1 files changed, 49 insertions, 0 deletions
diff --git a/qemu/roms/ipxe/src/arch/x86/interface/efi/efix86_nap.c b/qemu/roms/ipxe/src/arch/x86/interface/efi/efix86_nap.c
new file mode 100644
index 000000000..b05421fab
--- /dev/null
+++ b/qemu/roms/ipxe/src/arch/x86/interface/efi/efix86_nap.c
@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2008 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.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+#include <ipxe/nap.h>
+#include <ipxe/efi/efi.h>
+
+/** @file
+ *
+ * iPXE CPU sleeping API for EFI
+ *
+ */
+
+/**
+ * Sleep until next interrupt
+ *
+ */
+static void efix86_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__ ( "hlt" );
+}
+
+PROVIDE_NAP ( efix86, cpu_nap, efix86_cpu_nap );