+.. code-block:: console
+
+ cd to the top-level DPDK directory
+ make defconfig
+ make
+
+
+.. _building_qat_config:
+
+Build Configuration
+~~~~~~~~~~~~~~~~~~~
+
+These are the build configuration options affecting QAT, and their default values:
+
+.. code-block:: console
+
+ CONFIG_RTE_LIBRTE_PMD_QAT=y
+ CONFIG_RTE_LIBRTE_PMD_QAT_SYM=n
+ CONFIG_RTE_LIBRTE_PMD_QAT_ASYM=n
+ CONFIG_RTE_PMD_QAT_MAX_PCI_DEVICES=48
+ CONFIG_RTE_PMD_QAT_COMP_IM_BUFFER_SIZE=65536
+
+CONFIG_RTE_LIBRTE_PMD_QAT must be enabled for any QAT PMD to be built.
+
+Both QAT SYM PMD and QAT ASYM PMD have an external dependency on libcrypto, so are not
+built by default. CONFIG_RTE_LIBRTE_PMD_QAT_SYM/ASYM should be enabled to build them.
+
+The QAT compressdev PMD has no external dependencies, so needs no configuration
+options and is built by default.
+
+The number of VFs per PF varies - see table below. If multiple QAT packages are
+installed on a platform then CONFIG_RTE_PMD_QAT_MAX_PCI_DEVICES should be
+adjusted to the number of VFs which the QAT common code will need to handle.
+
+.. Note::
+
+ There are separate config items (not QAT-specific) for max cryptodevs
+ CONFIG_RTE_CRYPTO_MAX_DEVS and max compressdevs CONFIG_RTE_COMPRESS_MAX_DEVS,
+ if necessary these should be adjusted to handle the total of QAT and other
+ devices which the process will use. In particular for crypto, where each
+ QAT VF may expose two crypto devices, sym and asym, it may happen that the
+ number of devices will be bigger than MAX_DEVS and the process will show an error
+ during PMD initialisation. To avoid this problem CONFIG_RTE_CRYPTO_MAX_DEVS may be
+ increased or -w, pci-whitelist domain:bus:devid:func option may be used.
+
+
+QAT compression PMD needs intermediate buffers to support Deflate compression
+with Dynamic Huffman encoding. CONFIG_RTE_PMD_QAT_COMP_IM_BUFFER_SIZE
+specifies the size of a single buffer, the PMD will allocate a multiple of these,
+plus some extra space for associated meta-data. For GEN2 devices, 20 buffers are
+allocated while for GEN1 devices, 12 buffers are allocated, plus 1472 bytes overhead.
+
+.. Note::
+
+ If the compressed output of a Deflate operation using Dynamic Huffman
+ Encoding is too big to fit in an intermediate buffer, then the
+ operation will fall back to fixed compression rather than failing the operation.
+ To avoid this less performant case, applications should configure
+ the intermediate buffer size to be larger than the expected input data size
+ (compressed output size is usually unknown, so the only option is to make
+ larger than the input size).
+
+
+Device and driver naming
+~~~~~~~~~~~~~~~~~~~~~~~~
+
+* The qat cryptodev symmetric crypto driver name is "crypto_qat".
+* The qat cryptodev asymmetric crypto driver name is "crypto_qat_asym".
+
+The "rte_cryptodev_devices_get()" returns the devices exposed by either of these drivers.
+
+* Each qat sym crypto device has a unique name, in format
+ "<pci bdf>_<service>", e.g. "0000:41:01.0_qat_sym".
+* Each qat asym crypto device has a unique name, in format
+ "<pci bdf>_<service>", e.g. "0000:41:01.0_qat_asym".
+ This name can be passed to "rte_cryptodev_get_dev_id()" to get the device_id.
+
+.. Note::
+
+ The cryptodev driver name is passed to the dpdk-test-crypto-perf tool in the "-devtype" parameter.
+
+ The qat crypto device name is in the format of the slave parameter passed to the crypto scheduler.
+
+* The qat compressdev driver name is "compress_qat".
+ The rte_compressdev_devices_get() returns the devices exposed by this driver.
+
+* Each qat compression device has a unique name, in format
+ <pci bdf>_<service>, e.g. "0000:41:01.0_qat_comp".
+ This name can be passed to rte_compressdev_get_dev_id() to get the device_id.