Bug 5710

Summary: Add Cortex A7 support for "neon-vfpv4"
Product: [Build System, Metadata & Runtime] OE-Core Reporter: Krirobo <krirobo>
Component: configurationAssignee: Krirobo <krirobo>
Status: RESOLVED FIXED QA Contact:
Severity: enhancement    
Priority: Low CC: bluelightning, Martin.Jansa
Version: unspecified   
Target Milestone: Future   
Hardware: Other   
OS: arm   
Whiteboard:
OS type for building Yocto: --- Type of Regression: ---
Verified: Documentation change: No (bug/feature does not impact docs)

Description Krirobo 2014-01-09 16:01:02 UTC 
Current tune-cortexa7.inc file [1] does not support a tuning option for  '-mfpu=neon-vfpv4' (see [2] for more information on ARM compiler options).

Would it be possible to add this option?

My specific use case is a Cubieboard2 hardware, but this should be beneficial to the broader Cortex A7 community as well.

OpenEmbedded layer for this hardware is meta-sunxi ([3]).

Also, some related information can be found here: [4]

Thanks,

Kristof


[1] https://github.com/openembedded/oe-core/blob/master/meta/conf/machine/include/tune-cortexa7.inc
[2] http://gcc.gnu.org/onlinedocs/gcc/ARM-Options.html
[3] https://github.com/linux-sunxi/meta-sunxi
[4] https://wiki.linaro.org/WorkingGroups/ToolChain/FAQ#Does_Linaro_GCC_toolchain_support_Cortex-A7_along_with_NEONv2_.26_VFPv4.3F
Comment 1 Richard Purdie 2014-01-16 15:37:54 UTC 
The best way to handle this is to propose a patch. I don't know if this is a feature all A7 cores have or not but it would seem reasonable to make the tune available in some form. I'm assigning it to you to generate a patch and send it for review.
Comment 3 Martin Jansa 2015-10-06 13:16:31 UTC 
Why was this added only to hf tunes and only for A7 (not A15 and A17 which should also support this?)
Comment 4 Krirobo 2015-10-06 13:40:02 UTC 
Reason is simply that this patch was driven by a need on the Cubieboard2 hardware, and that I have very little knowledge and no experience beyond this hardware.

This probably could indeed be extended to other flavours as well.
Comment 5 Martin Jansa 2015-10-06 13:57:39 UTC 
I've sent patch to extend this:
http://lists.openembedded.org/pipermail/openembedded-core/2015-October/111318.html