Re: gdb port to or1k

["Marko Mlinar" <Marko.Mlinar@campus.fri.uni-lj.si>]

> I believe that Andrew Cagney mentioned the ser-* abstraction GBD uses
> for serial ports.  It may be necessary to do something equivalent for
> parallel ports.
We would really appreciate that. And, like Damjan said -- parallel ports
are becomming more and more used.

> Since the ioctl's used by serial tty's is much more standardized on
> UNIX and UNIX-like systems (e.g. sgtty, termio or termios), support
> for all is located in one source file ser-unix.c.  For parallel, we
> might need par-hp.c, par-sun.c, etc.  It won't be a requirement for
> you to supply implementations for all platforms, just that the scheme
> be extensible and not preclude other people adding support for their
> platforms.
Our interface is designed in a way, that it needs 8 outputs and 3 inputs.
This can be accomplished by centronics (oldest parallel port mode) and
is fully supported by IOCTLs (LP driver).
But, this kind of interface would be pretty slow. It would be much better
if we use INP and OUTP, where port addresses and interface is same
for all parallel ports. It would be nice if this faster option would be
available
for at least most popular hosts (Linux, win, sun).
Looking it long term for GDB - parallel port can be much faster (especially
bidirectional - EPP or ECP) than serial ports or ethernet, so many vendors
may choose it as a base for their remote protocol.

Marko