linux/Documentation/scsi/qlogicfas.txt
<<
>>
Prefs
   1
   2This driver supports the Qlogic FASXXX family of chips.  This driver
   3only works with the ISA, VLB, and PCMCIA versions of the Qlogic
   4FastSCSI!  cards as well as any other card based on the FASXX chip
   5(including the Control Concepts SCSI/IDE/SIO/PIO/FDC cards).
   6
   7This driver does NOT support the PCI version.  Support for these PCI
   8Qlogic boards:
   9
  10        * IQ-PCI
  11        * IQ-PCI-10
  12        * IQ-PCI-D
  13
  14is provided by the qla1280 driver.
  15
  16Nor does it support the PCI-Basic, which is supported by the
  17'am53c974' driver.
  18
  19PCMCIA SUPPORT
  20
  21This currently only works if the card is enabled first from DOS.  This
  22means you will have to load your socket and card services, and
  23QL41DOS.SYS and QL40ENBL.SYS.  These are a minimum, but loading the
  24rest of the modules won't interfere with the operation.  The next
  25thing to do is load the kernel without resetting the hardware, which
  26can be a simple ctrl-alt-delete with a boot floppy, or by using
  27loadlin with the kernel image accessible from DOS.  If you are using
  28the Linux PCMCIA driver, you will have to adjust it or otherwise stop
  29it from configuring the card.
  30
  31I am working with the PCMCIA group to make it more flexible, but that
  32may take a while.
  33
  34ALL CARDS
  35
  36The top of the qlogic.c file has a number of defines that controls
  37configuration.  As shipped, it provides a balance between speed and
  38function.  If there are any problems, try setting SLOW_CABLE to 1, and
  39then try changing USE_IRQ and TURBO_PDMA to zero.  If you are familiar
  40with SCSI, there are other settings which can tune the bus.
  41
  42It may be a good idea to enable RESET_AT_START, especially if the
  43devices may not have been just powered up, or if you are restarting
  44after a crash, since they may be busy trying to complete the last
  45command or something.  It comes up faster if this is set to zero, and
  46if you have reliable hardware and connections it may be more useful to
  47not reset things.
  48
  49SOME TROUBLESHOOTING TIPS
  50
  51Make sure it works properly under DOS.  You should also do an initial FDISK
  52on a new drive if you want partitions.
  53
  54Don't enable all the speedups first.  If anything is wrong, they will make
  55any problem worse.
  56
  57IMPORTANT
  58
  59The best way to test if your cables, termination, etc. are good is to
  60copy a very big file (e.g. a doublespace container file, or a very
  61large executable or archive).  It should be at least 5 megabytes, but
  62you can do multiple tests on smaller files.  Then do a COMP to verify
  63that the file copied properly.  (Turn off all caching when doing these
  64tests, otherwise you will test your RAM and not the files).  Then do
  6510 COMPs, comparing the same file on the SCSI hard drive, i.e. "COMP
  66realbig.doc realbig.doc".  Then do it after the computer gets warm.
  67
  68I noticed my system which seems to work 100% would fail this test if
  69the computer was left on for a few hours.  It was worse with longer
  70cables, and more devices on the SCSI bus.  What seems to happen is
  71that it gets a false ACK causing an extra byte to be inserted into the
  72stream (and this is not detected).  This can be caused by bad
  73termination (the ACK can be reflected), or by noise when the chips
  74work less well because of the heat, or when cables get too long for
  75the speed.
  76
  77Remember, if it doesn't work under DOS, it probably won't work under
  78Linux.
  79
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.