sk/msk no more
Bruce M. Simpson
bms at FreeBSD.org
Tue Mar 24 08:07:51 PDT 2009
Wilkinson, Alex wrote:
> 0n Fri, Mar 20, 2009 at 12:42:08PM -0400, John Baldwin wrote:
>
> >mcfg is a mechanism for doing faster PCI config access using a memory mapped window.
>
> As opposed to what ?
>
As opposed to bit-banging all PCI configuration space accesses through a
couple of low ISA I/O space ports (PCI Configuration Mechanism #1... in
the PCI SIG specs.) :-)
For years PCI was an x86/Intel only thing, architectures which don't
have this notion of ISA I/O port space have used memory mapped windows
like this for years.
cheers,
BMS
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