Hi Rob, Geert, Marek, > -----Original Message----- > From: Marek Szyprowski [mailto:[email protected]] > Sent: Tuesday, March 06, 2018 12:06 AM > To: Geert Uytterhoeven <[email protected]>; Rob Herring > <[email protected]> > Cc: Jolly Shah <[email protected]>; Matthias Brugger > <[email protected]>; Andy Gross <[email protected]>; Shawn Guo > <[email protected]>; Geert Uytterhoeven <[email protected]>; > Björn Andersson <[email protected]>; [email protected]; > Michal Simek <[email protected]>; Mark Rutland > <[email protected]>; Rajan Vaja <[email protected]>; open list:OPEN > FIRMWARE AND FLATTENED DEVICE TREE BINDINGS > <[email protected]>; Linux ARM <linux-arm- > [email protected]>; Linux Kernel Mailing List <linux- > [email protected]>; Jolly Shah <[email protected]> > Subject: Re: [PATCH 1/2] dt-bindings: power: Add ZynqMP power domain > bindings > > Hi All, > > On 2018-03-06 08:59, Geert Uytterhoeven wrote: > > Hi Rob, Jolly, > > > > On Mon, Mar 5, 2018 at 11:39 PM, Rob Herring <[email protected]> wrote: > >> On Tue, Feb 27, 2018 at 03:55:49PM -0800, Jolly Shah wrote: > >>> Add documentation to describe ZynqMP power domain bindings. > >>> > >>> Signed-off-by: Jolly Shah <[email protected]> > >>> Signed-off-by: Rajan Vaja <[email protected]> > >>> --- > >>> .../devicetree/bindings/power/zynqmp-genpd.txt | 46 > ++++++++++++++++++++++ > >>> 1 file changed, 46 insertions(+) > >>> create mode 100644 > >>> Documentation/devicetree/bindings/power/zynqmp-genpd.txt > >>> > >>> diff --git > >>> a/Documentation/devicetree/bindings/power/zynqmp-genpd.txt > >>> b/Documentation/devicetree/bindings/power/zynqmp-genpd.txt > >>> new file mode 100644 > >>> index 0000000..25f9711 > >>> --- /dev/null > >>> +++ b/Documentation/devicetree/bindings/power/zynqmp-genpd.txt > >>> +This node contains a number of subnodes, each representing a single > >>> +PM domain that PM domain consumer devices reference. > >>> + > >>> +== PM Domain Nodes == > >>> + > >>> +Required properties: > >>> + - #power-domain-cells: Number of cells in a PM domain specifier. Must be > 0. > >>> + - pd-id: List of domain identifiers of as defined by platform firmware. > These > >>> + identifiers are passed to the PM firmware. > >>> + > >>> +Example: > >>> + zynqmp-genpd { > >>> + compatible = "xlnx,zynqmp-genpd"; > >> What's the control interface for controlling the domains? > >>> + > >>> + pd_usb0: pd-usb0 { > >>> + pd-id = <22>; > >>> + #power-domain-cells = <0>; > >> There's no need for all these sub nodes. Make #power-domain-cells 1 > >> and put the id in the cell value. > > That was my first reaction, too... > >>> + }; > >>> + > >>> + pd_sata: pd-sata { > >>> + pd-id = <28>; > >>> + #power-domain-cells = <0>; > >>> + }; > >>> + > >>> + pd_gpu: pd-gpu { > >>> + pd-id = <58 20 21>; > > ... until I saw the above. > > Controlling the GPU power area requires controlling 3 physical areas? > > > > However, doing it this way may bite you in the future, if a need > > arises to control a subset. And what about power up/down order? > > What about defining 3 separate domains and arranging them in parent-child > relationship? generic power domains already supports that and this allows to > nicely define the power on/off order. > > >>> + #power-domain-cells = <0x0>; > >>> + }; > >>> + }; >
I agree it should be arranged in as parent child order to control subset or control order. Will incorporate those changes in next version. > Best regards > -- > Marek Szyprowski, PhD > Samsung R&D Institute Poland
