[linux-block.git] / Documentation / scsi / dc395x.rst

.. SPDX-License-Identifier: GPL-2.0

==================
dc395x SCSI driver
==================

Status
------
The driver has been tested with CD-R and CD-R/W drives. These should
be safe to use. Testing with hard disks has not been done to any
great degree and caution should be exercised if you want to attempt
to use this driver with hard disks.

This driver is evolved from `the original 2.4 driver
<https://web.archive.org/web/20140129181343/http://www.garloff.de/kurt/linux/dc395/>`_.
Problems, questions and patches should be submitted to the `Linux SCSI
mailing list <linux-scsi@vger.kernel.org>`_.

Parameters
----------
The driver uses the settings from the EEPROM set in the SCSI BIOS
setup. If there is no EEPROM, the driver uses default values.
Both can be overridden by command line parameters (module or kernel
parameters).

The following parameters are available:

safe
   Default: 0, Acceptable values: 0 or 1

   If safe is set to 1 then the adapter will use conservative
   ("safe") default settings. This sets:

		shortcut for dc395x=7,4,9,15,2,10

adapter_id
   Default: 7, Acceptable values: 0 to 15

   Sets the host adapter SCSI ID.

max_speed
   Default: 1, Acceptable value: 0 to 7

   ==  ========
   0   20   Mhz
   1   12.2 Mhz
   2   10   Mhz
   3   8    Mhz
   4   6.7  Mhz
   5   5.8  Hhz
   6   5    Mhz
   7   4    Mhz
   ==  ========

dev_mode
   Bitmap for device configuration

   DevMode bit definition:

      === ======== ========  =========================================
      Bit Val(hex) Val(dec)  Meaning
      === ======== ========  =========================================
       0    0x01       1     Parity check
       1    0x02       2     Synchronous Negotiation
       2    0x04       4     Disconnection
       3    0x08       8     Send Start command on startup. (Not used)
       4    0x10      16     Tagged Command Queueing
       5    0x20      32     Wide Negotiation
      === ======== ========  =========================================

adapter_mode
   Bitmap for adapter configuration

   AdaptMode bit definition

    ===== ======== ========  ====================================================
      Bit Val(hex) Val(dec)  Meaning
    ===== ======== ========  ====================================================
       0    0x01       1     Support more than two drives. (Not used)
       1    0x02       2     Use DOS compatible mapping for HDs greater than 1GB.
       2    0x04       4     Reset SCSI Bus on startup.
       3    0x08       8     Active Negation: Improves SCSI Bus noise immunity.
       4    0x10      16     Immediate return on BIOS seek command. (Not used)
    (*)5    0x20      32     Check for LUNs >= 1.
    ===== ======== ========  ====================================================

tags
   Default: 3, Acceptable values: 0-5

   The number of tags is 1<<x, if x has been specified

reset_delay
   Default: 1, Acceptable values: 0-180

   The seconds to not accept commands after a SCSI Reset


For the built  in driver the parameters should be prefixed with
dc395x. (eg "dc395x.safe=1")


Copyright
---------
The driver is free software. It is protected by the GNU General Public
License (GPL). Please read it, before using this driver. It should be
included in your kernel sources and with your distribution. It carries the
filename COPYING. If you don't have it, please ask me to send you one by
email.

Note: The GNU GPL says also something about warranty and liability.
Please be aware the following: While we do my best to provide a working and
reliable driver, there is a chance, that it will kill your valuable data.
We refuse to take any responsibility for that. The driver is provided as-is
and YOU USE IT AT YOUR OWN RESPONSIBILITY.
Commit	Line	Data
62e3bfa4 MCC	1	.. SPDX-License-Identifier: GPL-2.0
62e3bfa4 MCC	2
573a43f2 RD	3	==================
	4	dc395x SCSI driver
	5	==================
1da177e4 LT	6
	7	Status
	8	------
	9	The driver has been tested with CD-R and CD-R/W drives. These should
	10	be safe to use. Testing with hard disks has not been done to any
	11	great degree and caution should be exercised if you want to attempt
	12	to use this driver with hard disks.
	13
16853cd8 BS	14	This driver is evolved from `the original 2.4 driver
16853cd8 BS	15	<https://web.archive.org/web/20140129181343/http://www.garloff.de/kurt/linux/dc395/>`_.
7a94a131 BS	16	Problems, questions and patches should be submitted to the `Linux SCSI
7a94a131 BS	17	mailing list <linux-scsi@vger.kernel.org>`_.
1da177e4 LT	18
	19	Parameters
	20	----------
62e3bfa4	21	The driver uses the settings from the EEPROM set in the SCSI BIOS
1da177e4	22	setup. If there is no EEPROM, the driver uses default values.
992caacf	23	Both can be overridden by command line parameters (module or kernel
1da177e4 LT	24	parameters).
	25
	26	The following parameters are available:
	27
62e3bfa4	28	safe
1da177e4 LT	29	Default: 0, Acceptable values: 0 or 1
	30
	31	If safe is set to 1 then the adapter will use conservative
	32	("safe") default settings. This sets:
	33
	34	shortcut for dc395x=7,4,9,15,2,10
	35
62e3bfa4	36	adapter_id
1da177e4 LT	37	Default: 7, Acceptable values: 0 to 15
	38
	39	Sets the host adapter SCSI ID.
	40
62e3bfa4	41	max_speed
1da177e4	42	Default: 1, Acceptable value: 0 to 7
62e3bfa4 MCC	43
	44	== ========
	45	0 20 Mhz
	46	1 12.2 Mhz
	47	2 10 Mhz
	48	3 8 Mhz
	49	4 6.7 Mhz
	50	5 5.8 Hhz
	51	6 5 Mhz
	52	7 4 Mhz
	53	== ========
	54
	55	dev_mode
1da177e4 LT	56	Bitmap for device configuration
	57
	58	DevMode bit definition:
62e3bfa4 MCC	59
62e3bfa4 MCC	60	=== ======== ======== =========================================
1da177e4	61	Bit Val(hex) Val(dec) Meaning
62e3bfa4 MCC	62	=== ======== ======== =========================================
	63	0 0x01 1 Parity check
	64	1 0x02 2 Synchronous Negotiation
	65	2 0x04 4 Disconnection
	66	3 0x08 8 Send Start command on startup. (Not used)
	67	4 0x10 16 Tagged Command Queueing
	68	5 0x20 32 Wide Negotiation
	69	=== ======== ======== =========================================
	70
	71	adapter_mode
1da177e4 LT	72	Bitmap for adapter configuration
	73
	74	AdaptMode bit definition
62e3bfa4 MCC	75
62e3bfa4 MCC	76	===== ======== ======== ====================================================
1da177e4	77	Bit Val(hex) Val(dec) Meaning
62e3bfa4 MCC	78	===== ======== ======== ====================================================
	79	0 0x01 1 Support more than two drives. (Not used)
	80	1 0x02 2 Use DOS compatible mapping for HDs greater than 1GB.
	81	2 0x04 4 Reset SCSI Bus on startup.
	82	3 0x08 8 Active Negation: Improves SCSI Bus noise immunity.
1da177e4 LT	83	4 0x10 16 Immediate return on BIOS seek command. (Not used)
1da177e4 LT	84	(*)5 0x20 32 Check for LUNs >= 1.
62e3bfa4	85	===== ======== ======== ====================================================
1da177e4	86
62e3bfa4	87	tags
1da177e4	88	Default: 3, Acceptable values: 0-5
62e3bfa4	89
1da177e4 LT	90	The number of tags is 1<<x, if x has been specified
1da177e4 LT	91
62e3bfa4	92	reset_delay
1da177e4 LT	93	Default: 1, Acceptable values: 0-180
	94
	95	The seconds to not accept commands after a SCSI Reset
	96
	97
	98	For the built in driver the parameters should be prefixed with
	99	dc395x. (eg "dc395x.safe=1")
	100
	101
	102	Copyright
	103	---------
	104	The driver is free software. It is protected by the GNU General Public
	105	License (GPL). Please read it, before using this driver. It should be
	106	included in your kernel sources and with your distribution. It carries the
	107	filename COPYING. If you don't have it, please ask me to send you one by
	108	email.
62e3bfa4 MCC	109
62e3bfa4 MCC	110	Note: The GNU GPL says also something about warranty and liability.
1da177e4	111	Please be aware the following: While we do my best to provide a working and
62e3bfa4	112	reliable driver, there is a chance, that it will kill your valuable data.
1da177e4 LT	113	We refuse to take any responsibility for that. The driver is provided as-is
1da177e4 LT	114	and YOU USE IT AT YOUR OWN RESPONSIBILITY.