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-meson/sm.c

@@ -0,0 +1,57 @@
+/*
+ * (C) Copyright 2016 Beniamino Galvani <b.galvani@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ *
+ * Secure monitor calls.
+ */
+
+#include <common.h>
+#include <asm/arch/gxbb.h>
+#include <linux/kernel.h>
+
+#define FN_GET_SHARE_MEM_INPUT_BASE	0x82000020
+#define FN_GET_SHARE_MEM_OUTPUT_BASE	0x82000021
+#define FN_EFUSE_READ			0x82000030
+#define FN_EFUSE_WRITE			0x82000031
+
+static void *shmem_input;
+static void *shmem_output;
+
+static void meson_init_shmem(void)
+{
+	struct pt_regs regs;
+
+	if (shmem_input && shmem_output)
+		return;
+
+	regs.regs[0] = FN_GET_SHARE_MEM_INPUT_BASE;
+	smc_call(&regs);
+	shmem_input = (void *)regs.regs[0];
+
+	regs.regs[0] = FN_GET_SHARE_MEM_OUTPUT_BASE;
+	smc_call(&regs);
+	shmem_output = (void *)regs.regs[0];
+
+	debug("Secure Monitor shmem: 0x%p 0x%p\n", shmem_input, shmem_output);
+}
+
+ssize_t meson_sm_read_efuse(uintptr_t offset, void *buffer, size_t size)
+{
+	struct pt_regs regs;
+
+	meson_init_shmem();
+
+	regs.regs[0] = FN_EFUSE_READ;
+	regs.regs[1] = offset;
+	regs.regs[2] = size;
+
+	smc_call(&regs);
+
+	if (regs.regs[0] == 0)
+		return -1;
+
+	memcpy(buffer, shmem_output, min(size, regs.regs[0]));
+
+	return regs.regs[0];
+}