device_drivers/cable/sb1000.rst

1 .. SPDX-License-Identifier: GPL-2.0
7 sb1000 is a module network device driver for the General Instrument (also known
10 It's a one-way downstream-only cable modem, meaning that your upstream net link
19 Support for this device is now a part of the standard Linux kernel.  The
23 1. The "cmconfig" program.  This is a utility which supplements "ifconfig"
24    to configure the cable modem and network interface (usually called "cm0");
34    the sb1000 driver can be found at:
36       - http://web.archive.org/web/%2E/http://home.adelphia.net/~siglercm/sb1000.html
37       - http://web.archive.org/web/%2E/http://linuxpower.cx/~cable/
41 3. The standard isapnp tools.  These are necessary to configure your SB1000
50    isapnp, pnpdump, or /etc/isapnp.conf, go to:
54 Using the driver
57 To make the SB1000 card work, follow these steps:
60    you prefer, in the top kernel tree directory to set up your kernel
62    and to say "M" to the sb1000 driver.  Also say "Y" or "M" to all the standard
65 2. **BEFORE** you build the kernel, edit drivers/net/sb1000.c.  Make sure
66    to redefine the value of READ_DATA_PORT to match the I/O address used
67    by isapnp to access your PnP cards.  This is the value of READPORT in
68    /etc/isapnp.conf or given by the output of pnpdump.
70 3. Build and install the kernel and modules as usual.
72 4. Boot your new kernel following the usual procedures.
74 5. Set up to configure the new SB1000 PnP card by capturing the output
75    of "pnpdump" to a file and editing this file to set the correct I/O ports,
76    IRQ, and DMA settings for all your PnP cards.  Make sure none of the settings
77    conflict with one another.  Then test this configuration by running the
78    "isapnp" command with your new config file as the input.  Check for
81    Then save the finished config file as /etc/isapnp.conf for proper
82    configuration on subsequent reboots.
84 6. Download the original file sb1000-1.1.2.tar.gz from Franco's site or one of
85    the others referenced above.  As root, unpack it into a temporary directory
86    and do a ``make cmconfig`` and then ``install -c cmconfig /usr/local/sbin``.
87    Don't do ``make install`` because it expects to find all the utilities built
90 7. As root, copy all the files under the ppp/ subdirectory in Franco's
92    already in there.  Then modify ppp@gi-on to set the correct login name,
93    phone number, and frequency for the cable modem.  Also edit pap-secrets
94    to specify your login name and password and any site-specific information
98    the older ipfwadm commands from the 2.0.x kernels.  There's a neat utility to
103    You may also wish to modify the firewall script to implement a different
106 9. Start the PPP connection via the script /etc/ppp/ppp@gi-on.  You must be
109    connect successfully the cable modem interface will come up and you'll see a
110    driver message like this at the console::
115    The "ifconfig" command should show two new interfaces, ppp0 and cm0.
117    The command "cmconfig cm0" will give you information about the cable modem
120 10. Try pinging a site via ``ping -c 5 www.yahoo.com``, for example.  You should
125     has no syntax errors and has the right nameserver IP addresses in it.
126     If this doesn't help, try something like ``ping -c 5 204.71.200.67`` to
127     see if the networking is running but the DNS resolution is where the
130 12. If you still have problems, go to the support web sites mentioned above
131     and read the information and documentation there.
136 1. Packets go out on the ppp0 interface but don't come back on the cm0
138    numerical IP addresses.  (This happens predominantly on Debian systems due
139    to a default boot-time configuration script.)
143    can share the same IP address as the ppp0 interface.  Note that this
144    command should probably be added to the /etc/ppp/cablemodem script
145    *right*between* the "/sbin/ifconfig" and "/sbin/cmconfig" commands.
147    If you do this to /proc/sys/net/ipv4/conf/default/rp_filter on each reboot
148    (in rc.local or some such) then any interfaces can share the same IP
151 2. I get "unresolved symbol" error messages on executing ``insmod sb1000.o``.
154    You probably have a non-matching kernel source tree and
156    install the correct versions of the header files in these two directories.
157    Then rebuild and reinstall the kernel.
162    There's a problem with later versions of isapnp using the "(CHECK)"
163    option in the lines that allocate the two I/O addresses for the SB1000 card.
164    This first popped up on RH 6.0.  Delete "(CHECK)" for the SB1000 I/O addresses.
166    rerun isapnp and go from there.
168 4. I can't execute the /etc/ppp/ppp@gi-on file.
171    As root do ``chmod ug+x /etc/ppp/ppp@gi-on``.
173 5. The firewall script isn't working (with 2.2.x and higher kernels).
176    Use the ipfwadm2ipchains script referenced above to convert the
177    /etc/ppp/firewall script from the deprecated ipfwadm commands to ipchains.
179 6. I'm getting *tons* of firewall deny messages in the /var/kern.log,
185    and/or portscanning (UDP connection attempts) attacks!  Look over the deny
186    messages to figure out what the attack is and where it's coming from.  Next,
187    edit /etc/ppp/cablemodem and make sure the ",nobroadcast" option is turned on
188    to the "cmconfig" command (uncomment that line).  If you're not receiving these
189    denied packets on your broadcast interface (IP address xxx.yyy.zzz.255
194    (and typically during a lengthy download through the cable modem)!
197    You may need to add a short delay in the driver to 'slow down' the
198    SURFboard because your PC might not be able to keep up with the transfer rate
199    of the SB1000. To do this, it's probably best to download Franco's
200    sb1000-1.1.2.tar.gz archive and build and install sb1000.o manually.  You'll
201    want to edit the 'Makefile' and look for the 'SB1000_DELAY'
202    define.  Uncomment those 'CFLAGS' lines (and comment out the default ones)
203    and try setting the delay to something like 60 microseconds with:
204    '-DSB1000_DELAY=60'.  Then do ``make`` and as root ``make install`` and try
205    it out.  If it still doesn't work or you like playing with the driver, you may
206    try other numbers.  Remember though that the higher the delay, the slower the
207    driver (which slows down the rest of the PC too when it is actively
216 and Ralph Bonnell who are now managing the Linux SB1000 web site, and to
217 the SB1000 users who reported and helped debug the common problems listed