Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 141 insertions, 0 deletions

diff --git a/kernel/Documentation/networking/s2io.txt b/kernel/Documentation/networking/s2io.txt
new file mode 100644
index 000000000..0362a42f7
--- /dev/null
+++ b/kernel/Documentation/networking/s2io.txt
@@ -0,0 +1,141 @@
+Release notes for Neterion's (Formerly S2io) Xframe I/II PCI-X 10GbE driver.
+
+Contents
+=======
+- 1.  Introduction
+- 2.  Identifying the adapter/interface
+- 3.  Features supported
+- 4.  Command line parameters
+- 5.  Performance suggestions
+- 6.  Available Downloads 
+
+
+1.	Introduction:
+This Linux driver supports Neterion's Xframe I PCI-X 1.0 and
+Xframe II PCI-X 2.0 adapters. It supports several features 
+such as jumbo frames, MSI/MSI-X, checksum offloads, TSO, UFO and so on.
+See below for complete list of features.
+All features are supported for both IPv4 and IPv6.
+
+2.	Identifying the adapter/interface:
+a. Insert the adapter(s) in your system.
+b. Build and load driver 
+# insmod s2io.ko
+c. View log messages
+# dmesg | tail -40
+You will see messages similar to:
+eth3: Neterion Xframe I 10GbE adapter (rev 3), Version 2.0.9.1, Intr type INTA
+eth4: Neterion Xframe II 10GbE adapter (rev 2), Version 2.0.9.1, Intr type INTA
+eth4: Device is on 64 bit 133MHz PCIX(M1) bus
+
+The above messages identify the adapter type(Xframe I/II), adapter revision,
+driver version, interface name(eth3, eth4), Interrupt type(INTA, MSI, MSI-X).
+In case of Xframe II, the PCI/PCI-X bus width and frequency are displayed
+as well.
+
+To associate an interface with a physical adapter use "ethtool -p <ethX>".
+The corresponding adapter's LED will blink multiple times.
+
+3.	Features supported:
+a. Jumbo frames. Xframe I/II supports MTU up to 9600 bytes,
+modifiable using ip command.
+
+b. Offloads. Supports checksum offload(TCP/UDP/IP) on transmit
+and receive, TSO.
+
+c. Multi-buffer receive mode. Scattering of packet across multiple
+buffers. Currently driver supports 2-buffer mode which yields
+significant performance improvement on certain platforms(SGI Altix,
+IBM xSeries).
+
+d. MSI/MSI-X. Can be enabled on platforms which support this feature
+(IA64, Xeon) resulting in noticeable performance improvement(up to 7%
+on certain platforms).
+
+e. Statistics. Comprehensive MAC-level and software statistics displayed
+using "ethtool -S" option.
+
+f. Multi-FIFO/Ring. Supports up to 8 transmit queues and receive rings,
+with multiple steering options.
+
+4.  Command line parameters
+a. tx_fifo_num
+Number of transmit queues
+Valid range: 1-8
+Default: 1
+
+b. rx_ring_num
+Number of receive rings
+Valid range: 1-8
+Default: 1
+
+c. tx_fifo_len
+Size of each transmit queue
+Valid range: Total length of all queues should not exceed 8192
+Default: 4096
+
+d. rx_ring_sz 
+Size of each receive ring(in 4K blocks)
+Valid range: Limited by memory on system
+Default: 30 
+
+e. intr_type
+Specifies interrupt type. Possible values 0(INTA), 2(MSI-X)
+Valid values: 0, 2
+Default: 2
+
+5.  Performance suggestions
+General:
+a. Set MTU to maximum(9000 for switch setup, 9600 in back-to-back configuration)
+b. Set TCP windows size to optimal value. 
+For instance, for MTU=1500 a value of 210K has been observed to result in 
+good performance.
+# sysctl -w net.ipv4.tcp_rmem="210000 210000 210000"
+# sysctl -w net.ipv4.tcp_wmem="210000 210000 210000"
+For MTU=9000, TCP window size of 10 MB is recommended.
+# sysctl -w net.ipv4.tcp_rmem="10000000 10000000 10000000"
+# sysctl -w net.ipv4.tcp_wmem="10000000 10000000 10000000"
+
+Transmit performance:
+a. By default, the driver respects BIOS settings for PCI bus parameters. 
+However, you may want to experiment with PCI bus parameters 
+max-split-transactions(MOST) and MMRBC (use setpci command). 
+A MOST value of 2 has been found optimal for Opterons and 3 for Itanium.  
+It could be different for your hardware.  
+Set MMRBC to 4K**.
+
+For example you can set 
+For opteron
+#setpci -d 17d5:* 62=1d 
+For Itanium
+#setpci -d 17d5:* 62=3d 
+
+For detailed description of the PCI registers, please see Xframe User Guide.
+
+b. Ensure Transmit Checksum offload is enabled. Use ethtool to set/verify this 
+parameter.
+c. Turn on TSO(using "ethtool -K")
+# ethtool -K <ethX> tso on
+
+Receive performance:
+a. By default, the driver respects BIOS settings for PCI bus parameters. 
+However, you may want to set PCI latency timer to 248.
+#setpci -d 17d5:* LATENCY_TIMER=f8
+For detailed description of the PCI registers, please see Xframe User Guide.
+b. Use 2-buffer mode. This results in large performance boost on
+certain platforms(eg. SGI Altix, IBM xSeries).
+c. Ensure Receive Checksum offload is enabled. Use "ethtool -K ethX" command to 
+set/verify this option.
+d. Enable NAPI feature(in kernel configuration Device Drivers ---> Network 
+device support --->  Ethernet (10000 Mbit) ---> S2IO 10Gbe Xframe NIC) to 
+bring down CPU utilization.
+
+** For AMD opteron platforms with 8131 chipset, MMRBC=1 and MOST=1 are 
+recommended as safe parameters.
+For more information, please review the AMD8131 errata at
+http://vip.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/
+26310_AMD-8131_HyperTransport_PCI-X_Tunnel_Revision_Guide_rev_3_18.pdf
+
+6. Support
+For further support please contact either your 10GbE Xframe NIC vendor (IBM, 
+HP, SGI etc.)