diff options
Diffstat (limited to 'src/VBox/Devices/PC/ipxe/src/arch/arm/interface/efi/efiarm_nap.c')
-rw-r--r-- | src/VBox/Devices/PC/ipxe/src/arch/arm/interface/efi/efiarm_nap.c | 53 |
1 files changed, 53 insertions, 0 deletions
diff --git a/src/VBox/Devices/PC/ipxe/src/arch/arm/interface/efi/efiarm_nap.c b/src/VBox/Devices/PC/ipxe/src/arch/arm/interface/efi/efiarm_nap.c new file mode 100644 index 00000000..9ed638e9 --- /dev/null +++ b/src/VBox/Devices/PC/ipxe/src/arch/arm/interface/efi/efiarm_nap.c @@ -0,0 +1,53 @@ +/* + * Copyright (C) 2016 Michael Brown <mbrown@fensystems.co.uk>. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of the + * License, or any later version. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA + * 02110-1301, USA. + * + * You can also choose to distribute this program under the terms of + * the Unmodified Binary Distribution Licence (as given in the file + * COPYING.UBDL), provided that you have satisfied its requirements. + */ + +FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL ); + +#include <ipxe/nap.h> +#include <ipxe/efi/efi.h> + +/** @file + * + * iPXE CPU sleeping API for EFI + * + */ + +/** + * Sleep until next interrupt + * + */ +static void efiarm_cpu_nap ( void ) { + /* + * I can't find any EFI API that allows us to put the CPU to + * sleep. The CpuSleep() function is defined in CpuLib.h, but + * isn't part of any exposed protocol so we have no way to + * call it. + * + * The EFI shell doesn't seem to bother sleeping the CPU; it + * just sits there idly burning power. + * + */ + __asm__ __volatile__ ( "wfi" ); +} + +PROVIDE_NAP ( efiarm, cpu_nap, efiarm_cpu_nap ); |