[PATCH 1/4] clk: rockchip: protect critical clocks from getting disabled

[Heiko Stübner]

Hi Mike,

Am Donnerstag, 31. Juli 2014, 15:45:23 schrieb Mike Turquette:
> Quoting Heiko Stuebner (2014-07-29 12:12:05)
> 
> > The clock-tree contains clocks that should never get disabled
> > automatically. One example are the base ACLKs, the base supplies for all
> > peripherals.
> > 
> > Therefore add a structure similar to the sunxi clock-tree to protect these
> > special clocks from being disabled.
> > 
> > Signed-off-by: Heiko Stuebner <heiko at sntech.de>
> > ---
> > 
> >  drivers/clk/rockchip/clk-rk3188.c |  7 +++++++
> >  drivers/clk/rockchip/clk-rk3288.c |  7 +++++++
> >  drivers/clk/rockchip/clk.c        | 13 +++++++++++++
> >  drivers/clk/rockchip/clk.h        |  1 +
> >  4 files changed, 28 insertions(+)
> > 
> > diff --git a/drivers/clk/rockchip/clk-rk3188.c
> > b/drivers/clk/rockchip/clk-rk3188.c index a83a6d8..5aef277 100644
> > --- a/drivers/clk/rockchip/clk-rk3188.c
> > +++ b/drivers/clk/rockchip/clk-rk3188.c
> > @@ -599,6 +599,11 @@ static struct rockchip_clk_branch
> > rk3188_clk_branches[] __initdata = {> 
> >         GATE(ACLK_GPS, "aclk_gps", "aclk_peri", 0, RK2928_CLKGATE_CON(8),
> >         13, GFLAGS),>  
> >  };
> > 
> > +static const char *rk3188_critical_clocks[] __initconst = {
> > +       "aclk_cpu",
> > +       "aclk_peri",
> 
> I'm not against the idea of critical clocks, but I want to verify that
> there is no other driver out there that is a better fit for claiming
> these clks via clk_get and enabling them the normal way via clk_enable?

In the clock hierarchy of Rockchip SoCs, both aclks listed here, are sources 
for pclk and hclk, as well as sourcing some other peripheral gates further 
below too. So from what I've seen from the clock diagrams, there is nothing 
that would claim these clocks directly, and it wouldn't also make any sense to 
let them get disabled as there will always be something using them (for 
example the dram-controller).


Heiko