BCMA(4)

📦 version 15.1, in freebsd 14.5, freebsd 15.1, nixpkgs unstable

💖 BCMA(4) 💖

ok so bestie, you're reading the BCMA(4) page from the Kernel Interfaces Manual and honestly? it's giving hardware lore. sit down, grab a strawberry 🍓, let's get into it.

🌸 NAME 🌸

bcma — the Broadcom AMBA Backplane driver. that's it, that's the name, she's iconic and she knows it 💅

✨ SYNOPSIS ✨

so there's two whole ways to get her in your life, pick your fighter:

1. Compile her into the kernel — add these exact lines to your kernel configuration file:

device bhnd
device bcma

2. Load her as a module at boot — drop this line into loader.conf(5):

bcma_load="YES"

no cap, that's the whole vibe. 🫶

🦋 DESCRIPTION 🦋

okay so what does bcma actually do? she provides bhnd(4) support for devices that use the ARM AMBA-based backplane architecture — the kind hanging out in later Broadcom Home Networking Division's network chipsets and embedded systems. yes, that's a mouthful. yes, she ate. 🔥

here's the mental picture: a common interconnect connects all of the backplane's functional blocks together. one big group chat, everyone connected. 💬

those functional blocks? they're called cores. love that for them. and they use the ARM AMBA AXI or APB interface to talk to the devices attached to that interconnect. iykyk.

and here's the cute little family detail: the IP cores used in siba(4) devices were adapted by Broadcom for compatibility with the new interconnect. so like, she's related to siba(4) but she got a glow-up. 💅✨

🔍 SEE ALSO 🔍

go read these too, they're all besties:

👑 HISTORY 👑

the bcma device driver first appeared in FreeBSD 11.0. a legend was born. 🎀

🌈 AUTHORS 🌈

the bcma driver was written by Landon Fuller <landonf@FreeBSD.org>. absolute main character energy, we stan. 🫶👑

and that's the whole page!! this lil gem came from the Debian edition of the manual, dated June 3, 2016, filed under BCMA(4) — mwah, bye bestie! 💖🎀🦋

📦 where this page comes from