dw-xdata-pcie: Update outdated info and improve text format

Removes old information related to the stop file interface in sysfs left
by mistake during patch revision.

Improves the document text format to be more user-friendly and adds
basic driver related information, such as support, datasheet, and author.

Signed-off-by: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Link: https://lore.kernel.org/r/4e72f931474a784d478e5a67961ecf116911997a.1618066164.git.gustavo.pimentel@synopsys.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Documentation/misc-devices/dw-xdata-pcie.rst

@@ -4,37 +4,61 @@
 Driver for Synopsys DesignWare PCIe traffic generator (also known as xData)
 ===========================================================================
 
+Supported chips:
+Synopsys DesignWare PCIe prototype solution
+
+Datasheet:
+Not freely available
+
+Author:
+Gustavo Pimentel <gustavo.pimentel@synopsys.com>
+
+Description
+-----------
+
 This driver should be used as a host-side (Root Complex) driver and Synopsys
 DesignWare prototype that includes this IP.
 
-The "dw-xdata-pcie" driver can be used to enable/disable PCIe traffic
+The dw-xdata-pcie driver can be used to enable/disable PCIe traffic
 generator in either direction (mutual exclusion) besides allowing the
 PCIe link performance analysis.
 
 The interaction with this driver is done through the module parameter and
 can be changed in runtime. The driver outputs the requested command state
-information to /var/log/kern.log or dmesg.
+information to ``/var/log/kern.log`` or dmesg.
 
-Request write TLPs traffic generation - Root Complex to Endpoint direction
-- Command:
-echo 1 > /sys/class/misc/dw-xdata-pcie/write
+Example
+-------
 
-Get write TLPs traffic link throughput in MB/s
-- Command:
-cat /sys/class/misc/dw-xdata-pcie/write
-- Output example:
-204
+Write TLPs traffic generation - Root Complex to Endpoint direction
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-Request read TLPs traffic generation - Endpoint to Root Complex direction:
-- Command:
-echo 1 > /sys/class/misc/dw-xdata-pcie/read
+Generate traffic::
 
-Get read TLPs traffic link throughput in MB/s
-- Command:
-cat /sys/class/misc/dw-xdata-pcie/read
-- Output example:
-199
+ # echo 1 > /sys/class/misc/dw-xdata-pcie.0/write
+
+Get link throughput in MB/s::
+
+ # cat /sys/class/misc/dw-xdata-pcie.0/write
+ 204
+
+Stop traffic in any direction::
+
+ # echo 0 > /sys/class/misc/dw-xdata-pcie.0/write
+
+Read TLPs traffic generation - Endpoint to Root Complex direction
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Generate traffic::
+
+ # echo 1 > /sys/class/misc/dw-xdata-pcie.0/read
+
+Get link throughput in MB/s::
+
+ # cat /sys/class/misc/dw-xdata-pcie.0/read
+ 199
+
+Stop traffic in any direction::
+
+ # echo 0 > /sys/class/misc/dw-xdata-pcie.0/read
 
-Request to stop any current TLP transfer:
-- Command:
-echo 1 > /sys/class/misc/dw-xdata-pcie/stop