[PATCH] clk: rockchip: add critical clock for rk3368

[heiko@sntech.de (Heiko Stübner)]

Am Montag, 14. September 2015, 15:19:21 schrieb Mark Rutland:
> On Sun, Sep 13, 2015 at 12:20:36PM +0100, Heiko St?bner wrote:
> > Again a result of the gpio-clock-liberation the rk3368 needs the
> > pclk_pd_pmu marked as critical, to boot successfully.
> > 
> > Reported-by: Mark Rutland <mark.rutland@arm.com>
> > Signed-off-by: Heiko Stuebner <heiko@sntech.de>
> 
> FWIW: Tested-by: Mark Rutland <mark.rutland@arm.com>
> 
> I'm surprised that we don't describe these as critical in the DT, given
> that this isn't really an internal property of the clock controller, but
> rather what happens to be attached to it. That ship appears to have
> sailed, however.

I wouldn't necessarily think so ... what is called critical only means "don't 
turn off when walking the clock-tree upwards".

The pclk_pd_pmu for example simply supplies some more clocks we don't handle 
at all currently (pclk_pmu_noc, ...). That we currently choose to ignore those 
[because we don't have any code nor dt-bindings to handle the components 
supplied] sounds very much like an implementation-specific detail, not 
something about the hardware.

I really like the concept of critical clock handling Mike is working on, which 
implements some sort of hand-off and keeps so marked clocks on until a real 
components picks them up.