diff options
Diffstat (limited to 'StandaloneMmPkg/Drivers/MmCommunicationNotifyDxe/MmCommunicationNotifyDxe.c')
| -rw-r--r-- | StandaloneMmPkg/Drivers/MmCommunicationNotifyDxe/MmCommunicationNotifyDxe.c | 265 |
1 files changed, 265 insertions, 0 deletions
diff --git a/StandaloneMmPkg/Drivers/MmCommunicationNotifyDxe/MmCommunicationNotifyDxe.c b/StandaloneMmPkg/Drivers/MmCommunicationNotifyDxe/MmCommunicationNotifyDxe.c new file mode 100644 index 0000000..8e49b53 --- /dev/null +++ b/StandaloneMmPkg/Drivers/MmCommunicationNotifyDxe/MmCommunicationNotifyDxe.c @@ -0,0 +1,265 @@ +/** @file
+ MmCommunicationNotifyDxe driver creates the notifications of
+ some protocols and event.
+
+ Copyright (c) 2025, Intel Corporation. All rights reserved.<BR>
+ SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include "MmCommunicationNotifyDxe.h"
+
+//
+// PI 1.7 MM Communication Protocol 2 instance
+//
+EFI_MM_COMMUNICATION2_PROTOCOL *mMmCommunication2;
+MM_COMM_BUFFER mMmCommonBuffer;
+EFI_SMM_ACCESS2_PROTOCOL *mSmmAccess;
+BOOLEAN mSmmLocked = FALSE;
+BOOLEAN mEndOfDxe = FALSE;
+
+//
+// Table of Protocol notification and GUIDed Event notifications that the Standalone Mm requires
+//
+MM_EVENT_NOTIFICATION mMmEvents[] = {
+ //
+ // Declare protocol notification on DxeMmReadyToLock protocols. When this notification is established,
+ // the associated event is immediately signalled, so the notification function will be executed and the
+ // DXE Mm Ready To Lock Protocol will be found if it is already in the handle database.
+ //
+ { ProtocolNotify, TRUE, &gEfiDxeMmReadyToLockProtocolGuid, MmReadyToLockEventNotify, &gEfiDxeMmReadyToLockProtocolGuid, NULL },
+ //
+ // Declare event notification on Ready To Boot Event Group. This is an extra event notification that is
+ // used to make sure SMRAM is locked before any boot options are processed.
+ //
+ { EventNotify, TRUE, &gEfiEventReadyToBootGuid, MmReadyToLockEventNotify, &gEfiEventReadyToBootGuid, NULL },
+ //
+ // Declare event notification on Ready To Boot Event Group. This is used to inform the MM Core
+ // to notify MM driver that system enter ready to boot.
+ //
+ { EventNotify, FALSE, &gEfiEventReadyToBootGuid, MmGuidedEventNotify, &gEfiEventReadyToBootGuid, NULL },
+ //
+ // Declare event notification on EndOfDxe event. When this notification is established,
+ // the associated event is immediately signalled, so the notification function will be executed and the
+ // End Of Dxe Protocol will be found if it is already in the handle database.
+ //
+ { EventNotify, TRUE, &gEfiEndOfDxeEventGroupGuid, MmGuidedEventNotify, &gEfiEndOfDxeEventGroupGuid, NULL },
+ //
+ // Declare event notification on EndOfDxe event. This is used to set EndOfDxe event signaled flag.
+ //
+ { EventNotify, TRUE, &gEfiEndOfDxeEventGroupGuid, MmEndOfDxeEventNotify, &gEfiEndOfDxeEventGroupGuid, NULL },
+ //
+ // Declare event notification on Exit Boot Services Event Group. This is used to inform the MM Core
+ // to notify MM driver that system enter exit boot services.
+ //
+ { EventNotify, FALSE, &gEfiEventExitBootServicesGuid, MmGuidedEventNotify, &gEfiEventExitBootServicesGuid, NULL },
+ //
+ // Terminate the table of event notifications
+ //
+ { EndNotify, FALSE, NULL, NULL, NULL, NULL }
+};
+
+/**
+ Event notification that is fired when GUIDed Event Group is signaled.
+
+ @param Event The Event that is being processed, not used.
+ @param Context Event Context, not used.
+
+**/
+VOID
+EFIAPI
+MmGuidedEventNotify (
+ IN EFI_EVENT Event,
+ IN VOID *Context
+ )
+{
+ UINTN Size;
+ EFI_MM_COMMUNICATE_HEADER *CommunicateHeader;
+
+ CommunicateHeader = (EFI_MM_COMMUNICATE_HEADER *)(UINTN)mMmCommonBuffer.PhysicalStart;
+
+ //
+ // Use Guid to initialize EFI_MM_COMMUNICATE_HEADER structure
+ //
+ CopyGuid (&CommunicateHeader->HeaderGuid, (EFI_GUID *)Context);
+ CommunicateHeader->MessageLength = 1;
+ CommunicateHeader->Data[0] = 0;
+
+ //
+ // Generate the Software SMI and return the result
+ //
+ Size = sizeof (EFI_MM_COMMUNICATE_HEADER);
+ mMmCommunication2->Communicate (mMmCommunication2, CommunicateHeader, CommunicateHeader, &Size);
+}
+
+/**
+ Event notification that is fired every time a DxeSmmReadyToLock protocol is added
+ or if gEfiEventReadyToBootGuid is signaled.
+
+ @param Event The Event that is being processed, not used.
+ @param Context Event Context, not used.
+
+**/
+VOID
+EFIAPI
+MmReadyToLockEventNotify (
+ IN EFI_EVENT Event,
+ IN VOID *Context
+ )
+{
+ EFI_STATUS Status;
+ VOID *Interface;
+ UINTN Index;
+
+ //
+ // See if we are already locked
+ //
+ if (mSmmLocked) {
+ return;
+ }
+
+ //
+ // Make sure this notification is for this handler
+ //
+ if (CompareGuid ((EFI_GUID *)Context, &gEfiDxeMmReadyToLockProtocolGuid)) {
+ Status = gBS->LocateProtocol (&gEfiDxeMmReadyToLockProtocolGuid, NULL, &Interface);
+ if (EFI_ERROR (Status)) {
+ return;
+ }
+ } else {
+ //
+ // If MM is not locked yet and we got here from gEfiEventReadyToBootGuid being
+ // signaled, then gEfiDxeMmReadyToLockProtocolGuid was not installed as expected.
+ // Print a warning on debug builds.
+ //
+ DEBUG ((DEBUG_WARN, "DXE Mm Ready To Lock Protocol not installed before Ready To Boot signal\n"));
+ }
+
+ if (!mEndOfDxe) {
+ DEBUG ((DEBUG_ERROR, "EndOfDxe Event must be signaled before DxeSmmReadyToLock Protocol installation!\n"));
+ REPORT_STATUS_CODE (
+ EFI_ERROR_CODE | EFI_ERROR_UNRECOVERED,
+ (EFI_SOFTWARE_SMM_DRIVER | EFI_SW_EC_ILLEGAL_SOFTWARE_STATE)
+ );
+ ASSERT (FALSE);
+ }
+
+ //
+ // Lock the SMRAM (Note: Locking SMRAM may not be supported on all platforms)
+ //
+ mSmmAccess->Lock (mSmmAccess);
+
+ //
+ // Close protocol and event notification events that do not apply after the
+ // DXE MM Ready To Lock Protocol has been installed or the Ready To Boot
+ // event has been signalled.
+ //
+ for (Index = 0; mMmEvents[Index].NotifyFunction != NULL; Index++) {
+ if (mMmEvents[Index].CloseOnLock) {
+ gBS->CloseEvent (mMmEvents[Index].Event);
+ }
+ }
+
+ //
+ // Inform MM Core that the DxeSmmReadyToLock protocol was installed
+ //
+ MmGuidedEventNotify (Event, (VOID *)&gEfiDxeMmReadyToLockProtocolGuid);
+
+ //
+ // Print debug message that the SMRAM window is now locked.
+ //
+ DEBUG ((DEBUG_INFO, "MmCommunicationNotifyDxe locked SMRAM window\n"));
+
+ //
+ // Set flag so this operation will not be performed again
+ //
+ mSmmLocked = TRUE;
+}
+
+/**
+ Event notification that is fired when EndOfDxe Event Group is signaled.
+
+ @param Event The Event that is being processed, not used.
+ @param Context Event Context, not used.
+
+**/
+VOID
+EFIAPI
+MmEndOfDxeEventNotify (
+ IN EFI_EVENT Event,
+ IN VOID *Context
+ )
+{
+ mEndOfDxe = TRUE;
+}
+
+/**
+ The Entry Point for MmCommunicateNotifyDxe driver.
+
+ @param ImageHandle The firmware allocated handle for the EFI image.
+ @param SystemTable A pointer to the EFI System Table.
+
+ @retval EFI_SUCCESS The entry point is executed successfully.
+ @retval Other Some error occurred when executing this entry point.
+
+**/
+EFI_STATUS
+EFIAPI
+MmCommunicationNotifyEntryPoint (
+ IN EFI_HANDLE ImageHandle,
+ IN EFI_SYSTEM_TABLE *SystemTable
+ )
+{
+ EFI_STATUS Status;
+ EFI_HOB_GUID_TYPE *GuidHob;
+ MM_COMM_BUFFER *MmCommonBuffer;
+ UINTN Index;
+ VOID *Registration;
+
+ //
+ // Locate gMmCommBufferHobGuid and cache the content
+ //
+ GuidHob = GetFirstGuidHob (&gMmCommBufferHobGuid);
+ ASSERT (GuidHob != NULL);
+ MmCommonBuffer = GET_GUID_HOB_DATA (GuidHob);
+ CopyMem (&mMmCommonBuffer, MmCommonBuffer, sizeof (MM_COMM_BUFFER));
+
+ //
+ // Get SMM Access Protocol
+ //
+ Status = gBS->LocateProtocol (&gEfiSmmAccess2ProtocolGuid, NULL, (VOID **)&mSmmAccess);
+ ASSERT_EFI_ERROR (Status);
+
+ //
+ // Get MM Communication Protocol 2 instance
+ //
+ Status = gBS->LocateProtocol (&gEfiMmCommunication2ProtocolGuid, NULL, (VOID **)&mMmCommunication2);
+ ASSERT_EFI_ERROR (Status);
+
+ //
+ // Create the set of protocol and event notifications that the Standalone Mm requires
+ //
+ for (Index = 0; mMmEvents[Index].NotificationType != EndNotify; Index++) {
+ if (mMmEvents[Index].NotificationType == ProtocolNotify) {
+ mMmEvents[Index].Event = EfiCreateProtocolNotifyEvent (
+ mMmEvents[Index].Guid,
+ TPL_CALLBACK,
+ mMmEvents[Index].NotifyFunction,
+ mMmEvents[Index].NotifyContext,
+ &Registration
+ );
+ } else {
+ Status = gBS->CreateEventEx (
+ EVT_NOTIFY_SIGNAL,
+ TPL_CALLBACK,
+ mMmEvents[Index].NotifyFunction,
+ mMmEvents[Index].NotifyContext,
+ mMmEvents[Index].Guid,
+ &mMmEvents[Index].Event
+ );
+ ASSERT_EFI_ERROR (Status);
+ }
+ }
+
+ return EFI_SUCCESS;
+}
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