[U-Boot-Users] ARM missing __udivdi3 in lib_arm or fix 64bit division in nand_util.c?

[Dirk Behme]

Håvard Skinnemoen wrote:
> On 7/31/07, Dirk Behme <dirk.behme at googlemail.com> wrote:
> 
>>In lib_arm __udivsi3 and friends are available, but __udivdi3 is
>>missing. There is a fix by modifying nand_util.c
>>
>>http://sourceforge.net/mailarchive/forum.php?thread_name=468D2650.10603%40rfo.atmel.com&forum_name=u-boot-users
>>
>>to not do any 64bit divisions any more. Now, I wonder what is the
>>correct fix for this? Should lib_arm provide __udivdi3 as well or
>>should nand_util.c be fixed as in above link to avoid 64bit divisions?
> 
> I can't speak for ARM, but I believe this is a problem for most
> architectures. In general, I think we should seriously consider moving
> lib_avr32/div64.c into lib_generic and start to use it for 64-bit
> division instead of relying on libgcc. U-Boot NG has already done
> this.

Something like in attachment?

> In this particular case, I think it's just ridiculously expensive to
> do _three_ 64-bit divisions just to implement a simple progress bar
> and they should all go away. It looks like Patrice's patch might give
> a bit weird results when crossing a 4G boundary but I don't see any
> easy way around it. Perhaps we should just drop the whole percentage
> complete thing and just show a nice N / M fraction?

Sounds good! Do you have some code for this?

Dirk


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