arm-defaults.inc: don't enforce thumb for armv7a machines

[andrey-konovalov]

For armv7a arm_tune_handler() enforces not only hard-float, but
also thumb. But the comment for this function doesn't say that
RPB must use thumb, so the current implementation is more restrictive
than it should be.

Signed-off-by: Andrey Konovalov [email protected]

[andrey-konovalov]

I have a case when disabling thumb is necessary - https://projects.linaro.org/browse/MMWG-79 :
with a master-based build, on Beagle X15 I am getting illegal instruction in ff_h264_idct_dc_add_neon() (when trying to play h264 video with gstreamer). The disabling thumb helps.

Interesting, that there is no such problem in rocko-based build, as in the rocko case tha packages are armv7ahf-neon vs armv7at2hf-neon in the master-based build. Even though in the both cases TUNE_FEATURES="arm armv7a vfp thumb neon callconvention-hard".

[andrey-konovalov]

RE "All checks have failed": this is due to libxcrypt_4.4.1 do_configure failure - the current 96boards-reference-platform-openembedded-master builds are failing for the same reason. The premerge build for master branch uses db410c, db820c, hikey, and hikey960. All the four are aarch64 (DEFAULTTUNE="aarch64", TUNE_FEATURES="aarch64"), so this patch doesn't affect them at all.

[koenkooi]

Why no disable thumb in the offending recipe instead of doing it globally?

e.g. ARM_INSTRUCTION_SET_armv7a = "arm" in ffmpeg.bbappend

[andrey-konovalov]

OK, thank you!
I've created a new pull request (as the old branch name doesn't match the new implementation): #210

Closing this one.