+// EfiReservedMemoryType, EfiACPIMemoryNVS, or EfiRuntimeServicesData.
+//
+// This table is installed to UEFI configuration table by generic driver
+// or platform driver, at early DXE phase.
+//
+// The EFI_MEMORY_DESCRIPTOR entry must contain at least one entry.
+// The entries must be normal memory region in EfiReservedMemoryType, EfiACPIMemoryNVS,
+// or EfiRuntimeServicesData.
+// If the Entry.Type is EfiConventionalMemory, it means this entry is free to use.
+// If the Entry.Type is other, it means this entry is occupied.
+//
+// Any non-SMM component may put communication data there, then use
+// UEFI defined SMM Communication ACPI Table, or PI defined EFI_SMM_COMMUNICATION_PROTOCOL
+// to communicate with SMI handler. The process is:
+// 1) Find an entry whose type is EfiConventional.
+// 2) Change type to be EfiReservedMemoryType before use.
+// 3) Use it.
+// 4) Restore type be EfiConventional.
+//    The step 2) must be performed as an atomic transaction, if there might be conflict during runtime.
+//    For example, on IA-32/x64 platforms, this can be done using the CMPXCHG CPU instruction.
+//    If there is guarantee on no conflict during boot time, these steps can be skipped.
+//    For example, DXE, UEFI driver and UEFI application runs in sequence.
+//
+// For example, FPDT driver can use this communication buffer to get SMM
+// performance data in SMM. Profile driver can use this communication buffer
+// to get SMM profile data in SMM.
+//
+typedef struct {
+  UINT32                Version;
+  UINT32                NumberOfEntries;
+  UINT32                DescriptorSize;
+  UINT32                Reserved;
+//EFI_MEMORY_DESCRIPTOR Entry[1];
+} EDKII_PI_SMM_COMMUNICATION_REGION_TABLE;
+
+#define EDKII_PI_SMM_COMMUNICATION_REGION_TABLE_VERSION  0x00000001
+
+extern EFI_GUID gEdkiiPiSmmCommunicationRegionTableGuid;
+
+#endif