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+This file describes the floppy driver.
+
+FAQ list:
+=========
+
+ A FAQ list may be found in the fdutils package (see below), and also
+at <http://fdutils.linux.lu/faq.html>.
+
+
+LILO configuration options (Thinkpad users, read this)
+======================================================
+
+ The floppy driver is configured using the 'floppy=' option in
+lilo. This option can be typed at the boot prompt, or entered in the
+lilo configuration file.
+
+ Example: If your kernel is called linux-2.6.9, type the following line
+at the lilo boot prompt (if you have a thinkpad):
+
+ linux-2.6.9 floppy=thinkpad
+
+You may also enter the following line in /etc/lilo.conf, in the description
+of linux-2.6.9:
+
+ append = "floppy=thinkpad"
+
+ Several floppy related options may be given, example:
+
+ linux-2.6.9 floppy=daring floppy=two_fdc
+ append = "floppy=daring floppy=two_fdc"
+
+ If you give options both in the lilo config file and on the boot
+prompt, the option strings of both places are concatenated, the boot
+prompt options coming last. That's why there are also options to
+restore the default behavior.
+
+
+Module configuration options
+============================
+
+ If you use the floppy driver as a module, use the following syntax:
+modprobe floppy <options>
+
+Example:
+ modprobe floppy omnibook messages
+
+ If you need certain options enabled every time you load the floppy driver,
+you can put:
+
+ options floppy omnibook messages
+
+in /etc/modprobe.conf.
+
+
+ The floppy driver related options are:
+
+ floppy=asus_pci
+        Sets the bit mask to allow only units 0 and 1. (default)
+
+ floppy=daring
+        Tells the floppy driver that you have a well behaved floppy controller.
+        This allows more efficient and smoother operation, but may fail on
+        certain controllers. This may speed up certain operations.
+
+ floppy=0,daring
+        Tells the floppy driver that your floppy controller should be used
+        with caution.
+
+ floppy=one_fdc
+        Tells the floppy driver that you have only one floppy controller.
+        (default)
+
+ floppy=two_fdc
+ floppy=<address>,two_fdc
+        Tells the floppy driver that you have two floppy controllers.
+        The second floppy controller is assumed to be at <address>.
+        This option is not needed if the second controller is at address
+        0x370, and if you use the 'cmos' option.
+
+ floppy=thinkpad
+        Tells the floppy driver that you have a Thinkpad. Thinkpads use an
+        inverted convention for the disk change line.
+
+ floppy=0,thinkpad
+        Tells the floppy driver that you don't have a Thinkpad.
+
+ floppy=omnibook
+ floppy=nodma
+        Tells the floppy driver not to use Dma for data transfers.
+        This is needed on HP Omnibooks, which don't have a workable
+        DMA channel for the floppy driver. This option is also useful
+        if you frequently get "Unable to allocate DMA memory" messages.
+        Indeed, dma memory needs to be continuous in physical memory,
+        and is thus harder to find, whereas non-dma buffers may be
+        allocated in virtual memory. However, I advise against this if
+        you have an FDC without a FIFO (8272A or 82072). 82072A and
+        later are OK. You also need at least a 486 to use nodma.
+        If you use nodma mode, I suggest you also set the FIFO
+        threshold to 10 or lower, in order to limit the number of data
+        transfer interrupts.
+
+        If you have a FIFO-able FDC, the floppy driver automatically
+        falls back on non DMA mode if no DMA-able memory can be found.
+        If you want to avoid this, explicitly ask for 'yesdma'.
+
+ floppy=yesdma
+        Tells the floppy driver that a workable DMA channel is available.
+        (default)
+
+ floppy=nofifo
+        Disables the FIFO entirely. This is needed if you get "Bus
+        master arbitration error" messages from your Ethernet card (or
+        from other devices) while accessing the floppy.
+
+ floppy=usefifo
+        Enables the FIFO. (default)
+
+ floppy=<threshold>,fifo_depth
+        Sets the FIFO threshold. This is mostly relevant in DMA
+        mode. If this is higher, the floppy driver tolerates more
+        interrupt latency, but it triggers more interrupts (i.e. it
+        imposes more load on the rest of the system). If this is
+        lower, the interrupt latency should be lower too (faster
+        processor). The benefit of a lower threshold is less
+        interrupts.
+
+        To tune the fifo threshold, switch on over/underrun messages
+        using 'floppycontrol --messages'. Then access a floppy
+        disk. If you get a huge amount of "Over/Underrun - retrying"
+        messages, then the fifo threshold is too low. Try with a
+        higher value, until you only get an occasional Over/Underrun.
+        It is a good idea to compile the floppy driver as a module
+        when doing this tuning. Indeed, it allows to try different
+        fifo values without rebooting the machine for each test. Note
+        that you need to do 'floppycontrol --messages' every time you
+        re-insert the module.
+
+        Usually, tuning the fifo threshold should not be needed, as
+        the default (0xa) is reasonable.
+
+ floppy=<drive>,<type>,cmos
+        Sets the CMOS type of <drive> to <type>. This is mandatory if
+        you have more than two floppy drives (only two can be
+        described in the physical CMOS), or if your BIOS uses
+        non-standard CMOS types. The CMOS types are:
+
+                0 - Use the value of the physical CMOS
+                1 - 5 1/4 DD
+                2 - 5 1/4 HD
+                3 - 3 1/2 DD
+                4 - 3 1/2 HD
+                5 - 3 1/2 ED
+                6 - 3 1/2 ED
+               16 - unknown or not installed
+
+        (Note: there are two valid types for ED drives. This is because 5 was
+        initially chosen to represent floppy *tapes*, and 6 for ED drives.
+        AMI ignored this, and used 5 for ED drives. That's why the floppy
+        driver handles both.)
+
+ floppy=unexpected_interrupts
+        Print a warning message when an unexpected interrupt is received.
+        (default)
+
+ floppy=no_unexpected_interrupts
+ floppy=L40SX
+        Don't print a message when an unexpected interrupt is received. This
+        is needed on IBM L40SX laptops in certain video modes. (There seems
+        to be an interaction between video and floppy. The unexpected
+        interrupts affect only performance, and can be safely ignored.)
+
+ floppy=broken_dcl
+        Don't use the disk change line, but assume that the disk was
+        changed whenever the device node is reopened. Needed on some
+        boxes where the disk change line is broken or unsupported.
+        This should be regarded as a stopgap measure, indeed it makes
+        floppy operation less efficient due to unneeded cache
+        flushings, and slightly more unreliable. Please verify your
+        cable, connection and jumper settings if you have any DCL
+        problems. However, some older drives, and also some laptops
+        are known not to have a DCL.
+
+ floppy=debug
+        Print debugging messages.
+
+ floppy=messages
+        Print informational messages for some operations (disk change
+        notifications, warnings about over and underruns, and about
+        autodetection).
+
+ floppy=silent_dcl_clear
+        Uses a less noisy way to clear the disk change line (which
+        doesn't involve seeks). Implied by 'daring' option.
+
+ floppy=<nr>,irq
+        Sets the floppy IRQ to <nr> instead of 6.
+
+ floppy=<nr>,dma
+        Sets the floppy DMA channel to <nr> instead of 2.
+
+ floppy=slow
+        Use PS/2 stepping rate:
+         " PS/2 floppies have much slower step rates than regular floppies.
+           It's been recommended that take about 1/4 of the default speed
+           in some more extreme cases."
+
+
+Supporting utilities and additional documentation:
+==================================================
+
+ Additional parameters of the floppy driver can be configured at
+runtime. Utilities which do this can be found in the fdutils package.
+This package also contains a new version of mtools which allows to
+access high capacity disks (up to 1992K on a high density 3 1/2 disk!).
+It also contains additional documentation about the floppy driver.
+
+The latest version can be found at fdutils homepage:
+ http://fdutils.linux.lu
+
+The fdutils releases can be found at:
+ http://fdutils.linux.lu/download.html
+ http://www.tux.org/pub/knaff/fdutils/
+ ftp://metalab.unc.edu/pub/Linux/utils/disk-management/
+
+Reporting problems about the floppy driver
+==========================================
+
+ If you have a question or a bug report about the floppy driver, mail
+me at Alain.Knaff@poboxes.com . If you post to Usenet, preferably use
+comp.os.linux.hardware. As the volume in these groups is rather high,
+be sure to include the word "floppy" (or "FLOPPY") in the subject
+line.  If the reported problem happens when mounting floppy disks, be
+sure to mention also the type of the filesystem in the subject line.
+
+ Be sure to read the FAQ before mailing/posting any bug reports!
+
+ Alain
+
+Changelog
+=========
+
+10-30-2004 :    Cleanup, updating, add reference to module configuration.
+                James Nelson <james4765@gmail.com>
+
+6-3-2000 :      Original Document