contiki/platform/galileo

Intel Galileo Board

This README file contains general information about the Intel Galileo board support. In the following lines you will find information about supported features as well as instructions on how to build, run and debug applications for this platform. The instructions were only test in Linux environment.

Requirements

In order to build and debug the following packages must be installed in your system:

• gcc
• gdb
• openocd

Moreover, in order to debug via JTAG or serial console, you will some extra devices as described in [1] and [2].

Features

This section presents the features currently supported (e.g. device drivers and Contiki APIs) by the Galileo port.

Device drivers:

• Programmable Interrupt Controller (PIC)
• Programmable Intergal Timer (PIT)
• Real-Time Clock (RTC)
• UART
• Ethernet
• I2C
• GPIO (default pinmux configuration is listed in platform/galileo/drivers/galileo-pinmux.c)
• Intel Quark X1000 SoC message bus
• Isolated Memory Regions (IMRs)

Contiki APIs:

• Clock module
• Timer, Stimer, Etimer, Ctimer, and Rtimer libraries

Standard APIs:

• Stdio library (stdout and stderr only). Console output through UART 1 device (connected to Galileo Gen2 FTDI header)

Optional support for protection domains is also implemented and is described in cpu/x86/mm/README.md.

Preparation

Prerequisites on all Ubuntu Linux systems include texinfo and uuid-dev. Additional prerequisites on 64-bit Ubuntu Linux systems include gcc-multilib and g++-multilib.

Docker can optionally be used to prepare an Ubuntu-based, containerized build environment. This has been tested with Docker installed on Microsoft Windows 10.

If not using a containerized environment, proceed to the "Building" section below.

Using a Docker-based environment on Windows requires that the repository has been checked out with Git configured to preserve UNIX-style line endings. This can be accomplished by changing the 'core.autocrlf' setting prior to cloning the repository [5]:

git config --global core.autocrlf input

Note that this is a global setting, so it may affect other Git operations.

The drive containing the repository needs to be shared with Docker containers for the following steps to work [6]. Note that this is a global setting that affects other containers that may be present on the host.

Open Microsoft PowerShell and navigate to the base directory of the repository. Run the following command to create the build environment:

docker build -t contiki-galileo-build platform/galileo/bsp/docker

This creates a container named 'contiki-galileo-build' based on Ubuntu and installs development tools in the container.

The build commands shown below can be run within the newly-created container. To obtain a shell, run the following command in PowerShell from the base directory of the repository.

docker run -t -i -v ${Pwd}:/contiki contiki-galileo-build

This command mounts the current directory and its subdirectories at the path '/contiki' within the container. Changes to those files in the container are visible to the host and vice versa. However, changes to the container filesystem are not automatically persisted when the container is stopped.

The containerized build environment does not currently support building the Grub bootloader nor debugging using the instructions in this document.

See the Docker Overview for more information about working with containers [7].

Building

To build applications for this platform you should first build newlib (in case it wasn't already built). To build newlib you can run the following command:

$ ./platform/galileo/bsp/libc/build_newlib.sh

Once newlib is built, you are ready to build applications. By default, the following steps will use gcc as the C compiler and to invoke the linker. To use LLVM clang instead, change the values for both the CC and LD variables in cpu/x86/Makefile.x86_common to 'clang'.

To build applications for the Galileo platform you should set the TARGET variable to 'galileo'. For instance, building the hello-world application should look like this:

$ cd examples/hello-world/ && make TARGET=galileo

This will generate the 'hello-world.galileo' file which is a multiboot- compliant [3] ELF image. This image contains debugging information and it should be used in your daily development.

You can also build a "Release" image by setting the BUILD_RELEASE variable to

1. This will generate a Contiki stripped-image optimized for size.

$ cd examples/hello-world/ && make TARGET=galileo BUILD_RELEASE=1

To also generate an '.galileo.efi' file which is a UEFI [4] image, you can run the following command prior to building applications:

$ cpu/x86/uefi/build_uefi.sh

To restrict DMA so that peripherals are blocked from accessing memory regions that do not contain any data that needs to be DMA-accessible, specify X86_CONF_RESTRICT_DMA=1 as a command-line argument to the make command that is used to build the image. This will configure and lock the IMRs.

Running

You will need a multiboot-compliant bootloader to boot Contiki images in that format. However, this is not needed for booting UEFI images.

In the bsp directory, we provide a helper script which builds the Grub bootloader with multiboot support. To build the bootloader, just run the following command:

$ platform/galileo/bsp/grub/build_grub.sh

Once Grub is built, we have three main steps to run Contiki applications: prepare SDcard, connect to console, and boot image. Below follows detailed instructions.

Prepare SDcard

The instructions in this section are for a native Linux development environment, so equivalent operations should be substituted when using some other environment (e.g. Windows Explorer can be used to perform equivalent operations when using Docker on Windows as a development environment).

Mount the sdcard in directory /mnt/sdcard.

Create UEFI boot directory:

$ mkdir -p /mnt/sdcard/efi/boot

Approach for Multiboot-compliant ELF Image

Copy Contiki binary image to sdcard

$ cp examples/hello-world/hello-world.galileo /mnt/sdcard

Copy grub binary to sdcard

$ cp platform/galileo/bsp/grub/bin/grub.efi /mnt/sdcard/efi/boot/bootia32.efi

Approach for UEFI Image

Copy Contiki binary image to sdcard:

$ cp examples/hello-world/hello-world.galileo.efi /mnt/sdcard/efi/boot/bootia32.efi

Connect to the console output

Connect the serial cable to your computer as shown in [2].

Choose a terminal emulator such as PuTTY. Make sure you use the SCO keyboard mode (on PuTTY that option is at Terminal -> Keyboard, on the left menu). Connect to the appropriate serial port using a baud rate of 115200.

Boot Contiki Image

Turn on your board. After a few seconds you should see the following text in the screen:

Press [Enter] to directly boot.
Press [F7]    to show boot menu options.

Waiting for the system to select the default boot device may be sufficient. However, if this does not boot Contiki or Grub (depending on what is installed as the UEFI boot image) then perform the following procedure after rebooting and waiting for the boot message to appear: Press and select the option "UEFI Misc Device" within the menu.

No additional steps should be required to boot a Contiki UEFI image.

Run the following additional commands to boot a multiboot-compliant image:

$ multiboot /hello-world.galileo
$ boot

Verify that Contiki is Running

This should boot the Contiki image, resulting in the following messages being sent to the serial console:

Starting Contiki
Hello, world

Debugging

This section describes how to debug Contiki via JTAG. The following instructions consider you have the devices: Flyswatter2 and ARM-JTAG-20-10 adapter (see [1]).

Attach the Flyswatter2 to your host computer with an USB cable. Connect the Flyswatter2 and ARM-JTAG-20-10 adapter using the 20-pins head. Connect the ARM-JTAG-20-10 adapter to Galileo Gen2 JTAG port using the 10-pins head.

Once everything is connected, run Contiki as described in "Running" section, but right after loading Contiki image (multiboot command), run the following command:

$ make TARGET=galileo debug

The 'debug' rule will run OpenOCD and gdb with the right parameters. OpenOCD will run in background and its output will be redirected to a log file in the application's path called LOG_OPENOCD. Once gdb client is detached, OpenOCD is terminated.

If you use a gdb front-end, you can define the "GDB" environment variable and your gdb front-end will be used instead of default gdb. For instance, if you want to use cgdb front-end, just run the command:

$ make BOARD=galileo debug GDB=cgdb

References

[1] https://communities.intel.com/message/211778

[2] https://software.intel.com/en-us/articles/intel-galileo-gen-2-board-assembly-using-eclipse-and-intel-xdk-iot-edition

[3] https://www.gnu.org/software/grub/manual/multiboot/multiboot.html

[4] http://www.uefi.org/

[5] https://www.git-scm.com/book/en/v2/Customizing-Git-Git-Configuration

[6] https://docs.docker.com/docker-for-windows/#/shared-drives

[7] https://docs.docker.com/engine/understanding-docker/