liminix/devices/qemu/default.nix
2023-12-21 19:25:45 +00:00

73 lines
2.2 KiB
Nix

# This "device" generates images that can be used with the QEMU
# emulator. The default output is a directory containing separate
# kernel (uncompressed vmlinux) and initrd (squashfs) images
{
system = {
crossSystem = {
config = "mips-unknown-linux-musl";
gcc = {
abi = "32";
arch = "mips32"; # maybe mips_24kc-
};
};
};
description = ''
QEMU MIPS
*********
This target produces an image for
QEMU, the "generic and open source machine emulator and
virtualizer".
MIPS QEMU emulates a "Malta" board, which was an ATX form factor
evaluation board made by MIPS Technologies, but mostly in Liminix
we use paravirtualized devices (Virtio) instead of emulating
hardware.
Building an image for QEMU results in a :file:`result/` directory
containing ``run.sh`` ``vmlinux``, and ``rootfs`` files. To invoke
the emulator, run ``run.sh``.
The configuration includes two emulated "hardware" ethernet
devices and the kernel :code:`mac80211_hwsim` module to
provide an emulated wlan device. To read more about how
to connect to this network, refer to :ref:`qemu-networking`
in the Development manual.
'';
module = {pkgs, config, lib, lim, ... }: {
imports = [
../../modules/arch/mipseb.nix
../families/qemu.nix
];
kernel = {
config = {
MIPS_MALTA= "y";
CPU_MIPS32_R2= "y";
SERIAL_8250= "y";
SERIAL_8250_CONSOLE= "y";
};
};
hardware =
# from arch/mips/mti-malta/Platform:load-$(CONFIG_MIPS_MALTA) += 0xffffffff80100000
let addr = lim.parseInt "0x80100000";
in {
loadAddress = addr;
entryPoint = addr;
# Unlike the arm qemu targets, we need a static dts when
# running u-boot-using tests, qemu dumpdtb command doesn't
# work for this board. I am not at all sure this dts is
# *correct* but it does at least boot
dts = lib.mkForce {
src = "${config.system.outputs.kernel.modulesupport}/arch/mips/boot/dts/mti/malta.dts";
includes = [
"${config.system.outputs.kernel.modulesupport}/arch/mips/boot/dts/"
];
};
};
};
}