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/common/spl/spl_nor.c

@@ -0,0 +1,72 @@
+/*
+ * Copyright (C) 2012 Stefan Roese <sr@denx.de>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <spl.h>
+
+int spl_nor_load_image(void)
+{
+	int ret;
+	/*
+	 * Loading of the payload to SDRAM is done with skipping of
+	 * the mkimage header in this SPL NOR driver
+	 */
+	spl_image.flags |= SPL_COPY_PAYLOAD_ONLY;
+
+#ifdef CONFIG_SPL_OS_BOOT
+	if (!spl_start_uboot()) {
+		const struct image_header *header;
+
+		/*
+		 * Load Linux from its location in NOR flash to its defined
+		 * location in SDRAM
+		 */
+		header = (const struct image_header *)CONFIG_SYS_OS_BASE;
+
+		if (image_get_os(header) == IH_OS_LINUX) {
+			/* happy - was a Linux */
+
+			ret = spl_parse_image_header(header);
+			if (ret)
+				return ret;
+
+			memcpy((void *)spl_image.load_addr,
+			       (void *)(CONFIG_SYS_OS_BASE +
+					sizeof(struct image_header)),
+			       spl_image.size);
+
+			/*
+			 * Copy DT blob (fdt) to SDRAM. Passing pointer to
+			 * flash doesn't work (16 KiB should be enough for DT)
+			 */
+			memcpy((void *)CONFIG_SYS_SPL_ARGS_ADDR,
+			       (void *)(CONFIG_SYS_FDT_BASE),
+			       (16 << 10));
+
+			return 0;
+		} else {
+			puts("The Expected Linux image was not found.\n"
+			     "Please check your NOR configuration.\n"
+			     "Trying to start u-boot now...\n");
+		}
+	}
+#endif
+
+	/*
+	 * Load real U-Boot from its location in NOR flash to its
+	 * defined location in SDRAM
+	 */
+	ret = spl_parse_image_header(
+			(const struct image_header *)CONFIG_SYS_UBOOT_BASE);
+	if (ret)
+		return ret;
+
+	memcpy((void *)(unsigned long)spl_image.load_addr,
+	       (void *)(CONFIG_SYS_UBOOT_BASE + sizeof(struct image_header)),
+	       spl_image.size);
+
+	return 0;
+}