Building and Managing Power Analysis Driver

Configuring the Basic Software Environment

To compile the power analysis driver, the target system must have the following software installed:

• C compiler that was used to build the kernel and that is capable of compiling programs with anonymous structs/unions, for example, GCC* 2.96 or later.

• Tools needed to build a C-based program, for example, GNU* make tool, native assembler, linker.

• System headers, for example, /usr/include/.

In addition, the kernel version must be 2.6.32 or later and must be configured with the following options enabled:

• CONFIG_MODULES=y
• CONFIG_MODULE_UNLOAD=y
• CONFIG_TRACEPOINTS=y
• CONFIG_FRAME_POINTER=y
• CONFIG_COMPAT=y
• CONFIG_TIMER_STATS=y

Configuring the Kernel Development Environment

• Linux distributions based on kernel 2.6 * Red Hat Enterprise* Linux 6: Install the kernel-*-devel-*.rpm that is appropriate for the running kernel (on the third install CD)

• Red Hat Fedora* Core 12 and later: Download and install the kernel-*-devel-*.rpm that is appropriate for the running kernel from http://download.fedora.redhat.com/pub/fedora/linux/ or by using YUM:

  $ yum install kernel-devel

• Novell* SuSE Linux Enterprise Server* 10, 11 and Novell OpenSuSE*11.x: Install the kernel-source-*-`uname -m`.rpm that is appropriate for the running kernel

• Red Flag* 5.x: Install the kernel-*-devel-*.rpm that is appropriate for the running kernel (on second install CD)

• Debian* 5.x and Ubuntu* 10.x: Install the GCC and kernel development environment via:

  $ apt-get update

  $ apt-get install build-essential

  $ apt-get install linux-headers-`uname -r` 4

For kernels or Linux distributions not mentioned above, you need to set up the kernel build environment manually. This involves configuring the kernel sources (and hence kernel headers) to match the running kernel on the target system. For 2.6-based kernels, the kernel sources can be configured as follows:

# boot into the kernel you wish to build driver for
# and make sure the kernel source tree is placed in
#/usr/src/linux-`uname -r`
#
cd /usr/src/linux-`uname -r`
vi Makefile # set EXTRAVERSION to a value corresponding to `uname -r`
make mrproper
cp /boot/config-`uname -r` .config
make oldconfig
make prepare
make scripts

Once the configuration completes, make sure that UTS_RELEASE in /usr/src/linux-`uname -r`/include/linux/version.h or in /usr/src/linux-`uname -r`/include/linux/utsrelease.h matches `uname -r`.

Building and (Re)Loading the Driver

Once the standard development tools and proper kernel development environment are installed, you can build and load the driver:

# build the driver:
cd /path/to/powerdk/src/
./build-driver

# unload previously loaded driver from the kernel (if any):
cd /path/to/powerdk/src/
./rmmod-apwr2

# load the driver into the kernel:
cd /path/to/powerdk/src/
sudo ./insmod-apwr2

# autoload the driver at boot time:
cd /path/to/powerdk/src/
./boot-script -g users -d /path/to/pre-built-drivers

If any errors occur during the building or loading of the driver, this may indicate a mismatch between the kernel sources and the running kernel. For load issues, check the /var/log/messages file or the output of dmesg.