Fri Jun 28 18:55:07 PDT 1996

This file contains some helpful (hopefully! :^) information on what to do if
your Linux system won't boot properly.

Section 1: What to do if after the installation process, the machine will 
           not boot.

This problem is not uncommon.  The reason for it is that the kernel your system
tries to boot after installation is not the same as the one used to install (the
bootdisk kernel).  Typically the kernel that is installed to your hard drive 
will contain more device drivers, and sometimes one of them won't like some 
piece of hardware in your machine.

There are a couple of approaches that can be used to deal with this situation.
Perhaps the simplest solution is to open up the machine and pull any cards that
aren't crucial, and then try to reboot the system.  If this is successful, then
follow the instructions in the FAQ.TXT for building and installing a kernel
that is customized for your hardware.

Another approach (that doesn't involve opening the machine) is to try to use the
bootdisk you installed with to kickstart the system.  To do this, boot the disk
and then use the "mount" option to have the kernel boot the root partition on
your hard drive rather that a root/install disk.  Let's assume your root Linux
partition is on /dev/hda2.  To boot the system, you'd use this command at the
LILO prompt on the bootdisk:

mount root=/dev/hda2


Section 2:  Trying to get the kernel to detect hardware.

The first thing you should do is make sure you're using a kernel that supports
the hardware you're trying to use.  If it doesn't, you've got a few options for
how to add the support.  You can compile a custom kernel of your own, or you
can look for an appropriate pre-compiled kernel in the /kernels directory.
Another approach is to try loading a kernel module to add the extra support you
need.  This is usually the fastest and easiest way to get a device working, so
you might want to try it first.  Use 'vi' (or some other editor) to edit the
file /etc/rc.d/rc.modules.  Look for a module that supports the hardware you
want to get working, remove the '#' from the beginning of the line, and fill in
any extra parameters that the module might require.

If you install a new kernel, be sure to reinstall LILO afterwards (if you use 
it).  For more details on installing a kernel, see the FAQ.TXT.

There are a number of extra parameters that can be used on the LILO bootdisk
prompt, with Loadlin, or in your /etc/lilo.conf.  These flags help tell the
kernel which I/O port, IRQ, and so forth, that a particular piece of hardware
uses, so that if the kernel doesn't see a peripheral while autoscanning you
should be able to force detection by telling the kernel exactly where to look.

To use an extra flag with a bootdisk, put the flags after the standard command
used to boot the system.  So, to boot /dev/hda2 and try to force detection of
a Mitsumi CD-ROM drive with Mitsumi interface card, you might use something
like this at the LILO prompt:

mount root=/dev/hda2 mcd=0x300,11

To use a parameter with Loadlin, just add it to the end of the boot command
in a similar fashion:

loadlin vmlinuz root=/dev/hda2 mcd=0x300,11

Or, you can enclose the parameters in an append="" and add the line to your
/etc/lilo.conf.  Don't forget to reinstall lilo after editing the i
/etc/lilo.conf.  To do this, just type "lilo" as root.

Here's how the line you'd add to your /etc/lilo.conf looks:

append="mcd=0x300,11"

Here is a list of known kernel parameters from the Loadlin documentation:

    LOADLIN 1.5 ((C) 1994 lermen@elserv.ffm.fgan.de)
     and
    Linux version: 0.99.14, 0.99.15, 1.0, 1.1.47

This is a list of command line parameters recognized and interpreted by:
========================================================================

  1. LOADLIN
       ramdisk=size        (size in Kbytes)
     or
       ramdisk=size,no     (same as above, but diskchange prompt disabled)
                           e.g.:  ramdisk=1440,no
       vga=mode

  2. The Linux kernel
       mem=number       (for > 0.99.15,  number = end of physical memory in bytes)
       root=device
       ro
       rw
       no387
       debug            sets console_loglevel = 10
       no-hlt           disables check of HLT isntruction at startup

  3. init
       single
       auto
       ro,rw,no387   (forwarded from the kernel)

  4. Some drivers
       reserve=port1,num1,...,port5,num5 #reserves 80x86 ioports
       ether=irq,base_addr,mem_start,mem_end,dev_name
       hd=cyl,head,sect                  # for 2 drives you need this twice
                                         # first relates to drive 0
       bmouse=irq
       max_scsi_luns=n                          # (n should be between 1 and 8)
       st0x=base_address,irq                    # SEAGATE controller ST01/ST02
       tmc8xx=base_address,irq                  # Future Domain TMC-885,TMC-950
       t128=address,irq                         # Trantor T128/T128F/T228
       ncr5380=port,irq,dma                     # Generic NCR5380 driver
       aha152x=portbase,irq,scsiid,reconnect    # Adaptec AHA-152x driver
       cdu31a=portbase,irq,PAS                  # Sony CDU-31a.  Third parameter
                         # should be "PAS" if on a Pro-Audio Spectrum, or 
                         # nothing if on something else.
       xd=type,irq,iobase,dma
       mcd=port,irq
       sound=0x0TTPPPID, ..
       sbpcd=sbport,SoundBlaster
       sbpcd=LMport,LaserMate
       sbpcd=SpeaFXport,SPEA


  5. Environment
       All parameters of format  name=xxxx  which are not recogized by
       the kernel or a driver are put onto the environment.

       LOADLIN itself always puts  BOOT_IMAGE=imagefile  onto the environ-
       ment.  The user may put additional values onto the environment in
       order to allow  /etc/rc  to behave differently for a given condition.


==============================================================================

Following are detailed descriptions:


Parameters recognized by LOADLIN:
=================================

  root=device
  -----------
        device     may be a symbolic device name such as "/dev/hda2"
                   or the numeric device number (hex)
                   (highbyte=major, lowbyte=minor)
                   recognized symbolic devices (with their partitions) are:
                   "hda", "hdb", "sda", "sdb", "sdc", "sdd", "sde",
                   "fd", "xda", "xdb"

        There is a problem:

        Linus interprets the number following "/dev/hda" as a HEX number,
        The device names in  /dev  of the Slackware distribution, however,
        are numbered /dev/hda1 .. hda9 .. hda10 .. hda16,
        instead of   /dev/hda1 .. hda9 .. hdaa ..  hdaf  as Linus would have done.

        So, starting with version 1.3 of LOADLIN, I interpret the root device
        myself and pass the device numerically in the boot sector.
        My naming convention is a compromise which I hope will result in
        fewer irritations:

        If the number following "/dev/hda, hdb, sda ..."
        starts with 0, 0x or a..f, it is interpreted as a HEX number.
        If it starts with 1..9 it is interpreted as a decimal number.
        If none is appropriate, the string is passed to the command line.
        (some later kernel versions may have other device names).

        Examples:
        root=302
        root=0x201
        root=/dev/hda2
        root=/dev/sdaa   same as  root=/dev/sda10  or  /dev/sda0xa

  Ramdisk size option (used with 1.2.x kernels)

  ramdisk=size 
  ------------
        size      number of Kbytes for the RAMDISK device.
                  The image for the ramdisk is loaded by the
                  kernel at startup from a floppy drive, if
                  root=/dev/fdx  is also given.
                  After loading the image, the kernel then makes
                  the ramdisk the root device (NOT the floppy).
                  In addition to this, LOADLIN prompts for inserting
                  the ramdisk image into the floppy drive if it no
                  longer needs the drive (i.e. after loading the kernel).

  Ramdisk options for new (1.3.x and 2.0.x) kernels

  load_ramdisk=1
  --------------
                  This option tells the kernel that you wish to load
                  a ramdisk.  With new Linux kernels, a size does not
                  need to be specified -- the kernel will dynamically
                  allocate the needed memory as the kernel is loaded.

  prompt_ramdisk=1
  ----------------

                  This option tells the kernel that you wish to be prompted
                  to insert the ramdisk before the kernel tries to load it.
                  Useful when loading the ramdisk from floppy disk.

  vga=mode
  --------
        mode      -3  the user is asked to specify the VGA mode
                 ask  equal to -3
                  -2  80x50 extended VGA mode
            extended  equal to -2
                  -1  80x25 normal mode
              normal  equal to -1
                   0  as if "0" was entered at the boot prompt
                   .
                   .
                   n  as if the number "n" was entered at the boot prompt

  ro
  --
        "ro" forces the root device to be mounted read-only (Not for UMSDOS!)

  rw
  --
        "rw" forces the root device to be mounted read/write.

------------------------------------------------------------------------------

Parameters recognized only by the kernel:
=========================================

  mem=number
  ----------
        number     End of physical RAM, this is recognized by kernels
                   of 0.99.15 and higher and is useful if the exact
                   installed RAM size cannot be determined automatically.

  root=device
  -----------
        device     May be a symbolic device name such as "/dev/hda2"
                   or the numeric device number (highbyte=major, lowbyte=minor)
                   Recognized symbolic devices (with their partitions) are:
                   "hda", "hdb", "sda", "sdb", "sdc", "sdd", "sde",
                   "fd", "xda", "xdb"
                   But NOTE: old kernels < 1.1.47 have xda=0xC00, xdb=0xC40
                             newer kernels have        xda=0xD00, xdb=0xD40
        example:
        root=302
        root=/dev/hda2

!!      NOTE:   Older kernels ( below Linux 1.0.5 ) have a little bug in
!!              (init/main.c), but it is of little concern:
!!               The last part of the symbolic device name ("hda2") is
!!               passed as option parameter to  init, so init will
!!               say "illegal option", but continue without errors.
!!
!!              Of greater concern is the too-small static buffer
!!              "command_line" (80 bytes, in init/main.c).   It is
!!              preferable to set it to 512 and recompile the kernel.
!!
!!              This bug is fixed with Linux 1.0.5, the "command_line"
!!              is now 256 by default and (if needed ) can easily be changed
!!              with   #define COMMAND_LINE_SIZE xxxx  in init/main.c  (to a
!!              maximum size of 2047).


  no387
  -----
        "no387" disables use of the hardware math coprocessor.

  since 1.1.47 (or perhaps earlier) the following options are no more
  passed to init:

  ro,rw,no387
  -----------


  the following are new:


  debug  sets console_loglevel = 10
  -----

  no-hlt
  ------
         disables check of HLT instruction at startup.
         If you have a clone 486, this option is *very* usefull.

------------------------------------------------------------------------------

Option Parameters recognized by "init":
=======================================

  single
  ------
        Enter "single user mode" on boot


  auto
  ----

  ro,rw,no387   (forwarded from kernels < 1.1.47).   (see !!comment!! above)
  -----------


------------------------------------------------------------------------------



Configuration of ethernet cards:
================================

  ether=irq,base_addr,mem_start,mem_end,dev_name
  ---------------------------------------------
        irq        number, IRQ-number (3..15)
        base_addr  number, IO-base (0x280,...)
        mem_start  number, shared mem start
        mem_end    number, shared mem end
        dev_name   string,
                        eth0..3     all configured ethernetcards
                        dl0         D-Link DE600 pocket adaptor
                        atp0        AT-LAN-TEC (RealTek) pocket adaptor
                        plip0..2    parallel IP (PLIP)
                        sl0..3      serial IP (SLIP)
        example:
                ether=10,0x280,0xc8000,0xcbfff,eth0

  related files: net/inet/eth.c, drivers/net/Space.c

------------------------------------------------------------------------------

Reserving I/O port space:
=========================

  reserve=port1,num1,...,port5,num5
  ---------------------------------

        portn     first IOport-address in range
        numn      number of addresses in this range to reserve
                  (there will be bits set to "1" in "ioport_register")

  related files:  kernel/ioport.c


------------------------------------------------------------------------------

Setting hard disk parameters for the root device:
=================================================

  hd=cyl,head,sect
  ---------------
         # NOTE: if you have two drives, you must put
         #       two hd= params into the commandline
         #       the first for drive 1, the second for drive 2
         #       eg.
         #       loadlin zimage hd=1001,15,17 hd=989,15,56 root=/dev/hdb2 ro
         #       (this example from my machine however is not needed,
         #       you need it only, if Linux can't get the drive params properly
         #       from the BIOS).
  related files: drivers/block/hd.c
  config:        CONFIG_BLK_DEV_HD

------------------------------------------------------------------------------

Setting the IRQ for the bus-mouse:
==================================

  bmouse=irq
  ----------
  related files: drivers/char/busmouse.c
  config:        CONFIG_BUSMOUSE



------------------------------------------------------------------------------

Parameters for SCSI controllers:
================================

  max_scsi_luns=n                           (n should be between 1 and 8)

  st0x=base_address,irq                     SEAGATE controller ST01/ST02

  tmc8xx=base_address,irq                   Future Domain TMC-885,TMC-950

  t128=address,irq                          Trantor T128/T128F/T228

  ncr5380=port,irq,dma                      Generic NCR5380 driver

  aha152x=portbase,irq,scsiid,reconnect     Adaptec AHA-152x driver



  related files: drivers/scsi/seagate.c, t128.c, g_NCR5380.c, aha152x.c

  config:        CONFIG_SCSI_SEAGATE, CONFIG_SCSI_T128,
                 CONFIG_SCSI_GENERIC_NCR5380, CONFIG_SCSI_AHA152X


------------------------------------------------------------------------------

Parameters for SCSI Tapes:
=========================

  st=buffer_size,write_threshould,max_buffers

     buffer_size       Size of tape buffer in Kbyte (i.e. ST_BLOCK_SIZE)
     write_threshould  Number of Kbytes to buffer before write.
                       (must be < buffer_size)
     max_buffers       Number of buffers to reserve

  related files: drivers/scsi/st.c
  config:        CONFIG_CHR_DEV_ST

------------------------------------------------------------------------------

Parameter for XT hard disk controller (DTC 5150X):
==================================================

  xd=type,irq,iobase,dma
  ----------------------

  related files: drivers/block/xd.c
  config:        CONFIG_BLK_DEV_XD

------------------------------------------------------------------------------
Parameter for Sony CDU-31/33a CDROM driver:
===========================================

  cdu31a=iobase,irq,PAS
  ---------------------

  related files: drivers/block/cdu31a.c
                 include/linux/cdu31a.h
  config:        CONFIG_CDU31A

  WARNING -    All autoprobes have been removed from the driver.
               You MUST configure the CDU31A via a LILO config
               at boot time or in lilo.conf.  I have the
               following in my lilo.conf:
 
                 append="cdu31a=0x1f88,0,PAS"
 
               The first number is the I/O base address of the
               card.  The second is the interrupt (0 means none).
               The third should be "PAS" if on a Pro-Audio
               spectrum, or nothing if on something else.
 

------------------------------------------------------------------------------
Parameter for Mitsumi CDROM driver:
===================================

  mcd=port,irq
  ------------

  related files: drivers/block/mcd.c
  config:        CONFIG_MCD


------------------------------------------------------------------------------

Parameter for sound cards:
==========================

  sound=0x0TTPPPID, ..
  ----------------
     all values are enbedded in one longint, the above format
     shows a hex number, each place is a hex-digit

     TT         Supported card type.
                This is the index into the list of configured cards
                If all cards are configured (which normally is not the case)
                the following order is kept:
                        Roland MPU-401
                        Gravis Ultrasound
                        ProAudio Spectrum
                        SoundBlaster
                        SoundBlaster 16
                        SB16 MPU-401 (SB16-MIDI port)
                        AdLib

     PPP        Port Address

     I          IRQ

     D          DMA Channel


  related files: drivers/sound/dev_table.h,dev_table.c
  config:        CONFIG_SOUND

------------------------------------------------------------------------------

Parameter for IDE-style CD-ROM device driver (Kotobuki/Matsushita/Panasonic):
=============================================================================

  sbpcd=sbport,SoundBlaster
  ------------------------
  sbpcd=LMport,LaserMate
  ----------------------
  sbpcd=SpeaFXport,SPEA
  ----------------------

        sbport     soundblaster base port +0x10 (i.e 0x230 = 0x220+0x10)
        LMport     MPU-type port at 0x300 or equivalent
        SpeaFXport base port on SpeaFX card

  related files: drivers/block/sbpcd.c
  config:        CONFIG_SBPCD



------------------------------------------------------------------------------