This is the mail archive of the crossgcc@cygnus.com mailing list for the crossgcc project.
Index Nav: | [Date Index] [Subject Index] [Author Index] [Thread Index] | |
---|---|---|
Message Nav: | [Date Prev] [Date Next] | [Thread Prev] [Thread Next] |
On Thu, 5 Feb 1998, Joel Sherrill wrote: [ ... ] > > I'm currently trying to learn enough to write such a stub. Any pointers? > > Other than whatever source and documentation is included with gdb, I do > not know of anything. gdb 4.16 has remote stubs for i386, m68k, and the > sparc. The last gdb snapshot I looked at also included stubs for the sh > and m32r. It also included support for a much wider variety of ROM > monitors. There is also one for the IDT R4600 (a MIPS 4000-series machine) available by anonymous ftp from ftp://ftp.cygnus.com/pub/embedded/r46kstub.tar.gz or, with slightly updated porting hints, at ftp://ftp.vvnet.com/gdb/r46kstub.tar.gz There is also a README file available at ftp://ftp.vvnet.com/gdb/r46kstub.README This stub differs from the ones in the gdb distribution in that it runs stand-alone in ROM. I wrote it, in fact, for initial board bring-up (a logic analyzer was used to debug the stub :-). > The pc stub over a com port should not be THAT difficult. There is > already an i386 stub included in the current gdb so it should be a matter > of doing the IO and integrating it. Then give the world instructions and > the code. :) > > Providing a stub for CPUs like the PowerPC would be more challenging but > the protocol is well-defined and starting with an example for a cpu you > understand would help. I suspect many folks would start with the m68k or > i386. :) When I wrote the R4600 stub I looked over the all the stubs bundled with gdb-4.16, especially the i386 stub because I knew that CPU, but decided in the end to start from the sh stub even though I did not know that CPU at all. I did so because the sh stub seemed to me to be by far and away the best organized and easiest to understand. > > I hope this helps. > Likewise ... > --joel Mike -- C. M. Heard/VVNET, Inc. heard@vvnet.com