Added limitations description for the QAT compression PMD.
Updated intermediate buffers description in qat.rst file.
Signed-off-by: Tomasz Jozwiak <tomaszx.jozw...@intel.com>
---
doc/guides/compressdevs/qat_comp.rst | 4 ++++
doc/guides/cryptodevs/qat.rst | 6 ++++--
2 files changed, 8 insertions(+), 2 deletions(-)
diff --git a/doc/guides/compressdevs/qat_comp.rst
b/doc/guides/compressdevs/qat_comp.rst
index 567a1fc..5631cb1 100644
--- a/doc/guides/compressdevs/qat_comp.rst
+++ b/doc/guides/compressdevs/qat_comp.rst
@@ -35,6 +35,10 @@ Limitations
* Compressdev level 0, no compression, is not supported.
* Queue pairs are not thread-safe (that is, within a single queue pair, RX and
TX from different lcores is not supported).
* No BSD support as BSD QAT kernel driver not available.
+* Number of segments in mbuf chains in the op must be <=
RTE_PMD_QAT_COMP_SGL_MAX_SEGMENTS from the config file.
+* When using Deflate dynamic huffman encoding for compression, the input size
(op.src.length)
+ must be < CONFIG_RTE_PMD_QAT_COMP_IM_BUFFER_SIZE from the config file,
+ see :ref:`building_qat_config` for more details.
Installation
diff --git a/doc/guides/cryptodevs/qat.rst b/doc/guides/cryptodevs/qat.rst
index 9fb9f01..d692c17 100644
--- a/doc/guides/cryptodevs/qat.rst
+++ b/doc/guides/cryptodevs/qat.rst
@@ -145,6 +145,8 @@ Quick instructions for QAT compressdev PMD are as follows:
make
+.. _building_qat_config:
+
Build Configuration
~~~~~~~~~~~~~~~~~~~
@@ -180,8 +182,8 @@ An extra (max_inflight_ops x 16) bytes per queue_pair will
be used for every inc
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
plus
-1472 bytes are allocated.
+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::
--
2.7.4
