UnixPkg/Sec/X64/SwitchStack.S

   1 #------------------------------------------------------------------------------
   2 #
   3 # Copyright (c) 2006 - 2008, Intel Corporation. All rights reserved.<BR>
   4 # This program and the accompanying materials
   5 # are licensed and made available under the terms and conditions of the BSD License
   6 # which accompanies this distribution.  The full text of the license may be found at
   7 # http://opensource.org/licenses/bsd-license.php.
   8 #
   9 # THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  10 # WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  11 #
  12 # Module Name:
  13 #
  14 #   SwitchStack.S
  15 #
  16 # Abstract:
  17 #
  18 #------------------------------------------------------------------------------
  19
  20
  21 #------------------------------------------------------------------------------
  22 # Routine Description:
  23 #
  24 #   Routine for switching stacks with 3 parameters EFI ABI
  25 #   Convert UNIX to EFI ABI
  26 #
  27 # Arguments:
  28 #
  29 #   (rdi) EntryPoint    - Entry point with new stack.
  30 #   (rsi) Context1      - Parameter1 for entry point. (rcx)
  31 #   (rdx) Context2      - Parameter2 for entry point. (rdx)
  32 #   (rcx) Context3      - Parameter3 for entry point. (r8)
  33 #   (r8)  NewStack      - The pointer to new stack.
  34 #
  35 # Returns:
  36 #
  37 #   None
  38 #
  39 #------------------------------------------------------------------------------
  40 ASM_GLOBAL ASM_PFX(PeiSwitchStacks)
  41 ASM_PFX(PeiSwitchStacks):
  42     pushq   %rbp            // stack frame is for the debugger
  43     movq    %rsp, %rbp
  44
  45     movq    %r8,  %rsp
  46
  47     movq    %rdi, %rax
  48     movq    %rsi, %rcx
  49     movq    %rcx, %r8
  50
  51     #
  52     # Reserve space for register parameters (rcx, rdx, r8 & r9) on the stack,
  53     # in case the callee wishes to spill them.
  54     #
  55     subq    $32, %rsp  // 32-byte shadow space plus alignment pad
  56     call    *%rax
  57
  58
  59 #------------------------------------------------------------------------------
  60 # Routine Description:
  61 #
  62 #   Routine for switching stacks with 3 parameters UNIX ABI
  63 #
  64 # Arguments:
  65 #
  66 #   (rdi) EntryPoint    - Entry point with new stack.
  67 #   (rsi) Context1      - Parameter1 for entry point.
  68 #   (rdx) Context2      - Parameter2 for entry point.
  69 #   (rcx) Context3      - Parameter3 for entry point.
  70 #   (r8)  NewStack      - The pointer to new stack.
  71 #
  72 # Returns:
  73 #
  74 #   None
  75 #
  76 #------------------------------------------------------------------------------
  77 ASM_GLOBAL ASM_PFX(UnixPeiSwitchStacks)
  78 ASM_PFX(UnixPeiSwitchStacks):
  79     pushq   %rbp            // stack frame is for the debugger
  80     movq    %rsp, %rbp
  81
  82     mov     %rdi, %rax
  83     mov     %rsi, %rdi
  84     mov     %rdx, %rsi
  85     mov     %rcx, %rdx
  86     mov     %r8,  %rsp
  87
  88
  89     #
  90     # Reserve space for redzone on the stack,
  91     # in case the callee wishes to spill them.
  92     #
  93     lea     -0x80(%rsp), %rsp
  94     call    *%rax
  95
  96
  97
  98 #------------------------------------------------------------------------------
  99 # VOID
 100 # EFIAPI
 101 # SecSwitchStack (
 102 #   UINT32   TemporaryMemoryBase, // Rcx, Rdi
 103 #   UINT32   PermenentMemoryBase  // Rdx, Rsi
 104 #   );
 105 #------------------------------------------------------------------------------
 106 ASM_GLOBAL ASM_PFX(SecSwitchStack)
 107 ASM_PFX(SecSwitchStack):
 108   pushq   %rbp            // stack frame is for the debugger
 109   movq    %rsp, %rbp
 110
 111   mov     %rsp, %rax
 112   sub     %rdi, %rax
 113   add     %rsi, %rax
 114   mov    (%rip), %r10
 115   mov    %r10, (%rax)
 116
 117   popq   %rbp
 118   ret
 119
 120