[U-Boot] [PATCH v2 0/4] [ARM] Add KGDB support for ARM platforms

[Tonny Tzeng]

This patchset adds KGDB support for ARM platforms.

Since the KGDB support for ARM is through the undef instruction handler,
we need to add code to the startup file to restore the user context after
exception.  Unfortunately, each ARM variant has his own start.S, so please
reference the patch designed for arm720 to add the 'bad_restore_user_regs'
logic to your ARM start-up file.

v1 - initial patchset
v2 - (a) move code, which should be common to all arch, to common/kgdb.c;
         add two new weak funcs to common/kgdb_stubs.c, and separate these
         common code to the patch "KGDB set / remove breakpoints".
     (b) remove the watchdog func during the board initialization.
     (c) flush all cache after mangling instructions.

Best Regards,
Tonny