UefiCpuPkg BaseUefiCpuLib: Convert Ia32/InitializeFpu.asm to NASM

The BaseTools/Scripts/ConvertMasmToNasm.py script was used to convert
Ia32/InitializeFpu.asm to Ia32/InitializeFpu.nasm.
And, manually add .rdata section.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Liming Gao <liming.gao@intel.com>
This commit is contained in:
Liming Gao 2016-06-14 15:58:31 +08:00
parent b85a6ffb44
commit f893042d05
1 changed files with 74 additions and 0 deletions

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;------------------------------------------------------------------------------
;*
;* Copyright (c) 2016, Intel Corporation. All rights reserved.<BR>
;* This program and the accompanying materials
;* are licensed and made available under the terms and conditions of the BSD License
;* which accompanies this distribution. The full text of the license may be found at
;* http://opensource.org/licenses/bsd-license.php
;*
;* THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
;* WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
;*
;*
;------------------------------------------------------------------------------
SECTION .rdata
;
; Float control word initial value:
; all exceptions masked, double-precision, round-to-nearest
;
mFpuControlWord: DW 0x27F
;
; Multimedia-extensions control word:
; all exceptions masked, round-to-nearest, flush to zero for masked underflow
;
mMmxControlWord: DD 0x1F80
SECTION .text
;
; Initializes floating point units for requirement of UEFI specification.
;
; This function initializes floating-point control word to 0x027F (all exceptions
; masked,double-precision, round-to-nearest) and multimedia-extensions control word
; (if supported) to 0x1F80 (all exceptions masked, round-to-nearest, flush to zero
; for masked underflow).
;
global ASM_PFX(InitializeFloatingPointUnits)
ASM_PFX(InitializeFloatingPointUnits):
push ebx
;
; Initialize floating point units
;
finit
fldcw [mFpuControlWord]
;
; Use CpuId instructuion (CPUID.01H:EDX.SSE[bit 25] = 1) to test
; whether the processor supports SSE instruction.
;
mov eax, 1
cpuid
bt edx, 25
jnc Done
;
; Set OSFXSR bit 9 in CR4
;
mov eax, cr4
or eax, BIT9
mov cr4, eax
;
; The processor should support SSE instruction and we can use
; ldmxcsr instruction
;
ldmxcsr [mMmxControlWord]
Done:
pop ebx
ret