Iwlwifi

iwlwifi is the wireless driver for Intel's current wireless chips.

Kernel
To make it work some kernel configuration is needed. The driver supports 802.11a/b/g/n/ac (depending on the device), so IEEE 802.11 should be enabled.

Device driver iwlwifi
Set it as a module  as shown here. Do not forget the DVM /MVM options. After changes on kernel configuration do not forget to rebuild the kernel.

Firmware
Also firmware for the individual device is needed as listed in this table. It is available in and in device-specific sys-firmware/iwlxxxx-*ucode packages.

Alternative setup
In case the driver is built into the kernel instead as a module, also the firmware needs to be built into the kernel.

In this case replace  with the exact firmware name. Some attention seems to be needed for FW_LOADER_USER_HELPER_FALLBACK.

Common pitfalls

 * FW_LOADER_USER_HELPER_FALLBACK