Date: Sun, 19 Feb 1995 00:45:32 +0900 (JST) From: Atsushi Murai <amurai@spec.co.jp> To: julian@tfs.com (Julian Elischer) Cc: dufault@hda.com, freebsd-hackers@freefall.cdrom.com Subject: Re: NEW_SCSICONF Message-ID: <199502181545.AAA20178@tama.spec.co.jp> In-Reply-To: <m0rfN58-0003wTC@TFS.COM> from "Julian Elischer" at Feb 16, 95 11:26:26 pm
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Well..
> Some of the things that need doing..
> 5/ the cd driver needs code for audio-read (I have that for toshiba drives
> at least). possibly dependent on drive manufacturer.
I have investgated and attempt this area but still not done... I have
both Toshiba and Pioneer(Sony) Techinical manual. Long time ago I try
to implement PhotoCD(XA) and CD-audio(DA) as a partitions. (Yes. for
audio/music, just 8 partions are not enough. but you can read them
through the raw device as same as normal file;-)
Anyway we should two things consider as follows,
1. How to assing TOC ?
Here is my idea.
- When new CD disk is loading, it's searching a TOC and
build a *cdfs* like procfs.
- *cdfs* contains a TAG - device file for mounting cd9660 or
Photo CD. and just creat name of file entries for audio data.
i.e. ls -l /cdfs0
-r--r--r-- 1 root operator 3265478 Nov 22 21:29 da0
-r--r--r-- 1 root operator 3265478 Nov 22 21:29 da1
brw-r----- 1 root operator 6, 0 Nov 22 21:29 cd00
brw-r----- 1 root operator 6, 1 Nov 22 21:29 cd01
2. Block size of CD-DA (2352bytes/block)
Block of DA is not multiple 2. So uio_offset is miss counting
with current strategy routine and caller. So uio is needed to
pass and calcurate by cdstrategy.
i.e.
int cdstrategy(bp,uio)
struct buf *bp;
struct uio *uio; <--- Here
{
struct buf *dp;
unsigned int opri;
3. Require Dyanmic MODE change (DA/Mode 0/Mode 1/Mode 2(XA)) by both
depend on CD-Drive and a TOC attribute in same cd disk.- It allow to
co-exist different MODE block specified TOC in same CD!!
4. Current cd9660 treat a block number as NOT absolute block number.
(Block number of CD is Absolute block number. But first TOC/partion
offset is 0. So It's OK with ordinal one partion cd-rom disk )
Atsushi.
--
Atsushi Murai Internet: amurai@spec.co.jp
System Planning and Engineering Co,.Ltd. Voice : +81-33833-5341
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