Documentation/networking/vortex.txt - kernel/quantenna - Git at Google

 Documentation/networking/vortex.txt
 Andrew Morton
 30 April 2000


 This document describes the usage and errata of the 3Com "Vortex" device
 driver for Linux, 3c59x.c.

 The driver was written by Donald Becker <becker@scyld.com>

 Don is no longer the prime maintainer of this version of the driver.
 Please report problems to one or more of:

   Andrew Morton
   Netdev mailing list <netdev@vger.kernel.org>
   Linux kernel mailing list <linux-kernel@vger.kernel.org>

 Please note the 'Reporting and Diagnosing Problems' section at the end
 of this file.


 Since kernel 2.3.99-pre6, this driver incorporates the support for the
 3c575-series Cardbus cards which used to be handled by 3c575_cb.c.

 This driver supports the following hardware:

 	3c590 Vortex 10Mbps
 	3c592 EISA 10Mbps Demon/Vortex
 	3c597 EISA Fast Demon/Vortex
 	3c595 Vortex 100baseTx
 	3c595 Vortex 100baseT4
 	3c595 Vortex 100base-MII
 	3c900 Boomerang 10baseT
 	3c900 Boomerang 10Mbps Combo
 	3c900 Cyclone 10Mbps TPO
 	3c900 Cyclone 10Mbps Combo
 	3c900 Cyclone 10Mbps TPC
 	3c900B-FL Cyclone 10base-FL
 	3c905 Boomerang 100baseTx
 	3c905 Boomerang 100baseT4
 	3c905B Cyclone 100baseTx
 	3c905B Cyclone 10/100/BNC
 	3c905B-FX Cyclone 100baseFx
 	3c905C Tornado
 	3c920B-EMB-WNM (ATI Radeon 9100 IGP)
 	3c980 Cyclone
 	3c980C Python-T
 	3cSOHO100-TX Hurricane
 	3c555 Laptop Hurricane
 	3c556 Laptop Tornado
 	3c556B Laptop Hurricane
 	3c575 [Megahertz] 10/100 LAN  CardBus
 	3c575 Boomerang CardBus
 	3CCFE575BT Cyclone CardBus
 	3CCFE575CT Tornado CardBus
 	3CCFE656 Cyclone CardBus
 	3CCFEM656B Cyclone+Winmodem CardBus
 	3CXFEM656C Tornado+Winmodem CardBus
 	3c450 HomePNA Tornado
 	3c920 Tornado
 	3c982 Hydra Dual Port A
 	3c982 Hydra Dual Port B
 	3c905B-T4
 	3c920B-EMB-WNM Tornado

 Module parameters
 =================

 There are several parameters which may be provided to the driver when
 its module is loaded.  These are usually placed in /etc/modprobe.d/*.conf
 configuration files.  Example:

 options 3c59x debug=3 rx_copybreak=300

 If you are using the PCMCIA tools (cardmgr) then the options may be
 placed in /etc/pcmcia/config.opts:

 module "3c59x" opts "debug=3 rx_copybreak=300"


 The supported parameters are:

 debug=N

   Where N is a number from 0 to 7.  Anything above 3 produces a lot
   of output in your system logs.  debug=1 is default.

 options=N1,N2,N3,...

   Each number in the list provides an option to the corresponding
   network card.  So if you have two 3c905's and you wish to provide
   them with option 0x204 you would use:

     options=0x204,0x204

   The individual options are composed of a number of bitfields which
   have the following meanings:

   Possible media type settings
 	0	10baseT
 	1	10Mbs AUI
 	2	undefined
 	3	10base2 (BNC)
 	4	100base-TX
 	5	100base-FX
 	6	MII (Media Independent Interface)
 	7	Use default setting from EEPROM
 	8       Autonegotiate
 	9       External MII
 	10      Use default setting from EEPROM

   When generating a value for the 'options' setting, the above media
   selection values may be OR'ed (or added to) the following:

   0x8000  Set driver debugging level to 7
   0x4000  Set driver debugging level to 2
   0x0400  Enable Wake-on-LAN
   0x0200  Force full duplex mode.
   0x0010  Bus-master enable bit (Old Vortex cards only)

   For example:

     insmod 3c59x options=0x204

   will force full-duplex 100base-TX, rather than allowing the usual
   autonegotiation.

 global_options=N

   Sets the `options' parameter for all 3c59x NICs in the machine.
   Entries in the `options' array above will override any setting of
   this.

 full_duplex=N1,N2,N3...

   Similar to bit 9 of 'options'.  Forces the corresponding card into
   full-duplex mode.  Please use this in preference to the `options'
   parameter.

   In fact, please don't use this at all! You're better off getting
   autonegotiation working properly.

 global_full_duplex=N1

   Sets full duplex mode for all 3c59x NICs in the machine.  Entries
   in the `full_duplex' array above will override any setting of this.

 flow_ctrl=N1,N2,N3...

   Use 802.3x MAC-layer flow control.  The 3com cards only support the
   PAUSE command, which means that they will stop sending packets for a
   short period if they receive a PAUSE frame from the link partner.

   The driver only allows flow control on a link which is operating in
   full duplex mode.

   This feature does not appear to work on the 3c905 - only 3c905B and
   3c905C have been tested.

   The 3com cards appear to only respond to PAUSE frames which are
   sent to the reserved destination address of 01:80:c2:00:00:01.  They
   do not honour PAUSE frames which are sent to the station MAC address.

 rx_copybreak=M

   The driver preallocates 32 full-sized (1536 byte) network buffers
   for receiving.  When a packet arrives, the driver has to decide
   whether to leave the packet in its full-sized buffer, or to allocate
   a smaller buffer and copy the packet across into it.

   This is a speed/space tradeoff.

   The value of rx_copybreak is used to decide when to make the copy.
   If the packet size is less than rx_copybreak, the packet is copied.
   The default value for rx_copybreak is 200 bytes.

 max_interrupt_work=N

   The driver's interrupt service routine can handle many receive and
   transmit packets in a single invocation.  It does this in a loop.
   The value of max_interrupt_work governs how many times the interrupt
   service routine will loop.  The default value is 32 loops.  If this
   is exceeded the interrupt service routine gives up and generates a
   warning message "eth0: Too much work in interrupt".

 hw_checksums=N1,N2,N3,...

   Recent 3com NICs are able to generate IPv4, TCP and UDP checksums
   in hardware.  Linux has used the Rx checksumming for a long time.
   The "zero copy" patch which is planned for the 2.4 kernel series
   allows you to make use of the NIC's DMA scatter/gather and transmit
   checksumming as well.

   The driver is set up so that, when the zerocopy patch is applied,
   all Tornado and Cyclone devices will use S/G and Tx checksums.

   This module parameter has been provided so you can override this
   decision.  If you think that Tx checksums are causing a problem, you
   may disable the feature with `hw_checksums=0'.

   If you think your NIC should be performing Tx checksumming and the
   driver isn't enabling it, you can force the use of hardware Tx
   checksumming with `hw_checksums=1'.

   The driver drops a message in the logfiles to indicate whether or
   not it is using hardware scatter/gather and hardware Tx checksums.

   Scatter/gather and hardware checksums provide considerable
   performance improvement for the sendfile() system call, but a small
   decrease in throughput for send().  There is no effect upon receive
   efficiency.

 compaq_ioaddr=N
 compaq_irq=N
 compaq_device_id=N

   "Variables to work-around the Compaq PCI BIOS32 problem"....

 watchdog=N

   Sets the time duration (in milliseconds) after which the kernel
   decides that the transmitter has become stuck and needs to be reset.
   This is mainly for debugging purposes, although it may be advantageous
   to increase this value on LANs which have very high collision rates.
   The default value is 5000 (5.0 seconds).

 enable_wol=N1,N2,N3,...

   Enable Wake-on-LAN support for the relevant interface.  Donald
   Becker's `ether-wake' application may be used to wake suspended
   machines.

   Also enables the NIC's power management support.

 global_enable_wol=N

   Sets enable_wol mode for all 3c59x NICs in the machine.  Entries in
   the `enable_wol' array above will override any setting of this.

 Media selection
 ---------------

 A number of the older NICs such as the 3c590 and 3c900 series have
 10base2 and AUI interfaces.

 Prior to January, 2001 this driver would autoeselect the 10base2 or AUI
 port if it didn't detect activity on the 10baseT port.  It would then
 get stuck on the 10base2 port and a driver reload was necessary to
 switch back to 10baseT.  This behaviour could not be prevented with a
 module option override.

 Later (current) versions of the driver _do_ support locking of the
 media type.  So if you load the driver module with

 	modprobe 3c59x options=0

 it will permanently select the 10baseT port.  Automatic selection of
 other media types does not occur.


 Transmit error, Tx status register 82
 -------------------------------------

 This is a common error which is almost always caused by another host on
 the same network being in full-duplex mode, while this host is in
 half-duplex mode.  You need to find that other host and make it run in
 half-duplex mode or fix this host to run in full-duplex mode.

 As a last resort, you can force the 3c59x driver into full-duplex mode
 with

 	options 3c59x full_duplex=1

 but this has to be viewed as a workaround for broken network gear and
 should only really be used for equipment which cannot autonegotiate.


 Additional resources
 --------------------

 Details of the device driver implementation are at the top of the source file.

 Additional documentation is available at Don Becker's Linux Drivers site:

      http://www.scyld.com/vortex.html

 Donald Becker's driver development site:

      http://www.scyld.com/network.html

 Donald's vortex-diag program is useful for inspecting the NIC's state:

      http://www.scyld.com/ethercard_diag.html

 Donald's mii-diag program may be used for inspecting and manipulating
 the NIC's Media Independent Interface subsystem:

      http://www.scyld.com/ethercard_diag.html#mii-diag

 Donald's wake-on-LAN page:

      http://www.scyld.com/wakeonlan.html

 3Com's DOS-based application for setting up the NICs EEPROMs:

 	ftp://ftp.3com.com/pub/nic/3c90x/3c90xx2.exe


 Autonegotiation notes
 ---------------------

   The driver uses a one-minute heartbeat for adapting to changes in
   the external LAN environment if link is up and 5 seconds if link is down.
   This means that when, for example, a machine is unplugged from a hubbed
   10baseT LAN plugged into a  switched 100baseT LAN, the throughput
   will be quite dreadful for up to sixty seconds.  Be patient.

   Cisco interoperability note from Walter Wong <wcw+@CMU.EDU>:

   On a side note, adding HAS_NWAY seems to share a problem with the
   Cisco 6509 switch.  Specifically, you need to change the spanning
   tree parameter for the port the machine is plugged into to 'portfast'
   mode.  Otherwise, the negotiation fails.  This has been an issue
   we've noticed for a while but haven't had the time to track down.

   Cisco switches    (Jeff Busch <jbusch@deja.com>)

     My "standard config" for ports to which PC's/servers connect directly:

         interface FastEthernet0/N
         description machinename
         load-interval 30
         spanning-tree portfast

     If autonegotiation is a problem, you may need to specify "speed
     100" and "duplex full" as well (or "speed 10" and "duplex half").

     WARNING: DO NOT hook up hubs/switches/bridges to these
     specially-configured ports! The switch will become very confused.


 Reporting and diagnosing problems
 ---------------------------------

 Maintainers find that accurate and complete problem reports are
 invaluable in resolving driver problems.  We are frequently not able to
 reproduce problems and must rely on your patience and efforts to get to
 the bottom of the problem.

 If you believe you have a driver problem here are some of the
 steps you should take:

 - Is it really a driver problem?

    Eliminate some variables: try different cards, different
    computers, different cables, different ports on the switch/hub,
    different versions of the kernel or of the driver, etc.

 - OK, it's a driver problem.

    You need to generate a report.  Typically this is an email to the
    maintainer and/or netdev@vger.kernel.org.  The maintainer's
    email address will be in the driver source or in the MAINTAINERS file.

 - The contents of your report will vary a lot depending upon the
   problem.  If it's a kernel crash then you should refer to the
   REPORTING-BUGS file.

   But for most problems it is useful to provide the following:

    o Kernel version, driver version

    o A copy of the banner message which the driver generates when
      it is initialised.  For example:

      eth0: 3Com PCI 3c905C Tornado at 0xa400,  00:50:da:6a:88:f0, IRQ 19
      8K byte-wide RAM 5:3 Rx:Tx split, autoselect/Autonegotiate interface.
      MII transceiver found at address 24, status 782d.
      Enabling bus-master transmits and whole-frame receives.

      NOTE: You must provide the `debug=2' modprobe option to generate
      a full detection message.  Please do this:

 	modprobe 3c59x debug=2

    o If it is a PCI device, the relevant output from 'lspci -vx', eg:

      00:09.0 Ethernet controller: 3Com Corporation 3c905C-TX [Fast Etherlink] (rev 74)
              Subsystem: 3Com Corporation: Unknown device 9200
              Flags: bus master, medium devsel, latency 32, IRQ 19
              I/O ports at a400 [size=128]
              Memory at db000000 (32-bit, non-prefetchable) [size=128]
              Expansion ROM at <unassigned> [disabled] [size=128K]
              Capabilities: [dc] Power Management version 2
      00: b7 10 00 92 07 00 10 02 74 00 00 02 08 20 00 00
      10: 01 a4 00 00 00 00 00 db 00 00 00 00 00 00 00 00
      20: 00 00 00 00 00 00 00 00 00 00 00 00 b7 10 00 10
      30: 00 00 00 00 dc 00 00 00 00 00 00 00 05 01 0a 0a

    o A description of the environment: 10baseT? 100baseT?
      full/half duplex? switched or hubbed?

    o Any additional module parameters which you may be providing to the driver.

    o Any kernel logs which are produced.  The more the merrier.
      If this is a large file and you are sending your report to a
      mailing list, mention that you have the logfile, but don't send
      it.  If you're reporting direct to the maintainer then just send
      it.

      To ensure that all kernel logs are available, add the
      following line to /etc/syslog.conf:

          kern.* /var/log/messages

      Then restart syslogd with:

          /etc/rc.d/init.d/syslog restart

      (The above may vary, depending upon which Linux distribution you use).

     o If your problem is reproducible then that's great.  Try the
       following:

       1) Increase the debug level.  Usually this is done via:

          a) modprobe driver debug=7
          b) In /etc/modprobe.d/driver.conf:
             options driver debug=7

       2) Recreate the problem with the higher debug level,
          send all logs to the maintainer.

       3) Download you card's diagnostic tool from Donald
          Becker's website <http://www.scyld.com/ethercard_diag.html>.
          Download mii-diag.c as well.  Build these.

          a) Run 'vortex-diag -aaee' and 'mii-diag -v' when the card is
             working correctly.  Save the output.

          b) Run the above commands when the card is malfunctioning.  Send
             both sets of output.

 Finally, please be patient and be prepared to do some work.  You may
 end up working on this problem for a week or more as the maintainer
 asks more questions, asks for more tests, asks for patches to be
 applied, etc.  At the end of it all, the problem may even remain
 unresolved.
	Documentation/networking/vortex.txt
	Andrew Morton
	30 April 2000


	This document describes the usage and errata of the 3Com "Vortex" device
	driver for Linux, 3c59x.c.

	The driver was written by Donald Becker <becker@scyld.com>

	Don is no longer the prime maintainer of this version of the driver.
	Please report problems to one or more of:

	Andrew Morton
	Netdev mailing list <netdev@vger.kernel.org>
	Linux kernel mailing list <linux-kernel@vger.kernel.org>

	Please note the 'Reporting and Diagnosing Problems' section at the end
	of this file.


	Since kernel 2.3.99-pre6, this driver incorporates the support for the
	3c575-series Cardbus cards which used to be handled by 3c575_cb.c.

	This driver supports the following hardware:

	3c590 Vortex 10Mbps
	3c592 EISA 10Mbps Demon/Vortex
	3c597 EISA Fast Demon/Vortex
	3c595 Vortex 100baseTx
	3c595 Vortex 100baseT4
	3c595 Vortex 100base-MII
	3c900 Boomerang 10baseT
	3c900 Boomerang 10Mbps Combo
	3c900 Cyclone 10Mbps TPO
	3c900 Cyclone 10Mbps Combo
	3c900 Cyclone 10Mbps TPC
	3c900B-FL Cyclone 10base-FL
	3c905 Boomerang 100baseTx
	3c905 Boomerang 100baseT4
	3c905B Cyclone 100baseTx
	3c905B Cyclone 10/100/BNC
	3c905B-FX Cyclone 100baseFx
	3c905C Tornado
	3c920B-EMB-WNM (ATI Radeon 9100 IGP)
	3c980 Cyclone
	3c980C Python-T
	3cSOHO100-TX Hurricane
	3c555 Laptop Hurricane
	3c556 Laptop Tornado
	3c556B Laptop Hurricane
	3c575 [Megahertz] 10/100 LAN CardBus
	3c575 Boomerang CardBus
	3CCFE575BT Cyclone CardBus
	3CCFE575CT Tornado CardBus
	3CCFE656 Cyclone CardBus
	3CCFEM656B Cyclone+Winmodem CardBus
	3CXFEM656C Tornado+Winmodem CardBus
	3c450 HomePNA Tornado
	3c920 Tornado
	3c982 Hydra Dual Port A
	3c982 Hydra Dual Port B
	3c905B-T4
	3c920B-EMB-WNM Tornado

	Module parameters
	=================

	There are several parameters which may be provided to the driver when
	its module is loaded. These are usually placed in /etc/modprobe.d/*.conf
	configuration files. Example:

	options 3c59x debug=3 rx_copybreak=300

	If you are using the PCMCIA tools (cardmgr) then the options may be
	placed in /etc/pcmcia/config.opts:

	module "3c59x" opts "debug=3 rx_copybreak=300"


	The supported parameters are:

	debug=N

	Where N is a number from 0 to 7. Anything above 3 produces a lot
	of output in your system logs. debug=1 is default.

	options=N1,N2,N3,...

	Each number in the list provides an option to the corresponding
	network card. So if you have two 3c905's and you wish to provide
	them with option 0x204 you would use:

	options=0x204,0x204

	The individual options are composed of a number of bitfields which
	have the following meanings:

	Possible media type settings
	0 10baseT
	1 10Mbs AUI
	2 undefined
	3 10base2 (BNC)
	4 100base-TX
	5 100base-FX
	6 MII (Media Independent Interface)
	7 Use default setting from EEPROM
	8 Autonegotiate
	9 External MII
	10 Use default setting from EEPROM

	When generating a value for the 'options' setting, the above media
	selection values may be OR'ed (or added to) the following:

	0x8000 Set driver debugging level to 7
	0x4000 Set driver debugging level to 2
	0x0400 Enable Wake-on-LAN
	0x0200 Force full duplex mode.
	0x0010 Bus-master enable bit (Old Vortex cards only)

	For example:

	insmod 3c59x options=0x204

	will force full-duplex 100base-TX, rather than allowing the usual
	autonegotiation.

	global_options=N

	Sets the `options' parameter for all 3c59x NICs in the machine.
	Entries in the `options' array above will override any setting of
	this.

	full_duplex=N1,N2,N3...

	Similar to bit 9 of 'options'. Forces the corresponding card into
	full-duplex mode. Please use this in preference to the `options'
	parameter.

	In fact, please don't use this at all! You're better off getting
	autonegotiation working properly.

	global_full_duplex=N1

	Sets full duplex mode for all 3c59x NICs in the machine. Entries
	in the `full_duplex' array above will override any setting of this.

	flow_ctrl=N1,N2,N3...

	Use 802.3x MAC-layer flow control. The 3com cards only support the
	PAUSE command, which means that they will stop sending packets for a
	short period if they receive a PAUSE frame from the link partner.

	The driver only allows flow control on a link which is operating in
	full duplex mode.

	This feature does not appear to work on the 3c905 - only 3c905B and
	3c905C have been tested.

	The 3com cards appear to only respond to PAUSE frames which are
	sent to the reserved destination address of 01:80:c2:00:00:01. They
	do not honour PAUSE frames which are sent to the station MAC address.

	rx_copybreak=M

	The driver preallocates 32 full-sized (1536 byte) network buffers
	for receiving. When a packet arrives, the driver has to decide
	whether to leave the packet in its full-sized buffer, or to allocate
	a smaller buffer and copy the packet across into it.

	This is a speed/space tradeoff.

	The value of rx_copybreak is used to decide when to make the copy.
	If the packet size is less than rx_copybreak, the packet is copied.
	The default value for rx_copybreak is 200 bytes.

	max_interrupt_work=N

	The driver's interrupt service routine can handle many receive and
	transmit packets in a single invocation. It does this in a loop.
	The value of max_interrupt_work governs how many times the interrupt
	service routine will loop. The default value is 32 loops. If this
	is exceeded the interrupt service routine gives up and generates a
	warning message "eth0: Too much work in interrupt".

	hw_checksums=N1,N2,N3,...

	Recent 3com NICs are able to generate IPv4, TCP and UDP checksums
	in hardware. Linux has used the Rx checksumming for a long time.
	The "zero copy" patch which is planned for the 2.4 kernel series
	allows you to make use of the NIC's DMA scatter/gather and transmit
	checksumming as well.

	The driver is set up so that, when the zerocopy patch is applied,
	all Tornado and Cyclone devices will use S/G and Tx checksums.

	This module parameter has been provided so you can override this
	decision. If you think that Tx checksums are causing a problem, you
	may disable the feature with `hw_checksums=0'.

	If you think your NIC should be performing Tx checksumming and the
	driver isn't enabling it, you can force the use of hardware Tx
	checksumming with `hw_checksums=1'.

	The driver drops a message in the logfiles to indicate whether or
	not it is using hardware scatter/gather and hardware Tx checksums.

	Scatter/gather and hardware checksums provide considerable
	performance improvement for the sendfile() system call, but a small
	decrease in throughput for send(). There is no effect upon receive
	efficiency.

	compaq_ioaddr=N
	compaq_irq=N
	compaq_device_id=N

	"Variables to work-around the Compaq PCI BIOS32 problem"....

	watchdog=N

	Sets the time duration (in milliseconds) after which the kernel
	decides that the transmitter has become stuck and needs to be reset.
	This is mainly for debugging purposes, although it may be advantageous
	to increase this value on LANs which have very high collision rates.
	The default value is 5000 (5.0 seconds).

	enable_wol=N1,N2,N3,...

	Enable Wake-on-LAN support for the relevant interface. Donald
	Becker's `ether-wake' application may be used to wake suspended
	machines.

	Also enables the NIC's power management support.

	global_enable_wol=N

	Sets enable_wol mode for all 3c59x NICs in the machine. Entries in
	the `enable_wol' array above will override any setting of this.

	Media selection
	---------------

	A number of the older NICs such as the 3c590 and 3c900 series have
	10base2 and AUI interfaces.

	Prior to January, 2001 this driver would autoeselect the 10base2 or AUI
	port if it didn't detect activity on the 10baseT port. It would then
	get stuck on the 10base2 port and a driver reload was necessary to
	switch back to 10baseT. This behaviour could not be prevented with a
	module option override.

	Later (current) versions of the driver _do_ support locking of the
	media type. So if you load the driver module with

	modprobe 3c59x options=0

	it will permanently select the 10baseT port. Automatic selection of
	other media types does not occur.


	Transmit error, Tx status register 82
	-------------------------------------

	This is a common error which is almost always caused by another host on
	the same network being in full-duplex mode, while this host is in
	half-duplex mode. You need to find that other host and make it run in
	half-duplex mode or fix this host to run in full-duplex mode.

	As a last resort, you can force the 3c59x driver into full-duplex mode
	with

	options 3c59x full_duplex=1

	but this has to be viewed as a workaround for broken network gear and
	should only really be used for equipment which cannot autonegotiate.


	Additional resources
	--------------------

	Details of the device driver implementation are at the top of the source file.

	Additional documentation is available at Don Becker's Linux Drivers site:

	http://www.scyld.com/vortex.html

	Donald Becker's driver development site:

	http://www.scyld.com/network.html

	Donald's vortex-diag program is useful for inspecting the NIC's state:

	http://www.scyld.com/ethercard_diag.html

	Donald's mii-diag program may be used for inspecting and manipulating
	the NIC's Media Independent Interface subsystem:

	http://www.scyld.com/ethercard_diag.html#mii-diag

	Donald's wake-on-LAN page:

	http://www.scyld.com/wakeonlan.html

	3Com's DOS-based application for setting up the NICs EEPROMs:

	ftp://ftp.3com.com/pub/nic/3c90x/3c90xx2.exe


	Autonegotiation notes
	---------------------

	The driver uses a one-minute heartbeat for adapting to changes in
	the external LAN environment if link is up and 5 seconds if link is down.
	This means that when, for example, a machine is unplugged from a hubbed
	10baseT LAN plugged into a switched 100baseT LAN, the throughput
	will be quite dreadful for up to sixty seconds. Be patient.

	Cisco interoperability note from Walter Wong <wcw+@CMU.EDU>:

	On a side note, adding HAS_NWAY seems to share a problem with the
	Cisco 6509 switch. Specifically, you need to change the spanning
	tree parameter for the port the machine is plugged into to 'portfast'
	mode. Otherwise, the negotiation fails. This has been an issue
	we've noticed for a while but haven't had the time to track down.

	Cisco switches (Jeff Busch <jbusch@deja.com>)

	My "standard config" for ports to which PC's/servers connect directly:

	interface FastEthernet0/N
	description machinename
	load-interval 30
	spanning-tree portfast

	If autonegotiation is a problem, you may need to specify "speed
	100" and "duplex full" as well (or "speed 10" and "duplex half").

	WARNING: DO NOT hook up hubs/switches/bridges to these
	specially-configured ports! The switch will become very confused.


	Reporting and diagnosing problems
	---------------------------------

	Maintainers find that accurate and complete problem reports are
	invaluable in resolving driver problems. We are frequently not able to
	reproduce problems and must rely on your patience and efforts to get to
	the bottom of the problem.

	If you believe you have a driver problem here are some of the
	steps you should take:

	- Is it really a driver problem?

	Eliminate some variables: try different cards, different
	computers, different cables, different ports on the switch/hub,
	different versions of the kernel or of the driver, etc.

	- OK, it's a driver problem.

	You need to generate a report. Typically this is an email to the
	maintainer and/or netdev@vger.kernel.org. The maintainer's
	email address will be in the driver source or in the MAINTAINERS file.

	- The contents of your report will vary a lot depending upon the
	problem. If it's a kernel crash then you should refer to the
	REPORTING-BUGS file.

	But for most problems it is useful to provide the following:

	o Kernel version, driver version

	o A copy of the banner message which the driver generates when
	it is initialised. For example:

	eth0: 3Com PCI 3c905C Tornado at 0xa400, 00:50:da:6a:88:f0, IRQ 19
	8K byte-wide RAM 5:3 Rx:Tx split, autoselect/Autonegotiate interface.
	MII transceiver found at address 24, status 782d.
	Enabling bus-master transmits and whole-frame receives.

	NOTE: You must provide the `debug=2' modprobe option to generate
	a full detection message. Please do this:

	modprobe 3c59x debug=2

	o If it is a PCI device, the relevant output from 'lspci -vx', eg:

	00:09.0 Ethernet controller: 3Com Corporation 3c905C-TX [Fast Etherlink] (rev 74)
	Subsystem: 3Com Corporation: Unknown device 9200
	Flags: bus master, medium devsel, latency 32, IRQ 19
	I/O ports at a400 [size=128]
	Memory at db000000 (32-bit, non-prefetchable) [size=128]
	Expansion ROM at <unassigned> [disabled] [size=128K]
	Capabilities: [dc] Power Management version 2
	00: b7 10 00 92 07 00 10 02 74 00 00 02 08 20 00 00
	10: 01 a4 00 00 00 00 00 db 00 00 00 00 00 00 00 00
	20: 00 00 00 00 00 00 00 00 00 00 00 00 b7 10 00 10
	30: 00 00 00 00 dc 00 00 00 00 00 00 00 05 01 0a 0a

	o A description of the environment: 10baseT? 100baseT?
	full/half duplex? switched or hubbed?

	o Any additional module parameters which you may be providing to the driver.

	o Any kernel logs which are produced. The more the merrier.
	If this is a large file and you are sending your report to a
	mailing list, mention that you have the logfile, but don't send
	it. If you're reporting direct to the maintainer then just send
	it.

	To ensure that all kernel logs are available, add the
	following line to /etc/syslog.conf:

	kern.* /var/log/messages

	Then restart syslogd with:

	/etc/rc.d/init.d/syslog restart

	(The above may vary, depending upon which Linux distribution you use).

	o If your problem is reproducible then that's great. Try the
	following:

	1) Increase the debug level. Usually this is done via:

	a) modprobe driver debug=7
	b) In /etc/modprobe.d/driver.conf:
	options driver debug=7

	2) Recreate the problem with the higher debug level,
	send all logs to the maintainer.

	3) Download you card's diagnostic tool from Donald
	Becker's website <http://www.scyld.com/ethercard_diag.html>.
	Download mii-diag.c as well. Build these.

	a) Run 'vortex-diag -aaee' and 'mii-diag -v' when the card is
	working correctly. Save the output.

	b) Run the above commands when the card is malfunctioning. Send
	both sets of output.

	Finally, please be patient and be prepared to do some work. You may
	end up working on this problem for a week or more as the maintainer
	asks more questions, asks for more tests, asks for patches to be
	applied, etc. At the end of it all, the problem may even remain
	unresolved.