avionic design with actual uboot and tooling

submodule of avionic design uboot bootloader and with included tools to
get you started , read readme.md and readme-tk1-loader.md

u-boot/arch/arm/mach-keystone/cmd_poweroff.c

@@ -0,0 +1,28 @@
+/*
+ * Keystone EVM : Power off
+ *
+ * (C) Copyright 2014
+ *     Texas Instruments Incorporated, <www.ti.com>
+ *
+ * SPDX-License-Identifier:     GPL-2.0+
+ */
+
+#include <common.h>
+#include <command.h>
+#include <asm/arch/mon.h>
+#include <asm/arch/psc_defs.h>
+#include <asm/arch/hardware.h>
+
+int do_poweroff(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+	mon_power_off(0);
+
+	psc_disable_module(KS2_LPSC_TETRIS);
+	psc_disable_domain(KS2_TETRIS_PWR_DOMAIN);
+
+	asm volatile ("isb\n"
+		      "dsb\n"
+		      "wfi\n");
+
+	return 0;
+}