Fixed incorrect syntax for immediate HEX value.

[mirror_edk2.git] / UefiCpuPkg / Library / BaseUefiCpuLib / X64 / InitializeFpu.S

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#
# 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).
#
ASM_GLOBAL ASM_PFX(InitializeFloatingPointUnits)
ASM_PFX(InitializeFloatingPointUnits):

    #
    # Initialize floating point units
    #
    finit
    
    #
    # Float control word initial value: 
    # all exceptions masked, double-precision, round-to-nearest
    #
    pushq   $0x027F
    lea     (%rsp), %rax 
    fldcw   (%rax)
    popq    %rax
    
    #
    # Set OSFXSR bit 9 in CR4
    #
    movq    %cr4, %rax 
    or      $0x200, %rax
    movq    %rax, %cr4

    #
    # Multimedia-extensions control word:
    # all exceptions masked, round-to-nearest, flush to zero for masked underflow
    #    
    pushq   $0x01F80
    lea     (%rsp), %rax
    ldmxcsr (%rax)
    popq    %rax
    
    ret