[PATCH 2/3] clk: sunxi-ng: a64: keep tcon0 clock rate when pll-video0's rate changes

[Icenowy Zheng]

在 2023-08-07星期一的 11:48 +0200，Frank Oltmanns写道：
> 
> On 2023-08-07 at 17:43:52 +0800, Icenowy Zheng <uwu at icenowy.me>
> wrote:
> > 在 2023-08-07星期一的 11:36 +0200，Frank Oltmanns写道：
> > > From: Icenowy Zheng <icenowy at aosc.io>
> > > 
> > > Notify TCON0 clock (and in consequence PLL-MIPI by
> > > CLK_SET_RATE_PARENT)
> > > to reset when PLL-Video0 changes (because of HDMI PHY clk which
> > > is a
> > > child of PLL-Video0 and has CLK_SET_RATE_PARENT set). In this way
> > > we
> > > can
> > > get clock tree to satisfy both pipelines.
> > 
> > Well for fixing one's patch that contains SoB, use the following
> > format:
> > 
> > Signed-off-by: A <a at a.local>
> > [B: fixed something]
> > Signed-off-by: B <b at b.local>
> 
> Ah, okay. Will do. But I keep A in the "From: " line, correct?

Yes.

> 
> Thanks,
>   Frank
> 
> > > ---
> > >  drivers/clk/sunxi-ng/ccu-sun50i-a64.c | 15 +++++++++++++++
> > >  1 file changed, 15 insertions(+)
> > > 
> > > diff --git a/drivers/clk/sunxi-ng/ccu-sun50i-a64.c
> > > b/drivers/clk/sunxi-ng/ccu-sun50i-a64.c
> > > index ef567775fc95..93beedb0428e 100644
> > > --- a/drivers/clk/sunxi-ng/ccu-sun50i-a64.c
> > > +++ b/drivers/clk/sunxi-ng/ccu-sun50i-a64.c
> > > @@ -943,6 +943,17 @@ static struct ccu_mux_nb sun50i_a64_cpu_nb =
> > > {
> > >         .bypass_index   = 1, /* index of 24 MHz oscillator */
> > >  };
> > >  
> > > +/*
> > > + * Since PLL-Video0 is an ancestor of both tcon0 and HDMI PYH,
> > > tcon0
> > > clock will
> > > + * conflict with HDMI PHY clock which is on another display
> > > pipeline.
> > > + *
> > > + * Therefore, a notifier is required to restore the rate of
> > > TCON0
> > > when the rate
> > > + * of PLL-Video0 changed.
> > > + */
> > > +static struct ccu_rate_reset_nb
> > > sun50i_a64_pll_video0_reset_tcon0_nb
> > > = {
> > > +       .common         = &pll_video0_clk.common,
> > > +};
> > > +
> > >  static int sun50i_a64_ccu_probe(struct platform_device *pdev)
> > >  {
> > >         void __iomem *reg;
> > > @@ -978,6 +989,10 @@ static int sun50i_a64_ccu_probe(struct
> > > platform_device *pdev)
> > >         ccu_mux_notifier_register(pll_cpux_clk.common.hw.clk,
> > >                                   &sun50i_a64_cpu_nb);
> > >  
> > > +       /* Reset the rate of TCON0 clock when PLL-VIDEO0 is
> > > changed
> > > */
> > > +       sun50i_a64_pll_video0_reset_tcon0_nb.target_clk =
> > > tcon0_clk.common.hw.clk;
> > > +       ccu_rate_reset_notifier_register(&sun50i_a64_pll_video0_r
> > > eset
> > > _tcon0_nb);
> > > +
> > >         return 0;
> > >  }
> > >  
> > >