projects / mirror_edk2.git / blame
| Commit | Line | Data |
|---|---|---|
| 7798fb83 HT |
1 | #------------------------------------------------------------------------------\r |
| 2 | #*\r | |
| 7367cc6c | 3 | #* Copyright (c) 2009 - 2018, Intel Corporation. All rights reserved.<BR>\r |
| 7798fb83 HT |
4 | #* This program and the accompanying materials\r |
| 5 | #* are licensed and made available under the terms and conditions of the BSD License\r | |
| 6 | #* which accompanies this distribution. The full text of the license may be found at\r | |
| 7 | #* http://opensource.org/licenses/bsd-license.php\r | |
| 8 | #*\r | |
| 9 | #* THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r | |
| 10 | #* WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r | |
| 11 | #*\r | |
| 12 | #*\r | |
| 13 | #------------------------------------------------------------------------------\r | |
| 14 | \r | |
| 15 | #\r | |
| 16 | # Initializes floating point units for requirement of UEFI specification.\r | |
| 17 | #\r | |
| 18 | # This function initializes floating-point control word to 0x037F (all exceptions\r | |
| 19 | # masked,double-extended-precision, round-to-nearest) and multimedia-extensions control word\r | |
| 20 | # (if supported) to 0x1F80 (all exceptions masked, round-to-nearest, flush to zero\r | |
| 21 | # for masked underflow).\r | |
| 22 | #\r | |
| 23 | ASM_GLOBAL ASM_PFX(InitializeFloatingPointUnits)\r | |
| 24 | ASM_PFX(InitializeFloatingPointUnits):\r | |
| 25 | \r | |
| 26 | #\r | |
| 27 | # Initialize floating point units\r | |
| 28 | #\r | |
| 29 | finit\r | |
| 7367cc6c | 30 | \r |
| 7798fb83 | 31 | #\r |
| 7367cc6c | 32 | # Float control word initial value:\r |
| 7798fb83 HT |
33 | # all exceptions masked, double-precision, round-to-nearest\r |
| 34 | #\r | |
| 35 | pushq $0x037F\r | |
| 7367cc6c | 36 | lea (%rsp), %rax\r |
| 7798fb83 HT |
37 | fldcw (%rax)\r |
| 38 | popq %rax\r | |
| 7367cc6c | 39 | \r |
| 7798fb83 HT |
40 | #\r |
| 41 | # Set OSFXSR bit 9 in CR4\r | |
| 42 | #\r | |
| 7367cc6c | 43 | movq %cr4, %rax\r |
| 7798fb83 HT |
44 | or $0x200, %rax\r |
| 45 | movq %rax, %cr4\r | |
| 46 | \r | |
| 47 | #\r | |
| 48 | # Multimedia-extensions control word:\r | |
| 49 | # all exceptions masked, round-to-nearest, flush to zero for masked underflow\r | |
| 7367cc6c | 50 | #\r |
| 7798fb83 HT |
51 | pushq $0x01F80\r |
| 52 | lea (%rsp), %rax\r | |
| 53 | ldmxcsr (%rax)\r | |
| 54 | popq %rax\r | |
| 7367cc6c | 55 | \r |
| 7798fb83 HT |
56 | ret\r |
| 57 | \r |