Re: supporting hw break/watch for embedded ppc

[Andrew Cagney <ac131313@redhat.com>]

>> > I have an mpc855 remote stub that implements Z0/z0.
>> > This worked entirely as expected.  Auto-detection
>> > used to attempt Z0, discover it was unsupported,
>> > and refrained from ever trying it again.  Naively I
>> > assumed that the remaining Zt variants would behave
>> > similarly.  This is not the case.
> 
>> 
>> It should be the case.
>> 
> 
>> > So where do I go to enable ppc hw breaks/watches?
> 
>> 
>> ``set debug remote 1'' to see exactly what the host/target are doing.
> 
> 
> Been there.  Done that.
> 
> The culprit is remote.c/remote_check_watch_resources
> which is hardwired via the earlier definitions:
> 
>   int remote_hw_watchpoint_limit = 0;
>   int remote_hw_breakpoint_limit = 0;

Have you tried:

(gdb) help set remote hardware-breakpoint-limit
Set the maximum number of target hardware breakpoints.
Specify a negative limit for unlimited.


> For now I have added comparisons between chip names
> and TARGET_ARCHITECTURE->printable_name along with
> corresponding known numbers of resource.  It ain't
> pretty but it does work.
> 
> Am I missing something?

There is a discussion and thread about improving the way GDB queries the 
target for its level of watchpoint support.  It involves some 
re-aranging of the breakpoints though (look for a thread between my 
self and Eli).

I've been to busy fixing up frames.

Andrew