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/openrisc/lib/bootm.c

@@ -0,0 +1,74 @@
+/*
+ * (C) Copyright 2011 Stefan Kristiansson <stefan.kristiansson@saunalahti.fi>
+ *
+ * Based on microblaze implementation by:
+ * (C) Copyright 2007 Michal Simek
+ * (C) Copyright 2004 Atmark Techno, Inc.
+ *
+ * Michal  SIMEK <monstr@monstr.eu>
+ * Yasushi SHOJI <yashi@atmark-techno.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <command.h>
+#include <image.h>
+#include <u-boot/zlib.h>
+#include <asm/byteorder.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+int do_bootm_linux(int flag, int argc, char * const argv[],
+			bootm_headers_t *images)
+{
+	void	(*kernel) (unsigned int);
+	ulong	rd_data_start, rd_data_end;
+
+	/*
+	 * allow the PREP bootm subcommand, it is required for bootm to work
+	 */
+	if (flag & BOOTM_STATE_OS_PREP)
+		return 0;
+
+	if ((flag != 0) && (flag != BOOTM_STATE_OS_GO))
+		return 1;
+
+	int	ret;
+
+	char	*of_flat_tree = NULL;
+#if defined(CONFIG_OF_LIBFDT)
+	/* did generic code already find a device tree? */
+	if (images->ft_len)
+		of_flat_tree = images->ft_addr;
+#endif
+
+	kernel = (void (*)(unsigned int))images->ep;
+
+	/* find ramdisk */
+	ret = boot_get_ramdisk(argc, argv, images, IH_ARCH_OPENRISC,
+			&rd_data_start, &rd_data_end);
+	if (ret)
+		return 1;
+
+	show_boot_progress(15);
+
+	if (!of_flat_tree && argc > 1)
+		of_flat_tree = (char *)simple_strtoul(argv[1], NULL, 16);
+#ifdef DEBUG
+	printf("## Transferring control to Linux (at address 0x%08lx) " \
+				"ramdisk 0x%08lx, FDT 0x%08lx...\n",
+		(ulong) kernel, rd_data_start, (ulong) of_flat_tree);
+#endif
+	if (dcache_status() || icache_status())
+		flush_cache((ulong)kernel, max(checkdcache(), checkicache()));
+
+	/*
+	 * Linux Kernel Parameters (passing device tree):
+	 * r3: pointer to the fdt, followed by the board info data
+	 */
+	kernel((unsigned int) of_flat_tree);
+	/* does not return */
+
+	return 1;
+}