Voltage for A7 Cluster at 1.5GHz too low

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Voltage for A7 Cluster at 1.5GHz too low #355

Open winstonyin opened 6 years ago

winstonyin commented 6 years ago

Reference: https://forum.odroid.com/viewtopic.php?f=99&t=31190

With linux-odroid-xu3 4.14.47-1 on Odroid XU4, the machine completely freezes or abruptly reboots (similar to power interruption) when the A7 cluster is running at 1.5GHz. Problem is resolved when maximum frequency is set at 1.4GHz or below.

The most recent commit of arch/arm/boot/dts/exynos5800.dtsi decreases the opt voltage for 1.5GHz by 62.5mV. This is suspected as the source of this instability.

moonlinux commented 6 years ago

Please share this input on the forum thread.

noapex commented 4 years ago

Had the same problem with a cluster of 12 XU 4, had to set max frequency to 1.4GHz to stop freezing. One curious thing: some boards (4 out of 12) were not affected by this issue and they have same power source, same os, etc. It would be great to be able to set it back to 1.5GHz.