From mboxrd@z Thu Jan 1 00:00:00 1970 From: rnayak@codeaurora.org (Rajendra Nayak) Date: Mon, 27 Apr 2015 08:02:20 +0530 Subject: [PATCH v5 08/11] arm: dts: qcom: Add #power-domain-cells property In-Reply-To: References: <1429017137-20218-1-git-send-email-rnayak@codeaurora.org> <1429017137-20218-9-git-send-email-rnayak@codeaurora.org> <553A2106.1030102@codeaurora.org> Message-ID: <553D9FB4.6060107@codeaurora.org> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 04/24/2015 09:13 PM, Ulf Hansson wrote: > On 24 April 2015 at 12:55, Rajendra Nayak wrote: >> On 04/24/2015 03:15 PM, Ulf Hansson wrote: >>> >>> On 14 April 2015 at 15:12, Rajendra Nayak wrote: >>>> >>>> msm8974 has gcc and mmcc nodes, and apq8084 has a gcc node which >>>> implement gdsc powerdomains. Add the #power-domain-cells property >>>> to them. >>>> >>>> Signed-off-by: Rajendra Nayak >>>> --- >>>> arch/arm/boot/dts/qcom-apq8084.dtsi | 1 + >>>> arch/arm/boot/dts/qcom-msm8974.dtsi | 2 ++ >>>> 2 files changed, 3 insertions(+) >>>> >>>> diff --git a/arch/arm/boot/dts/qcom-apq8084.dtsi >>>> b/arch/arm/boot/dts/qcom-apq8084.dtsi >>>> index 1f130bc..55c281c 100644 >>>> --- a/arch/arm/boot/dts/qcom-apq8084.dtsi >>>> +++ b/arch/arm/boot/dts/qcom-apq8084.dtsi >>>> @@ -183,6 +183,7 @@ >>>> compatible = "qcom,gcc-apq8084"; >>>> #clock-cells = <1>; >>>> #reset-cells = <1>; >>>> + #power-domain-cells = <1>; >>> >>> >>> So the PM domain will be apart of the clock-controller. That's a bit >>> odd, but I guess the hardware is like that!? >> >> >> Yes, the gdscs are all part of GCC controller. >> >>> >>> Anyway, what I fail to understand from this patchset is who will be >>> the actual consumer of the PM domain? In other words, what devices >>> will hold the below property in its DT node? >>> >>> power_domains = ; >>> >>> This is needed for genpd to have the device at probe time, attached to >>> its PM domain. >> >> >> Any device which belongs to the collapsible power domain (gdsc) >> Examples are graphics, camera, video encode/decode block (venus) etc > > Then I expect those drivers to deploy runtime PM (if not already) and > thus gdsc's PM domain will come into play. Most of these drivers aren;t upstream yet. And one of the reasons I am trying to get gdsc support upstream is so these drivers can then be pushed upstream, with runtime support. > > But how will that relate to the GCC controller? > > For example when the gdsc's PM domain is about to be powered off, > since all the devices within it has be runtime PM suspended. What > happens with the GCC controller then? I don;t seem to completely understand what you are asking. Are you asking if the GCC controller itself is part of a collapsible power domain? > > Kind regards > Uffe > -- Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum, hosted by The Linux Foundation