Subject: Re: busspaceifying
To: Reinoud Zandijk <>
From: Chris Gilbert <>
List: tech-kern
Date: 02/14/2001 20:31:07
On Wednesday 14 February 2001  5:41 pm, Reinoud Zandijk wrote:
> Hi folks,
> In the arm32 port there are devices like `beep0 at vidc0' (with `vidc0 at
> mainbus?' that use DMA but are not using dmamem mappings trough the bus. I
> need this structure to be able to claim memory from a second free list for
> DMA to support the Kinetic card (added successfully).

Be warned that beep is broken (IMO) it should be part of the vidcaudio, so 
that you get beep0 at vidcaudio0 at vidc0 at mainbus0.  but that's a side 

> I've started to convert this `beep' device first for its pretty simple in
> design and only uses one dma mapping.

[snip code]

> So does that mean that the mainbus tag doesnt have the _dmamem_alloc ? and
> how can I write them? i.e. can I use the stuff in arm32/bus.h ?

Possibly, I didn't think that bus_space stuff was ever finished on arm32.  
Makefiles include bus_space_notimpl.o, which panics if you ever do any bus 
space calls, see sys/arch/arm32/dev/bus_space_notimpl.S

Note I'm not sure I'm right about this as I'm no bus_space expert :)