Subject: Re: FreeBSD Bus DMA
To: Jonathan Stone <firstname.lastname@example.org>
From: Jason Thorpe <email@example.com>
Date: 06/11/1998 16:16:38
On Thu, 11 Jun 1998 16:11:42 -0700
Jonathan Stone <jonathan@DSG.Stanford.EDU> wrote:
> one of the things Justin added was a driver-specific filter function.
> Justin says that's a better way to detect mappings that oculd tickle
> driver bugs. VLB buslogic boards were given as a specific example; it
> sounds plausible to me. (I'd assume that if NetBSD added this, the
> filter argument would be NULL in almost all cases).
The only VLB BusLogic bug I'm aware of is the inability to properly
do DMA using 32-bit addresses. Our driver currently handles that case.
> Does that count as concrete justification -- at least if the
> filter-function works without switching to a callback-based model?
Jason R. Thorpe firstname.lastname@example.org
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