MdePkg/Library/BaseLib/Ipf/AccessMsrDb.s

   1 /// @file
   2 ///  IPF specific Machine Specific Registers accessing functions.
   3 ///  This implementation uses raw data to prepresent the assembly instruction of
   4 /// mov msr[]= and mov =msr[].
   5 ///
   6 /// Copyright (c) 2008, Intel Corporation
   7 /// All rights reserved. This program and the accompanying materials
   8 /// are licensed and made available under the terms and conditions of the BSD License
   9 /// which accompanies this distribution.  The full text of the license may be found at
  10 /// http://opensource.org/licenses/bsd-license.php
  11 ///
  12 /// THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
  13 /// WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
  14 ///
  15 ///
  16 ///
  17
  18
  19 //---------------------------------------------------------------------------------
  20 //++
  21 // AsmReadMsr
  22 //
  23 // Reads the current value of a Machine Specific Register (MSR).
  24 //
  25 // Reads and returns the current value of the Machine Specific Register specified by Index.  No
  26 // parameter checking is performed on Index, and if the Index value is beyond the implemented MSR
  27 // register range, a Reserved Register/Field fault may occur.  The caller must either guarantee that
  28 // Index is valid, or the caller must set up fault handlers to catch the faults.  This function is
  29 // only available on IPF.
  30 //
  31 // Arguments :
  32 //
  33 // On Entry : The 8-bit Machine Specific Register index to read.
  34 //
  35 // Return Value: The current value of the Machine Specific Register specified by Index.
  36 //
  37 //--
  38 //----------------------------------------------------------------------------------
  39 .text
  40 .type   AsmReadMsr, @function
  41 .proc   AsmReadMsr
  42 .regstk 1, 0, 0, 0
  43
  44 AsmReadMsr::
  45 //
  46 // The follow 16 bytes stand for the bundle of
  47 //   mov    r8=msr[in0];;
  48 // since MSFT tool chain does not support mov =msr[] instruction
  49 //
  50   data1 0x0D
  51   data1 0x40
  52   data1 0x00
  53   data1 0x40
  54   data1 0x16
  55   data1 0x04
  56   data1 0x00
  57   data1 0x00
  58   data1 0x00
  59   data1 0x02
  60   data1 0x00
  61   data1 0x00
  62   data1 0x00
  63   data1 0x00
  64   data1 0x04
  65   data1 0x00
  66   br.ret.sptk  b0;;
  67 .endp   AsmReadMsr
  68
  69 //---------------------------------------------------------------------------------
  70 //++
  71 // AsmWriteMsr
  72 //
  73 // Writes the current value of a Machine Specific Register (MSR).
  74 //
  75 // Writes Value to the Machine Specific Register specified by Index.  Value is returned.  No
  76 // parameter checking is performed on Index, and if the Index value is beyond the implemented MSR
  77 // register range, a Reserved Register/Field fault may occur.  The caller must either guarantee that
  78 // Index is valid, or the caller must set up fault handlers to catch the faults.  This function is
  79 // only available on IPF.
  80 //
  81 // Arguments :
  82 //
  83 // On Entry : The 8-bit Machine Specific Register index to write.
  84 //            The 64-bit value to write to the Machine Specific Register.
  85 //
  86 // Return Value: The 64-bit value to write to the Machine Specific Register.
  87 //
  88 //--
  89 //----------------------------------------------------------------------------------
  90 .text
  91 .type   AsmWriteMsr, @function
  92 .proc   AsmWriteMsr
  93 .regstk 2, 0, 0, 0
  94
  95 AsmWriteMsr::
  96 //
  97 // The follow 16 bytes stand for the bundle of
  98 //  mov             msr[in0] = in1
  99 //  mov             r8 = in1;;
 100 // since MSFT tool chain does not support mov msr[]= instruction
 101 //
 102   data1 0x0D
 103   data1 0x00
 104   data1 0x84
 105   data1 0x40
 106   data1 0x06
 107   data1 0x04
 108   data1 0x00
 109   data1 0x00
 110   data1 0x00
 111   data1 0x02
 112   data1 0x00
 113   data1 0x00
 114   data1 0x01
 115   data1 0x08
 116   data1 0x01
 117   data1 0x84
 118   srlz.d;;
 119   br.ret.sptk     b0;;
 120 .endp   AsmWriteMsr
 121