AccessMsr.s revision 4fd606d1f5abe38e1f42c38de1d2e895166bd0f4
/// @file
/// IPF specific Machine Specific Registers accessing functions.
///
/// Copyright (c) 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.
///
///
///
//---------------------------------------------------------------------------------
//++
// AsmReadMsr
//
// Reads the current value of a Machine Specific Register (MSR).
//
// Reads and returns the current value of the Machine Specific Register specified by Index. No
// parameter checking is performed on Index, and if the Index value is beyond the implemented MSR
// register range, a Reserved Register/Field fault may occur. The caller must either guarantee that
// Index is valid, or the caller must set up fault handlers to catch the faults. This function is
// only available on IPF.
//
// Arguments :
//
// On Entry : The 8-bit Machine Specific Register index to read.
//
// Return Value: The current value of the Machine Specific Register specified by Index.
//
//--
//----------------------------------------------------------------------------------
.text
.type AsmReadMsr, @function
.proc AsmReadMsr
.regstk 1, 0, 0, 0
AsmReadMsr::
mov r8=msr[in0];;
br.ret.sptk b0;;
.endp AsmReadMsr
//---------------------------------------------------------------------------------
//++
// AsmWriteMsr
//
// Writes the current value of a Machine Specific Register (MSR).
//
// Writes Value to the Machine Specific Register specified by Index. Value is returned. No
// parameter checking is performed on Index, and if the Index value is beyond the implemented MSR
// register range, a Reserved Register/Field fault may occur. The caller must either guarantee that
// Index is valid, or the caller must set up fault handlers to catch the faults. This function is
// only available on IPF.
//
// Arguments :
//
// On Entry : The 8-bit Machine Specific Register index to write.
// The 64-bit value to write to the Machine Specific Register.
//
// Return Value: The 64-bit value to write to the Machine Specific Register.
//
//--
//----------------------------------------------------------------------------------
.text
.type AsmWriteMsr, @function
.proc AsmWriteMsr
.regstk 2, 0, 0, 0
AsmWriteMsr::
mov msr[in0] = in1
mov r8 = in1;;
srlz.d;;
br.ret.sptk b0;;
.endp AsmWriteMsr