1.. SPDX-License-Identifier: GPL-2.0
2
3=================================
4Qlogic FASXXX Family Driver Notes
5=================================
6
7This driver supports the Qlogic FASXXX family of chips.  This driver
8only works with the ISA, VLB, and PCMCIA versions of the Qlogic
9FastSCSI!  cards as well as any other card based on the FASXX chip
10(including the Control Concepts SCSI/IDE/SIO/PIO/FDC cards).
11
12This driver does NOT support the PCI version.  Support for these PCI
13Qlogic boards:
14
15	* IQ-PCI
16	* IQ-PCI-10
17	* IQ-PCI-D
18
19is provided by the qla1280 driver.
20
21Nor does it support the PCI-Basic, which is supported by the
22'am53c974' driver.
23
24PCMCIA Support
25==============
26
27This currently only works if the card is enabled first from DOS.  This
28means you will have to load your socket and card services, and
29QL41DOS.SYS and QL40ENBL.SYS.  These are a minimum, but loading the
30rest of the modules won't interfere with the operation.  The next
31thing to do is load the kernel without resetting the hardware, which
32can be a simple ctrl-alt-delete with a boot floppy, or by using
33loadlin with the kernel image accessible from DOS.  If you are using
34the Linux PCMCIA driver, you will have to adjust it or otherwise stop
35it from configuring the card.
36
37I am working with the PCMCIA group to make it more flexible, but that
38may take a while.
39
40All Cards
41=========
42
43The top of the qlogic.c file has a number of defines that controls
44configuration.  As shipped, it provides a balance between speed and
45function.  If there are any problems, try setting SLOW_CABLE to 1, and
46then try changing USE_IRQ and TURBO_PDMA to zero.  If you are familiar
47with SCSI, there are other settings which can tune the bus.
48
49It may be a good idea to enable RESET_AT_START, especially if the
50devices may not have been just powered up, or if you are restarting
51after a crash, since they may be busy trying to complete the last
52command or something.  It comes up faster if this is set to zero, and
53if you have reliable hardware and connections it may be more useful to
54not reset things.
55
56Some Troubleshooting Tips
57=========================
58
59Make sure it works properly under DOS.  You should also do an initial FDISK
60on a new drive if you want partitions.
61
62Don't enable all the speedups first.  If anything is wrong, they will make
63any problem worse.
64
65Important
66=========
67
68The best way to test if your cables, termination, etc. are good is to
69copy a very big file (e.g. a doublespace container file, or a very
70large executable or archive).  It should be at least 5 megabytes, but
71you can do multiple tests on smaller files.  Then do a COMP to verify
72that the file copied properly.  (Turn off all caching when doing these
73tests, otherwise you will test your RAM and not the files).  Then do
7410 COMPs, comparing the same file on the SCSI hard drive, i.e. "COMP
75realbig.doc realbig.doc".  Then do it after the computer gets warm.
76
77I noticed my system which seems to work 100% would fail this test if
78the computer was left on for a few hours.  It was worse with longer
79cables, and more devices on the SCSI bus.  What seems to happen is
80that it gets a false ACK causing an extra byte to be inserted into the
81stream (and this is not detected).  This can be caused by bad
82termination (the ACK can be reflected), or by noise when the chips
83work less well because of the heat, or when cables get too long for
84the speed.
85
86Remember, if it doesn't work under DOS, it probably won't work under
87Linux.
88