Official sunxi OpenEmbedded layer for Allwinner-based boards.
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Kristof Robot 9a2692fcde sdcard_image-sunxi.bbclass: adding ext3 dependency (resolves #46)
Without this explicit dependency,
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Based on meta-raspberrypi commit a760ea5fa2
2014-03-04 22:37:31 +01:00
classes sdcard_image-sunxi.bbclass: adding ext3 dependency (resolves #46) 2014-03-04 22:37:31 +01:00
conf kernel-modules to include are now defined in sunxi.inc 2014-02-12 20:40:02 +01:00
recipes-bsp u-boot: fix PV 2014-02-14 13:23:25 +01:00
recipes-graphics xf86-video-fbturbo: fix PE 2014-02-18 13:02:15 +01:00
recipes-kernel/linux linux: run all defconfigs through 'make savedefconfig' 2014-02-23 08:44:58 +01:00
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COPYING.MIT allwinner-a10: initial import. 2012-06-03 19:47:57 +02:00
README.md README.md: added performance options (resolves #25) 2014-02-03 18:37:56 +01:00

meta-sunxi

Official sunxi OpenEmbedded layer for Allwinner-based boards.

This layer depends on the additional layer:

meta-openembedded: git://git.openembedded.org/meta-openembedded

Tested with core-image-base.

Maintainers:

Performance

The default machine settings are meant to be the lowest common denominator, maximizing generality. Significantly better performance (2x-3x) can be achieved with the following settings:

Allwinner A20

For Allwinner A20 (Cubieboard2/CubieTruck), the following tuning options are recommended:

Enable hardfloat, thumb2 and neon capabilities

DEFAULTTUNE = "cortexa7hf-neon-vfpv4"

This tuning profile takes advantage of the Allwinner A20 hardfloat, neon and vfpv4 capabilities.

Change CPU governor to ondemand, and tune settings

echo ondemand > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
echo 336000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_min_freq
echo 912000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
#More aggressive
#echo 1008000 > /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
echo 40 > /sys/devices/system/cpu/cpufreq/ondemand/up_threshold
echo 200000 > /sys/devices/system/cpu/cpufreq/ondemand/sampling_rate

This code changes the default CPU governor from fantasy to ondemand, and tunes its settings, as recommended at http://linux-sunxi.org/Cpufreq

For additional discussion, see https://github.com/linux-sunxi/meta-sunxi/issues/25