QAT_C2XXX(4)

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

💅 QAT_C2XXX — the Intel QuickAssist driver for Atom C2000 chipsets, bestie edition 💖

okay so this page is from the Kernel Interfaces Manual section, and it's literally all about qat_c2xxx — the Intel QuickAssist Technology (QAT) driver for Atom C2000 chipsets. it's giving "niche but iconic" ngl 🌸

✨ SYNOPSIS ✨

so if you wanna compile this driver into the kernel (main character move, no module loading shenanigans), you drop these lines into your kernel configuration file:

device crypto
device cryptodev
device qat

or — and this is lowkey the easier vibe — you can load it as a module at boot time by putting these lines in loader.conf(5):

qat_c2xxx_load="YES"
qat_c2xxxfw_load="YES"

that's it. two lines. slay 🎀

🦋 DESCRIPTION 🦋

the qat_c2xxx driver implements crypto(4) support for some of the cryptographic acceleration functions of the Intel QuickAssist (QAT) device found on Atom C2000 devices. not all of them. some. we're being honest here 💅

QAT devices are enumerated through PCIe, which means you can literally see them in pciconf(8) output — go look, they're there, iconic 👑

and here's what this driver can actually do — it can accelerate AES in CBC, CTR, and GCM modes, and can perform authenticated encryption combining the CBC and CTR modes with SHA1-HMAC and SHA2-HMAC. it can also compute SHA1 and SHA2 digests. ate and left no crumbs 🔥

⚠️ but bestie, listen — the AES-GCM implementation has a firmware-imposed constraint: the length of any additional authenticated data (AAD) must not exceed 240 bytes. the driver thus rejects crypto(9) requests that don't satisfy this constraint. so keep your AAD short or it's not happening, fr fr 😭

🌈 SEE ALSO 🌈

the whole friend group:

iykyk go read them 🫶

⭐ HISTORY ⭐

the qat_c2xxx driver first appeared in FreeBSD 13.0. a whole era 💜

👑 AUTHORS 👑

  • the qat_c2xxx driver was written for NetBSD by Hikaru Abe <hikaru@iij.ad.jp>
  • Mark Johnston <markj@FreeBSD.org> ported the driver to FreeBSD

two legends, one driver, we love to see it 🫶✨

💀 BUGS 💀

okay so this is the part where we're real with each other. some Atom C2000 QAT devices have two acceleration engines instead of one. the qat_c2xxx driver currently misbehaves when both are enabled — and thus does not enable the second acceleration engine if one is present. so like… one engine it is. not me pretending that's fine 🙈 it's a known thing, not a vibe, just a fact.

and that's the whole page, bestie — go forth and accelerate your crypto 💖

sign-off szn: this gem was rendered by Debian, dated July 21, 2022, and it's a page from the Kernel Interfaces Manual. mwah, catch you on the next manpage 😘🎀

📦 where this page comes from