From mboxrd@z Thu Jan 1 00:00:00 1970 Received: (from majordomo@localhost) by oss.sgi.com (8.11.2/8.11.3) id g14K5tV30992 for linux-mips-outgoing; Mon, 4 Feb 2002 12:05:55 -0800 Received: from hermes.mvista.com (gateway-1237.mvista.com [12.44.186.158]) by oss.sgi.com (8.11.2/8.11.3) with SMTP id g14K5jA30793; Mon, 4 Feb 2002 12:05:45 -0800 Received: from mvista.com (IDENT:jsun@orion.mvista.com [10.0.0.75]) by hermes.mvista.com (8.11.0/8.11.0) with ESMTP id g14J1aB11076; Mon, 4 Feb 2002 11:01:36 -0800 Message-ID: <3C5EDB08.B4F2FF7B@mvista.com> Date: Mon, 04 Feb 2002 11:03:36 -0800 From: Jun Sun X-Mailer: Mozilla 4.72 [en] (X11; U; Linux 2.2.18 i686) X-Accept-Language: en MIME-Version: 1.0 To: "Maciej W. Rozycki" CC: Ralf Baechle , linux-mips@oss.sgi.com Subject: Re: CVS Update@oss.sgi.com: linux References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-linux-mips@oss.sgi.com Precedence: bulk "Maciej W. Rozycki" wrote: > > On Sun, 3 Feb 2002, Ralf Baechle wrote: > > > > Hmm, the assumption might be justifiable for the i386 only? Shouldn't > > > i8259.c be fixed instead? > > > > These are the ISA interrupts; many drivers make assumptions about the > > interrupts numbers, so we can't really change the numbers anyway. For > > any non-ISA interrupt it's number can be choosen freely. > > I don't think such assumptions are sane even for the i386 -- an I/O APIC > system is free to route ISA interrupts to whichever I/O APIC inputs are > available, not necessarily the low 16. The Intel MP Spec explicitly > allows such a setup -- ISA interrupts are only tied in default > configurations, which are rarely used (probably not at all these days). > > Anyway, only the drivers that read an IRQ number from jumpers or Flash > memory need to be checked, and these are a minority (3Com Ethernet cards > and possibly very few others). These that do probing (with probe_irq) or > simply take the number from an option will work automatically. > > While I agree for 2.4 it might be not the best idea to do such changes, > for 2.5 it's worth considering, isn't it? > This patch is from me. It merely reflects a change of the irq base mapping from 0x20 to 0x0. I think someone did this change for Malta board. A better solution is to have init_i8259_irqs() take an argument that is the base IRQ number, like many other irq controller code do. This way it is a board level decision as what block of IRQs i8259 should use. Jun