From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id ; Wed, 8 Aug 2001 14:55:21 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id ; Wed, 8 Aug 2001 14:55:12 -0400 Received: from mta1n.bluewin.ch ([195.186.1.210]:14760 "EHLO mta1n.bluewin.ch") by vger.kernel.org with ESMTP id ; Wed, 8 Aug 2001 14:55:00 -0400 Message-ID: <3B6E44EE000F26DC@mta1n.bluewin.ch> (added by postmaster@bluewin.ch) From: "Per Jessen" To: "linux-kernel@vger.kernel.org" , "Mark H. Wood" Date: Wed, 08 Aug 2001 21:03:14 +0200 Reply-To: "Per Jessen" X-Mailer: PMMail 98 Professional (2.01.1600) For Windows 95 (4.0.1212) MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Subject: Re: how to tell Linux *not* to share IRQs ? Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 8 Aug 2001 12:13:40 -0500 (EST), Mark H. Wood wrote: >On Wed, 8 Aug 2001, Andrew McNamara wrote: >[snippage] >> The problem is largely historical - each interrupt traditionally had a >> physically line associated with it, and lines on your backplane were a >> limited resource. >> >> If you were to do it again these days, you might have some sort of >> shared serial bus, so devices could give detailed data to the cpu >> (not only to uniquely identify the interrupting device, but also >> identify sub-devices - say a USB peripheral). > >See for example "vectored interrupts" on the PDP10. The device driver >tells the device where the driver's ISR is, and when the device >interrupts, it puts that address on the bus. The interrupt logic jumps >directly to the ISR, which "knows" it is the only driver that would be >interested in this interrupt. (You could set up a jump table if you >wanted to, so that each device of the same type could identify itself >uniquely, but that typically wasn't a big problem in '10 installations >where multiples were most likely in a PDP11 on the other side of a DTE20, >or Massbus devices on a single RH20.) > >Apparently this idea is now so old that it is new. :-) Yeah - I believe the same was possible on the Z80 - though I'd have to go read the manual to be certain. regards, Per Jessen, Zurich Windows 2001: "I'm sorry Dave ... I'm afraid I can't do that." regards, Per Jessen, Zurich http://www.enidan.com - home of the J1 serial console. Windows 2001: "I'm sorry Dave ... I'm afraid I can't do that."