Akida PCIe driver

Installing driver

Prerequisite: having gcc & build tools available, and kernel headers available

On Ubuntu:

sudo apt install build-essential linux-headers-$(uname -r)

Then simply run the install script from current directory.

./install.sh

It will build the driver, remove old installed driver versions if any, and load the new one. It will also configure modules to load it at every boot, and give read/write access on /dev/akida* to every user.

If you want to control permissions, edit the udev rules with your own preferences in 99-akida-pcie.rules

If you don't want the driver to load on every boot, edit the /etc/modules file after installation and remove akida_pcie line.

After a kernel update you need to run the install script again.

Enable CMA in the kernel

Some systems, e.g.: Ubuntu on x86_64, do not come with CMA (contiguous memory allocation) support enabled in the kernel. This is required to use AKD1500 devices through PCIe if you want to use larger amounts of memory to program big models or make full usage of the pipeline. To build the kernel packages that include such support you can run the dedicated script, tailored for the Ubuntu distribution:

./build_kernel_w_cma.sh

Note: this command might take long time because parallel build is not set by default. To enable that you can export this environment variable before launching the build to use a number of jobs equivalent to the number of available cores:

export MAKEFLAGS="-j $(nproc)"

The script will create the packages and explain how to install and boot on the new kernel.

If you want to go back to an old kernel that does not contain the CMA feature, you can grep the installed kernels that were configured in grub:

grep 'menuentry \|submenu ' /boot/grub/grub.cfg | cut -f2 -d "'"

And then modify the /etc/default/grub file from: GRUB_DEFAULT=0 to: GRUB_DEFAULT=2 if you want the third kernel choice in the obtained list, etc.

Source: https://unix.stackexchange.com/questions/432393/downgrade-linux-kernel-without-grub

Support

Please visit:

• https://doc.brainchipinc.com/ for akida documentation, examples and tutorials
• https://brainchipinc.com/support/ for support requests