tests: add mcuboot test application

tests/mcuboot/Makefile

+APPLICATION = hello_mcuboot
+
+BOARD ?= nrf52dk
+
+include ../Makefile.tests_common
+
+BOARD_WHITELIST := nrf52dk
+
+export IMAGE_VERSION = 1.1.1+1
+
+# this test is supposed to always build the mcuboot image
+all: mcuboot
+
+include $(RIOTBASE)/Makefile.include

tests/mcuboot/README.md

+# MCUBoot test application
+This test is intended to compile a hello-world program taking into account
+the existence of the MCUBoot bootloader at the first 32K in the ROM.
+
+For this first support, a pre-compiled mynewt MCUBoot binary is downloaded at
+compile time.
+
+The goal is to produce an ELF file which is linked to be flashed at a
+`BOOTLOADER_OFFSET` offset rather than the beginning of ROM. MCUBoot also
+expects an image padded with some specific headers containing the version
+information, and TLVs with hash and signing information. This is done through
+the imgtool.py application, which is executed automatically by the build
+system.
+
+This test can be called using `make mcuboot` to produce such ELF file,
+which can also be flashed using `make flash-mcuboot`.This command also flashes
+the pre-compiled bootloader.
+
+It's also possible to build and flash MCUBoot by following the instructions on
+the MCUBoot repository either using mynewt or zephyr operating systems.

tests/mcuboot/main.c

+/*
+ * Copyright (C) 2017 Inria
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     tests
+ * @{
+ *
+ * @file
+ * @brief       MCUBoot compile test application
+ *
+ * @author      Francisco Acosta <francisco.acosta@inria.fr>
+ *
+ * @}
+ */
+
+#include <stdio.h>
+#include "cpu.h"
+
+int main(void)
+{
+    puts("Hello MCUBoot!");
+
+    printf("You are running RIOT on a(n) %s board.\n", RIOT_BOARD);
+    printf("This board features a(n) %s MCU.\n", RIOT_MCU);
+    printf("The startup address is: %p\n", (void*)SCB->VTOR);
+
+    return 0;
+}