diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /Documentation/scsi/qlogicfas.txt |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'Documentation/scsi/qlogicfas.txt')
-rw-r--r-- | Documentation/scsi/qlogicfas.txt | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/Documentation/scsi/qlogicfas.txt b/Documentation/scsi/qlogicfas.txt new file mode 100644 index 000000000000..398f99168077 --- /dev/null +++ b/Documentation/scsi/qlogicfas.txt | |||
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1 | |||
2 | This driver supports the Qlogic FASXXX family of chips. This driver | ||
3 | only works with the ISA, VLB, and PCMCIA versions of the Qlogic | ||
4 | FastSCSI! cards as well as any other card based on the FASXX chip | ||
5 | (including the Control Concepts SCSI/IDE/SIO/PIO/FDC cards). | ||
6 | |||
7 | This driver does NOT support the PCI version. Support for these PCI | ||
8 | Qlogic boards: | ||
9 | |||
10 | * IQ-PCI | ||
11 | * IQ-PCI-10 | ||
12 | * IQ-PCI-D | ||
13 | |||
14 | is provided by the qlogicisp.c driver. Check README.qlogicisp for | ||
15 | details. | ||
16 | |||
17 | Nor does it support the PCI-Basic, which is supported by the | ||
18 | 'am53c974' driver. | ||
19 | |||
20 | PCMCIA SUPPORT | ||
21 | |||
22 | This currently only works if the card is enabled first from DOS. This | ||
23 | means you will have to load your socket and card services, and | ||
24 | QL41DOS.SYS and QL40ENBL.SYS. These are a minimum, but loading the | ||
25 | rest of the modules won't interfere with the operation. The next | ||
26 | thing to do is load the kernel without resetting the hardware, which | ||
27 | can be a simple ctrl-alt-delete with a boot floppy, or by using | ||
28 | loadlin with the kernel image accessible from DOS. If you are using | ||
29 | the Linux PCMCIA driver, you will have to adjust it or otherwise stop | ||
30 | it from configuring the card. | ||
31 | |||
32 | I am working with the PCMCIA group to make it more flexible, but that | ||
33 | may take a while. | ||
34 | |||
35 | ALL CARDS | ||
36 | |||
37 | The top of the qlogic.c file has a number of defines that controls | ||
38 | configuration. As shipped, it provides a balance between speed and | ||
39 | function. If there are any problems, try setting SLOW_CABLE to 1, and | ||
40 | then try changing USE_IRQ and TURBO_PDMA to zero. If you are familiar | ||
41 | with SCSI, there are other settings which can tune the bus. | ||
42 | |||
43 | It may be a good idea to enable RESET_AT_START, especially if the | ||
44 | devices may not have been just powered up, or if you are restarting | ||
45 | after a crash, since they may be busy trying to complete the last | ||
46 | command or something. It comes up faster if this is set to zero, and | ||
47 | if you have reliable hardware and connections it may be more useful to | ||
48 | not reset things. | ||
49 | |||
50 | SOME TROUBLESHOOTING TIPS | ||
51 | |||
52 | Make sure it works properly under DOS. You should also do an initial FDISK | ||
53 | on a new drive if you want partitions. | ||
54 | |||
55 | Don't enable all the speedups first. If anything is wrong, they will make | ||
56 | any problem worse. | ||
57 | |||
58 | IMPORTANT | ||
59 | |||
60 | The best way to test if your cables, termination, etc. are good is to | ||
61 | copy a very big file (e.g. a doublespace container file, or a very | ||
62 | large executable or archive). It should be at least 5 megabytes, but | ||
63 | you can do multiple tests on smaller files. Then do a COMP to verify | ||
64 | that the file copied properly. (Turn off all caching when doing these | ||
65 | tests, otherwise you will test your RAM and not the files). Then do | ||
66 | 10 COMPs, comparing the same file on the SCSI hard drive, i.e. "COMP | ||
67 | realbig.doc realbig.doc". Then do it after the computer gets warm. | ||
68 | |||
69 | I noticed my system which seems to work 100% would fail this test if | ||
70 | the computer was left on for a few hours. It was worse with longer | ||
71 | cables, and more devices on the SCSI bus. What seems to happen is | ||
72 | that it gets a false ACK causing an extra byte to be inserted into the | ||
73 | stream (and this is not detected). This can be caused by bad | ||
74 | termination (the ACK can be reflected), or by noise when the chips | ||
75 | work less well because of the heat, or when cables get too long for | ||
76 | the speed. | ||
77 | |||
78 | Remember, if it doesn't work under DOS, it probably won't work under | ||
79 | Linux. | ||