0001 .. SPDX-License-Identifier: GPL-2.0
0002
0003 ===================
0004 SB100 device driver
0005 ===================
0006
0007 sb1000 is a module network device driver for the General Instrument (also known
0008 as NextLevel) SURFboard1000 internal cable modem board. This is an ISA card
0009 which is used by a number of cable TV companies to provide cable modem access.
0010 It's a one-way downstream-only cable modem, meaning that your upstream net link
0011 is provided by your regular phone modem.
0012
0013 This driver was written by Franco Venturi <fventuri@mediaone.net>. He deserves
0014 a great deal of thanks for this wonderful piece of code!
0015
0016 Needed tools
0017 ============
0018
0019 Support for this device is now a part of the standard Linux kernel. The
0020 driver source code file is drivers/net/sb1000.c. In addition to this
0021 you will need:
0022
0023 1. The "cmconfig" program. This is a utility which supplements "ifconfig"
0024 to configure the cable modem and network interface (usually called "cm0");
0025
0026 2. Several PPP scripts which live in /etc/ppp to make connecting via your
0027 cable modem easy.
0028
0029 These utilities can be obtained from:
0030
0031 http://www.jacksonville.net/~fventuri/
0032
0033 in Franco's original source code distribution .tar.gz file. Support for
0034 the sb1000 driver can be found at:
0035
0036 - http://web.archive.org/web/%2E/http://home.adelphia.net/~siglercm/sb1000.html
0037 - http://web.archive.org/web/%2E/http://linuxpower.cx/~cable/
0038
0039 along with these utilities.
0040
0041 3. The standard isapnp tools. These are necessary to configure your SB1000
0042 card at boot time (or afterwards by hand) since it's a PnP card.
0043
0044 If you don't have these installed as a standard part of your Linux
0045 distribution, you can find them at:
0046
0047 http://www.roestock.demon.co.uk/isapnptools/
0048
0049 or check your Linux distribution binary CD or their web site. For help with
0050 isapnp, pnpdump, or /etc/isapnp.conf, go to:
0051
0052 http://www.roestock.demon.co.uk/isapnptools/isapnpfaq.html
0053
0054 Using the driver
0055 ================
0056
0057 To make the SB1000 card work, follow these steps:
0058
0059 1. Run ``make config``, or ``make menuconfig``, or ``make xconfig``, whichever
0060 you prefer, in the top kernel tree directory to set up your kernel
0061 configuration. Make sure to say "Y" to "Prompt for development drivers"
0062 and to say "M" to the sb1000 driver. Also say "Y" or "M" to all the standard
0063 networking questions to get TCP/IP and PPP networking support.
0064
0065 2. **BEFORE** you build the kernel, edit drivers/net/sb1000.c. Make sure
0066 to redefine the value of READ_DATA_PORT to match the I/O address used
0067 by isapnp to access your PnP cards. This is the value of READPORT in
0068 /etc/isapnp.conf or given by the output of pnpdump.
0069
0070 3. Build and install the kernel and modules as usual.
0071
0072 4. Boot your new kernel following the usual procedures.
0073
0074 5. Set up to configure the new SB1000 PnP card by capturing the output
0075 of "pnpdump" to a file and editing this file to set the correct I/O ports,
0076 IRQ, and DMA settings for all your PnP cards. Make sure none of the settings
0077 conflict with one another. Then test this configuration by running the
0078 "isapnp" command with your new config file as the input. Check for
0079 errors and fix as necessary. (As an aside, I use I/O ports 0x110 and
0080 0x310 and IRQ 11 for my SB1000 card and these work well for me. YMMV.)
0081 Then save the finished config file as /etc/isapnp.conf for proper
0082 configuration on subsequent reboots.
0083
0084 6. Download the original file sb1000-1.1.2.tar.gz from Franco's site or one of
0085 the others referenced above. As root, unpack it into a temporary directory
0086 and do a ``make cmconfig`` and then ``install -c cmconfig /usr/local/sbin``.
0087 Don't do ``make install`` because it expects to find all the utilities built
0088 and ready for installation, not just cmconfig.
0089
0090 7. As root, copy all the files under the ppp/ subdirectory in Franco's
0091 tar file into /etc/ppp, being careful not to overwrite any files that are
0092 already in there. Then modify ppp@gi-on to set the correct login name,
0093 phone number, and frequency for the cable modem. Also edit pap-secrets
0094 to specify your login name and password and any site-specific information
0095 you need.
0096
0097 8. Be sure to modify /etc/ppp/firewall to use ipchains instead of
0098 the older ipfwadm commands from the 2.0.x kernels. There's a neat utility to
0099 convert ipfwadm commands to ipchains commands:
0100
0101 http://users.dhp.com/~whisper/ipfwadm2ipchains/
0102
0103 You may also wish to modify the firewall script to implement a different
0104 firewalling scheme.
0105
0106 9. Start the PPP connection via the script /etc/ppp/ppp@gi-on. You must be
0107 root to do this. It's better to use a utility like sudo to execute
0108 frequently used commands like this with root permissions if possible. If you
0109 connect successfully the cable modem interface will come up and you'll see a
0110 driver message like this at the console::
0111
0112 cm0: sb1000 at (0x110,0x310), csn 1, S/N 0x2a0d16d8, IRQ 11.
0113 sb1000.c:v1.1.2 6/01/98 (fventuri@mediaone.net)
0114
0115 The "ifconfig" command should show two new interfaces, ppp0 and cm0.
0116
0117 The command "cmconfig cm0" will give you information about the cable modem
0118 interface.
0119
0120 10. Try pinging a site via ``ping -c 5 www.yahoo.com``, for example. You should
0121 see packets received.
0122
0123 11. If you can't get site names (like www.yahoo.com) to resolve into
0124 IP addresses (like 204.71.200.67), be sure your /etc/resolv.conf file
0125 has no syntax errors and has the right nameserver IP addresses in it.
0126 If this doesn't help, try something like ``ping -c 5 204.71.200.67`` to
0127 see if the networking is running but the DNS resolution is where the
0128 problem lies.
0129
0130 12. If you still have problems, go to the support web sites mentioned above
0131 and read the information and documentation there.
0132
0133 Common problems
0134 ===============
0135
0136 1. Packets go out on the ppp0 interface but don't come back on the cm0
0137 interface. It looks like I'm connected but I can't even ping any
0138 numerical IP addresses. (This happens predominantly on Debian systems due
0139 to a default boot-time configuration script.)
0140
0141 Solution
0142 As root ``echo 0 > /proc/sys/net/ipv4/conf/cm0/rp_filter`` so it
0143 can share the same IP address as the ppp0 interface. Note that this
0144 command should probably be added to the /etc/ppp/cablemodem script
0145 *right*between* the "/sbin/ifconfig" and "/sbin/cmconfig" commands.
0146 You may need to do this to /proc/sys/net/ipv4/conf/ppp0/rp_filter as well.
0147 If you do this to /proc/sys/net/ipv4/conf/default/rp_filter on each reboot
0148 (in rc.local or some such) then any interfaces can share the same IP
0149 addresses.
0150
0151 2. I get "unresolved symbol" error messages on executing ``insmod sb1000.o``.
0152
0153 Solution
0154 You probably have a non-matching kernel source tree and
0155 /usr/include/linux and /usr/include/asm header files. Make sure you
0156 install the correct versions of the header files in these two directories.
0157 Then rebuild and reinstall the kernel.
0158
0159 3. When isapnp runs it reports an error, and my SB1000 card isn't working.
0160
0161 Solution
0162 There's a problem with later versions of isapnp using the "(CHECK)"
0163 option in the lines that allocate the two I/O addresses for the SB1000 card.
0164 This first popped up on RH 6.0. Delete "(CHECK)" for the SB1000 I/O addresses.
0165 Make sure they don't conflict with any other pieces of hardware first! Then
0166 rerun isapnp and go from there.
0167
0168 4. I can't execute the /etc/ppp/ppp@gi-on file.
0169
0170 Solution
0171 As root do ``chmod ug+x /etc/ppp/ppp@gi-on``.
0172
0173 5. The firewall script isn't working (with 2.2.x and higher kernels).
0174
0175 Solution
0176 Use the ipfwadm2ipchains script referenced above to convert the
0177 /etc/ppp/firewall script from the deprecated ipfwadm commands to ipchains.
0178
0179 6. I'm getting *tons* of firewall deny messages in the /var/kern.log,
0180 /var/messages, and/or /var/syslog files, and they're filling up my /var
0181 partition!!!
0182
0183 Solution
0184 First, tell your ISP that you're receiving DoS (Denial of Service)
0185 and/or portscanning (UDP connection attempts) attacks! Look over the deny
0186 messages to figure out what the attack is and where it's coming from. Next,
0187 edit /etc/ppp/cablemodem and make sure the ",nobroadcast" option is turned on
0188 to the "cmconfig" command (uncomment that line). If you're not receiving these
0189 denied packets on your broadcast interface (IP address xxx.yyy.zzz.255
0190 typically), then someone is attacking your machine in particular. Be careful
0191 out there....
0192
0193 7. Everything seems to work fine but my computer locks up after a while
0194 (and typically during a lengthy download through the cable modem)!
0195
0196 Solution
0197 You may need to add a short delay in the driver to 'slow down' the
0198 SURFboard because your PC might not be able to keep up with the transfer rate
0199 of the SB1000. To do this, it's probably best to download Franco's
0200 sb1000-1.1.2.tar.gz archive and build and install sb1000.o manually. You'll
0201 want to edit the 'Makefile' and look for the 'SB1000_DELAY'
0202 define. Uncomment those 'CFLAGS' lines (and comment out the default ones)
0203 and try setting the delay to something like 60 microseconds with:
0204 '-DSB1000_DELAY=60'. Then do ``make`` and as root ``make install`` and try
0205 it out. If it still doesn't work or you like playing with the driver, you may
0206 try other numbers. Remember though that the higher the delay, the slower the
0207 driver (which slows down the rest of the PC too when it is actively
0208 used). Thanks to Ed Daiga for this tip!
0209
0210 Credits
0211 =======
0212
0213 This README came from Franco Venturi's original README file which is
0214 still supplied with his driver .tar.gz archive. I and all other sb1000 users
0215 owe Franco a tremendous "Thank you!" Additional thanks goes to Carl Patten
0216 and Ralph Bonnell who are now managing the Linux SB1000 web site, and to
0217 the SB1000 users who reported and helped debug the common problems listed
0218 above.
0219
0220
0221 Clemmitt Sigler
0222 csigler@vt.edu
