This README file is somehow obsolete, as the web page now has a rough
description of the driver and the README.tmscsim file in the package has
detailed help. However, it used to be there, so I don't want to remove it
immediately. Some info may not be up to date, though.   (KG, 98/12/28)


The DC390 (tmscsim) driver rev 2.0x 
=====================================

DESCRIPTION
-----------
The DC390 driver supports AM53C974-based PCI SCSI host adapters. It was
developed by a Tekram engineer to work with a Tekram DC390 (T) and enhanced
by me to support other AM53C974 based adapters as well. The driver's name is
tmscsim. 

Please don't confuse it with the AM53C974 driver also contained in the
kernel. That one has a couple of problems and the author has no time to
maintain it ...


NEWS
----
Since 1.11/2, there are a few changes
* Removed (arbitrary) MAX_DEVICES limit and alloc mem for DCBs (DeviceControl
  Blocks) dynamically. (This is the most dangerous change.)
* Renamed functions to consistently carry DC390_ (functions called from 
  outside) or dc390_ (internal funcs) prefix.
* Reworked the locking mechanism. Added spinlocks for SMP support. 
* Support for non DC390-adapters: Conservatice BIOS values are assumed or
  kernel/module parameters are used.
* /proc/scsi/tmscsim/? lets you now write and change config of the driver
* Changed LUN support behaviour: LUNs are not scanned for if disabled in
  BIOS, but devices w/ LUN>=1 can be added via the
  echo "scsi add-single-device H C I L" >/proc/scsi/scsi interface.
  (H=Host, C=Channel, I=SCSI ID, L=SCSI LUN)
* Uniform sourcecode for Linux-2.0.x and Linux-2.1.x (and probably soon 2.2.x).
* Documentation: README.tmscsim
* Lots of bug fixes.


PROC INTERFACE
--------------
The driver will display its seeting when reading from /proc/scsi/tmscsim/?.
With a similar format, you can change most of the settings. Case is ignored 
and you can shorten YES/NO to y/n, if you want to. '-' means not to change
the value. Example:
 cat /proc/scsi/tmscsim/0
 echo "MaxID 5 MaxLUN 4" >/proc/scsi/tmscsim/0
 echo "1 6 0 Y No n Yes - n" >/proc/scsi/tmscsim/0 
 cat /proc/scsi/tmscsim/0


BEWARE
------
The DC390 2.0 has proven stable, so far.
If you got important data on your SCSI disks, please make a backup before
testing, anyway. If you are not able to do this, please tell the kernel to
remount-ro your filesystem on finding errors (tune2fs -e remount-ro
/dev/XXX) and have a copy of your partition table at some safe location.
Having a floppy disk to boot linux from is also a good idea, in case
anything goes wrong. 
(ftp://student.physik.uni-dortmund.de/pub/linux/kernel/bootdisk.gz)
If you want to experiment with the driver, I recommend to compile it as
module to make it possible to delete and reinsert it, if necessary.


INSTALLATION
------------
If you don't have any recent kernel with the latest drivers in
linux/drivers/scsi/, please copy the files tmscsim.c tmscsim.h dc390.h,
scsiiom.c and README.tmscsim to linux/drivers/scsi/.

Then the usual: 

 cd linux
 make config or menuconfig or xconfig
 make dep; make clean
 make zlilo; make modules; 
 make modules_install; depmod -a (revision)

Reading the included README.tmscsim is a good idea. 
If your kernel is old (Older than 2.0.37-pre1 or older than 2.1.127), you
may also want to apply the dc390-120-kernel.diff file included into the
package to your kernel source tree. Otherwise, you would not be able to pass
parameters to the driver at boot time. 
(Which you only need, if you are not happy with the defaults and you need to
change this at boot time. This does not apply to the DC390 adapter itself,
as it has a BIOS to configure the adapter and store this into an EEPROM/
NVRAM. The driver takes the settings from there if available.)


BUGS
----
There may be, though they hide well. If you think, you found one, please
read the file README.tmscsim and contact me, if you still think, that
there's a problem.
Please report problems to me: Kurt Garloff, dc390@garloff.de