Can I put Debian on my Raspberry Pi?

Yes. To quickly get a ready-to-use image, visit RaspberryPiImages. To know more, please read on.

Booting via a binary blob

All Raspberry Pi models before the 4 (1A, 1B, 1A+, 1B+, Zero, Zero W, 2, 3, Zero 2 W) boot from their GPU (not from the CPU!), so they require a non-free binary blob to boot. This binary blob is available in the non-free Debian repository, packaged as the raspi-firmware package (or raspi3-firmware until Debian 10).

Raspberry Pi OS (formerly Raspbian) and Debian

The most often used distribution across all raspberries is Raspberry Pi OS (originally known as Raspbian), a derivative of Debian. This is, first of all, for historical reasons (booting a mainline Linux kernel was not supported on Raspberries until late 2018), but also because of other non-free components that are shipped as part of Raspberry Pi OS (such as Oracle Java, Wolfram Mathematica, and several games such as a Pi-specific Minecraft version).

Raspberry Pi OS builds a single image for all of the Raspberry families, so you will get an armhf 32-bit, hard floating-point system, but built for the ARMv6 ISA (with VFP2), unlike Debian's ARMv7 ISA (with VFP3) port.

Raspberry Pi OS is not affiliated with the Debian project, although it derives from it. You can also run regular Debian on your Raspberry Pi's! (keep reading...)

Raspberry Pi Models

Raspberry Pi 4 and Raspberry Pi 400

Announced in 2019, this system adds a second HDMI port, more memory, true Gigabit Ethernet and USB3. RPi4 SD card images are available for Debian Bullseye and later.

More technical details about Raspberry Pi 4 support are available on the RaspberryPi4 page.

Raspberry Pi 400

The Raspberry Pi 400, announced in November 2020, is quite similar to the Raspberry Pi 4 B models. RPi 4 images work on the Pi 400, although a different DTB (not yet available/mainlined as of Linux 5.10) is needed for some hardware support, i.e. for WiFi connectivity.

Raspberry Pi 3 (3, 3A+, 3B+, Zero 2 W)

The Raspberry Pi 3 was announced in 2016, and is the first 64-bit member of the family. Some models include wireless connectivity. This family works with Debian arm64. For further details and information on how to run with this hardware, go to the RaspberryPi3 page.

Raspberry Pi 2

The second generation systems were announced on 2014. The only member of this family is the Raspberry Pi 2.

Second-generation Raspberry Pi systems (model 2 only) works with Debian armhf.

You can refer to the RaspberryPi2 page, which aims to collect more detailed information how to run Debian on this hardware.

Raspberry Pi 1 (A, B, A+, B+, Zero, Zero W)

The systems now known as Raspberry Pi model 1 models A and B were announced in February 2012. This family was expanded by very similar models A+ and B+. In 2015, the Zero model was announced, using the same CPU as the 1 family but with a smaller form factor, followed by the Zero W, which adds wireless connectivity.

The first generation Raspberry Pi systems works using Debian armel. The Raspberry Pi 1's processor falls uncomfortably between the processor families that Debian has chosen to target, between armel and armhf. While Raspberry Pi OS solves this to some degree an unofficial port will always give less certainty than an official one.

The Zero uses the same SoC/CPU as the first version, so they should function identically.

Should I buy a Raspberry Pi?

That is a decision that you will have to make given your application, below are some pros and cons that you should consider.

Pros:

Cons:

Other issues:

A number of similar boards are available, generally at slightly higher prices but also usually with more powerful processors. Some examples can be found in the CheapServerBoxHardware list.

Binary blob needed to boot

The binary blob needed to boot the Raspberry Pi has been packaged as raspi-firmware in the non-free repository since Debian Bullseye (In Debian Buster, the Raspberry Pi firmware package is called raspi3-firmware). It can be used with vmdebootstrap to create a bootable SD card image, according to a recipe from Petter Reinholdtsen.

Previously this page referred to rpi-update but that tool is meant for firmware development, not for end users! Therefor that information has been removed.

There is an independent documentation project based on a combination of static analysis and trial and error on real hardware available on https://github.com/hermanhermitage/videocoreiv/, but this has not seen any progress since early 2019 (2021-06).

Since then, Broadcom publicly released some code, licensed as 3-Clause BSD, to aid the making of an open source GPU driver. The "rpi-open-firmware" effort to replace the VPU firmware blob started in 2016. See more at https://news.ycombinator.com/item?id=11703842 . Unfortunately development of rpi-open-firmware is currently (2021-06) stalled.

A revival attempt seems to be underway (2021-06).

QEMU User Emulation for Raspberry Pi Development

See RaspberryPi/qemu-user-static for information on how you can mount, edit, and run a Raspberry Pi disk image on a host Debian machine using QemuUserEmulation (much faster/simpler than than full system emulation)

Giving more power to the USB devices

(Editor's Note: If this is as Raspberry Pi 2 specific as it sounds, it should be movd to RaspberryPi2. I guess that the Raspberry Pi 4's USB3 ports can output more Amps in their default configuration?)

If you are running a lot of devices, you may need a lot of power. Actually, the Pi 2 can give up to 1.2A to the devices, but it is severely limited by default to 600mA, so if you connect a lot of devices, they are going to be reseting themselves or limiting in some ways because of lack of energy. There is an option to actually double the amount of energy you can give to the devices, but you must also use a good 2A adapter. Just edit /boot/config.txt and add this:

max_usb_current=1
safe_mode_gpio=4

This way I am able to run a very energy consuming 4G modem and a Wifi dongle at the same time without issues.

Also, you not only need a good and reliable adapter, but also a good cable. The shorter and thicker the better.