Talk:NixOS on ARM/Raspberry Pi 4

I am a bit confused here, it seems like there is a lot of valueable information, but it hard to follow. Can someone help me clear it up, please?

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About which image to use it says:

First follow the generic installation steps to get the installer image and install using the installation and configuration steps. (Link to https://wiki.nixos.org/wiki/NixOS_on_ARM#Installation which itself links to https://hydra.nixos.org/job/nixos/release-20.03/nixos.sd_image.aarch64-linux) Until the generic image works, a temporary device-specific image is build on Hydra. Note that this image is not using u-boot, but rather the Raspberry Pi specific bootloader configuration. (Link to https://hydra.nixos.org/job/nixos/trunk-combined/nixos.sd_image_raspberrypi4.aarch64-linux)

Only the later link gave me an image that would boot on my RP4(4GB)

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There is also this line: "These configurations will boot (from this PR comment):" But then no configurations do follow.

Viable Pi 4 (B) image(s)

(The confusion around working images is compounded by the fact that Hydra offers identically-named downloads have non-identical contents, and the underscore/hyphen nomenclature varies wildly. It took me a while to confirm that the file I'd downloaded matched the build link below.)

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Currently, build #149338044 has worked twice on my Pi 4 (B) hardware. My usage is command-line only (Bash on TTY + ssh/mosh headless use), and the first run was stable for about three or four weeks of daily-ish use.

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To be quite honest, I'm not sure how I found that specific working image.

I know my path led past here, which is why I'm posting, but I know it involved a lot of negotiating with Hydra's willingness to purge long-running queries and finding a way to list successful sd_image_new_kernel.aarch64-linux builds (maybe via this query?. Following that logic has been somewhat of a mixed bag, eg today I've unsuccessfully attempted to get both build #154444353 and build #154444322 to run.

Enabling the SPI

This section is confusing, mostly because it has factual errors and i can't get it to work. For starters, it talks about dtsoFile = ./spi0-0cd.dtso;, which should probably be dtboFile = ./spi0-0cs.dtbo; (note the dtbo and cs part, the page mentions dtso and cd) - at least that is my idea, if i look at the link's (below) target, which is https://github.com/raspberrypi/firmware/blob/master/boot/overlays/spi0-0cs.dtbo

Also, it is unclear on how one should change the compatible field in a dtbo-file - editing is only possible on their corresponding source files - while the text actually mentions dtbo here ;)

I've adapted my configuration to this but don't get any spi devices (nor does spi appear in dmesg). I'm also wondering wether using boot.kernelPackages = pkgs.linuxPackages_rpi4; is still relevant (it is mentioned in nixos-hardware-issues/565) while some other user claims that "using nixos-hardware wasn't necessary anymore" (nixos-hardware/issues/631 - maybe unrelated)

It would probably help, if someone knowledgeable can verify these instructions and in general clarify the confusions i mentioned.

Thanks in advance, Riot (talk) 21:44, 3 April 2024 (UTC)