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Michael LeMay 3908253038 x86: Add support for (paging-based) protection domains

This patch implements a simple, lightweight form of protection domains
using a pluggable framework.  Currently, the following plugin is
available:

 - Flat memory model with paging.

The overall goal of a protection domain implementation within this
framework is to define a set of resources that should be accessible to
each protection domain and to prevent that protection domain from
accessing other resources.  The details of each implementation of
protection domains may differ substantially, but they should all be
guided by the principle of least privilege.  However, that idealized
principle is balanced against the practical objectives of limiting the
number of relatively time-consuming context switches and minimizing
changes to existing code.

For additional information, please refer to cpu/x86/mm/README.md.

This patch also causes the C compiler to be used as the default linker
and assembler.

2016-03-21 17:18:06 -07:00

6.5 KiB

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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
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.

Building

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.

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

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

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.

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

Approach for UEFI Image

Copy Contiki binary image to sdcard

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

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.

Press and select the option "UEFI Internal Shell" within the menu.

Boot Multiboot-compliant ELF Image

Once you have a shell, run the following commands to run grub application:

$ fs0:
$ grub.efi

You'll reach the grub shell. Now run the following commands to boot Contiki image:

$ multiboot /hello-world.galileo
$ boot

Boot UEFI Image

Once you have a shell, run the following commands to boot Contiki image:

$ fs0:
$ hello-world.galileo.efi

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: