[LITMUS^RT] staging updated

[Christopher Kenna]

On Fri, Sep 21, 2012 at 2:07 PM, Björn Brandenburg <bbb at mpi-sws.org> wrote:
>
>
> On 21.09.2012, at 19:54, Christopher Kenna <cjk at cs.unc.edu> wrote:
>
>> My changes were pretty trivial and the merge looks right to me. It
>> also compiled on amd64, so I removed the prop/ branch I made
>> yesterday. Glenn's changes don't work well on ARM. I get this error
>> when I try and compile for the ARM:
>>
>> itmus/built-in.o: In function `_frac':
>> /home/cjk/git/unc/litmus-rt/include/litmus/fpmath.h:35: undefined
>> reference to `__aeabi_ldivmod'
>> /home/cjk/git/unc/litmus-rt/include/litmus/fpmath.h:35: undefined
>> reference to `__aeabi_ldivmod'
>> make: *** [.tmp_vmlinux1] Error 1
>>
>> I understand not everyone uses this board, so they may not be able to
>> test on it. Glenn, we should talk about fixing this (in person or on
>> the list). I'm not familiar with this fpmath.h file, and it's not
>> critical to get it working at the moment, so I'm not going to try and
>> figure out what the issue is. Maybe there is something easy I can try?
>
> Yeah... didn't think of that. Many ARM CPUs do not have a division instruction. It has to be emulated in software.
>
> - Björn

Haven't looked at fpmath.h, but there is a do_div function for ARM
defined in: litmus-rt/arch/arm/include/asm/div64.h Is it useful Glenn?