Official sunxi OpenEmbedded layer for Allwinner-based boards.
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Koen Kooi 944e8111b8 machines: sync u-boot config name with boards.cfg
Recent u-boots (e.g. 2014.04-rc) need the _config appended to work, so
add that and sync the names with boards.cfg as well.

Signed-off-by: Koen Kooi <koen@dominion.thruhere.net>
2014-04-12 19:14:36 +02:00
classes sdcard_image-sunxi.bbclass: make sunxi-sdimg image dependent on rootfs type 2014-03-06 00:39:47 +11:00
conf machines: sync u-boot config name with boards.cfg 2014-04-12 19:14:36 +02:00
recipes-bsp Added Olinuxino A10 LIME 2014-03-07 16:05:47 +01:00
recipes-graphics Update libump: remove PE 2014-04-11 07:49:41 +02:00
recipes-kernel/linux linux 3.4: update to latest git 2014-04-08 09:55:42 +02:00
recipes-multimedia/gstreamer gst-plugin-cedar: import PoC gstreamer 0.10 plugin 2014-01-16 13:52:23 +01:00
recipes-support/sunxi-tools sunxi-tools: Fix build of sunxi-tools-native 2013-10-25 14:18:12 +02:00
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