Subject: Re: bus space macros
To: Michael C. Richardson <mcr@sandelman.ottawa.on.ca>
From: Jason Thorpe <thorpej@nas.nasa.gov>
List: tech-kern
Date: 10/03/1997 16:21:39
On Fri, 03 Oct 1997 18:32:53 -0400 
 "Michael C. Richardson" <mcr@sandelman.ottawa.on.ca> wrote:

 >   What is the difference between:
 > 	bus_space_read_region_4
 >   and
 > 	bus_space_read_multi_4
 > 
 >  *	void bus_space_read_multi_N __P((bus_space_tag_t tag,
 >  *	    bus_space_handle_t bsh, bus_size_t offset,
 >  *	    u_intN_t *addr, size_t count));

This is like "insb", "insw", "insl", etc.  I.e. read multiple times
from a single address and fill a buffer.

 >  *	void bus_space_read_region_N __P((bus_space_tag_t tag,
 >  *	    bus_space_handle_t bsh, bus_size_t offset,
 >  *	    u_intN_t *addr, size_t count));

...this is like a memcpy from bus space into buffer.

Jason R. Thorpe                                       thorpej@nas.nasa.gov
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