Hi,

I have a fairly ancient laptop with a Broadcom BCM4318 wifi card which I'm using for Linux projects. I've recently built LFS 10 with systemd and it works fine with a wired connection, but I'm struggling with Wifi. I have a working Debian 10 XFCE installation to compare to.

I've attempted to extract the b43 firmware using the b43-fwcutter-019 package and the broadcom-wl-5.100.138 firmware. In /lib/firmware I can see a b43 directory with the expected files when compared to Debian's result after running firmware-b43-installer.

I've installed wpa_supplicant and dhcpcd to manage the connections but the wifi card doesn't seem to be loaded and available. iwconfig lists lo, enp6s8 and sit0 with no wireless extension. lsmod lists nothing. Running gives .

I feel like I've missed out something fundamental but as far as I can see the kernel compilation included the correct wireless settings. Any ideas what to check next?

Thanks,

James

OK I worked it out. I had made a number of errors some of which will seem quite obvious...

It seems I hadn't found the options needed in the make menuconfig stage of configuring the kernel, so I hadn't compiled the kernel properly. Under device drivers -> network device support -> wireless lan were all the listings of the drivers I needed. So I selected the Broadcom 43xx support and the 4 options below for ...-PHY (not sure whether those are needed). NB - I needed to compile the Broadcom 43xx support as a module, i.e. make sure it was selected with an M not a *. Compiling it as a module would mean that the 3rd party firmware needed could be loaded. So I recompiled the kernel and installed the new kernel and modules.

Once I had done this I rebooted and saw that dmesg | grep b43 showed there was some activity with loading the wifi interface. Issuing modprobe b43 brought the wifi device onto the ip link listing. So finally I created a file /etc/modules with the single entry b43.ko in order that the b43 module would load at boot time automatically.

From this point on using wpa-supplicant and DHCP worked fine as per the BLFS manual.

This is actually part of what I wanted to understand better by compiling a system from scratch as I had no idea why my wifi would work easily with some distributions and not others, and sometimes not even some variants of the same distribution! Now I at least know where to look...