1 files changed, 52 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseLib/Ia32/EnablePaging32.S b/MdePkg/Library/BaseLib/Ia32/EnablePaging32.S
new file mode 100644
index 000000000000..2449556c45df
--- /dev/null
+++ b/MdePkg/Library/BaseLib/Ia32/EnablePaging32.S
@@ -0,0 +1,52 @@
+#------------------------------------------------------------------------------
+#
+# Copyright (c) 2006 - 2008, 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.
+#
+# Module Name:
+#
+#   EnablePaging32.S
+#
+# Abstract:
+#
+#   InternalX86EnablePaging32 function
+#
+# Notes:
+#
+#------------------------------------------------------------------------------
+
+ASM_GLOBAL ASM_PFX(InternalX86EnablePaging32)
+
+#------------------------------------------------------------------------------
+# VOID
+# EFIAPI
+# InternalX86EnablePaging32 (
+#   IN      SWITCH_STACK_ENTRY_POINT  EntryPoint,
+#   IN      VOID                      *Context1,    OPTIONAL
+#   IN      VOID                      *Context2,    OPTIONAL
+#   IN      VOID                      *NewStack
+#   );
+#------------------------------------------------------------------------------
+ASM_PFX(InternalX86EnablePaging32):
+    movl    4(%esp), %ebx
+    movl    8(%esp), %ecx
+    movl    12(%esp), %edx
+    pushfl
+    pop     %edi                        # save flags in edi
+    cli
+    movl    %cr0, %eax
+    btsl    $31, %eax
+    movl    16(%esp), %esp
+    movl    %eax, %cr0
+    push    %edi
+    popfl                               # restore flags
+    push    %edx
+    push    %ecx
+    call    *%ebx
+    jmp     .