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/arm/mach-sunxi/prcm.c

@@ -0,0 +1,47 @@
+/*
+ * Sunxi A31 Power Management Unit
+ *
+ * (C) Copyright 2013 Oliver Schinagl <oliver@schinagl.nl>
+ * http://linux-sunxi.org
+ *
+ * Based on sun6i sources and earlier U-Boot Allwinner A10 SPL work
+ *
+ * (C) Copyright 2006-2013
+ * Allwinner Technology Co., Ltd. <www.allwinnertech.com>
+ * Berg Xing <bergxing@allwinnertech.com>
+ * Tom Cubie <tangliang@allwinnertech.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <errno.h>
+#include <asm/io.h>
+#include <asm/arch/cpu.h>
+#include <asm/arch/prcm.h>
+#include <asm/arch/sys_proto.h>
+
+/* APB0 clock gate and reset bit offsets are the same. */
+void prcm_apb0_enable(u32 flags)
+{
+	struct sunxi_prcm_reg *prcm =
+		(struct sunxi_prcm_reg *)SUNXI_PRCM_BASE;
+
+	/* open the clock for module */
+	setbits_le32(&prcm->apb0_gate, flags);
+
+	/* deassert reset for module */
+	setbits_le32(&prcm->apb0_reset, flags);
+}
+
+void prcm_apb0_disable(u32 flags)
+{
+	struct sunxi_prcm_reg *prcm =
+		(struct sunxi_prcm_reg *)SUNXI_PRCM_BASE;
+
+	/* assert reset for module */
+	clrbits_le32(&prcm->apb0_reset, flags);
+
+	/* close the clock for module */
+	clrbits_le32(&prcm->apb0_gate, flags);
+}