Messages in this thread | | | Date | Mon, 15 Jul 2002 14:58:48 +0200 (CEST) | From | Joerg Schilling <> | Subject | Re: IDE/ATAPI in 2.5 |
| |
>From: "Richard B. Johnson" <root@chaos.analogic.com> >> >From root@chaos.analogic.com Fri Jul 12 22:18:47 2002 >> >> >As much as I hate IDE, IDE isn't going away. All my systems use SCSI >> >so on machines that have CD/ROMS, I use your libraries and your tools. >> >> >Maybe somebody should make CD/ROM code that directly talks to IDE via >> >/dev/hdwhatever, instead of expecting you to modify your code that >> >has worked so well for so long. >> >> This would be a really bad idea. >> >> Such a change would force me to add a 6th (and unneeded) new interface. >> Why? What problem would be solved if you did introduce such an interface? >>
>Well for one thing it eliminates the requirement to >include SCSI interface code on machines that don't >have SCSI. That's the practical aspect.
>Now, the esoteric. Do you truly think that it is >proper to encapsulate devices in various layers?
>The IDE interface, if it wasn't for the bug-workarounds, >is just a floppy disk interface that uses a different >controller chip. It is register-based, not message- >based. If you throw in a message-based control layer >(SCSI), what problems are you solving? It's a >rhetorical question. No answer is required.
If you like to use the floppy only via the ATA registers, then you don't like to be able to format media?
BTW: the overhead to set up DMA is higher than the overhead to set up a SCSI CDB.
Jörg
EMail:joerg@schily.isdn.cs.tu-berlin.de (home) Jörg Schilling D-13353 Berlin js@cs.tu-berlin.de (uni) If you don't have iso-8859-1 schilling@fokus.gmd.de (work) chars I am J"org Schilling URL: http://www.fokus.gmd.de/usr/schilling ftp://ftp.fokus.gmd.de/pub/unix - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |