Re: [PATCH] clk: meson: meson8b: Don't use MPLL1 as parent of vclk_in_sel

From: Jerome Brunet
Date: Mon May 24 2021 - 06:58:05 EST



On Mon 24 May 2021 at 12:45, Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx> wrote:

> MPLL1 is needed for audio output. Drop it from the vclk_in_sel parent
> list so we only use the (mutable) vid_pll_final_div tree or one of the
> (fixed) FCLK_DIV{3,4,5} clocks.

Are the fixed ones actually needed ?

If the consumer actually lives on the vid_pll only, I'd prefer if you
could add CLK_SET_RATE_NOREPARENT and assign the proper parent in DT with
`assigned-clock-parents`

>
> Signed-off-by: Martin Blumenstingl <martin.blumenstingl@xxxxxxxxxxxxxx>
> ---
> drivers/clk/meson/meson8b.c | 5 ++++-
> 1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/clk/meson/meson8b.c b/drivers/clk/meson/meson8b.c
> index a844d35b553a..f8bd211db720 100644
> --- a/drivers/clk/meson/meson8b.c
> +++ b/drivers/clk/meson/meson8b.c
> @@ -1154,6 +1154,10 @@ static struct clk_regmap meson8b_vid_pll_final_div = {
> },
> };
>
> +/*
> + * parent 0x6 is meson8b_mpll1 but we don't use it here because it's reserved
> + * for the audio outputs.
> + */
> static const struct clk_hw *meson8b_vclk_mux_parent_hws[] = {
> &meson8b_vid_pll_final_div.hw,
> &meson8b_fclk_div4.hw,
> @@ -1161,7 +1165,6 @@ static const struct clk_hw *meson8b_vclk_mux_parent_hws[] = {
> &meson8b_fclk_div5.hw,
> &meson8b_vid_pll_final_div.hw,
> &meson8b_fclk_div7.hw,
> - &meson8b_mpll1.hw,
> };
>
> static struct clk_regmap meson8b_vclk_in_sel = {