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+--- Forum: General Discussion on ROCK64 (https://forum.pine64.org/forumdisplay.php?fid=86)
+--- Thread: Rock64 power consumption (/showthread.php?tid=4818)
RE: Rock64 power consumption - ayufan - 01-16-2018
I'm not aware of having an ability to disable GPU, but given that it barely uses any resources if it is not being used it will make a negligible difference. You will probably achieve more with using a better power adapter with higher efficiency.
RE: Rock64 power consumption - z4v4l - 01-16-2018
how about clock gating it? rockchip SoCs have loads of clock gating registers for literally everything. CRU_CLKGATE_CON6 and CRU_CLKGATE_CON14 mention gpu.
RE: Rock64 power consumption - Exec - 01-16-2018
(01-16-2018, 02:48 PM)z4v4l Wrote: how about clock gating it? rockchip SoCs have loads of clock gating registers for literally everything. CRU_CLKGATE_CON6 and CRU_CLKGATE_CON14 mention gpu.
That sounds interesting.
Till now if have not much experience with such low level stuff in a "high level" OS.
I am more used to application programming or µC programming (like STM32F4 / F7). At the second most times peripheral gets only activated when it should be used so clock gets enabled.
But maybe with a SOC and a high level OS, in contrast to a µC, typically all "periherals" are/get activated by default.
Are all the "peripherals" activated / clocks enabled with a typical linux image for the Rock64?
In Chapter 2.8.5 on page 125 in the reference manual for HDMI it is described what "setup" is needed so that the peripheral gets its clock.
For clock gating the default/reset value is 0, what meens that clock gating is disabled. So e.g. for HDMI usage default behavoir should be that it is enabled.
Does someone know if clock gating could only be set during initialization, or is there also a dynamic access from user space?
RE: Rock64 power consumption - z4v4l - 01-17-2018
Quote:Does someone know if clock gating could only be set during initialization, or is there also a dynamic access from user space?I am not a linux guy, can't help with this. Of course it might be accessible (indirectly) or not. It can be set dynamically at anytime. The question is in exposing an interface for this by the OS.