From beb116954b9b7f3bb56412b2494b562f02b864b1 Mon Sep 17 00:00:00 2001 From: Ralf Baechle Date: Tue, 7 Jan 1997 02:33:00 +0000 Subject: Import of Linux/MIPS 2.1.14 --- drivers/scsi/README.qlogicfas | 73 +++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 73 insertions(+) create mode 100644 drivers/scsi/README.qlogicfas (limited to 'drivers/scsi/README.qlogicfas') diff --git a/drivers/scsi/README.qlogicfas b/drivers/scsi/README.qlogicfas new file mode 100644 index 000000000..737a03fe7 --- /dev/null +++ b/drivers/scsi/README.qlogicfas @@ -0,0 +1,73 @@ + +RANDOM NOTES ON THE QLOGICFAS SCSI DRIVER + +This driver supports the Qlogic FASXXX family of chips. This driver +only works with the ISA, VLB, and PCMCIA versions of the Qlogic +FastSCSI! cards as well as any other card based on the FASXX chip +(including the Control Concepts SCSI/IDE/SIO/PIO/FDC cards). + +This driver does NOT support the PCI version. Support for these PCI +Qlogic boards: + + IQ-PCI + IQ-PCI-10 + IQ-PCI-D + +is provided by the qlogicisp.c driver. Check README.qlogicisp for details. + +PCMCIA SUPPORT + +This currently only works if the card is enabled first from DOS. This means +you will have to load your socket and card services, and QL41DOS.SYS and +QL40ENBL.SYS. These are a minimum, but loading the rest of the modules +won't interfere with the operation. The next thing to do is load the kernel +without resetting the hardware, which can be a simple ctrl-alt-delete with +a boot floppy, or by using loadlin with the kernel image accessible from +DOS. If you are using the Linux PCMCIA driver, you will have to adjust +it or otherwise stop it from configuring the card. + +I am working with the PCMCIA group to make it more flexible, but that may +take a while. + +ALL CARDS + +The top of the qlogic.c file has a number of defines that controls +configuration. As shipped, it provides a balance between speed and +function. If there are any problems, try setting SLOW_CABLE to 1, and +then try changing USE_IRQ and TURBO_PDMA to zero. If you are familiar +with SCSI, there are other settings which can tune the bus. + +It may be a good idea to enable RESET_AT_START, especially if the devices +may not have been just powered up, or if you are restarting after a crash, +since they may be busy trying to complete the last command or something. +It comes up faster if this is set to zero, and if you have reliable +hardware and connections it may be more useful to not reset things. + +SOME TROUBLESHOOTING TIPS + +Make sure it works properly under DOS. You should also do an initial FDISK +on a new drive if you want partitions. + +Don't enable all the speedups first. If anything is wrong, they will make +any problem worse. + +IMPORTANT + +The best way to test if your cables, termination, etc. are good is to copy +a very big file (e.g. a doublespace container file, or a very large executable +or archive). It should be at least 5 megabytes, but you can do multiple tests +on smaller files. Then do a COMP to verify that the file copied properly. +(Turn off all caching when doing these tests, otherwise you will test your +RAM and not the files). Then do 10 COMPs, comparing the same file on the +SCSI hard drive, i.e. "COMP realbig.doc realbig.doc". Then do it after the +computer gets warm. + +I noticed my system which seems to work 100% would fail this test if the +computer was left on for a few hours. It was worse with longer cables, and +more devices on the SCSI bus. What seems to happen is that it gets a false +ACK causing an extra byte to be inserted into the stream (and this is not +detected). This can be caused by bad termination (the ACK can be reflected), +or by noise when the chips work less well because of the heat, or when cables +get too long for the speed. + +Remember, if it doesn't work under DOS, it probably won't work under Linux. -- cgit v1.2.3