Possible missing firmware for module ...

If you got that annoying messages in your arch Linux, I have good news for you, you could get ride off that warnings by installing an Aur package https://aur.archlinux.org/packages/mkinitcpio-firmware with this Aur package you will install the missing firmware required from your kernel.

I installed it with no helpers simply by clonning the repo with:

git clone https://aur.archlinux.org/packages/mkinitcpio-firmware.git

And installing it with his dependencies with:

cd mkinitcpio-firmware
makepkg -si

In case there are missing dependencies you should search for them in Aur repository and install it.