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_fat.c

@@ -0,0 +1,159 @@
+/*
+ * (C) Copyright 2014
+ * Texas Instruments, <www.ti.com>
+ *
+ * Dan Murphy <dmurphy@ti.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ *
+ * FAT Image Functions copied from spl_mmc.c
+ */
+
+#include <common.h>
+#include <spl.h>
+#include <asm/u-boot.h>
+#include <fat.h>
+#include <errno.h>
+#include <image.h>
+#include <libfdt.h>
+
+static int fat_registered;
+
+#ifdef CONFIG_SPL_FAT_SUPPORT
+static int spl_register_fat_device(struct blk_desc *block_dev, int partition)
+{
+	int err = 0;
+
+	if (fat_registered)
+		return err;
+
+	err = fat_register_device(block_dev, partition);
+	if (err) {
+#ifdef CONFIG_SPL_LIBCOMMON_SUPPORT
+		printf("%s: fat register err - %d\n", __func__, err);
+#endif
+		return err;
+	}
+
+	fat_registered = 1;
+
+	return err;
+}
+
+static ulong spl_fit_read(struct spl_load_info *load, ulong file_offset,
+			  ulong size, void *buf)
+{
+	loff_t actread;
+	int ret;
+	char *filename = (char *)load->filename;
+
+	ret = fat_read_file(filename, buf, file_offset, size, &actread);
+	if (ret)
+		return ret;
+
+	return actread;
+}
+
+int spl_load_image_fat(struct blk_desc *block_dev,
+						int partition,
+						const char *filename)
+{
+	int err;
+	struct image_header *header;
+
+	err = spl_register_fat_device(block_dev, partition);
+	if (err)
+		goto end;
+
+	header = (struct image_header *)(CONFIG_SYS_TEXT_BASE -
+						sizeof(struct image_header));
+
+	err = file_fat_read(filename, header, sizeof(struct image_header));
+	if (err <= 0)
+		goto end;
+
+	if (IS_ENABLED(CONFIG_SPL_LOAD_FIT) &&
+	    image_get_magic(header) == FDT_MAGIC) {
+		struct spl_load_info load;
+
+		debug("Found FIT\n");
+		load.read = spl_fit_read;
+		load.bl_len = 1;
+		load.filename = (void *)filename;
+		load.priv = NULL;
+
+		return spl_load_simple_fit(&load, 0, header);
+	} else {
+		err = spl_parse_image_header(header);
+		if (err)
+			goto end;
+
+		err = file_fat_read(filename, (u8 *)spl_image.load_addr, 0);
+	}
+
+end:
+#ifdef CONFIG_SPL_LIBCOMMON_SUPPORT
+	if (err <= 0)
+		printf("%s: error reading image %s, err - %d\n",
+		       __func__, filename, err);
+#endif
+
+	return (err <= 0);
+}
+
+#ifdef CONFIG_SPL_OS_BOOT
+int spl_load_image_fat_os(struct blk_desc *block_dev, int partition)
+{
+	int err;
+	__maybe_unused char *file;
+
+	err = spl_register_fat_device(block_dev, partition);
+	if (err)
+		return err;
+
+#if defined(CONFIG_SPL_ENV_SUPPORT) && defined(CONFIG_SPL_OS_BOOT)
+	file = getenv("falcon_args_file");
+	if (file) {
+		err = file_fat_read(file, (void *)CONFIG_SYS_SPL_ARGS_ADDR, 0);
+		if (err <= 0) {
+			printf("spl: error reading image %s, err - %d, falling back to default\n",
+			       file, err);
+			goto defaults;
+		}
+		file = getenv("falcon_image_file");
+		if (file) {
+			err = spl_load_image_fat(block_dev, partition, file);
+			if (err != 0) {
+				puts("spl: falling back to default\n");
+				goto defaults;
+			}
+
+			return 0;
+		} else
+			puts("spl: falcon_image_file not set in environment, falling back to default\n");
+	} else
+		puts("spl: falcon_args_file not set in environment, falling back to default\n");
+
+defaults:
+#endif
+
+	err = file_fat_read(CONFIG_SPL_FS_LOAD_ARGS_NAME,
+			    (void *)CONFIG_SYS_SPL_ARGS_ADDR, 0);
+	if (err <= 0) {
+#ifdef CONFIG_SPL_LIBCOMMON_SUPPORT
+		printf("%s: error reading image %s, err - %d\n",
+		       __func__, CONFIG_SPL_FS_LOAD_ARGS_NAME, err);
+#endif
+		return -1;
+	}
+
+	return spl_load_image_fat(block_dev, partition,
+			CONFIG_SPL_FS_LOAD_KERNEL_NAME);
+}
+#else
+int spl_load_image_fat_os(struct blk_desc *block_dev, int partition)
+{
+	return -ENOSYS;
+}
+#endif
+#endif