cvs commit: src/sys/dev/dcons dcons.c

[Marcel Moolenaar]

On Sun, Jul 11, 2004 at 04:11:16PM +0900, Hidetoshi Shimokawa wrote:
> I'd like to re-support remote debugging by dcons(4).
> Do you have any pointer for "new GDB debug port interface"?

The interface is defined in src/sys/gdb/gdb.h. A good example can
be found in src/sys/dev/uart/uart_dbg.c.

First GDB calls the probe function. The probe function is supposed
to return a priority (>=0). A negative priority means that the
debug port is dead or unusable. The uart(4) driver returns 0. So
does the sio(4) driver. If you want to give dcons priority over a
serial port, have the probe function return 1 or more.

After all the probe functions have been called, one debug port is
seleced as the current port. The init function for that port is
called so that it can initialize itself.

After that, the GDB backend will call the getc and putc functions
to send and receive packets. The interface is mostly character
oriented now, even though the GDB protocol is based on packets. If
this doesn't work as efficiently for firewire (or ethernet for that
matter) and have ideas to make it more friendly for you, let me
know. I welcome improvements and enhancements.

Thanks,

-- 
 Marcel Moolenaar	  USPA: A-39004		 marcel at xcllnt.net