From mboxrd@z Thu Jan 1 00:00:00 1970 From: Krzysztof Kozlowski Subject: Re: [PATCH v2 09/19] PM / devfreq: exynos: Update documentation for bus devices using passive governor Date: Thu, 10 Dec 2015 10:31:09 +0900 Message-ID: References: Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: In-reply-to: Sender: linux-samsung-soc-owner@vger.kernel.org To: Chanwoo Choi , myungjoo.ham@samsung.com, kgene@kernel.org Cc: kyungmin.park@samsung.com, robh+dt@kernel.org, pawel.moll@arm.com, mark.rutland@arm.com, ijc+devicetree@hellion.org.uk, galak@codeaurora.org, linux@arm.linux.org.uk, tjakobi@math.uni-bielefeld.de, linux.amoon@gmail.com, linux-kernel@vger.kernel.org, linux-pm@vger.kernel.org, linux-samsung-soc@vger.kernel.org, devicetree@vger.kernel.org List-Id: devicetree@vger.kernel.org List-Archive: On 09.12.2015 13:08, Chanwoo Choi wrote: > This patch updates the documentation for passive bus devices and adds the > detailed example of Exynos3250. > > Signed-off-by: Chanwoo Choi > — > …/devicetree/bindings/devfreq/exynos-bus.txt | 244 ++++++++++++++++++++- > 1 file changed, 241 insertions(+), 3 deletions(-) > > diff –git a/Documentation/devicetree/bindings/devfreq/exynos-bus.txt b/Documentation/devicetree/bindings/devfreq/exynos-bus.txt > index 54a1f9c46c88..c4fdc70f8eac 100644 > — a/Documentation/devicetree/bindings/devfreq/exynos-bus.txt > +++ b/Documentation/devicetree/bindings/devfreq/exynos-bus.txt > @@ -13,18 +13,23 @@ SoC has the different sub-blocks. So, this difference should be specified > in devicetree file instead of each device driver. In result, this driver > is able to support the bus frequency for all Exynos SoCs. > > -Required properties for bus device: > +Required properties for all bus devices: > – compatible: Should be “samsung,exynos-bus”. > – clock-names : the name of clock used by the bus, “bus”. > – clocks : phandles for clock specified in “clock-names” property. > – #clock-cells: should be 1. > – operating-points-v2: the OPP table including frequency/voltage information > to support DVFS (Dynamic Voltage/Frequency Scaling) feature. > + > +Required properties for only parent bus device: Maybe: “Required properties only for parent bus devices:” In this binding documentation file the idea of “parent” is not explained. I now it is related to passive devfreq governor but looking at the binding itself it is a new idea, not covered here. > – vdd-supply: the regulator to provide the buses with the voltage. > – devfreq-events: the devfreq-event device to monitor the curret utilization > of buses. > > -Optional properties for bus device: > +Required properties for only passive bus device: “Required properties only for passive bus devices:” > +- devfreq: the parent bus device. > + > +Optional properties for only parent bus device: > – exynos,saturation-ratio: the percentage value which is used to calibrate > the performance count againt total cycle count. > > @@ -33,7 +38,20 @@ Example1: > power line (regulator). The MIF (Memory Interface) AXI bus is used to > transfer data between DRAM and CPU and uses the VDD_MIF regualtor. > > – – power line(VDD_MIF) –> bus for DMC (Dynamic Memory Controller) block > + – MIF (Memory Interface) block > + : VDD_MIF |— DMC (Dynamic Memory Controller) > + > + – INT (Internal) block > + : VDD_INT |— LEFTBUS (parent device) > + |— PERIL > + |— MFC > + |— G3D > + |— RIGHTBUS > + |— FSYS > + |— LCD0 > + |— PERIR > + |— ISP > + |— CAM > > – MIF bus’s frequency/voltage table > ———————– > @@ -46,6 +64,24 @@ Example1: > |L5| 400000 |875000 | > ———————– > > + – INT bus’s frequency/voltage table > + ———————————————————- > + |Block|LEFTBUS|RIGHTBUS|MCUISP |ISP |PERIL ||VDD_INT | > + | name| |LCD0 | | | || | > + | | |FSYS | | | || | > + | | |MFC | | | || | > + ———————————————————- > + |Mode |*parent|passive |passive|passive|passive|| | > + ———————————————————- > + |Lv |Frequency ||Voltage | > + ———————————————————- > + |L1 |50000 |50000 |50000 |50000 |50000 ||900000 | > + |L2 |80000 |80000 |80000 |80000 |80000 ||900000 | > + |L3 |100000 |100000 |100000 |100000 |100000 ||1000000 | > + |L4 |134000 |134000 |200000 |200000 | ||1000000 | > + |L5 |200000 |200000 |400000 |300000 | ||1000000 | > + ———————————————————- > + > Example2 : > The bus of DMC (Dynamic Memory Controller) block in exynos3250.dtsi > are listed below: > @@ -84,6 +120,167 @@ Example2 : > }; > }; > > + bus_leftbus: bus_leftbus { > + compatible = “samsung,exynos-bus”; > + clocks = ; > + clock-names = “bus”; > + operating-points-v2 = ; > + status = “disabled”; > + }; > + > + bus_rightbus: bus_rightbus { > + compatible = “samsung,exynos-bus”; > + clocks = ; > + clock-names = “bus”; > + operating-points-v2 = ; > + status = “disabled”; > + }; > + > + bus_lcd0: bus_lcd0 { > + compatible = “samsung,exynos-bus”; > + clocks = ; > + clock-names = “bus”; > + operating-points-v2 = ; > + status = “disabled”; > + }; > + > + bus_fsys: bus_fsys { > + compatible = “samsung,exynos-bus”; > + clocks = ; > + clock-names = “bus”; > + operating-points-v2 = ; > + status = “disabled”; > + }; > + > + bus_mcuisp: bus_mcuisp { > + compatible = “samsung,exynos-bus”; > + clocks = ; > + clock-names = “bus”; > + operating-points-v2 = ; > + status = “disabled”; > + }; > + > + bus_isp: bus_isp { > + compatible = “samsung,exynos-bus”; > + clocks = ; > + clock-names = “bus”; > + operating-points-v2 = ; > + status = “disabled”; > + }; > + > + bus_peril: bus_perir { Peril or perir? Best regards, Krzysztof

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