Re: [PATCH v3 12/17] clk: mediatek: mt8365-mm: fix DPI0 parent

[AngeloGioacchino Del Regno]

Il 18/04/24 16:17, Alexandre Mergnat ha scritto:
> To have a working display through DPI, a workaround has been
> implemented downstream to add "mm_dpi0_dpi0" and "dpi0_sel" to
> the DPI node. Shortly, that add an extra clock.
>
> It seems consistent to have the "dpi0_sel" as parent.
> Additionnaly, "vpll_dpix" isn't used/managed.
>
> Then, set the "mm_dpi0_dpi0" parent clock to "dpi0_sel".
>
> The new clock tree is:
>
> clk26m
>    lvdspll
>      lvdspll_X (2, 4, 8, 16)
>        dpi0_sel
>          mm_dpi0_dpi0
>
> Fixes: d46adccb7966 ("clk: mediatek: add driver for MT8365 SoC")
> Signed-off-by: Alexandre Mergnat <amergnat@xxxxxxxxxxxx>

I wonder what CLK_TOP_VPLL_DPIX_EN is for, but since you've ruled it out
by removing the dependency, this clock is 100% being disabled because unused
and the DPI interface clearly still works.

I also wonder if that clock is getting en/disabled by HW control mechanism...
..because that'd make sense, as this is .. well, a DPI clock.

That's just out of curiosity though, as I'd really like to understand whenwhatwhy
for stuff....

In any case, whether you have an answer or not, this commit is:

Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@xxxxxxxxxxxxx>

Cheers!