MdePkg/BaseLib: Added ARM Aarch64 architecture support

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Harry Liebel <Harry.Liebel@arm.com>
Signed-off-by: Olivier Martin <olivier.martin@arm.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>



git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@14515 6f19259b-4bc3-4df7-8a09-765794883524

MdePkg/Library/BaseLib/AArch64/GetInterruptsState.S

@@ -0,0 +1,45 @@
+#------------------------------------------------------------------------------
+#
+# GetInterruptState() function for AArch64
+#
+# Copyright (c) 2006 - 2009, Intel Corporation. All rights reserved.<BR>
+# Portions copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>
+# Portions copyright (c) 2011 - 2013, ARM Ltd. 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.
+#
+#------------------------------------------------------------------------------
+
+.text
+.p2align 2
+ASM_GLOBAL ASM_PFX(GetInterruptState)
+
+#/**
+#  Retrieves the current CPU interrupt state.
+#
+#  Returns TRUE is interrupts are currently enabled. Otherwise
+#  returns FALSE.
+#
+#  @retval TRUE  CPU interrupts are enabled.
+#  @retval FALSE CPU interrupts are disabled.
+#
+#**/
+#
+#BOOLEAN
+#EFIAPI
+#GetInterruptState (
+#  VOID
+# );
+#
+ASM_PFX(GetInterruptState):
+    mrs    x0, daif
+    tst    x0, #2            // Check if IRQ is enabled. Enabled if 0.
+    mov    w0, #0
+    mov    w1, #1
+    csel   w0, w1, w0, ne
+    ret