docs: networking: device drivers: convert chelsio/cxgb.txt to ReST

- add SPDX header;
- use copyright symbol;
- adjust titles and chapters, adding proper markups;
- comment out text-only TOC from html/pdf output;
- mark code blocks and literals as such;
- add notes markups;
- mark tables as such;
- mark lists as such;
- adjust identation, whitespaces and blank lines where needed;
- add to networking/index.rst.

Signed-off-by: Mauro Carvalho Chehab <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

Documentation/networking/device_drivers/chelsio/cxgb.txt Documentation/networking/device_drivers/chelsio/cxgb.rst

···
-                 Chelsio N210 10Gb Ethernet Network Controller
+.. SPDX-License-Identifier: GPL-2.0
+.. include:: <isonum.txt>
 
-                         Driver Release Notes for Linux
+=============================================
+Chelsio N210 10Gb Ethernet Network Controller
+=============================================
 
-                                 Version 2.1.1
+Driver Release Notes for Linux
 
-                                 June 20, 2005
+Version 2.1.1
 
-CONTENTS
-========
+June 20, 2005
+
+.. Contents
+
  INTRODUCTION
  FEATURES
  PERFORMANCE
···
  SUPPORT
 
 
-INTRODUCTION
+Introduction
 ============
 
  This document describes the Linux driver for Chelsio 10Gb Ethernet Network
···
  compatible with the Chelsio N110 model 10Gb NICs.
 
 
-FEATURES
+Features
 ========
 
- Adaptive Interrupts (adaptive-rx)
- ---------------------------------
+Adaptive Interrupts (adaptive-rx)
+---------------------------------
 
   This feature provides an adaptive algorithm that adjusts the interrupt
   coalescing parameters, allowing the driver to dynamically adapt the latency
···
   ethtool manpage for additional usage information.
 
   By default, adaptive-rx is disabled.
-  To enable adaptive-rx:
+  To enable adaptive-rx::
 
       ethtool -C <interface> adaptive-rx on
 
-  To disable adaptive-rx, use ethtool:
+  To disable adaptive-rx, use ethtool::
 
       ethtool -C <interface> adaptive-rx off
 
   After disabling adaptive-rx, the timer latency value will be set to 50us.
-  You may set the timer latency after disabling adaptive-rx:
+  You may set the timer latency after disabling adaptive-rx::
 
       ethtool -C <interface> rx-usecs <microseconds>
 
-  An example to set the timer latency value to 100us on eth0:
+  An example to set the timer latency value to 100us on eth0::
 
       ethtool -C eth0 rx-usecs 100
 
-  You may also provide a timer latency value while disabling adaptive-rx:
+  You may also provide a timer latency value while disabling adaptive-rx::
 
       ethtool -C <interface> adaptive-rx off rx-usecs <microseconds>
 
···
   will be set to the specified value until changed by the user or until
   adaptive-rx is enabled.
 
-  To view the status of the adaptive-rx and timer latency values:
+  To view the status of the adaptive-rx and timer latency values::
 
       ethtool -c <interface>
 
 
- TCP Segmentation Offloading (TSO) Support
- -----------------------------------------
+TCP Segmentation Offloading (TSO) Support
+-----------------------------------------
 
   This feature, also known as "large send", enables a system's protocol stack
   to offload portions of outbound TCP processing to a network interface card
···
   Please see the ethtool manpage for additional usage information.
 
   By default, TSO is enabled.
-  To disable TSO:
+  To disable TSO::
 
       ethtool -K <interface> tso off
 
-  To enable TSO:
+  To enable TSO::
 
       ethtool -K <interface> tso on
 
-  To view the status of TSO:
+  To view the status of TSO::
 
       ethtool -k <interface>
 
 
-PERFORMANCE
+Performance
 ===========
 
  The following information is provided as an example of how to change system
···
  your system. You may want to write a script that runs at boot-up which
  includes the optimal settings for your system.
 
-  Setting PCI Latency Timer:
-      setpci -d 1425:* 0x0c.l=0x0000F800
+  Setting PCI Latency Timer::
 
-  Disabling TCP timestamp:
+      setpci -d 1425::
+
+* 0x0c.l=0x0000F800
+
+  Disabling TCP timestamp::
+
       sysctl -w net.ipv4.tcp_timestamps=0
 
-  Disabling SACK:
+  Disabling SACK::
+
       sysctl -w net.ipv4.tcp_sack=0
 
-  Setting large number of incoming connection requests:
+  Setting large number of incoming connection requests::
+
       sysctl -w net.ipv4.tcp_max_syn_backlog=3000
 
-  Setting maximum receive socket buffer size:
+  Setting maximum receive socket buffer size::
+
       sysctl -w net.core.rmem_max=1024000
 
-  Setting maximum send socket buffer size:
+  Setting maximum send socket buffer size::
+
       sysctl -w net.core.wmem_max=1024000
 
-  Set smp_affinity (on a multiprocessor system) to a single CPU:
+  Set smp_affinity (on a multiprocessor system) to a single CPU::
+
       echo 1 > /proc/irq/<interrupt_number>/smp_affinity
 
-  Setting default receive socket buffer size:
+  Setting default receive socket buffer size::
+
       sysctl -w net.core.rmem_default=524287
 
-  Setting default send socket buffer size:
+  Setting default send socket buffer size::
+
       sysctl -w net.core.wmem_default=524287
 
-  Setting maximum option memory buffers:
+  Setting maximum option memory buffers::
+
       sysctl -w net.core.optmem_max=524287
 
-  Setting maximum backlog (# of unprocessed packets before kernel drops):
+  Setting maximum backlog (# of unprocessed packets before kernel drops)::
+
       sysctl -w net.core.netdev_max_backlog=300000
 
-  Setting TCP read buffers (min/default/max):
+  Setting TCP read buffers (min/default/max)::
+
       sysctl -w net.ipv4.tcp_rmem="10000000 10000000 10000000"
 
-  Setting TCP write buffers (min/pressure/max):
+  Setting TCP write buffers (min/pressure/max)::
+
       sysctl -w net.ipv4.tcp_wmem="10000000 10000000 10000000"
 
-  Setting TCP buffer space (min/pressure/max):
+  Setting TCP buffer space (min/pressure/max)::
+
       sysctl -w net.ipv4.tcp_mem="10000000 10000000 10000000"
 
   TCP window size for single connections:
+
    The receive buffer (RX_WINDOW) size must be at least as large as the
    Bandwidth-Delay Product of the communication link between the sender and
    receiver. Due to the variations of RTT, you may want to increase the buffer
    size up to 2 times the Bandwidth-Delay Product. Reference page 289 of
    "TCP/IP Illustrated, Volume 1, The Protocols" by W. Richard Stevens.
-   At 10Gb speeds, use the following formula:
+
+   At 10Gb speeds, use the following formula::
+
        RX_WINDOW >= 1.25MBytes * RTT(in milliseconds)
        Example for RTT with 100us: RX_WINDOW = (1,250,000 * 0.1) = 125,000
+
    RX_WINDOW sizes of 256KB - 512KB should be sufficient.
-   Setting the min, max, and default receive buffer (RX_WINDOW) size:
+
+   Setting the min, max, and default receive buffer (RX_WINDOW) size::
+
        sysctl -w net.ipv4.tcp_rmem="<min> <default> <max>"
 
   TCP window size for multiple connections:
···
    not supported on the machine. Experimentation may be necessary to attain
    the correct value. This method is provided as a starting point for the
    correct receive buffer size.
+
    Setting the min, max, and default receive buffer (RX_WINDOW) size is
    performed in the same manner as single connection.
 
 
-DRIVER MESSAGES
+Driver Messages
 ===============
 
  The following messages are the most common messages logged by syslog. These
  may be found in /var/log/messages.
 
-  Driver up:
+  Driver up::
+
      Chelsio Network Driver - version 2.1.1
 
-  NIC detected:
+  NIC detected::
+
      eth#: Chelsio N210 1x10GBaseX NIC (rev #), PCIX 133MHz/64-bit
 
-  Link up:
+  Link up::
+
      eth#: link is up at 10 Gbps, full duplex
 
-  Link down:
+  Link down::
+
      eth#: link is down
 
 
-KNOWN ISSUES
+Known Issues
 ============
 
  These issues have been identified during testing. The following information
···
 
       To eliminate the TCP retransmits, set smp_affinity on the particular
       interrupt to a single CPU. You can locate the interrupt (IRQ) used on
-      the N110/N210 by using ifconfig:
-          ifconfig <dev_name> | grep Interrupt
-      Set the smp_affinity to a single CPU:
-          echo 1 > /proc/irq/<interrupt_number>/smp_affinity
+      the N110/N210 by using ifconfig::
+
+	  ifconfig <dev_name> | grep Interrupt
+
+      Set the smp_affinity to a single CPU::
+
+	  echo 1 > /proc/irq/<interrupt_number>/smp_affinity
 
       It is highly suggested that you do not run the irqbalance daemon on your
       system, as this will change any smp_affinity setting you have applied.
       The irqbalance daemon runs on a 10 second interval and binds interrupts
-      to the least loaded CPU determined by the daemon. To disable this daemon:
-          chkconfig --level 2345 irqbalance off
+      to the least loaded CPU determined by the daemon. To disable this daemon::
+
+	  chkconfig --level 2345 irqbalance off
 
       By default, some Linux distributions enable the kernel feature,
       irqbalance, which performs the same function as the daemon. To disable
-      this feature, add the following line to your bootloader:
-          noirqbalance
+      this feature, add the following line to your bootloader::
 
-          Example using the Grub bootloader:
-              title Red Hat Enterprise Linux AS (2.4.21-27.ELsmp)
-              root (hd0,0)
-              kernel /vmlinuz-2.4.21-27.ELsmp ro root=/dev/hda3 noirqbalance
-              initrd /initrd-2.4.21-27.ELsmp.img
+	  noirqbalance
+
+	  Example using the Grub bootloader::
+
+	      title Red Hat Enterprise Linux AS (2.4.21-27.ELsmp)
+	      root (hd0,0)
+	      kernel /vmlinuz-2.4.21-27.ELsmp ro root=/dev/hda3 noirqbalance
+	      initrd /initrd-2.4.21-27.ELsmp.img
 
   2. After running insmod, the driver is loaded and the incorrect network
      interface is brought up without running ifup.
···
       AMD's provides three workarounds for this problem, however, Chelsio
       recommends the first option for best performance with this bug:
 
-        For 133Mhz secondary bus operation, limit the transaction length and
-        the number of outstanding transactions, via BIOS configuration
-        programming of the PCI-X card, to the following:
+	For 133Mhz secondary bus operation, limit the transaction length and
+	the number of outstanding transactions, via BIOS configuration
+	programming of the PCI-X card, to the following:
 
-           Data Length (bytes): 1k
-           Total allowed outstanding transactions: 2
+	   Data Length (bytes): 1k
+
+	   Total allowed outstanding transactions: 2
 
       Please refer to AMD 8131-HT/PCI-X Errata 26310 Rev 3.08 August 2004,
       section 56, "133-MHz Mode Split Completion Data Corruption" for more
···
       have issues with these settings, please revert to the "safe" settings
       and duplicate the problem before submitting a bug or asking for support.
 
-      NOTE: The default setting on most systems is 8 outstanding transactions
-            and 2k bytes data length.
+      .. note::
+
+	    The default setting on most systems is 8 outstanding transactions
+	    and 2k bytes data length.
 
   4. On multiprocessor systems, it has been noted that an application which
      is handling 10Gb networking can switch between CPUs causing degraded
···
       particular CPU: runon 0 ifup eth0
 
 
-SUPPORT
+Support
 =======
 
  If you have problems with the software or hardware, please contact our
  customer support team via email at [e-mail] or check our website
  at http://www.chelsio.com
 
-===============================================================================
+-------------------------------------------------------------------------------
+
+::
 
  Chelsio Communications
  370 San Aleso Ave.
···
 with this program; if not, write to the Free Software Foundation, Inc.,
 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
-THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
+THIS SOFTWARE IS PROVIDED ``AS IS`` AND WITHOUT ANY EXPRESS OR IMPLIED
 WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 
- Copyright (c) 2003-2005 Chelsio Communications. All rights reserved.
-
-===============================================================================
+Copyright |copy| 2003-2005 Chelsio Communications. All rights reserved.

Documentation/networking/device_drivers/index.rst

···
    3com/vortex
    amazon/ena
    aquantia/atlantic
+   chelsio/cxgb
 
 .. only::  subproject and html
 

drivers/net/ethernet/chelsio/Kconfig

···
 	  This driver supports Chelsio gigabit and 10-gigabit
 	  Ethernet cards. More information about adapter features and
 	  performance tuning is in
-	  <file:Documentation/networking/device_drivers/chelsio/cxgb.txt>.
+	  <file:Documentation/networking/device_drivers/chelsio/cxgb.rst>.
 
 	  For general information about Chelsio and our products, visit
 	  our website at <http://www.chelsio.com>.