1. Verify Hardware Detection
First, confirm that FreeBSD detects your RTL8821CE card. Run the following command in a terminal:
pciconf -lv | grep -A4 network
Look for an entry mentioning "Realtek" and "RTL8821CE" (device ID 0xc821). If it’s listed as a network controller but not yet functional, it’s recognized but needs the driver and firmware loaded.
2. Check for the rtw88 Driver
The rtw88 driver, which supports the RTL8821CE, is included in FreeBSD’s kernel as of version 13.1 and later. To see if it’s available, check for the kernel module:
ls /boot/kernel | grep if_rtw88.ko
If the file exists, the driver is part of your system. If not, you may need to update your FreeBSD installation to a version that includes it (e.g., 14.0 or higher).
3. Install the Firmware
The rtw88 driver requires firmware to operate the RTL8821CE. FreeBSD provides this through the wifi-firmware-rtw88-kmod package. Install it with:
sudo pkg install wifi-firmware-rtw88-kmod
This package includes firmware files like rtw88/rtw8821c_fw.bin, which is specific to the RTL8821CE chipset. After installation, the firmware files will be placed in /boot/modules.
4. Load the Driver and Firmware
Load the rtw88 driver manually to test it:
If your system has more than 4GB of RAM (common on modern machines), you’ll also need to set a loader tunable to ensure proper memory allocation for the driver. Edit /boot/loader.conf (create it if it doesn’t exist) and add:
compat.linuxkpi.skb.mem_limit="1"
Then reboot your system to apply this change:
After rebooting, the driver should autoload via devmatch (enabled by default in /etc/rc.conf). To confirm it’s loaded, run:
You should see if_rtw88.ko listed.
5. Configure the WiFi Interface
Once the driver and firmware are loaded, a WiFi interface (e.g., rtw880) should appear. Check with:
If you see an interface like rtw880, create a WLAN interface:
sudo ifconfig wlan0 create wlandev rtw880
Connect to your WiFi network by editing /etc/wpa_supplicant.conf with your network details:
network={
ssid="YourNetworkName"
psk="YourPassword"
}
Then bring up the interface:
sudo ifconfig wlan0 up
sudo wpa_supplicant -i wlan0 -c /etc/wpa_supplicant.conf &
Obtain an IP address via DHCP:
6. Automate at Boot
To make this persistent, add the following to /etc/rc.conf:
wlans_rtw880="wlan0"
ifconfig_wlan0="WPA DHCP"
This ensures the interface is created and configured automatically on boot.
7. Troubleshooting
Driver Not Loading: If kldload if_rtw88 fails, ensure the firmware is installed and the module is present in /boot/kernel.
No Firmware Errors: Check dmesg for messages like "failed to load rtw88/rtw8821c_fw.bin". Reinstall the firmware package if needed.
Performance Issues: The rtw88 driver is still under development and may not be fully stable. If you encounter stalls or disconnects, try setting these sysctls:
sudo sysctl compat.linuxkpi.rtw88_pci_disable_aspm=1
sudo sysctl compat.linuxkpi.rtw88_disable_lps_deep=1
These disable power-saving features that can cause issues.
Notes
The rtw88 driver supports RTL8821CE, but it’s not perfect yet. Some users report intermittent connectivity, especially on systems with more than 4GB of RAM, hence the mem_limit tunable.
If this doesn’t work, consider the wifibox project, which runs a Linux WiFi driver in a virtualized environment on FreeBSD. It supports RTL8821CE but requires more setup (see GitHub: pgj/freebsd-wifibox-alpine).
This should get your RTL8821CE working on FreeBSD with the right settings and firmware! Let me know if you hit any snags.
