Hi Greg, Greg Ungerer wrote, > Hi Waldemar, > > On 25/08/16 07:34, Waldemar Brodkorb wrote: > > Hi Greg, > > Greg Ungerer wrote, > > > >> Hi Waldemar, > >> > >> Waldemar Brodkorb wbx at openadk.org wrote: > >>> Greg Ungerer wrote, > >>>> Hi Waldemar, > >>>> On 23/04/16 08:50, Waldemar Brodkorb wrote: > >>>>> Hi Greg, > >>>>> Greg Ungerer wrote, > >>>>> > >>>>>>> How could I generate the information for you? Do you have > >>>>>>> a kernel patch I would need to apply? I can bootup a kernel > >>>>>>> and execute code, I just can't type anything into the serial > >>>>>> > >>>>>> Attached is a kernel patch that modifies binfmt_flat to print > >>>>>> out the reloc number along with the reloc error. That way we can > >>>>>> map that back to the reloc entry number printed out in the verbose > >>>>>> output from elf2flt at compile time. > >>>>> > >>>>> Thanks for the patch, will try it. > >>>>> > >>>>>>> I am not sure any Qemu Cortex-M3/4 system emulation is > >>>>>>> available. > >>>>>> > >>>>>> Do you know of any qemu target machines that work out-of-the-box > >>>>>> with a stock linux kernel with MMU disabled? > >>>>> > >>>>> No. > >>>>> > >>>>>> I used to use the gdb/ARMulator many years ago, but the kernel > >>>>>> target machine (Atmel/at91eb01) is long gone in modern kernel > >>>>>> version. > >>>>> > >>>>> I tried three different qemu forks, but they all only provide > >>>>> system level emulation for bare-metal apps. Skyeye crashes for me > >>>>> and recent GDB doesn't contain the old Armulator stuff. > >>>>> > >>>>> I tried Qemu mainline to bootup versatilepb/vexpress Linux kernel > >>>>> without MMU, but get no output. > >>>> > >>>> Looking into the other ARM flat problem, I figured we need to get > >>>> this problem solved as well. > >>>> > >>>> Turns out it is not too hard to get a Versatile target built > >>>> and running on qemu in no-MMU mode. The only real change required > >>>> is the attached patch - which fixes the IO device addressing problem. > >>>> > >>>> With this patch and starting with the versatile_defconfig you > >>>> only need a couple of config changes and it will run on the > >>>> versatile target in qemu. You need to disable CONFIG_MMU > >>>> and set the DRAM sizing (base at 0, size 128MB). > >>>> > >>>> This patch is against a linux-4.4 kernel, and it looks like the > >>>> versatile target has gone device tree from 4.5 and newer - so > >>>> this patch won't apply or work on them as is. > >>> > >>> Can you show us the commandline you use? What -cpu do you use? > >> > >> To run qemu I use: > >> > >> qemu-system-arm -M versatilepb -nographic -kernel images/zImage -append > >> "console=ttyAMA0,115200" > >> > >> The running system reports: > >> > >> CPU: ARM926EJ-S [41069265] revision 5 (ARMv5TEJ), cr=00091176 > >> CPU: VIVT data cache, VIVT instruction cache > >> Machine: ARM-Versatile PB > >> > >> So its an ARM926 - but I didn't specify any CPU to qemu, I just > >> let it default to whatever is the versatilepb qemu default. > >> > >> Attached is the linux kernel config I used to generate kernel. > >> > >> Note that I have had to make a couple of changes to elf2flt to get > >> apps working. I'll send some emails about those soon. But that > >> doesn't affect getting the kernel running on qemu. > > > > I can't get it working. > > Can you explain what toolchain do you use? > > My own manually compiled toolchain. > > > > gcc version? binutils version? soft-float toolchain? > > gcc-5.4.0 > binutils-2.26 > > Toolchain targeted at arm-uclinuxeabi using hard-float > (as in --with-float=hard gcc configuration) > > > > Are you using arm or thumb instructions? > > ARM only. > > > > Can you show me gcc -v of your cross-compiler? > > Using built-in specs. > COLLECT_GCC=arm-uclinuxeabi-gcc > COLLECT_LTO_WRAPPER=/usr/local/libexec/gcc/arm-uclinuxeabi/5.4.0/lto-wrapper > Target: arm-uclinuxeabi > Configured with: ../configure --target=arm-uclinuxeabi --with-float=hard > --enable-multilib --with-system-zlib --disable-libsanitizer > --enable-languages=c,c++ --prefix=/usr/local > Thread model: single > gcc version 5.4.0 (GCC) > > Kernel is a pristine linux-4.4 with only the hardware IO patch > listed earlier in the thread applied. > > In the end I didn't need to modify elf2flt to get a working system > using an arm-uclinuxeabi toolchain.
Thanks for the background information, finally I can get it working, too. Thanks! Waldemar _______________________________________________ uClinux-dev mailing list uClinux-dev@uclinux.org http://mailman.uclinux.org/mailman/listinfo/uclinux-dev This message was resent by uclinux-dev@uclinux.org To unsubscribe see: http://mailman.uclinux.org/mailman/options/uclinux-dev
