How to enable NEON instruction Support in the kernel

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Sanjeev Kumar Verma

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Jul 22, 2009, 10:30:30 AM7/22/09
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Hi,
I get the illegal instruction error at runtime upon usage of
components containing the Neon Instructions. I hope that if I know how
to enable the NEON instruction Support in the kernel, my problem will
be resolved!
Regards,
Sanjeev Kumar Verma

Koen Kooi

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Jul 22, 2009, 10:39:50 AM7/22/09
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Op 22 jul 2009, om 16:30 heeft Sanjeev Kumar Verma het volgende
geschreven:

>
> Hi,
> I get the illegal instruction error at runtime upon usage of
> components containing the Neon Instructions. I hope that if I know how
> to enable the NEON instruction Support in the kernel, my problem will
> be resolved!

zcat /proc/config.gz | grep NEON
CONFIG_NEON=y

It's enabled over here.

regards,

Koen

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Sanjeev Kumar Verma

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Jul 22, 2009, 11:19:00 AM7/22/09
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hi,
I did not get you. What should I do to enable the Neon Instruction
support?
I am using the Android port for beagle board (which includes the
kernel source also )downloaded from
http://labs.embinux.org/index.php/Android_For_OMAP3_with_Gstreamer_Integration.

Regards,
Sanjeev Kumar Verma
>  PGP.sig
> < 1KViewDownload

Sanjeev Kumar Verma

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Jul 22, 2009, 12:19:23 PM7/22/09
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Rupesh,
I got the way to Enable the neon support in the kernel in two steps -
I run these command on the kernel make file
1. make omap3_beagle_android_defconfig
2. make menuconfig
For enabling neon,
Floating point emulation ---> select NEON Advanced SIMD Extension
support and FastFPE math emulation (EXPERIMENTAL)

then exit

and yes while exiting

My Qs are -
Q1. if I build the Entire Android again, will it overwrite the neon
enable settings which I have done?
Q2 Which file among omap3_beagle_android_defconfig and
dss_omap3_beagle_defconfig has to be selected in the first command?
Q3 How to build the kernel alone?

Regards,
Sanjeev Kumar Verma



On Jul 22, 8:19 pm, Sanjeev Kumar Verma <sanjeev1...@gmail.com> wrote:
> hi,
> I did not get you. What should I do to enable theNeonInstruction
> support?
> I am using the Android port for beagle board (which includes thekernelsource also )downloaded fromhttp://labs.embinux.org/index.php/Android_For_OMAP3_with_Gstreamer_In....
>
> Regards,
> Sanjeev Kumar Verma
>
> On Jul 22, 7:39 pm, Koen Kooi <k...@beagleboard.org> wrote:
>
> > Op 22 jul 2009, om 16:30 heeft Sanjeev Kumar Verma het volgende  
> > geschreven:
>
> > > Hi,
> > > I get the illegal instruction error at runtime upon usage of
> > > components containing theNeonInstructions. I hope that if I know how
> > > to enable theNEONinstruction Support in thekernel, my problem will

Koen Kooi

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Jul 22, 2009, 12:29:11 PM7/22/09
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Op 22 jul 2009, om 18:19 heeft Sanjeev Kumar Verma het volgende
geschreven:

>


> Rupesh,
> I got the way to Enable the neon support in the kernel in two steps -
> I run these command on the kernel make file
> 1. make omap3_beagle_android_defconfig
> 2. make menuconfig
> For enabling neon,
> Floating point emulation ---> select NEON Advanced SIMD Extension
> support and FastFPE math emulation (EXPERIMENTAL)

bzzzzt, wrong. The KConfig symbol you actually need was in my first
reply.

PGP.sig

Sanjeev Kumar Verma

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Jul 22, 2009, 12:29:31 PM7/22/09
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To build the kernel seperately if I type make for kernel I get "make:
arm-linux-gcc: Command not found
"
If I include another another toochain for this command I get the
error:-
error: #error Your version of gcc miscompiles the __weak directive
make[1]: *** [kernel/bounds.s] Error 1
make: *** [prepare0] Error 2

I don't know what to do?
Regards,
Sanjeev Kumar Verma

Sanjeev Kumar Verma

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Jul 23, 2009, 1:06:34 AM7/23/09
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Keon,
I did not understand. Please specify the steps clearly what to do to
enable the Neon support in my kernel.
Regards,
Sanjeev Kumar Verma
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> < 1KViewDownload

Steve C.

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Jul 24, 2009, 1:46:32 PM7/24/09
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I saw the same "illegal instruction" message on my console when
working with NEON until I reflashed the nand with the newest version
of the kernel.

On Jul 23, 1:06 am, Sanjeev Kumar Verma <sanjeev1...@gmail.com> wrote:
> Keon,
> I did not understand. Please specify the steps clearly what to do to
> enable theNeonsupport in my kernel.
> Regards,
> Sanjeev Kumar Verma
>
> On Jul 22, 9:29 pm, Koen Kooi <k...@beagleboard.org> wrote:
>
> > Op 22 jul 2009, om 18:19 heeft Sanjeev Kumar Verma het volgende  
> > geschreven:
>
> > > Rupesh,
> > > I got the way to Enable theneonsupport in the kernel in two steps -
> > > I run these command on the kernel make file
> > > 1. make omap3_beagle_android_defconfig
> > > 2. make menuconfig
> > > For enablingneon,
> > > Floating point emulation  ---> selectNEONAdvanced SIMD Extension

Jesslyn Abdul Salam

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Jul 24, 2009, 2:56:32 PM7/24/09
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In the linux omap kernel [assuming you have already done "make ARCH=arm omap3_beagle_defconfig]
make ARCH=arm menuconfig

Under the "Floating point emulation" Select "Advanced SIMD (NEON) Extension support".
Save the configuration and exit.

Check in the .config file whether you have "CONFIG_NEON=y"

- Jesslyn
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