diff options
| author |   Angelos Mouzakitis <a.mouzakitis@virtualopensystems.com> | 2023-10-10 14:33:42 +0000 |
|---|---|---|
| committer | Angelos Mouzakitis <a.mouzakitis@virtualopensystems.com> | 2023-10-10 14:33:42 +0000 |
| commit | af1a266670d040d2f4083ff309d732d648afba2a (patch) | |
| tree | 2fc46203448ddcc6f81546d379abfaeb323575e9 /roms/edk2/EmbeddedPkg/EmbeddedMonotonicCounter/EmbeddedMonotonicCounter.c | |
| parent | e02cda008591317b1625707ff8e115a4841aa889 (diff) | |
Change-Id: Iaf8d18082d3991dec7c0ebbea540f092188eb4ec
Diffstat (limited to 'roms/edk2/EmbeddedPkg/EmbeddedMonotonicCounter/EmbeddedMonotonicCounter.c')
| -rw-r--r-- | roms/edk2/EmbeddedPkg/EmbeddedMonotonicCounter/EmbeddedMonotonicCounter.c | 76 |
1 files changed, 76 insertions, 0 deletions
diff --git a/roms/edk2/EmbeddedPkg/EmbeddedMonotonicCounter/EmbeddedMonotonicCounter.c b/roms/edk2/EmbeddedPkg/EmbeddedMonotonicCounter/EmbeddedMonotonicCounter.c new file mode 100644 index 000000000..089b1f694 --- /dev/null +++ b/roms/edk2/EmbeddedPkg/EmbeddedMonotonicCounter/EmbeddedMonotonicCounter.c @@ -0,0 +1,76 @@ +/** @file
+
+ Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
+
+ SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <Uefi.h>
+
+#include <Library/BaseLib.h>
+#include <Library/DebugLib.h>
+#include <Library/UefiBootServicesTableLib.h>
+#include <Library/UefiRuntimeServicesTableLib.h>
+
+#include <Protocol/MonotonicCounter.h>
+
+UINT64 gCurrentMonotonicCount = 0;
+
+EFI_STATUS
+EFIAPI
+GetNextMonotonicCount (
+ OUT UINT64 *Count
+ )
+{
+ if (Count == NULL) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ *Count = gCurrentMonotonicCount++;
+ return EFI_SUCCESS;
+}
+
+EFI_STATUS
+EFIAPI
+GetNextHighMonotonicCount (
+ OUT UINT32 *HighCount
+ )
+{
+ if (HighCount == NULL) {
+ return EFI_INVALID_PARAMETER;
+ }
+
+ gCurrentMonotonicCount += 0x0000000100000000ULL;
+
+ *HighCount = (UINT32)RShiftU64 (gCurrentMonotonicCount, 32) & 0xFFFFFFFF;
+
+ return EFI_SUCCESS;
+}
+
+
+EFI_STATUS
+EFIAPI
+MonotonicCounterDriverInitialize (
+ IN EFI_HANDLE ImageHandle,
+ IN EFI_SYSTEM_TABLE *SystemTable
+ )
+{
+ EFI_STATUS Status;
+ EFI_HANDLE Handle = NULL;
+
+ // Make sure the Monotonic Counter Architectural Protocol is not already installed in the system
+ ASSERT_PROTOCOL_ALREADY_INSTALLED(NULL, &gEfiMonotonicCounterArchProtocolGuid);
+
+ // Fill in the EFI Boot Services and EFI Runtime Services Monotonic Counter Fields
+ gBS->GetNextMonotonicCount = GetNextMonotonicCount;
+ gRT->GetNextHighMonotonicCount = GetNextHighMonotonicCount;
+
+ // Install the Monotonic Counter Architectural Protocol onto a new handle
+ Status = gBS->InstallMultipleProtocolInterfaces (
+ &Handle,
+ &gEfiMonotonicCounterArchProtocolGuid, NULL,
+ NULL
+ );
+ return Status;
+}
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