This blog post aims to give more explanations and an in-depth process as for how the fuck I managed to make a raspberrypi 3b+ kodi media center capable of smoothly decoding any video codec.

things you'll need

For this, we used the following stack of things:

thinking sand, pieces and cables to get

First of all, as you may have guessed given the very reduced hardware decoding capabilities of any of the rasbperry pi models, we're not going to use it on its own.

Here's the catch: all of the decoding happens in a virtual machine. The rpi is merely a remote display client. As for the VM part, no need for a beefy machine.

I've picked a ThinkCentre mini m710q for the codecs supported by its integrated GPU (the HD 630 packaged with the i3-7100T). Here it is in all its glory:

The raspberrypi I used is the well-known RPI3B+ model, as seen in the intro of this post.

In short, you'll need the following bits for the setup to work correctly:

• a x86 machine supporting virtualization and GVT-g with hardware video decode (for the hypervisor).
• a raspberry pi 3B or B+ (models supported by steamlink)
• a gigabit wired network between the two. it's important the two machines are on the same L2 segment.
• your usual tv set with an hdmi input.
• other bits and bobs: an hdmi cable, a microSD card, a usb key and a linux computer.

cursed code to download

As for the software stack, we're going to use:

• latest Proxmox VE hypervisor on the thinkcentre.
• Raspberry Pi OS ®, The Official Raspberry Foundation™ System (buster armhf version).
• Windows 10 ISO installer for the VM.
• the PC Steam Client.
• Kodi Matrix 19.5 release.
• steamlink software package for the Raspberry Pi OS ®.

the install process

on the hypervisor

First of all, we need to prepare some things on the hypervisor before actually beginning with the install of the VM. Thanks to this great thread on the Proxmox Forum, we've got all the options we need to set in order to enable GVT-g support on the hypervisor !

1. Modify kernel command line, edit GRUB_CMDLINE_DEFAULT in /etc/default/grub so that it reads:

   GRUB_CMDLINE_LINUX_DEFAULT="quiet intel_iommu=on video=vesafb:off video=efifb:off video=simplefb:off modules_load=kvmgt"

2. Modify /etc/modules to load the following kernel modules:

   vfio
   vfio_iommu_type1
   vfio_pci
   vfio_virqfd
   kvmgt

3. edit /etc/modprobe.d/gvtg.conf to ask the i915 kernel module to enable gvt-g:

   options i915 enable_gvt=1

4. run update-grub and update-initramfs -u -k all. Then reboot the hypervisor.

vm install

Now onto the tricky part ! First of all, we start by defining our new VM in Proxmox VE. You should have roughly the same configuration as this one to begin with (the main gotchas are the uefi boot mode, the pc-q35-7.1 machine model and the gvt-g gpu):

By doing this, you should now have access to VM controls with the native noVNC console on the hypervisor. Go on with the windows install, make sure all the video drivers install correctly. CPU-z and GPU-z should show you native cpu and gpu detected:

Then, follow this guide to install TightVNC as a system service on the windows vm. You can now connect directly to the vm with the vnc client of your choice.

Since we have no possibility of using a dummy plug dongle for edid simulation, we have to force the resolution through some good old regedit (see this superuser question):

kodi install

There's not much to say about the Kodi install, we're using the standard x64 installer from the "Matrix" release. I'm not using Nexus (yet!) since I've had some issues regarding smb shares with it.

on the raspberrypi

Good news ! We're now done with the server side of things. Let's get to the "client" now...

system install

Unpack the .img.xz file you previously got and dd it to the microSD card of the raspberry pi. By default, latest OS images come with ssh disabled. In order to be able to connect on first boot, you'll need to create the ssh and the userconf.txt files in the fat32 /boot partition of the system, as explained here and here.

steamlink install

Installing steamlink is as straightforward as what's explained in valve's forum

Just enter

sudo apt update
sudo apt install steamlink
steamlink

and voilà ! the first time is a bit slower since the wrapper will download the latest version of the client first.

You should now be able to connect to the virtual machine we set up earlier (given steam client is up and running). You can now add a shortcut to Kodi in order to have it in the launch menu when connecting:

You're now done ! Grab that popcorn and enjoy the well-deserved movies :)