From mboxrd@z Thu Jan 1 00:00:00 1970 From: khilman@kernel.org (Kevin Hilman) Date: Thu, 20 Nov 2014 17:30:53 -0800 Subject: [PATCH v4 1/2] ARM: keystone: pm: switch to use generic pm domains In-Reply-To: (Geert Uytterhoeven's message of "Thu, 20 Nov 2014 22:54:07 +0100") References: <1415631557-22897-1-git-send-email-grygorii.strashko@ti.com> <1709760.E0jX3Myv0h@wuerfel> <546C7FDD.7030906@ti.com> <2900095.WIocOu7ue2@wuerfel> <546DD87B.3080806@ti.com> <546E0970.5090301@ti.com> <7hh9xtr5ac.fsf@deeprootsystems.com> <7hbno1r1af.fsf@deeprootsystems.com> Message-ID: <7hppchpcfm.fsf@deeprootsystems.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Geert Uytterhoeven writes: > On Thu, Nov 20, 2014 at 10:48 PM, Kevin Hilman wrote: >>>> So what exactly are we talking about with "PM" clocks, and why are they >>>> "special" when it comes to PM domains? IOW, why are the clocks to be >>>> managed during PM domain transitions for a given device any different >>>> than the clocks that need to be managed for a runtime suspend/resume (or >>>> system suspend/resume) sequence for the same device? >>> >>> (Speaking for my case, shmobile) >>> >>> They're not. The clocks to be managed during PM domain transitions are the >>> same as the clocks that need to be managed for a runtime suspend/resume >>> (or system suspend/resume) sequence. >>> >>> The special thing is that this is more a platform than a driver thing: the same >>> module may have a "PM/functional" clock (that is documented to enable/disable >>> the module) on one Soc, but noet on another. >> >> So why isn't the presence or absence of the clock described in the .dtsi >> for the SoC instead of being handled by special PM domain logic? > > It is. Cfr. the presence/absence of clocks for renesas,rcar-gpio nodes. Hmm, OK, Good. So now I'm confused about why the PM domain has to do anything special if the presence/absence of the clocks is already handled by the DT. Kevin