On 10/28, Tony Lindgren wrote:

* Tero Kristo [off-list ref] [161028 00:43]:

quoted

On 28/10/16 03:50, Stephen Boyd wrote:

quoted

I suppose a PRCM is
like an MFD that has clocks and resets under it? On other
platforms we've combined that all into one node and just had
#clock-cells and #reset-cells in that node. Is there any reason
we can't do that here?

For OMAPs, there are typically multiple instances of the PRCM around; OMAP4
for example has:

cm1 @ 0x4a004000 (clocks + clockdomains)
cm2 @ 0x4a008000 (clocks + clockdomains)
prm @ 0x4a306000 (few clocks + resets + power state handling)
scrm @ 0x4a30a000 (few external clocks + plenty of misc stuff)

These instances are also under different power/voltage domains which means
their PM behavior is different.

The idea behind having a clockdomain as a provider was mostly to have the
topology visible : prcm-instance -> clockdomain -> clocks

Yeah that's needed to get the interconnect hierarchy right for
genpd :)

quoted

... but basically I think it would be possible to drop the clockdomain
representation and just mark the prcm-instance as a clock provider. Tony,
any thoughts on that?

No let's not drop the clockdomains as those will be needed when we
move things into proper hierarchy within the interconnect instances.
This will then help with getting things right with genpd.

In the long run we just want to specify clockdomain and the offset of
the clock instance within the clockdomain in the dts files.

Sorry, I have very little idea how OMAP hardware works. Do you
mean that you will have different nodes for each clockdomain so
that genpd can map 1:1 to the node in dts? But in hardware
there's a prcm that allows us to control many clock domains
through register read/writes? How is the interconnect involved?

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