Re: [PATCH v3 6/8] clk: tegra20: Turn EMC clock gate into divider

Dmitry Osipenko
2018-07-09T11:52:41Z

On Monday, 9 July 2018 03:00:17 MSK Stephen Boyd wrote:
> Quoting Dmitry Osipenko (2018-06-17 07:55:37)
>
> > Kernel should never gate the EMC clock as it causes immediate lockup, so
> > removing clk-gate functionality doesn't affect anything. Turning EMC clk
> > gate into divider allows to implement glitch-less EMC scaling, avoiding
> > reparenting to a backup clock.
> >
> > Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
> > Acked-by: Peter De Schrijver <pdeschrijver@nvidia.com>
> > ---
>
> Who's supposed to apply this? Me? Thierry? The "To:" line is not
> useful when every maintainer is there.

That's up to you and Thierry to decide. Perhaps it would be less churning if
you'll give your ack on the 'clk:' patches and Thierry will handle the whole
series on his own.

> > diff --git a/drivers/clk/tegra/clk-tegra20.c
> > b/drivers/clk/tegra/clk-tegra20.c index cc857d4d4a86..2bd35418716a 100644
> > --- a/drivers/clk/tegra/clk-tegra20.c
> > +++ b/drivers/clk/tegra/clk-tegra20.c
> > @@ -799,6 +798,31 @@ static struct tegra_periph_init_data
> > tegra_periph_nodiv_clk_list[] = {>
> > TEGRA_INIT_DATA_NODIV("disp2", mux_pllpdc_clkm, CLK_SOURCE_DISP2,
> > 30, 2, 26, 0, TEGRA20_CLK_DISP2),>
> > };
> >
> > +static void __init tegra20_emc_clk_init(void)
> > +{
> > + struct clk *clk;
> > +
> > + clk = clk_register_mux(NULL, "emc_mux", mux_pllmcp_clkm,
> > + ARRAY_SIZE(mux_pllmcp_clkm),
> > + CLK_SET_RATE_NO_REPARENT,
> > + clk_base + CLK_SOURCE_EMC,
> > + 30, 2, 0, &emc_lock);
> > +
> > + clk = tegra_clk_register_mc("mc", "emc_mux", clk_base +
> > CLK_SOURCE_EMC, + &emc_lock);
> > + clks[TEGRA20_CLK_MC] = clk;
> > +
> > + /*
> > + * Note that 'emc_mux' source and 'emc' rate shouldn't be changed
> > at + * the same time due to a HW bug, this won't happen because
> > we're + * defining 'emc_mux' and 'emc' as a distinct clocks.
>
> s/ a//

I can adjust the comment and re-spin the series if something more important
will pop up, otherwise that could addressed while applying the patch.