projects / mirror_edk2.git / blame
| Commit | Line | Data |
|---|---|---|
| 41aa07b3 JJ |
1 | ;------------------------------------------------------------------------------\r |
| 2 | ;\r | |
| d3febfd9 | 3 | ; Copyright (c) 2006 - 2022, Intel Corporation. All rights reserved.<BR>\r |
| 9344f092 | 4 | ; SPDX-License-Identifier: BSD-2-Clause-Patent\r |
| 41aa07b3 JJ |
5 | ;\r |
| 6 | ; Module Name:\r | |
| 7 | ;\r | |
| 8 | ; ReadDr4.Asm\r | |
| 9 | ;\r | |
| 10 | ; Abstract:\r | |
| 11 | ;\r | |
| 12 | ; AsmReadDr4 function\r | |
| 13 | ;\r | |
| 14 | ; Notes:\r | |
| 15 | ;\r | |
| 16 | ;------------------------------------------------------------------------------\r | |
| 17 | \r | |
| 18 | SECTION .text\r | |
| 19 | \r | |
| 20 | ;------------------------------------------------------------------------------\r | |
| 21 | ; UINTN\r | |
| 22 | ; EFIAPI\r | |
| 23 | ; AsmReadDr4 (\r | |
| 24 | ; VOID\r | |
| 25 | ; );\r | |
| 26 | ;------------------------------------------------------------------------------\r | |
| 27 | global ASM_PFX(AsmReadDr4)\r | |
| 28 | ASM_PFX(AsmReadDr4):\r | |
| 29 | ;\r | |
| 30 | ; DR4 is alias to DR6 only if DE (in CR4) is cleared. Otherwise, reading\r | |
| 31 | ; this register will cause a #UD exception.\r | |
| 32 | ;\r | |
| 33 | ; MS assembler doesn't support this instruction since no one would use it\r | |
| d3febfd9 | 34 | ; under normal circustances.\r |
| 41aa07b3 | 35 | ;\r |
| d3febfd9 | 36 | mov eax, dr4\r |
| 41aa07b3 JJ |
37 | ret\r |
| 38 | \r |