TS-4300 Enable LD

The CPU Low Power Mode is controlled by the imx93-lpm driver through /sys/devices/platform/imx93-lpm/mode

The lpm mode supports 4 modes, 0-3, but only 0 (overdrive) and 3 (low drive) modes are currently supported. To see what mode you are in:

root@tsimx9:~# cat /sys/devices/platform/imx93-lpm/mode 
System is in OD mode with DDR 3200 MTS!

To switch to LD/SWFFC mode:

root@tsimx9:~# echo 3 > /sys/devices/platform/imx93-lpm/mode
[  410.931987] System switching to LD/SWFFC mode...
root@tsimx9:~# cat /sys/devices/platform/imx93-lpm/mode
System is in LD mode with DDR 625 MTS!

CPU and RAM speeds are decreased in Low Drive mode to save power without going to sleep. See Power Consumption for expected power savings and Sleep Mode for details on light and deep sleep modes.