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Path: euryale.cc.adfa.oz.au!newshost.anu.edu.au!harbinger.cc.monash.edu.au!news.mel.connect.com.au!munnari.OZ.AU!spool.mu.edu!howland.reston.ans.net!gatech!news.mathworks.com!fu-berlin.de!news.dfn.de!RRZ.Uni-Koeln.DE!zpr.uni-koeln.de!se From: se@ZPR.Uni-Koeln.DE (Stefan Esser) Newsgroups: comp.unix.bsd.freebsd.misc Subject: Re: Can Multiple 946Cs share an IRQ? Date: 15 Jan 1996 19:38:37 GMT Organization: Institute for Mathematics, University of Cologne, Germany Lines: 47 Sender: se@Sysiphos (Stefan Esser) Message-ID: <4deaft$96i@news.rrz.uni-koeln.de> References: <DL78Mt.MsA@wlbr.iipo.gtegsc.com> NNTP-Posting-Host: sysiphos.mi.uni-koeln.de Bcc: se In article <DL78Mt.MsA@wlbr.iipo.gtegsc.com>, sms@wlv.iipo.gtegsc.com (Steven M. Schultz) writes: |> I recently added a second Buslogic 946C (the new one is a Rev E |> card, the original one is a Rev B card from a year ago) because |> I'd filled up the first SCSI chain. |> |> If the problem I'm seeing is fixed in 2.1 that's fine - I'll replace |> 2.0.5 with that as soon as I order the CD. |> |> Basically the system is out of IRQs so I need to share IRQ 11 for |> both 946C cards. Using 'level triggered' interrupts this should |> be possible if the underlying system supports it (with BSD/OS |> everything's happy as a clam sharing IRQ 11). Does FreeBSD 2.0.5 have |> support for shared IRQs for PCI (EISA too since it can level triggered |> interrupts)? 2.1R does support shared interrupts for PCI. The EISA code in -current has recently been reworked, and it will get that feature, too, and in fact winterrupt sharing between PCI and EISA cards will be possible. |> I did use the 'conflicts' clause in the kernel config file - without |> that the second 946C isn't probed due to the IRQ conflict. The 946C was only detected as an ISA device in 2.0.5. In 2.1R it has become a Plug'n'Play PCI device (i.e. you won't have to specify an IRQ in the kernel config file, the IRQ assigned to the PCI slot will automatically be used.). |> The autoconfig probing does indeed find both 946C cards and all the |> devices on them. But the first access of any device on the second |> controller hangs the system completely to the point where mashing |> the reset button is required. This is an obvious result of having two ISA drivers share one IRQ: One of the controller cards will never receive any interrupts ... Just try 2.1R, it ought to have got it right :) Regards, STefan -- Stefan Esser, Zentrum fuer Paralleles Rechnen Tel: +49 221 4706021 Universitaet zu Koeln, Weyertal 80, 50931 Koeln FAX: +49 221 4705160 ============================================================================== http://www.zpr.uni-koeln.de/~se <se@ZPR.Uni-Koeln.DE>