# Firmware

The C630's firmware splits into two groups, and the split is about licensing,
not difficulty.

## What ships in the image

Qualcomm permits redistribution of these, so Fedora packages them and the build
installs them:

| Package | Files | Enables |
|---|---|---|
| `qcom-firmware` | `qcom/a630_gmu.bin`, `qcom/a630_sqe.fw`, `qcom/sdm845/a630_zap.mbn` | Adreno 630 — accelerated graphics via freedreno |
| `atheros-firmware` | `ath10k/WCN3990/hw1.0/{firmware-5.bin,board-2.bin,wlanmdsp.mbn}` | WiFi and Bluetooth |

So graphics and networking work on a freshly written image with no extra steps.

## What has to come off the Windows partition

The SDM850's DSP and display firmware is signed against per-model keys. Nobody
can redistribute it, and it exists on your machine only inside its Windows
install:

| File | Enables |
|---|---|
| `qcadsp850.mbn` | Audio DSP — speakers, microphone |
| `qccdsp850.mbn` | Compute DSP — sensor hub, so lid switch, accelerometer, auto-rotate |
| `qcdxkmsuc850.mbn` | Display/UEFI secure code |
| `qcdsp1v2850.mbn`, `qcdsp2850.mbn` | Modem DSP stages |
| `ipa_fws.elf` | IPA — needed by the modem path |

They belong under `/lib/firmware/updates/qcom/sdm850/LENOVO/81JL/`.

## Extracting them

The image ships Fedora's `qcom-firmware-extract`. Run it once:

```sh
sudo c630-firmware
sudo reboot
```

That wraps `qcom-firmware-extract` and regenerates the initramfs afterwards,
which matters — the ADSP firmware has to be available before the root
filesystem is mounted, and `overlay/etc/dracut.conf.d/10-c630.conf` only takes
effect on a rebuild.

If it cannot find Windows, mount it yourself and point the tool at it:

```sh
lsblk -o NAME,SIZE,FSTYPE,LABEL       # find the NTFS partition
sudo mkdir -p /mnt/windows
sudo mount /dev/sda4 /mnt/windows
sudo qcom-firmware-extract --windows-dir /mnt/windows
```

`qcom-firmware-extract` was written for the Snapdragon 8cx and X Elite laptops.
If it does not recognise the SDM850, copy the files by hand — they are in
`Windows/System32/DriverStore/FileRepository/` under a `qcdx*.inf_arm64_*`
directory:

```sh
sudo find /mnt/windows/Windows/System32/DriverStore/FileRepository \
    -iname 'qc*850.mbn' -o -iname 'ipa_fws.elf' -o -iname 'qcdxkmsuc850.mbn'

sudo mkdir -p /lib/firmware/updates/qcom/sdm850/LENOVO/81JL
sudo cp <each file> /lib/firmware/updates/qcom/sdm850/LENOVO/81JL/
sudo dracut --force --regenerate-all
```

Check it took:

```sh
dmesg | grep -iE 'remoteproc|adsp|cdsp'
```

## Baking firmware into the image

If you would rather not repeat the extraction on every reinstall, drop the files
into `firmware/local/` in this repo, mirroring the `/usr/lib/firmware/updates/`
layout:

```
firmware/local/qcom/sdm850/LENOVO/81JL/qcadsp850.mbn
firmware/local/qcom/sdm850/LENOVO/81JL/qccdsp850.mbn
...
```

`build/stage2.sh` picks them up automatically. They are gitignored, and should
stay that way — this repository is public and the blobs are not yours to
publish.