| 24 Mar 2024 |
 darkwater4213 | Awww | 22:01:05 |
| darkwater4213 | Well, what does make things interesting | 22:01:26 |
| 25 Mar 2024 |
|  root joined the room. | 13:49:18 |
 sorear | I have a riscv-specific kernel patch that I want to test in a full OS environment (prior tests have been musl+busybox in an initramfs) and a nixos x86_64 host/build machine.
Is there an easy way to use nix to cross compile (from x86_64-linux to riscv64-linux) a kernel and rootfs suitable for booting NixOS in QEMU? I don't want to manually determine the correct kernel configuration options, and being able to tweak things in userspace would be useful for future tests.
I do not have an encyclopedic knowledge of nixos internals or non-QEMU hardware. | 15:52:37 |
 Pratham Patel | There is one afaik but I can't point you to it since imho, it is better to not deal with this and buy a VF2 instead, since it is quite cheap and unlike a RPi, has an M.2 2280 slot for an NVMe. | 15:54:04 |
| sorear | the last piece of hw I ordered from China in July still hasn't shipped, and even if I reorder it I want to do this project now, not in 2 months | 15:55:16 |
| Pratham Patel | Even India (a country were getting such niche SBCs is close to impossible) has this available for purchase and shipping under 2 days, max. | 15:57:12 |
| sorear | is there a technical reason to gatekeep qemu users from nixos? | 15:57:27 |
| Pratham Patel | Not sure, I just find it easier to not deal with it, that's all 😅 | 15:57:54 |
| sorear | is there anyone who is willing to answer? | 15:59:34 |
| Pratham Patel | Redacted or Malformed Event | 16:00:33 |
| Pratham Patel | sorear: you can try building the sd-image for the VF2 and override the kernel with your source + any additional patches. If I were to do something like what you described, I'd start from here.
https://nixos.wiki/wiki/NixOS_on_RISCV/VisionFive_2
| 16:05:55 |
| sorear | I still cannot make heads from tails of anything flakes-related | 16:06:57 |
| * Pratham Patel will be back with a tested flake.nix that sorear can reproduce | 16:08:43 |
| sorear | can I ask you questions about what any given thing in a flake does? | 16:11:31 |
| Pratham Patel | stumbled across this: https://github.com/NixOS/nixpkgs/pull/125451 | 16:11:32 |
| Pratham Patel | I don't understand it well enough but sure, do ask me! I'll try to answer if I understand :) | 16:12:06 |
| sorear | if you think the directions you just gave me are intelligible, you understand it much better than i do | 16:12:44 |
| Pratham Patel | Do ask then :) | 16:13:39 |
| root | I have a working setup based on this with custom uboot and kernel for real hw, also a working qemu setup for userspace testing | 16:14:56 |
| root | C908 w/ RVV 1.0. Working on new kernel at the moment. | 16:16:53 |
| Pratham Patel | In reply to @sorear:matrix.org
I still cannot make heads from tails of anything flakes-related Okay this might be helpful if you don't understand flakes... Use this to understand how you can cross compile an armv7l sd-image from any host arch, but do it for riscv64. Then, replace sd-image-aarch64.nix with sd-image-riscv64-qemu.nix. | 16:17:07 |
| sorear | In reply to @thefossguy:matrix.org
Okay this might be helpful if you don't understand flakes... Use this to understand how you can cross compile an armv7l sd-image from any host arch, but do it for riscv64. Then, replace sd-image-aarch64.nix with sd-image-riscv64-qemu.nix. this looks very helpful, it was extremely unclear from the nixos manual whether it was possible to override anything in the standard configurations | 16:22:04 |
| sorear | In reply to @root:0x1.st
I have a working setup based on this with custom uboot and kernel for real hw, also a working qemu setup for userspace testing I may ask about this later if any of it is nontrivial for nix-language or nixpkgs reasons | 16:22:50 |
| Pratham Patel | fyi, I may not reply after a few hours since it's 22:00 here; will reply to your questions (if any) in the morning | 16:23:22 |
 Mic92 | Steven Keuchel: Another question. One can download the edk2 firmware from here: https://github.com/sophgo/sophgo-edk2/actions/runs/8262095841 | 18:07:08 |
| Mic92 | Does it matter which device tree file I download that is mentioned here? https://github.com/sophgo/sophgo-edk2 | 18:07:31 |
| Mic92 | I mean what version of mango-milkv-pioneer.dtb I use? | 18:07:42 |
| Mic92 | Does this need to match up with the Linux kernel or is this used by the efi firmware? | 18:08:28 |
 Alex | In reply to @joerg:thalheim.io
Does this need to match up with the Linux kernel or is this used by the efi firmware? The Linux kernel tree has its own DTBs, but IIRC it can use the DTB provided by EFI, so doesn't it depend on what parameters you're passing the kernel? | 20:26:04 |
