Re: [PATCH] clk: rockchip: rk3288: prefer vdpu for vcodec clock source
From: Heiko Stuebner
Date: Sun May 14 2017 - 11:06:47 EST
Hi Randy,
Am Sonntag, 14. Mai 2017, 14:50:09 CEST schrieb Randy Li:
> The RK3288 CRU system clock solution would suggest use
> the vdpu clock source for the VPU(aclk_vpu and hclk_vpu).
>
> Reading the registers of VPU(both VEPU and VDPU) would become all high
> when the vepu is used as the clock source. It may be a bug in the SoC,
> not sure whether it is fixed at RK3288W.
I don't think that is a case of "preference". GRF_SOC_CON0[7] indicates
that value 0 means vepu gets selected as vcodec clock and value 1 means
vdpu gets selected as vcodec.
The array values below are supposed to match these values, so array
index 0 represents the clock for value 0 and so on. So this is really only
a description of the hardware clock layout.
If you want to actually switch the mux value, please assign the vcodec
clock an id and use the assigned-clocks mechanism in the devicetree.
Heiko