On 12/07/2017 12:09, Viresh Kumar wrote:

On 12-07-17, 11:58, Mason wrote:

quoted

I would object to the characterization of "just a PLL" :-)

The PLL outputs "garbage" before actually "locking" a target
frequency. It is not possible for the CPU to blindly change
the PLL settings, because that crashes the system.

The bootloader implements the steps required to change said
settings, so the strategy has been: have Linux use whatever
PLL frequency the bootloader programs.

Behind the PLL, there is a glitch-free divider, which is able
to divide the PLL output without crashing the system. I've
been using that divider for DFS.

drivers/clk/clk-tango4.c

Okay, got it now.

Yes, you *really* need to create these OPPs dynamically.
I am convinced now :)

I will test your patch on my 4.9 branch.

Does tango-cpufreq.c look acceptable to you?
(I am aware the patch needs work in the the Kconfig/Makefile part.
That was quick and dirty.)

Regards.