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/MdePkg/Library/BaseLib/X86SpeculationBarrier.c | |
| parent | e02cda008591317b1625707ff8e115a4841aa889 (diff) | |
Change-Id: Iaf8d18082d3991dec7c0ebbea540f092188eb4ec
Diffstat (limited to 'roms/edk2/MdePkg/Library/BaseLib/X86SpeculationBarrier.c')
| -rw-r--r-- | roms/edk2/MdePkg/Library/BaseLib/X86SpeculationBarrier.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/roms/edk2/MdePkg/Library/BaseLib/X86SpeculationBarrier.c b/roms/edk2/MdePkg/Library/BaseLib/X86SpeculationBarrier.c new file mode 100644 index 000000000..b28fd8de9 --- /dev/null +++ b/roms/edk2/MdePkg/Library/BaseLib/X86SpeculationBarrier.c @@ -0,0 +1,30 @@ +/** @file
+ SpeculationBarrier() function for IA32 and x64.
+
+ Copyright (C) 2018 - 2019, Intel Corporation. All rights reserved.<BR>
+
+ SPDX-License-Identifier: BSD-2-Clause-Patent
+
+**/
+
+#include <Library/BaseLib.h>
+
+/**
+ Uses as a barrier to stop speculative execution.
+
+ Ensures that no later instruction will execute speculatively, until all prior
+ instructions have completed.
+
+**/
+VOID
+EFIAPI
+SpeculationBarrier (
+ VOID
+ )
+{
+ if (PcdGet8 (PcdSpeculationBarrierType) == 0x01) {
+ AsmLfence ();
+ } else if (PcdGet8 (PcdSpeculationBarrierType) == 0x02) {
+ AsmCpuid (0x01, NULL, NULL, NULL, NULL);
+ }
+}
|