ia64/linux-2.6.18-xen.hg

view Documentation/cdrom/optcd @ 524:7f8b544237bf

netfront: Allow netfront in domain 0.

This is useful if your physical network device is in a utility domain.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
author Keir Fraser <keir.fraser@citrix.com>
date Tue Apr 15 15:18:58 2008 +0100 (2008-04-15)
parents 831230e53067
children
line source
1 This is the README file for the Optics Storage 8000 AT CDROM device driver.
3 This is the driver for the so-called 'DOLPHIN' drive, with the 34-pin
4 Sony-compatible interface. For the IDE-compatible Optics Storage 8001
5 drive, you will want the ATAPI CDROM driver. The driver also seems to
6 work with the Lasermate CR328A. If you have a drive that works with
7 this driver, and that doesn't report itself as DOLPHIN, please drop me
8 a mail.
10 The support for multisession CDs is in ALPHA stage. If you use it,
11 please mail me your experiences. Multisession support can be disabled
12 at compile time.
14 You can find some older versions of the driver at
15 dutette.et.tudelft.nl:/pub/linux/
16 and at Eberhard's mirror
17 ftp.gwdg.de:/pub/linux/cdrom/drivers/optics/
19 Before you can use the driver, you have to create the device file once:
20 # mknod /dev/optcd0 b 17 0
22 To specify the base address if the driver is "compiled-in" to your kernel,
23 you can use the kernel command line item (LILO option)
24 optcd=0x340
25 with the right address.
27 If you have compiled optcd as a module, you can load it with
28 # insmod /usr/src/linux/modules/optcd.o
29 or
30 # insmod /usr/src/linux/modules/optcd.o optcd=0x340
31 with the matching address value of your interface card.
33 The driver employs a number of buffers to do read-ahead and block size
34 conversion. The number of buffers is configurable in optcd.h, and has
35 influence on the driver performance. For my machine (a P75), 6 buffers
36 seems optimal, as can be seen from this table:
38 #bufs kb/s %cpu
39 1 97 0.1
40 2 191 0.3
41 3 188 0.2
42 4 246 0.3
43 5 189 19
44 6 280 0.4
45 7 281 7.0
46 8 246 2.8
47 16 281 3.4
49 If you get a throughput significantly below 300 kb/s, try tweaking
50 N_BUFS, and don't forget to mail me your results!
52 I'd appreciate success/failure reports. If you find a bug, try
53 recompiling the driver with some strategically chosen debug options
54 (these can be found in optcd.h) and include the messages generated in
55 your bug report. Good luck.
57 Leo Spiekman (spiekman@dutette.et.tudelft.nl)