Re: [PATCH v4 1/4] clk: sunxi-ng: a64: force select PLL_MIPI in TCON0 mux
From: Jernej Škrabec
Date: Wed May 10 2023 - 14:43:37 EST
Dne petek, 05. maj 2023 ob 07:21:07 CEST je Roman Beranek napisal(a):
> TCON0's source clock can be fed from either PLL_MIPI, or PLL_VIDEO0(2X),
> however MIPI DSI output only seems to work when PLL_MIPI is selected and
> thus the choice must be hardcoded in.
>
> Currently, this driver can't propagate rate change from N-K-M clocks
> (such as PLL_MIPI) upwards. This prevents PLL_VIDEO0 from participating
> in setting of the TCON0 data clock rate, limiting the precision with
> which a target pixel clock can be matched.
>
> For outputs with fixed TCON0 divider, that is DSI and LVDS, the dotclock
> can deviate up to 8% off target.
>
> Signed-off-by: Roman Beranek <me@xxxxxxx>
Reviewed-by: Jernej Skrabec <jernej.skrabec@xxxxxxxxx>
Best regards,
Jernej