This patch adds support for building release images. The main difference between release images and default images is that the former is optimized for size while the latter is "optimized" for debugging. To build a release image, the BUILD_RELEASE variable should be set to 1. For instance, the following command build a release image from the hello-world application: $ cd examples/hello-world && make TARGET=galileo BUILD_RELEASE=1 To optimize for size we use the '-Os' option from gcc. This option also enables the strict aliasing optimization. This generates lots of warning messages since we use the '-Wall' option and lots of code in core/net/ break the strict-aliasing rules. Some test have shown that the strict aliasing optimization it not taking effect in the final binary. For that reasons, this patch manually disables the optimization. Also, the release image is stripped. For the sake of comparison, below follows the output from 'wc' and 'size' for both debugging (default) and release images. Default image: $ wc -c hello-world.galileo 71112 hello-world.galileo $ size hello-world.galileo text data bss dec hex filename 20379 1188 12808 34375 8647 hello-world.galileo Release image: $ wc -c hello-world.galileo 26320 hello-world.galileo $ size hello-world.galileo text data bss dec hex filename 18146 1156 12808 32110 7d6e hello-world.galileo
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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
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)
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. To build applications for Galileo platform you should set 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
- This will generate a Contiki stripped-image optimized for size.
$ cd examples/hello-world/ && make TARGET=galileo BUILD_RELEASE=1
Running
In order to boot the Contiki image, you will need a multiboot-compliant bootloader. 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
Mount the sdcard in directory /mnt/sdcard.
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
Connect to the console output
Connect the serial cable to your computer as showed in [2].
Choose one terminal emulator such as screen, putty or minicom. Make sure you use keyboard SCO mode (on putty that option is at Terminal -> Keyboard, on the left menu). Connect to /dev/ttyUSB0, use 115200 speed.
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.
Press and select the option "UEFI Internal Shell" within the menu. Once you have a shell, run the following commands to run grub application:
$ fs0:
$ grub.efi
You'll reach de grub shell. Now run the following commands to boot Contiki image:
$ multiboot /hello-world.galileo
$ boot
For now, we lack of UART support so you won't see any output. However, you can use JTAG (see next section) to verify that the Contiki is running.
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] http://www.intel.com/support/galileo/sb/CS-035124.htm
[3] https://www.gnu.org/software/grub/manual/multiboot/multiboot.html