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-tegra/spl.c

@@ -0,0 +1,49 @@
+/*
+ * (C) Copyright 2012
+ * NVIDIA Inc, <www.nvidia.com>
+ *
+ * Allen Martin <amartin@nvidia.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+#include <common.h>
+#include <spl.h>
+
+#include <asm/io.h>
+#include <asm/arch/clock.h>
+#include <asm/arch/pinmux.h>
+#include <asm/arch/tegra.h>
+#include <asm/arch-tegra/apb_misc.h>
+#include <asm/arch-tegra/board.h>
+#include <asm/spl.h>
+#include "cpu.h"
+
+void spl_board_init(void)
+{
+	struct apb_misc_pp_ctlr *apb_misc =
+				(struct apb_misc_pp_ctlr *)NV_PA_APB_MISC_BASE;
+
+	/* enable JTAG */
+	writel(0xC0, &apb_misc->cfg_ctl);
+
+	board_init_uart_f();
+
+	/* Initialize periph GPIOs */
+	gpio_early_init_uart();
+
+	clock_early_init();
+	preloader_console_init();
+}
+
+u32 spl_boot_device(void)
+{
+	return BOOT_DEVICE_RAM;
+}
+
+void __noreturn jump_to_image_no_args(struct spl_image_info *spl_image)
+{
+	debug("image entry point: 0x%X\n", spl_image->entry_point);
+
+	start_cpu((u32)spl_image->entry_point);
+	halt_avp();
+}