From mboxrd@z Thu Jan 1 00:00:00 1970 From: Geert Uytterhoeven Subject: Re: [RFC PATCH 0/4] PM / Domains: Add support for explicit control of PM domains Date: Wed, 26 Apr 2017 10:06:20 +0200 Message-ID: References: <1490710443-27425-1-git-send-email-jonathanh@nvidia.com> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: In-Reply-To: Sender: linux-pm-owner@vger.kernel.org To: Ulf Hansson Cc: Jon Hunter , "Rafael J . Wysocki" , Kevin Hilman , Rajendra Nayak , Stanimir Varbanov , Stephen Boyd , Marek Szyprowski , "linux-pm@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-tegra@vger.kernel.org" List-Id: linux-tegra@vger.kernel.org Hi Ulf, On Tue, Apr 25, 2017 at 9:34 PM, Ulf Hansson wrote: > However, we currently know about at least two different SoCs that need > this. Perhaps we can extend the below list to justify adding a new > framework/APIs. Something along the lines what you propose in $subject > patchset. > > 1) Nvidia; to solve the USB super-speed host/device problem. > 2) QCOM, which has pointed to several cases where the PM topology is > laid out like devices having two PM domains.. > 3?) I don't fully remember - but I think Geert also pointed to some > examples where a device could reside in a clock domain but also in > power domain for a Renesas SoC!? > 4) ? Most Renesas SoCs have module clocks, which we model as a clock domain. Some Renesas SoCs have power domains for CPUs, others have them for devices as well. As we always provide a virtual "always-on" power domain in the power domain controller, all devices can refer to it using "power-domains" properties, and the driver for the power domain controller can just forward the clock domain operations to the clock driver. Gr{oetje,eeting}s, Geert -- Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org In personal conversations with technical people, I call myself a hacker. But when I'm talking to journalists I just say "programmer" or something like that. -- Linus Torvalds