Ping...
Hi, Eduardo
Looks like we are going around in circle, can we make decision of which
direction to go?
Best Regards!
Anson Huang
> -----Original Message-----
> From: Anson Huang
> Sent: 2019年3月1日 9:41
> To: 'Rob Herring' <r...@kernel.org>; edubez...@gmail.com
> Cc: mark.rutl...@arm.com; shawn...@kernel.org;
> s.ha...@pengutronix.de; ker...@pengutronix.de; feste...@gmail.com;
> catalin.mari...@arm.com; will.dea...@arm.com; rui.zh...@intel.com;
> edubez...@gmail.com; daniel.lezc...@linaro.org; Aisheng Dong
> <aisheng.d...@nxp.com>; ulf.hans...@linaro.org; sb...@kernel.org;
> Daniel Baluta <daniel.bal...@nxp.com>; Andy Gross
> <andy.gr...@linaro.org>; horms+rene...@verge.net.au; he...@sntech.de;
> a...@arndb.de; maxime.rip...@bootlin.com; bjorn.anders...@linaro.org;
> ja...@amarulasolutions.com; enric.balle...@collabora.com;
> marc.w.gonza...@free.fr; o...@lixom.net; devicet...@vger.kernel.org;
> linux-kernel@vger.kernel.org; linux-arm-ker...@lists.infradead.org; linux-
> p...@vger.kernel.org; dl-linux-imx <linux-...@nxp.com>
> Subject: RE: [PATCH V10 1/4] dt-bindings: fsl: scu: add thermal binding
>
> Hi, Rob/Eduardo
>
> Best Regards!
> Anson Huang
>
> > -----Original Message-----
> > From: Rob Herring [mailto:r...@kernel.org]
> > Sent: 2019年2月28日 22:49
> > To: Anson Huang <anson.hu...@nxp.com>
> > Cc: mark.rutl...@arm.com; shawn...@kernel.org;
> s.ha...@pengutronix.de;
> > ker...@pengutronix.de; feste...@gmail.com; catalin.mari...@arm.com;
> > will.dea...@arm.com; rui.zh...@intel.com; edubez...@gmail.com;
> > daniel.lezc...@linaro.org; Aisheng Dong <aisheng.d...@nxp.com>;
> > ulf.hans...@linaro.org; sb...@kernel.org; Daniel Baluta
> > <daniel.bal...@nxp.com>; Andy Gross <andy.gr...@linaro.org>;
> > horms+rene...@verge.net.au; he...@sntech.de; a...@arndb.de;
> > maxime.rip...@bootlin.com; bjorn.anders...@linaro.org;
> > ja...@amarulasolutions.com; enric.balle...@collabora.com;
> > marc.w.gonza...@free.fr; o...@lixom.net; devicet...@vger.kernel.org;
> > linux-kernel@vger.kernel.org; linux-arm-ker...@lists.infradead.org;
> > linux- p...@vger.kernel.org; dl-linux-imx <linux-...@nxp.com>
> > Subject: Re: [PATCH V10 1/4] dt-bindings: fsl: scu: add thermal
> > binding
> >
> > On Wed, Feb 27, 2019 at 6:48 PM Anson Huang <anson.hu...@nxp.com>
> > wrote:
> > >
> > > Hi, Rob
> > >
> > > Best Regards!
> > > Anson Huang
> > >
> > > > -----Original Message-----
> > > > From: Rob Herring [mailto:r...@kernel.org]
> > > > Sent: 2019年2月28日 7:55
> > > > To: Anson Huang <anson.hu...@nxp.com>
> > > > Cc: mark.rutl...@arm.com; shawn...@kernel.org;
> > > > s.ha...@pengutronix.de; ker...@pengutronix.de;
> feste...@gmail.com;
> > > > catalin.mari...@arm.com; will.dea...@arm.com;
> rui.zh...@intel.com;
> > > > edubez...@gmail.com; daniel.lezc...@linaro.org; Aisheng Dong
> > > > <aisheng.d...@nxp.com>; ulf.hans...@linaro.org; sb...@kernel.org;
> > > > Daniel Baluta <daniel.bal...@nxp.com>; Andy Gross
> > > > <andy.gr...@linaro.org>; horms+rene...@verge.net.au;
> > > > he...@sntech.de; a...@arndb.de; maxime.rip...@bootlin.com;
> > > > bjorn.anders...@linaro.org; ja...@amarulasolutions.com;
> > > > enric.balle...@collabora.com; marc.w.gonza...@free.fr;
> > > > o...@lixom.net; devicet...@vger.kernel.org;
> > > > linux-kernel@vger.kernel.org;
> > > > linux-arm-ker...@lists.infradead.org;
> > > > linux- p...@vger.kernel.org; dl-linux-imx <linux-...@nxp.com>
> > > > Subject: Re: [PATCH V10 1/4] dt-bindings: fsl: scu: add thermal
> > > > binding
> > > >
> > > > On Wed, Feb 27, 2019 at 08:46:21AM +0000, Anson Huang wrote:
> > > > > NXP i.MX8QXP is an ARMv8 SoC with a Cortex-M4 core inside as
> > > > > system controller, the system controller is in charge of system
> > > > > power, clock and thermal sensors etc. management, Linux kernel
> > > > > has to communicate with system controller via MU (message unit)
> > > > > IPC to get temperature from thermal sensors, this patch adds
> > > > > binding doc for i.MX system controller thermal driver.
> > > > >
> > > > > Signed-off-by: Anson Huang <anson.hu...@nxp.com>
> > > > > ---
> > > > > Changes since V9:
> > > > > - change #thermal-sensor-cells value in example to 1, since
> > > > > there are
> > > > other
> > > > > thermal sensors inside system controller, it is just
> > > > > because there are
> > > > still
> > > > > some issue, so system controller does NOT expose them for
> > > > > now,
> > > > they could
> > > > > be exposed later, so it should be 1 from HW perspective.
> > > > > ---
> > > > > .../devicetree/bindings/arm/freescale/fsl,scu.txt | 21
> > > > +++++++++++++++++++++
> > > > > 1 file changed, 21 insertions(+)
> > > > >
> > > > > diff --git
> > > > > a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > > > > b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > > > > index 72d481c..855270b 100644
> > > > > ---
> > > > > a/Documentation/devicetree/bindings/arm/freescale/fsl,scu.txt
> > > > > +++ b/Documentation/devicetree/bindings/arm/freescale/fsl,scu.tx
> > > > > +++ t
> > > > > @@ -122,6 +122,21 @@ RTC bindings based on SCU Message
> Protocol
> > > > > Required properties:
> > > > > - compatible: should be "fsl,imx8qxp-sc-rtc";
> > > > >
> > > > > +Thermal bindings based on SCU Message Protocol
> > > > > +------------------------------------------------------------
> > > > > +
> > > > > +Required properties:
> > > > > +- compatible: Should be :
> > > > > + "fsl,imx8qxp-sc-thermal"
> > > > > + followed by "fsl,imx-sc-thermal";
> > > > > +
> > > > > +- #thermal-sensor-cells: See
> > > > Documentation/devicetree/bindings/thermal/thermal.txt
> > > > > + for a description.
> > > > > +
> > > > > +- imx,sensor-resource-id: A single integer for single thermal
> > > > > +zone's
> > > > resource ID or
> > > > > + an array of integers to specify each
> > > > > + thermal
> > > > zone's sensor
> > > > > + resource ID.
> > > >
> > > > Can't you put the resource ids in the thermal-sensor cells? Why do
> > > > you need to list them here?
> > >
> > > For the thermal-sensor cells, if you meant the argument of tsens
> > > phandle, then the reason is that argument is for sensor index
> > > starting from 0, previous I use it for our resource ID, but it looks
> > > confused, since user will think there are many sensors there per
> Eduardo's comment.
> > >
> > > + thermal-sensors = <&tsens 0>;
> > >
> > > If you meant putting it in each thermal sensor node instead of "tsens"
> > > node, then in previous patch series, I put this "
> > > imx,sensor-resource-id " property in each thermal sensor node, but
> > > the thermal sensor nodes are parsed by common thermal framework,
> > > thermal driver will need to find the thermal zone node and go
> > > through every child node to get the resource id again, so Eduardo
> > > suggested to put it in
> > our platform tsens node, that makes our thermal driver code much more
> > simple.
> >
> > The phandle args are meant to be an id typically. There's absolutely
> > no requirement they are 0-N based. They often are because things like
> > interrupts are 0-N or clocks have no h/w id. If you already have an id, use
> > it.
> > Don't invent your own.
>
> At the beginning, I put the HW resource ID in the "tsens" phandle argument
> of "thermal-sensors" node, see below patch I sent before, the benefit is I do
> NOT need to add new property for passing HW resource ID to driver, the
> disadvantage is, I have to parse the thermal_zones' each child node and get
> the HW resource ID from phandle argument(searing thermal_zones node
> and go through all its child node, and get the phandle argument), they are by
> default ONLY parsed by thermal core driver. When we register thermal zone,
> we have to pass the HW resource ID when calling
> devm_thermal_zone_of_sensor_register(), if we add our own property to
> pass the HW resource ID, then no need to do so, we just pass the index 0-N
> for each thermal sensors in devicetree which also with phandle argument 0-
> N. So using our own property makes the driver much more simple.
>
> So, @Eduardo, which direction I should go? Looks like Rob suggests just put
> the HW resource ID in the phandle argument like what I did at the beginning,
> can you advise?
>
> Thanks,
> Anson.
>
> https://patchwork.kernel.org/patch/10703849/
> > + thermal_zones: thermal-zones {
> > + cpu-thermal0 {
> > + polling-delay-passive = <250>;
> > + polling-delay = <2000>;
> > + thermal-sensors = <&tsens 355>;
> > + trips {
> > + cpu_alert0: trip0 {
> > + temperature = <107000>;
> > + hysteresis = <2000>;
> > + type = "passive";
> > + };
>
> >
> > Rob
