MdePkg/Library/BaseLib/X86EnablePaging64.c

   1 /** @file
   2   IA-32/x64 AsmEnablePaging64()
   3
   4   Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
   5   SPDX-License-Identifier: BSD-2-Clause-Patent
   6
   7 **/
   8
   9 #include "BaseLibInternals.h"
  10
  11 /**
  12   Enables the 64-bit paging mode on the CPU.
  13
  14   Enables the 64-bit paging mode on the CPU. CR0, CR3, CR4, and the page tables
  15   must be properly initialized prior to calling this service. This function
  16   assumes the current execution mode is 32-bit protected mode with flat
  17   descriptors. This function is only available on IA-32. After the 64-bit
  18   paging mode is enabled, control is transferred to the function specified by
  19   EntryPoint using the new stack specified by NewStack and passing in the
  20   parameters specified by Context1 and Context2. Context1 and Context2 are
  21   optional and may be 0. The function EntryPoint must never return.
  22
  23   If the current execution mode is not 32-bit protected mode with flat
  24   descriptors, then ASSERT().
  25   If EntryPoint is 0, then ASSERT().
  26   If NewStack is 0, then ASSERT().
  27
  28   @param  Cs          The 16-bit selector to load in the CS before EntryPoint
  29                       is called. The descriptor in the GDT that this selector
  30                       references must be setup for long mode.
  31   @param  EntryPoint  The 64-bit virtual address of the function to call with
  32                       the new stack after paging is enabled.
  33   @param  Context1    The 64-bit virtual address of the context to pass into
  34                       the EntryPoint function as the first parameter after
  35                       paging is enabled.
  36   @param  Context2    The 64-bit virtual address of the context to pass into
  37                       the EntryPoint function as the second parameter after
  38                       paging is enabled.
  39   @param  NewStack    The 64-bit virtual address of the new stack to use for
  40                       the EntryPoint function after paging is enabled.
  41
  42 **/
  43 VOID
  44 EFIAPI
  45 AsmEnablePaging64 (
  46   IN      UINT16  Cs,
  47   IN      UINT64  EntryPoint,
  48   IN      UINT64  Context1   OPTIONAL,
  49   IN      UINT64  Context2   OPTIONAL,
  50   IN      UINT64  NewStack
  51   )
  52 {
  53   ASSERT (EntryPoint != 0);
  54   ASSERT (NewStack != 0);
  55   InternalX86EnablePaging64 (Cs, EntryPoint, Context1, Context2, NewStack);
  56 }