audk/MdePkg/Library/BaseLib/Ipf/AccessPsr.s

111 lines
3.3 KiB
ArmAsm

/// @file
/// IPF specific Processor Status Register accessing functions
///
/// Copyright (c) 2006, Intel Corporation
/// All rights reserved. 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: AccessPsr.s
///
///
#define CpuModeMask 0x0000001008020000
#define CpuInVirtualMode 0x1
#define CpuInPhysicalMode 0x0
#define CpuInMixMode (0x0 - 0x1)
//---------------------------------------------------------------------------------
//++
// AsmReadPsr
//
// This routine is used to read the current value of Processor Status Register (PSR).
//
// Arguments :
//
// On Entry :
//
// Return Value: The current PSR value.
//
//--
//----------------------------------------------------------------------------------
.text
.type AsmReadPsr, @function
.proc AsmReadPsr
AsmReadPsr::
mov r8 = psr;;
br.ret.dpnt b0;;
.endp AsmReadPsr
//---------------------------------------------------------------------------------
//++
// AsmWritePsr
//
// This routine is used to write the value of Processor Status Register (PSR).
//
// Arguments :
//
// On Entry : The value need to be written.
//
// Return Value: The value have been written.
//
//--
//----------------------------------------------------------------------------------
.text
.type AsmWritePsr, @function
.proc AsmWritePsr
.regstk 1, 0, 0, 0
AsmWritePsr::
mov psr.l = in0
mov r8 = in0;;
srlz.d;;
srlz.i;;
br.ret.dpnt b0;;
.endp AsmWritePsr
//---------------------------------------------------------------------------------
//++
// AsmCpuVirtual
//
// This routine is used to determines if the CPU is currently executing
// in virtual, physical, or mixed mode.
//
// If the CPU is in virtual mode(PSR.RT=1, PSR.DT=1, PSR.IT=1), then 1 is returned.
// If the CPU is in physical mode(PSR.RT=0, PSR.DT=0, PSR.IT=0), then 0 is returned.
// If the CPU is not in physical mode or virtual mode, then it is in mixed mode,
// and -1 is returned.
//
// Arguments:
//
// On Entry: None
//
// Return Value: The CPU mode flag
// return 1 The CPU is in virtual mode.
// return 0 The CPU is in physical mode.
// return -1 The CPU is in mixed mode.
//
//--
//----------------------------------------------------------------------------------
.text
.type AsmCpuVirtual, @function
.proc AsmCpuVirtual
AsmCpuVirtual::
mov r29 = psr
movl r30 = CpuModeMask;;
and r28 = r30, r29;;
cmp.eq p6, p7 = r30, r28;;
(p6) mov r8 = CpuInVirtualMode;;
(p7) cmp.eq p6, p7 = 0x0, r28;;
(p6) mov r8 = CpuInPhysicalMode;;
(p7) mov r8 = CpuInMixMode;;
br.ret.dpnt b0;;
.endp AsmCpuVirtual