- Mon Aug 18, 2014 12:58 am
#173667
Hi All,
I have been working on a zynq arch which has 2 cortex9 inside. I 've been using Linux and I want to debug it.
Everything seems ok , I can stop to init phase of linux (from start_kernel) but i got a problem with breakpoint after system is up & running.
I try to better explain myself: If I stop gdb anytiwhere and want to debug step by step it works good... but if I set a breakpoint hw , resume GDB the cpu does not stop when code is executed.
So I tried with openocd to force GDB to use SW breakpoint ...in this way the breakpoint stop GDB but when i try sto step over it doesn' go ahead , remains stuck @ that point: the only way i have to move forward is to set the program counter the step above (from GDB set $pc+=4 ) and of course is not a good way 2 procede....
Anyone can help me?
I guess could be a cache issue...but i'm not complety sure.
Thanks for the help
edit:
In order to get it working the xilinx idle loop driver must be disabled in the kernel , i guess the WFI instruction does not work very well with OCD. I hope it should be usefull for anyone.
Marco
I have been working on a zynq arch which has 2 cortex9 inside. I 've been using Linux and I want to debug it.
Everything seems ok , I can stop to init phase of linux (from start_kernel) but i got a problem with breakpoint after system is up & running.
I try to better explain myself: If I stop gdb anytiwhere and want to debug step by step it works good... but if I set a breakpoint hw , resume GDB the cpu does not stop when code is executed.
So I tried with openocd to force GDB to use SW breakpoint ...in this way the breakpoint stop GDB but when i try sto step over it doesn' go ahead , remains stuck @ that point: the only way i have to move forward is to set the program counter the step above (from GDB set $pc+=4 ) and of course is not a good way 2 procede....
Anyone can help me?
I guess could be a cache issue...but i'm not complety sure.
Thanks for the help
edit:
In order to get it working the xilinx idle loop driver must be disabled in the kernel , i guess the WFI instruction does not work very well with OCD. I hope it should be usefull for anyone.
Marco