MdePkg/BaseLib: Support IA32 processors without CLFLUSH

[mirror_edk2.git] / MdePkg / Library / BaseLib / Ia32 / FlushCacheLine.asm

;------------------------------------------------------------------------------\r
;\r
; Copyright (c) 2006 - 2015, Intel Corporation. All rights reserved.<BR>\r
; This program and the accompanying materials\r
; are licensed and made available under the terms and conditions of the BSD License\r
; which accompanies this distribution.  The full text of the license may be found at\r
; http://opensource.org/licenses/bsd-license.php.\r
;\r
; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
;\r
; Module Name:\r
;\r
;   FlushCacheLine.Asm\r
;\r
; Abstract:\r
;\r
;   AsmFlushCacheLine function\r
;\r
; Notes:\r
;\r
;------------------------------------------------------------------------------\r
\r
    .586P\r
    .model  flat,C\r
    .xmm\r
    .code\r
\r
;------------------------------------------------------------------------------\r
; VOID *\r
; EFIAPI\r
; AsmFlushCacheLine (\r
;   IN      VOID                      *LinearAddress\r
;   );\r
;------------------------------------------------------------------------------\r
AsmFlushCacheLine   PROC\r
    ;\r
    ; If the CPU does not support CLFLUSH instruction, \r
    ; then promote flush range to flush entire cache.\r
    ;\r
    mov     eax, 1\r
    cpuid\r
    mov     eax, [esp + 4]\r
    test    edx, BIT19\r
    jz      @F\r
    clflush [eax]\r
    ret\r
@@:\r
    wbinvd\r
    ret\r
AsmFlushCacheLine   ENDP\r
\r
    END\r