Re: [PATCH] clk: x86: Do not gate clocks enabled by the firmware

[Stephen Boyd <sboyd@codeaurora.org>]

On 07/10, Darren Hart wrote:
> On Tue, Jul 11, 2017 at 12:31:28AM +0200, Enric Balletbo Serra wrote:
> > 2017-07-10 22:38 GMT+02:00 Carlo Caione <carlo@caione.org>:
> > >         pclk->reg = base + PMC_CLK_CTL_OFFSET + id * PMC_CLK_CTL_SIZE;
> > >         spin_lock_init(&pclk->lock);
> > >
> > > +       if (plt_clk_is_enabled(&pclk->hw))
> > > +               init.flags |= CLK_IGNORE_UNUSED;

Can you add a comment to the effect of why we're adding ignore
unused here? That will make it clearer when reading the code a
year from now why we're not turning these clks off by default and
also allow us to recall why it isn't marked as a critical clk.

Probably, we want some sort of handoff mechanism here so that the
clk is left on until a driver comes into the picture and acquires
a handle to this clk?

> > > +
> > >         ret = devm_clk_hw_register(&pdev->dev, &pclk->hw);
> > >         if (ret) {
> > >                 pclk = ERR_PTR(ret);
> > > --
> > > 2.13.2
> > >
> > 
> > It also fixes the issue introduced in commit 282a4e4 ("platform/x86:
> > Enable Atom PMC platform clocks") that causes no audio on Baytrail.
> > 
> > Tested-by: Enric Balletbo i Serra <enric.balletbo@collabora.com>
> 
> Excellent, thank you Enric. Pierre, any objections to this going in to
> 4.13 now and stable back to 4.12?
> 

You mean v4.11? That's when commit 282a4e4 was released.
Typically we punt these sorts of things to the next release
because it isn't a regression in the release that's being worked
on (i.e. it wasn't introduced in this merge window), but in this
case it seems like a small enough patch plus it's a bother to
keep it out of the release to make it alright to merge now.

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