RTW88(4)

NAME
rtw88 - Realtek IEEE 802.11n/ac wireless network driver

SYNOPSIS
The driver will auto-load without any user interaction using devmatch(8) if enabled in rc.conf(5).

Only if auto-loading is explicitly disabled, place the following lines in rc.conf(5) to manually load the driver as a module at boot time:

    kld_list="${kld_list} if_rtw88"

The driver should automatically load any rtw88fw(4) firmware needed for the particular chipset.

It is discouraged to load the driver from loader(8).

DESCRIPTION
The rtw88 driver is derived from Realtek's Linux rtw88 driver.

The driver uses the linuxkpi_wlan and linuxkpi compat framework to bridge between the Linux and native FreeBSD driver code as well as to the native net80211(4) wireless stack.

HARDWARE
The rtw88 driver supports PCIe devices with the following chipsets:

•   Realtek 802.11n wireless 8723de (RTL8723DE)
•   Realtek 802.11ac wireless 8821ce (RTL8821CE)
•   Realtek 802.11ac wireless 8822be (RTL8822BE)
•   Realtek 802.11ac wireless 8822ce (RTL8822CE)

LOADER TUNABLES

compat.linuxkpi.skb.mem_limit
    If you are running a 64bit system with more than 4GB of main memory you need to set this tunable to 1 in loader.conf(5) and reboot once to make it effective. This tunable will work around a problem with DMA and limit allocations for network buffer memory to the lower 32bit of physical memory and make the driver work.

SEE ALSO
rtw88fw(4), wlan(4), networking(7), fwget(8), ifconfig(8), wpa_supplicant(8)

HISTORY
The rtw88 driver first appeared in FreeBSD 13.2.

BUGS
Certainly.

Does not seem to work (reliably) on machines with more than 4GB of main memory. See in the LOADER TUNABLES section above.

While rtw88 supports 802.11a/b/g/n/ac modes, the compatibility code currently only supports 802.11a/b/g modes. Support for 802.11n/ac is yet to come.