On Fri, Jun 15, 2012 at 9:53 AM, Vaclav Peroutka <[email protected]> wrote: > >> > Can you point me where to get more info about single stepping ? It seems to >> me, that it is OpenOCD's weakness. Tomorrow I will hopefully get Lauterbach >> license to test this feature. But truth is that I can not do single stepping >> on >> my system with OpenOCD/gdb. >> >> Then you have something misconfigured. Single stepping and breakpoints >> definitely works. You could help yourself by describing the problem in >> more detail, like which Cortex-M3 you are using, which adapter, the >> configuration of OpenOCD, and the steps you take to determine if >> stepping works or not. > > I am running CM3 core in Xilinx FPGA. I have external FLASH at 0x7000_0000. I > use Amontec JTAGKey Tiny. > > I know that single stepping works in ICode memory region. I am however > affected by this feature of Cortex M3: > http://forums.arm.com/index.php?/topic/14005-debugging-cortex-m3-from-external-flash/
In an FPGA you should have the possibility to map the external flash to < 0x20000000 like the above link suggests, no? > The question is, how single stepping is implemented in OpenOCD. Two files are > attached. One is 'stepi' in FLASH (hardfault) and one is 'stepi' in RAM > (works). I want to track whether 'stepi' is made with writing into NVIC DHCSR > register C_STEP bit ( DDI0337G page 10-4) or just by setting breakpoint (in > case of FLASH by setting HW breakpoint which ends with HardFault). > > From logs attached it seems to me that 'stepi' uses breakpoints instead DHCSR. It does when "cortex_m3 maskisr" is set to auto instead of on or off. Auto is the default since that feature was implemented a while back. I still think it has a few quirks though, because it doesn't always do what I want. If you set on or off you should find that you can single-step wherever you want. However you still wont be able to set any breakpoints (including doing source level stepping), so the right solution is probably to not have the flash at 0x70000000 if you have a choice. /Andreas ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ OpenOCD-devel mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/openocd-devel
