Re: [v2 1/4] ARM: tegra20: create a DT header defining CLK IDs

On 02/15/2013 02:24 AM, Peter De Schrijver wrote:

On Thu, Feb 14, 2013 at 09:15:28PM +0100, Stephen Warren wrote:

quoted

On 02/14/2013 11:59 AM, Hiroshi Doyu wrote:

quoted

To replace magic number in tegra_car:

-               clocks = <&tegra_car 28>;
+               clocks = <&tegra_car CLK_HOST1X>;

quoted

diff --git a/arch/arm/boot/dts/tegra20-car.h b/arch/arm/boot/dts/tegra20-car.h

Sorry, forgot a couple small comments the last time around.

This file should probably have some header indicating which binding it
describes, rather like the GPIO header in my patch series.

quoted

+#define CLK_CPU 0

I'd suggest naming that TEGRA20_CLK_CPU, so that the various different
clock headers don't conflict. It's not too likely that more than one of
the /Tegra/ clock headers will be included at once, but it doesn't seem
that unlikely that a board file could end up having a Tegra clock header
included plus various other clock headers for some other chip that has
some clock outputs.

I would suggest removing this clock. It's not actually implemented in the CCF
and rather useless. If you would gate the CPU clock from the CPU by writing to
this register, how would you ungate it? :) Note that this would gate the clock
to all CPUs.

(Note that my comment was re: all clocks, not just that one clock)

Can't the PMC or flow-controller ungate the clock based on some event?
Either way, that clock definition exists in HW, right? So I don't think
there's actually any harm in including the definition in the binding
even if we never implement/use it.