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/board/freescale/common/sdhc_boot.c

@@ -0,0 +1,76 @@
+/*
+ * Copyright 2011 Freescale Semiconductor, Inc.
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <mmc.h>
+#include <malloc.h>
+
+/*
+ * The environment variables are written to just after the u-boot image
+ * on SDCard, so we must read the MBR to get the start address and code
+ * length of the u-boot image, then calculate the address of the env.
+ */
+#define ESDHC_BOOT_IMAGE_SIZE	0x48
+#define ESDHC_BOOT_IMAGE_ADDR	0x50
+
+#define ESDHC_DEFAULT_ENVADDR	0x400
+
+int mmc_get_env_addr(struct mmc *mmc, int copy, u32 *env_addr)
+{
+	u8 *tmp_buf;
+	u32 blklen, code_offset, code_len, n;
+
+	blklen = mmc->read_bl_len;
+	tmp_buf = malloc(blklen);
+	if (!tmp_buf)
+		return 1;
+
+	/* read out the first block, get the config data information */
+	n = mmc->block_dev.block_read(&mmc->block_dev, 0, 1, tmp_buf);
+	if (!n) {
+		free(tmp_buf);
+		return 1;
+	}
+
+	/* Get the Source Address, from offset 0x50 */
+	code_offset = *(u32 *)(tmp_buf + ESDHC_BOOT_IMAGE_ADDR);
+
+	/* Get the code size from offset 0x48 */
+	code_len = *(u32 *)(tmp_buf + ESDHC_BOOT_IMAGE_SIZE);
+
+#ifdef CONFIG_ESDHC_HC_BLK_ADDR
+	/*
+	 * On soc BSC9131, BSC9132:
+	 * In High Capacity SD Cards (> 2 GBytes), the 32-bit source address and
+	 * code length of these soc specify the memory address in block address
+	 * format. Block length is fixed to 512 bytes as per the SD High
+	 * Capacity specification.
+	 */
+	u64 tmp;
+
+	if (mmc->high_capacity) {
+		tmp = (u64)code_offset * blklen;
+		tmp += code_len * blklen;
+	} else
+		tmp = code_offset + code_len;
+
+	if ((tmp + CONFIG_ENV_SIZE > mmc->capacity) ||
+			(tmp > 0xFFFFFFFFU))
+		*env_addr = ESDHC_DEFAULT_ENVADDR;
+	else
+		*env_addr = tmp;
+
+	free(tmp_buf);
+
+	return 0;
+#endif
+
+	*env_addr = code_offset + code_len;
+
+	free(tmp_buf);
+
+	return 0;
+}