diff options
author | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
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committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-04-16 18:20:36 -0400 |
commit | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch) | |
tree | 0bba044c4ce775e45a88a51686b5d9f90697ea9d /Documentation/cdrom/optcd |
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history,
even though we have it. We can create a separate "historical" git
archive of that later if we want to, and in the meantime it's about
3.2GB when imported into git - space that would just make the early
git days unnecessarily complicated, when we don't have a lot of good
infrastructure for it.
Let it rip!
Diffstat (limited to 'Documentation/cdrom/optcd')
-rw-r--r-- | Documentation/cdrom/optcd | 57 |
1 files changed, 57 insertions, 0 deletions
diff --git a/Documentation/cdrom/optcd b/Documentation/cdrom/optcd new file mode 100644 index 000000000000..6f46c7adb243 --- /dev/null +++ b/Documentation/cdrom/optcd | |||
@@ -0,0 +1,57 @@ | |||
1 | This is the README file for the Optics Storage 8000 AT CDROM device driver. | ||
2 | |||
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. | ||
9 | |||
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. | ||
13 | |||
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/ | ||
18 | |||
19 | Before you can use the driver, you have to create the device file once: | ||
20 | # mknod /dev/optcd0 b 17 0 | ||
21 | |||
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. | ||
26 | |||
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. | ||
32 | |||
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: | ||
37 | |||
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 | ||
48 | |||
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! | ||
51 | |||
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. | ||
56 | |||
57 | Leo Spiekman (spiekman@dutette.et.tudelft.nl) | ||