---
name: "qat"
section: "4"
platform: "freebsd"
package: "base"
version: "16.0-CURRENT-20261027-61c70dc16a79"
release: "FreeBSD 16.0-CURRENT (2026-10-27)"
platforms: ["freebsd"]
url: "https://new.carta.tech/qat"
---

# qat(4)

Intel QuickAssist Technology compression and crypto driver

## NAME

**qat** – Intel QuickAssist Technology compression and crypto driver

## SYNOPSIS

To load the driver call:

-

  kldload qat

In order to load the driver on boot add these lines to [loader.conf(5)](/loader.conf/5.md) selecting firmware(s) suitable for installed device(s)

-

  qat\_200xx\_fw\_load="YES"

-

  qat\_c3xxx\_fw\_load="YES"

-

  qat\_c4xxx\_fw\_load="YES"

-

  qat\_c62x\_fw\_load="YES"

-

  qat\_dh895xcc\_fw\_load="YES"

-

  qat\_4xxx\_fw\_load="YES"

-

  qat\_load="YES"

## DESCRIPTION

The **qat** driver supports cryptography and compression acceleration of the Intel (R) QuickAssist Technology (QAT) devices.

A complete API for offloading these operations is exposed in the kernel and may be used by any other entity directly. In addition to exposing a complete kernel API for offloading cryptography and compression operations, the **qat** driver also integrates with [crypto(4)](/crypto/4.md), allowing offloading supported operations to Intel QuickAssist Technology devices.

## HARDWARE

The **qat** driver supports the following Intel QuickAssist Technology Engines:

- Intel (R) C62x Chipset

- Intel (R) Atom C3000 processor product family

- Intel (R) QuickAssist Adapter 8960/Intel (R) QuickAssist Adapter 8970 (formerly known as "Lewis Hill")

- Intel (R) Communications Chipset 8925 to 8955 Series

- Intel (R) Atom P5300 processor product family

- Intel (R) QAT 4xxx Series

## SYSCTL VARIABLES

The following [sysctl(8)](/sysctl/8.md) variables may be used to reconfigure the **qat** device. For configuration persistence those variables may be set before loading the driver, either via [kenv(1)](/kenv/1.md) or [loader.conf(5)](/loader.conf/5.md).

The specific device needs to be in the "down" state before changing the configuration.

- *dev.qat.X.state*

  Show or set current state of the device. Possible values: "down", "up".

  NOTE: If the symmetric services are used for device the **qat\_ocf** driver needs to be disabled prior the device reconfiguration.

- *dev.qat\_ocf.0.enable*

  Enable/disable the QAT cryptographic framework connectivity. Enabled by default.

- *dev.qat.X.cfg\_services*

  Override the device services enabled, may be one of: symmetric, asymmetric, data compression. Possible values: "sym", "asym", "dc", "sym;dc", "asym;dc", "sym;asym". Default services configured are "sym;asym" for even and "dc" for odd devices.

- *dev.qat.X.cfg\_mode*

  Override the device mode configuration for kernel space and user space instances. Possible values: "ks", "us", "ks;us". Default value "ks;us".

- *dev.qat.X.num\_user\_processes*

  Override the number of uio user space processes that can connect to the QAT device. Default: 2

- *dev.qat.X.disable\_safe\_dc\_mode*

  Override history buffer mitigation. Disabled by default. If enabled, decompression throughput increases but may result in a data leak if *dev.qat.X.num\_user\_processes* is more than 1. Enable this option only if your system is not prone to user data leaks.

The following [sysctl(8)](/sysctl/8.md) variables are read-only:

- *dev.qat.X.frequency*

  QAT device frequency value.

- *dev.qat.X.mmp\_version*

  QAT MMP Library revision number.

- *dev.qat.X.hw\_version*

  QAT hardware revision number.

- *dev.qat.X.fw\_version*

  QAT firmware revision number.

- *dev.qat.X.dev\_cfg*

  Summary of device specific configuration.

- *dev.qat.X.heartbeat*

  QAT device heartbeat status. Value '1' indicates that the device is operational. Value '0' means that the device is not responsive. Device requires restart.

- *dev.qat.X.heartbeat\_failed*

  Number of QAT heartbeat failures received.

- *dev.qat.X.heartbeat\_sent*

  Number of QAT heartbeat requests sent.

## SEE ALSO

[crypto(4)](/crypto/4.md), [ipsec(4)](/ipsec/4.md), [pci(4)](/pci/4.md), [crypto(7)](/crypto/7.md), [crypto(9)](/crypto/9.md)

For details of usage and supported operations and algorithms refer to the following documentation available from Intel Download Center **https://downloadcenter.intel.com**:

- Intel (R), *QuickAssist Technology API Programmer's Guide*.

- Intel (R), *QuickAssist Technology Cryptographic API Reference Manual*.

- Intel (R), *QuickAssist Technology Data Compression API Reference Manual*.

- Intel (R), *QuickAssist Technology Performance Optimization Guide*.

## HISTORY

A **qat** driver appeared in FreeBSD 13.0. It was superseded in FreeBSD 14.0 by the upstream driver.

## AUTHORS

The **qat** driver was written by Intel (R) Corporation.