Date: Sat, 30 Sep 1995 21:54:16 +0100 (MET)
From: Alain Kalker <alain@Wit401402.student.utwente.nl>
Reply-To: A.C.P.M.Kalker@student.utwente.nl
To: Bruce Evans <bde@zeta.org.au>
Cc: hackers@freebsd.org, julian@ref.tfs.com
Subject: Re: correctness of isa.c
In-Reply-To: <199509301130.VAA32657@godzilla.zeta.org.au>
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On Sat, 30 Sep 1995, Bruce Evans wrote:

> >(also while we're about it, why is id_irq a bitfield?
> >it's almost believable, but is there a really good reason?)
> 
> There is no good reason, at least now.  The bitmap is more general
> except it doesn't allow out of bounds values, but nothing uses the
> flexibility, and lots of things assume that only one bit is set
> (things that do ffs(id_irq) won't work right if multiple bits are
> set).
> 
> Bruce
> 

Any chance of making id_drq a bitfield as well? This would solve the 
problems that will arise when writing drivers for the next generation 
multimedia add-on boards which use multiple DMA channels. In fact the 
problem already exists in the sound driver, which currently (ab)uses
id_flags for a second DMA channel.

---
Alain