Hi Martin, thanks for the hints. I'll check this soon.
I now have a parallella board for testing as well but unfortunately no breakout board yet to which I could connect a JTAG debugger. Hence I'll stick to QEMU for the moment. Cheers and have some nice holidays Johannes On Fri, 19 Dec 2014 16:49:53 +0100 Martin Stein <[email protected]> wrote: > Hi Johannes, > > Sorry for answering that late. I had overlooked your mail. > > Unfortunately the newest qemu version available for my system is 2.0.0 > so there might be differences in our observations. After modifying > your qemu config from "-m 1024" to "-m 256" I get serial output from > the beginning of 'init_kernel_up' till > 'Sctlr::write(Sctlr::init_virt_kernel());' in 'init_kernel_mp -> > Cpu::init_virt_kernel'. So this seems to be a problem with enabling > the MMU. > > You could do single-step at this point and check the IP after the > write to the SCTLR to see in which exception vector you end up (see > base-hw/src/core/spec/arm_v7/mode_transition.s: > _mt_kernel_entry_pic). I assume it to be either _dab_entry or > _pab_entry. If this is the case, reading the ARM registers DFSR/DFAR > respectively IFSR might help to track down the cause. > > One known problem that arises when enabling the MMU is that this also > enables ARM caches and branch predictors. You can try deactivating > them for test purpose. > > 'Z::set(v, 0);' in 'Sctlr::init_virt_kernel' in > 'base-hw/src/core/include/spec/arm_v7/cpu_support.h' and an empty > 'Arm_v7::inval_branch_predicts' method should disable branch > predictors. > > Should 'C::set(v, 0);' and 'I::set(v, 0);' in 'Sctlr::init_common' in > 'base-hw/src/core/include/spec/arm/cpu_support.h' and adapted TEX/C/B > fields in the 'CACHED' case in 'Translation::_create' in > 'base-hw/src/core/include/spec/arm/short_translation_table.h' should > disable ARM caches. > > You might also check wether your UART and your Core image are mapped > correctly 1:1 by instrumenting the translation-table methods. > > Cheers, > Martin > > On 15.12.2014 19:43, Johannes Schlatow wrote: > > Hey, > > > > I just started adding support for the Zynq SoC to base-hw (see [1]). > > > > As I don't have any Zynq hardware available yet, I tried running > > this on QEMU 2.1.2; I compiled the run/hw_info target. > > > > After applying some printf debugging ;), I figured out that the > > program dies (i.e. QEMU freezes) during kernel initialisation > > in init_virt_kernel(). I therefore tried attaching gdb to QEMU's > > internal gdb server, however, it seems to ignore my breakpoints. > > > > Hence my question: Do you guys have any experience with > > low-level/kernel debugging on QEMU? Maybe I am missing something or > > QEMU is just weird? > > > > [1] > > https://github.com/ValiValpas/genode/commit/4e375384d635d06626f0b226ac14e21f608d717a > > > > Cheers > > Johannes > > > > ------------------------------------------------------------------------------ > > Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server > > from Actuate! Instantly Supercharge Your Business Reports and > > Dashboards with Interactivity, Sharing, Native Excel Exports, App > > Integration & more Get technology previously reserved for > > billion-dollar corporations, FREE > > http://pubads.g.doubleclick.net/gampad/clk?id=164703151&iu=/4140/ostg.clktrk > > _______________________________________________ genode-main mailing > > list [email protected] > > https://lists.sourceforge.net/lists/listinfo/genode-main > > > > ------------------------------------------------------------------------------ > Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server > from Actuate! Instantly Supercharge Your Business Reports and > Dashboards with Interactivity, Sharing, Native Excel Exports, App > Integration & more Get technology previously reserved for > billion-dollar corporations, FREE > http://pubads.g.doubleclick.net/gampad/clk?id=164703151&iu=/4140/ostg.clktrk > _______________________________________________ genode-main mailing > list [email protected] > https://lists.sourceforge.net/lists/listinfo/genode-main -- Johannes Schlatow, M.Sc. IDA, Institute of Computer and Network Engineering Technische Universität Braunschweig Hans-Sommer-Str. 66 38106 Braunschweig - Germany Phone +49 531 391 - 9668 www.ida.ing.tu-bs.de [email protected] ------------------------------------------------------------------------------ Download BIRT iHub F-Type - The Free Enterprise-Grade BIRT Server from Actuate! Instantly Supercharge Your Business Reports and Dashboards with Interactivity, Sharing, Native Excel Exports, App Integration & more Get technology previously reserved for billion-dollar corporations, FREE http://pubads.g.doubleclick.net/gampad/clk?id=164703151&iu=/4140/ostg.clktrk _______________________________________________ genode-main mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/genode-main
