[PATCH v2] ARM: dts: Add dts file for odroid XU3 board
Jonathan Stone -SISA
j.stone at samsung.com
Wed Jan 7 15:49:22 PST 2015
On On Wed, 2015-01-07 at 18:37 +0000, Sjoerd Simons writes wrote:
>On Wed, 2015-01-07 at 18:37 +0000, Anand Moon wrote:>
[...]
>> Only 4 core cpu's are on my board. Also CpuFreq is not working.
>
> Can you share some point on this.
>The defconfig is using the bL switcher, which pairs up big and little cores to make them appear as one core.. So for 8 real cores, you'll get
>4 "virtual cores".
That configuration is appropriate for the 5420, which allegedly has a hardware bug in the cache-coherence between the Cortex-A7 block and the Cortex-A15 block.
Newer Exynos 5 SoCs -- 5422/5800, 5620, etc -- don't have that bug. The scheduler should configured to do HMP on all 8 (or 6) cores.
I don't have a 5410, but I assume it has the same bug as the 5420.
The XU3 kernel supplied by HardKernel shows all 8 cores, and does HMP scheduling across all 8.
I tried v1.0 of the Odroid-XU3 DTB patch, applied to linux-next 20150107. I'm only seeing 1 core running on my Odroid-XU3. The USB 3.0 port works (great!) but I'm not getting any HDMI output. I didn't try DisplayPort. I'll gladly try v2 of the patch on an XU3; is there a better base to apply the patch to?
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