[PATCH] doc: update device configuration in qat guide

[Emma Finn <emma.finn@intel.com>]

Added note for QAT driver information and device
configuration for services.

Signed-off-by: Emma Finn <emma.finn@intel.com>
---
 doc/guides/cryptodevs/qat.rst | 23 ++++++++++++++++++++++-
 1 file changed, 22 insertions(+), 1 deletion(-)

diff --git a/doc/guides/cryptodevs/qat.rst b/doc/guides/cryptodevs/qat.rst
index 68d792e4cc..b56203eed6 100644
--- a/doc/guides/cryptodevs/qat.rst
+++ b/doc/guides/cryptodevs/qat.rst
@@ -499,7 +499,28 @@ If you are running on a kernel which includes a driver for your device, see
 
    The asymmetric service is not supported by DPDK QAT PMD for the Gen 3 platform.
    The actual crypto services enabled on the system depend
-   on QAT driver capabilities and hardware slice configuration.
+   on QAT driver capabilities and hardware slice configuration.\
+
+..note::
+
+   With the introduction of QAT Generation 4, the in-tree drivers are available within the
+   mainline Linux kernel. Out-of-tree (OOT) drivers for QAT Gen 4 are currently in sustaining
+   mode, meaning they will only receive maintenance updates without new feature development.
+   Future generations of QAT will be supported with in-tree drivers exclusively.
+
+.. note::
+
+   For **in-tree drivers**, when multiple QAT instances are available, each instance is assigned a
+   different crypto service by default (asym;sym or dc). The available crypto queue pair request
+   will return zero if the corresponding service is not enabled.
+
+   To verify the device configuration, run:
+    cat /sys/bus/pci/devices/<BDF>/qat/cfg_services
+
+   For symmetric and asymmetric crypto services, ensure that `"asym;sym"` are enabled.
+   For **out-of-tree drivers**, the configuration file for each instance can be found at:
+    /etc/<GEN>_dev<ID>.conf
+
 
 Installation using kernel.org driver
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
-- 
2.43.0