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/drivers/bootcount/bootcount_at91.c

@@ -0,0 +1,31 @@
+/*
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/at91_gpbr.h>
+
+/*
+ * We combine the BOOTCOUNT_MAGIC and bootcount in one 32-bit register.
+ * This is done so we need to use only one of the four GPBR registers.
+ */
+void bootcount_store(ulong a)
+{
+	at91_gpbr_t *gpbr = (at91_gpbr_t *) ATMEL_BASE_GPBR;
+
+	writel((BOOTCOUNT_MAGIC & 0xffff0000) | (a & 0x0000ffff),
+		&gpbr->reg[AT91_GPBR_INDEX_BOOTCOUNT]);
+}
+
+ulong bootcount_load(void)
+{
+	at91_gpbr_t *gpbr = (at91_gpbr_t *) ATMEL_BASE_GPBR;
+
+	ulong val = readl(&gpbr->reg[AT91_GPBR_INDEX_BOOTCOUNT]);
+	if ((val & 0xffff0000) != (BOOTCOUNT_MAGIC & 0xffff0000))
+		return 0;
+	else
+		return val & 0x0000ffff;
+}