Floating point in 8260

Floating point in 8260

[zzh]

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I make a port to motorola 8260 ads based on 2.2 kernel.
Now i am sure the kernel is fuctional,because i can run a
simple program that fork process and write to stdout.
I use simple assembly to make system call and does not
use any c lib.
When i try to run bash,8260 loops inside FPunavailble
exception.The 2.2 kernel support 603 with a FP,but
how should i do with 603e.
>From this lists,i learned that someone else encounter
similar problem,they upgrade to a 8260 with FP.
I do not want to upgrade,how should i do?
Should i recompile the bash and c lib.How should i treat
float point.BTW,i have a apple G3,should i compile
these stuff on this machine?

 Best Regards.


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Re: Floating point in 8260

[Neil Russell]

As I understand it, there is no production 8260 without an FPU.  Current
production chips are rev A.1 which have an FPU, and new production are rev B
which will also have an FPU.  You probably have no choice for production, so
you should upgrade your test board if it has old an CPU.


Neil.



On Tue, May 30, 2000 at 11:19:15AM +0800, zzh wrote:
>
> I make a port to motorola 8260 ads based on 2.2 kernel.
> Now i am sure the kernel is fuctional,because i can run a
> simple program that fork process and write to stdout.
> I use simple assembly to make system call and does not
> use any c lib.
> When i try to run bash,8260 loops inside FPunavailble
> exception.The 2.2 kernel support 603 with a FP,but
> how should i do with 603e.
> >From this lists,i learned that someone else encounter
> similar problem,they upgrade to a 8260 with FP.
> I do not want to upgrade,how should i do?
> Should i recompile the bash and c lib.How should i treat
> float point.BTW,i have a apple G3,should i compile
> these stuff on this machine?

--
Neil Russell <caret@c-side.com>

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Re: Floating point in 8260

[Geir Frode Raanes]

On Mon, 29 May 2000, Neil Russell wrote:

> As I understand it, there is no production 8260 without an FPU.  Current
> production chips are rev A.1 which have an FPU, and new production are rev B
> which will also have an FPU.  You probably have no choice for production, so
> you should upgrade your test board if it has old an CPU.

I suppose I can tell since currently shipping 8260 come with FPU.
Early 8260 are just like the early 486SX - it does contain a FPU,
but it is disabled. But unlike the 486SX the 8260 FPU can be
reenabeled by some microcode patch - wich I do not have myself.
This is as much I know of this. If you are really nice to
Motorola then perhaps they will let you have this patch.

> > Should i recompile the bash and c lib.How should i treat
> > float point.BTW,i have a apple G3,should i compile
> > these stuff on this machine?

configure & make xgcc -nfp?
Then recompile GLibC (with soft float) I suppose.

--
  ******************************************************
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Re: Floating point in 8260

[Jim Lewis]

If you are dead-set against upgrading the CPU, you can run a root filesystem
that is COMPLETELY without FP instructions (built to use soft-float). The
MontaVista 8xx CDK should work fine.  Just make sure you don't mix it (the 8xx
CDK) with other binaries.

-Jim
zzh wrote:

> I make a port to motorola 8260 ads based on 2.2 kernel.
> Now i am sure the kernel is fuctional,because i can run a
> simple program that fork process and write to stdout.
> I use simple assembly to make system call and does not
> use any c lib.
> When i try to run bash,8260 loops inside FPunavailble
> exception.The 2.2 kernel support 603 with a FP,but
> how should i do with 603e.
> >From this lists,i learned that someone else encounter
> similar problem,they upgrade to a 8260 with FP.
> I do not want to upgrade,how should i do?
> Should i recompile the bash and c lib.How should i treat
> float point.BTW,i have a apple G3,should i compile
> these stuff on this machine?
>
>  Best Regards.
>
> _____________________________________________
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> --ΪÄãϲ°®ÓëÖ§³ÖµÄ263Ê׶¼ÔÚÏߣ¨http://www.263.net£©Í¶Ò»Æ±£¡
> ÎÒҪͶƱ£¡£¨http://fsurvey.cnnic.net.cn/survey/index.html£©
>


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