Subject: Re: Machine-independent bus DMA interface proposal
To: None <>
From: Wolfgang Solfrank <>
List: tech-kern
Date: 09/23/1996 14:28:50
> 	kva		The kernel virtual address of the buffer
> 			to be mapped.

What about DMA to somewhere not in kernel vitual address space? 

Note that e.g. the current i386 port is quite scarce on kernel virtual address
space, and I've (actually a friend of mine has) got a machine with two frame
grabbers that both will want quite significant memory (easily several MB) to
dma their data to.  I'd like to have the interface support this too.

Something like having bus_dmamem_alloc() return a cookie that can be used as
argument to bus_dmamap_load(), and, if needed, can also be used to map the
memory into kernel virtual space.
ws@TooLs.DE     (Wolfgang Solfrank, TooLs GmbH) 	+49-228-985800