PCHB(4)

📦 in nixpkgs unstable

✨ pchb(4) — PCI-Host Bridge ✨

okay so bestie, welcome to the pchb(4) page from the Kernel Interfaces Manual — it’s literally the PCI-Host Bridge, and she’s lowkey doing a lot of behind-the-scenes work 💅

🌸 NAME 🌸

pchb — PCI-Host Bridge

🦋 SYNOPSIS 🦋

pchb* at pci?
pci* at pchb?

💖 DESCRIPTION 💖

The pchb driver provides support for PCI-Host adapter-specific functions. It’s got your back for these devices, no cap:

  • i450 PCIset (Orion) — supports additional PCI buses.
  • Reliance Computer ROSB4, CNB20HE, CNB20LE — supports additional PCI buses.
  • i82424ZX (Saturn) — disables CPU-PCI write posting.
  • i82443BX — provides workaround for the following errata: “An incorrect address may be driven on the DRAM bus, resulting in memory data being fetched from the wrong location.”
  • i82810/810E, i82815/815E, i82820, i82840 — supports the random numbers generator, supplying random bytes from the system’s thermal noise. Driven by periodic checks for available data from the generator, it supplies entropy to the random(4) driver for common usage.

On amd64 and i386 systems, most PCI devices of class Bridge and subclass Bridge Host are supported just as PCI attachment points. A few other system control devices not listed here are supported by pchb.

The macppc port supports several Apple and Motorola bridges. cute 🍓

🌈 SEE ALSO 🌈

⭐ HISTORY ⭐

Random number generator support first appeared in OpenBSD 2.7 — iconic behavior tbh 👑

👑 AUTHORS 👑

Support for true RNG present on i82810 chips was added by Michael Shalayeff <mickey@openbsd.org>. we love a contributor 🫶

💀 BUGS 💀

Real RNG probe should fix the PCI scanning loop so it would find the Firmware Hub (i82802) which actually contains the RNG device and probe it as a real PCI device (i.e., common PCI registers are there). not me reading this and going “bestie, the probe is lost” 😭

signing off with source/version Debian, dated July 16, 2013 — stay slay, bestie 💋🎀

📦 where this page comes from