- No more distinction between i/o-mapped and memory-mapped
devices. It's all "bus space" now, and space tags
differentiate the space with finer grain than the
bus chipset tag.
- Add memory barrier methods.
- Implement space alloc/free methods.
- Implement region read/write methods (like memcpy to/from
bus space).
This interface provides a better abstraction for dealing with
machine-independent chipset drivers.
'cflag' for the console. Normally set to TTYDEF_CFLAG, may be
overridden by machine-dependent console attachment code, as necessary.
(Alpha uses it to set cs8 -parenb.) Files including comvar.h now
need to include <sys/termios.h>, because comconscflag is of type
tcflag_t.
substantial reworking of the multi-port drivers, as they need to frob
bits in the io-port spaces of their children. As a result, the
commulti->com attachment interface is substantially more complex.
(This may be fixable in the future by making some of the code common,
but as long as io-port allocation checking is planned, it's necessary.)
