dmc_ondemand downdifferential

[jimmyhon]

Regarding using a upthreshold of 20 vs 25. Have you considered lowering the downdifferential to get the memory frequency back down to idle?

With the default downdifferential of 20 [1], by changing the upthreshold to 20, governor will stay at the same frequency almost all the time once it's boosted up. [2] (i.e. upthreshold - downdifferential is 0, so the frequency will not drop unless busy_time is 0.)

1. https://gitlab.com/rk3588_linux/rk/kernel/-/blob/linux-5.10-gen-rkr3.6/arch/arm64/boot/dts/rockchip/rk3588s.dtsi#L1289-1290
2. https://gitlab.com/rk3588_linux/rk/kernel/-/blob/linux-5.10-gen-rkr3.6/drivers/devfreq/rockchip_dmc.c#L2810-2815