qemu-rocker is a simulated ethernet switch device.  The device supports
up to 62 front-panel ports and supports L2 and L3 switching and routing
functions.  The device presents a single PCI device for the switch, with
a memory-mapped register space for device driver access.

qemu-rocker currently supports a switch model based on Broadcom's OF-DPA
switch.  See Broadcom's OF-DPA specification version 1.0 for more info on
OF-DPA.  qemu-rocker could support other switch models in the future.

Programmer's Reference Guide for qemu-rocker is here:

    hw/net/rocker/reg_guide.txt


Development
===========

Note: make sure you checkout the rocker branch once you clone the repo.

$ git checkout rocker

qemu-rocker device is located in hw/net/rocker.

There is a companion development project for a Linux device driver for
the rocker device, also on github at net-next-rocker.   net-next-rocker
includes the device driver (rocker.ko) and proposed changes to the
Linux kernel to support a new switch device driver model (swdev).  The
kernel changes are currently under review.


Building
--------

$ ./configure --target-list=x86_64-softmmu --extra-cflags=-DDEBUG_ROCKER
$ make -j16

(Assuming target is x86_64; adjust --target-list accordingly for other
targets).

-DDEBUG_ROCKER is optional and is used to provide additional run-time
debug msgs to track device operation.


Running
-------

Verify rocker device is present:

$ qemu-system-x86_64 -device help 2>&1 | grep rocker
name "rocker", bus PCI, desc "Rocker Switch"

Device options:

$ qemu-system-x86_64 -device rocker,help
rocker.name=str
rocker.fp_start_macaddr=macaddr
rocker.switch_id=uint64
rocker.len-ports=uint32
rocker.addr=pci-devfn
rocker.romfile=str
rocker.rombar=uint32
rocker.multifunction=on/off
rocker.command_serr_enable=on/off

The relevant options are name, fp_start_macaddr, switch_id, len-ports.
There is also a ports option not list above.  An example qemu command
line option for a 4-port switch is:

    -device rocker,name=sw1,len-ports=4,ports[0]=dev0,ports[1]=dev1, \
         ports[2]=dev2,ports[3]=dev3

The switch is name "sw1".  The 4 ports are connected to 4 qemu netdev
devices, dev0-3.  The qemu netdev devices could be taps or sockets,
for example.  A fuller example using UDP scoket netdevs would be:

    -device rocker,name=sw1,len-ports=4,ports[0]=dev0,ports[1]=dev1, \
        ports[2]=dev2,ports[3]=dev3 -netdev socket,udp=127.0.0.1:1204, \
        localaddr=127.0.0.1:1215,id=dev0 -netdev socket, \
        udp=127.0.0.1:1205,localaddr=127.0.0.1:1219,id=dev1 \
        -netdev socket,udp=127.0.0.1:1206,localaddr=127.0.0.1:1211, \
        id=dev2 -netdev socket,udp=127.0.0.1:1207, \
        localaddr=127.0.0.1:1223,id=dev3

This would connect the 4 rocker switch ports to UDP sockets on
localhost.  Other programs (such as other VMs) can be connected to
the other ends of the UDP sockets to create virtual "wires".

Debugging
---------

qemu monitor for the VM can be used to examine qemu-rocker device's
internal state.  This can be done at run-time while switch is operational.

Examples:

(qemu) rocker sw1
name: sw1
id: 0x0000013512005452
ports: 4

(qemu) rocker-ports sw1
            ena/    speed/ auto
      port  link    duplex neg?
     sw1.1  up     10G  FD  No
     sw1.2  up     10G  FD  No
     sw1.3  !ena   10G  FD  No
     sw1.4  !ena   10G  FD  No

(qemu) rocker-of-dpa-flows sw1
prio tbl hits key(mask) --> actions
2    60       lport 1 vlan 1 LLDP src 00:02:00:00:02:00 dst 01:80:c2:00:00:0e
2    60       lport 1 vlan 1 ARP src 00:02:00:00:02:00 dst 00:02:00:00:03:00
2    60       lport 2 vlan 2 IPv6 src 00:02:00:00:03:00 dst 33:33:ff:00:00:02 proto 58
3    50       vlan 2 dst 33:33:ff:00:00:02 --> write group 0x32000001 goto tbl 60
2    60       lport 2 vlan 2 IPv6 src 00:02:00:00:03:00 dst 33:33:ff:00:03:00 proto 58
3    50  1    vlan 2 dst 33:33:ff:00:03:00 --> write group 0x32000001 goto tbl 60
2    60       lport 2 vlan 2 ARP src 00:02:00:00:03:00 dst 00:02:00:00:02:00
3    50  2    vlan 2 dst 00:02:00:00:02:00 --> write group 0x02000001 goto tbl 60
2    60  1    lport 2 vlan 2 IP src 00:02:00:00:03:00 dst 00:02:00:00:02:00 proto 1
3    50  2    vlan 1 dst 00:02:00:00:03:00 --> write group 0x01000002 goto tbl 60
2    60  1    lport 1 vlan 1 IP src 00:02:00:00:02:00 dst 00:02:00:00:03:00 proto 1
2    60       lport 1 vlan 1 IPv6 src 00:02:00:00:02:00 dst 33:33:ff:00:00:01 proto 58
3    50       vlan 1 dst 33:33:ff:00:00:01 --> write group 0x31000000 goto tbl 60
2    60       lport 1 vlan 1 IPv6 src 00:02:00:00:02:00 dst 33:33:ff:00:02:00 proto 58
3    50  1    vlan 1 dst 33:33:ff:00:02:00 --> write group 0x31000000 goto tbl 60
1    60  173  lport 2 vlan 2 LLDP src <any> dst 01:80:c2:00:00:0e --> write group 0x02000000
1    60  6    lport 2 vlan 2 IPv6 src <any> dst <any> --> write group 0x02000000
1    60  174  lport 1 vlan 1 LLDP src <any> dst 01:80:c2:00:00:0e --> write group 0x01000000
1    60  174  lport 2 vlan 2 IP src <any> dst <any> --> write group 0x02000000
1    60  6    lport 1 vlan 1 IPv6 src <any> dst <any> --> write group 0x01000000
1    60  181  lport 2 vlan 2 ARP src <any> dst <any> --> write group 0x02000000
1    10  715  lport 2 --> apply new vlan 2 goto tbl 20
1    60  177  lport 1 vlan 1 ARP src <any> dst <any> --> write group 0x01000000
1    60  174  lport 1 vlan 1 IP src <any> dst <any> --> write group 0x01000000
1    10  717  lport 1 --> apply new vlan 1 goto tbl 20
1    0   1432 lport 0(0xffff) --> goto tbl 10

(qemu) rocker-of-dpa-groups sw1
id (decode) --> buckets
0x32000001 (type L2 multicast vlan 2 index 1) --> groups [0x02000001,0x02000000]
0x02000001 (type L2 interface vlan 2 lport 1) --> pop vlan out lport 1
0x01000002 (type L2 interface vlan 1 lport 2) --> pop vlan out lport 2
0x02000000 (type L2 interface vlan 2 lport 0) --> pop vlan out lport 0
0x01000000 (type L2 interface vlan 1 lport 0) --> pop vlan out lport 0
0x31000000 (type L2 multicast vlan 1 index 0) --> groups [0x01000002,0x01000000]