3.9.3. Rogue power management info

Rogue graphics drivers have supported active power management on AXE devices since TISDK release 8.6 and 8XE/BXS devices since release 9.0 with some discrepancy in the implementation between cores.

3.9.3.1. Active power management

In devices running a AXE core there is only one power domain for the GPU.

All interactions require the “core” power domain to be up. Linux controls this domain through the Active Power Management (APM) hooks in the kernel module. This domain remains online for all transactions and is offline after an idle period.

Enabled by default, APM allows modification at runtime through the devices /sys/devices/path_to_device/power/control interface. Reading the device file returns the current setting.

3.9.3.2. Suspend and resume

Suspend and resume features are also enabled for Rogue cores. The following procedure will test this on products supporting full device suspend and resume features:

Start a task to wake up the GPU by using glmark2:

# glmark2-es2-wayland &

Trigger a suspend event with a scheduled wake-up:

# rtcwake -s 3 -m mem

Wait for the scheduled wake-up.

The earlier sequence should result in the background compute task pausing during the suspend action and then resuming after the scheduled wake-up 3 seconds later.

Note

Driver specific unit tests (such as rgx_compute_test) will hold the device in the powered on state starting with driver version 24.1. You cannot use these tests as a load when attempting to test suspend and resume functionality.