audk/MdePkg/Library/BaseLib/AArch64/GetInterruptsState.asm
Michael D Kinney 9344f09215 MdePkg: Replace BSD License with BSD+Patent License
https://bugzilla.tianocore.org/show_bug.cgi?id=1373

Replace BSD 2-Clause License with BSD+Patent License.  This change is
based on the following emails:

  https://lists.01.org/pipermail/edk2-devel/2019-February/036260.html
  https://lists.01.org/pipermail/edk2-devel/2018-October/030385.html

RFCs with detailed process for the license change:

  V3: https://lists.01.org/pipermail/edk2-devel/2019-March/038116.html
  V2: https://lists.01.org/pipermail/edk2-devel/2019-March/037669.html
  V1: https://lists.01.org/pipermail/edk2-devel/2019-March/037500.html

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Michael D Kinney <michael.d.kinney@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
2019-04-09 10:58:13 -07:00

44 lines
1.1 KiB
NASM

;------------------------------------------------------------------------------
;
; 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>
; SPDX-License-Identifier: BSD-2-Clause-Patent
;
;------------------------------------------------------------------------------
EXPORT GetInterruptState
AREA BaseLib_LowLevel, CODE, READONLY
DAIF_RD_IRQ_BIT EQU (1 << 7)
;/**
; 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
; );
;
GetInterruptState
mrs x0, daif
mov w0, wzr
tst x0, #DAIF_RD_IRQ_BIT // Check IRQ mask; set Z=1 if clear/unmasked
bne exit // if Z=1 (eq) return 1, else 0
mov w0, #1
exit
ret
END