projects / mirror_edk2.git / blame
| Commit | Line | Data |
|---|---|---|
| d9f1cac5 HW |
1 | /** @file\r |
| 2 | SpeculationBarrier() function for IA32 and x64.\r | |
| 3 | \r | |
| aec74656 | 4 | Copyright (C) 2018 - 2019, Intel Corporation. All rights reserved.<BR>\r |
| d9f1cac5 | 5 | \r |
| 9344f092 | 6 | SPDX-License-Identifier: BSD-2-Clause-Patent\r |
| d9f1cac5 HW |
7 | \r |
| 8 | **/\r | |
| 9 | \r | |
| 10 | #include <Library/BaseLib.h>\r | |
| 11 | \r | |
| 12 | /**\r | |
| 13 | Uses as a barrier to stop speculative execution.\r | |
| 14 | \r | |
| 15 | Ensures that no later instruction will execute speculatively, until all prior\r | |
| 16 | instructions have completed.\r | |
| 17 | \r | |
| 18 | **/\r | |
| 19 | VOID\r | |
| 20 | EFIAPI\r | |
| 21 | SpeculationBarrier (\r | |
| 22 | VOID\r | |
| 23 | )\r | |
| 24 | {\r | |
| aec74656 MK |
25 | if (PcdGet8 (PcdSpeculationBarrierType) == 0x01) {\r |
| 26 | AsmLfence ();\r | |
| 27 | } else if (PcdGet8 (PcdSpeculationBarrierType) == 0x02) {\r | |
| 28 | AsmCpuid (0x01, NULL, NULL, NULL, NULL);\r | |
| 29 | }\r | |
| d9f1cac5 | 30 | }\r |