MdePkg/Library/BaseLib/X64/Pvalidate.nasm

   1 ;-----------------------------------------------------------------------------
   2 ;
   3 ; Copyright (c) 2021, AMD. All rights reserved.<BR>
   4 ; SPDX-License-Identifier: BSD-2-Clause-Patent
   5 ;
   6 ;-----------------------------------------------------------------------------
   7
   8 %include "Nasm.inc"
   9
  10     SECTION .text
  11
  12 ;-----------------------------------------------------------------------------
  13 ;  UINT32
  14 ;  EFIAPI
  15 ;  AsmPvalidate (
  16 ;    IN   UINT32              PageSize
  17 ;    IN   UINT32              Validate,
  18 ;    IN   UINT64              Address
  19 ;    )
  20 ;-----------------------------------------------------------------------------
  21 global ASM_PFX(AsmPvalidate)
  22 ASM_PFX(AsmPvalidate):
  23   mov     rax, r8
  24
  25   PVALIDATE
  26
  27   ; Save the carry flag.
  28   setc    dl
  29
  30   ; The PVALIDATE instruction returns the status in rax register.
  31   cmp     rax, 0
  32   jne     PvalidateExit
  33
  34   ; Check the carry flag to determine if RMP entry was updated.
  35   cmp     dl, 0
  36   je      PvalidateExit
  37
  38   ; Return the PVALIDATE_RET_NO_RMPUPDATE.
  39   mov     rax, 255
  40
  41 PvalidateExit:
  42   ret