| Message ID | 20170331201124.656-1-zajec5@gmail.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | Eduardo Valentin |
| Headers | show |
Rafal, On Fri, Mar 31, 2017 at 10:11:23PM +0200, Rafał Miłecki wrote: > From: Rafał Miłecki <rafal@milecki.pl> > > This commit documents binding for thermal used in Northstar family SoCs. > > Signed-off-by: Rafał Miłecki <rafal@milecki.pl> > --- > V3: Add thermal-zones to the example > Rob: Because of this update, I didn't include Acked-by I got for V2 > --- > .../devicetree/bindings/thermal/brcm,ns-thermal | 26 ++++++++++++++++++++++ > 1 file changed, 26 insertions(+) > create mode 100644 Documentation/devicetree/bindings/thermal/brcm,ns-thermal > > diff --git a/Documentation/devicetree/bindings/thermal/brcm,ns-thermal b/Documentation/devicetree/bindings/thermal/brcm,ns-thermal > new file mode 100644 > index 000000000000..c561c7349f17 > --- /dev/null > +++ b/Documentation/devicetree/bindings/thermal/brcm,ns-thermal > @@ -0,0 +1,26 @@ > +* Broadcom Northstar Thermal > + > +This binding describes thermal sensor that is part of Northstar's DMU (Device > +Management Unit). > + > +Required properties: > +- compatible : Must be "brcm,ns-thermal" > +- reg : iomem address range of PVTMON registers > +- #thermal-sensor-cells : Should be <0> > + > +Example: > + > +thermal: thermal@1800c2c0 { > + compatible = "brcm,ns-thermal"; > + reg = <0x1800c2c0 0x10>; > + #thermal-sensor-cells = <0>; > +}; > + > +thermal-zones { > + cpu_thermal: cpu-thermal { > + polling-delay-passive = <0>; > + polling-delay = <1000>; > + coefficients = <(-556) 418000>; > + thermal-sensors = <&thermal>; You need to define trips and cooling devices here. Otherwise, makes little sense to have this device in thermal subsystem. Here is an example of minimal set: https://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal.git/commit/?h=linus&id=1e2ac9821de6a85d3e8358f238436708d1d46869 The above has no passive action. It is just gonna shutdown the system if temperature crosses a threshold. But, a typical cooling device would be CPU frequency throttling. Do you have that up and running in your routers? > + }; > +}; > -- > 2.11.0 >
On 04/01/2017 09:51 PM, Eduardo Valentin wrote: > On Fri, Mar 31, 2017 at 10:11:23PM +0200, Rafał Miłecki wrote: >> From: Rafał Miłecki <rafal@milecki.pl> >> >> This commit documents binding for thermal used in Northstar family SoCs. >> >> Signed-off-by: Rafał Miłecki <rafal@milecki.pl> >> --- >> V3: Add thermal-zones to the example >> Rob: Because of this update, I didn't include Acked-by I got for V2 >> --- >> .../devicetree/bindings/thermal/brcm,ns-thermal | 26 ++++++++++++++++++++++ >> 1 file changed, 26 insertions(+) >> create mode 100644 Documentation/devicetree/bindings/thermal/brcm,ns-thermal >> >> diff --git a/Documentation/devicetree/bindings/thermal/brcm,ns-thermal b/Documentation/devicetree/bindings/thermal/brcm,ns-thermal >> new file mode 100644 >> index 000000000000..c561c7349f17 >> --- /dev/null >> +++ b/Documentation/devicetree/bindings/thermal/brcm,ns-thermal >> @@ -0,0 +1,26 @@ >> +* Broadcom Northstar Thermal >> + >> +This binding describes thermal sensor that is part of Northstar's DMU (Device >> +Management Unit). >> + >> +Required properties: >> +- compatible : Must be "brcm,ns-thermal" >> +- reg : iomem address range of PVTMON registers >> +- #thermal-sensor-cells : Should be <0> >> + >> +Example: >> + >> +thermal: thermal@1800c2c0 { >> + compatible = "brcm,ns-thermal"; >> + reg = <0x1800c2c0 0x10>; >> + #thermal-sensor-cells = <0>; >> +}; >> + >> +thermal-zones { >> + cpu_thermal: cpu-thermal { >> + polling-delay-passive = <0>; >> + polling-delay = <1000>; >> + coefficients = <(-556) 418000>; >> + thermal-sensors = <&thermal>; > > You need to define trips and cooling devices here. Otherwise, makes > little sense to have this device in thermal subsystem. Here is an > example of minimal set: > https://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal.git/commit/?h=linus&id=1e2ac9821de6a85d3e8358f238436708d1d46869 > > The above has no passive action. It is just gonna shutdown the system if > temperature crosses a threshold. > > But, a typical cooling device would be CPU frequency throttling. Do you have > that up and running in your routers? I don't have CPU freq throttling, so shutdown will be the only solution for critical temp right now. I know I should have at least a trip for critical temperature, but the problem is I don't know what value to use. There isn't any info about this in public datasheets. Broadcom's SDK doesn't mention it. Vendors share only the max environment temp, not the max CPU temp. So for now I only meant to provide user space access to reading current CPU temperature. I could do some stress tests and ask other users to do it as well. Or maybe I could just put in Documentation some round value that makes more or less sense and then work on a proper content of real DTS files? Unless we can get some hint from Broadcom people. Jon? Florian? Anyone?
Hey, On Sat, Apr 01, 2017 at 11:50:26PM +0200, Rafał Miłecki wrote: > On 04/01/2017 09:51 PM, Eduardo Valentin wrote: > >On Fri, Mar 31, 2017 at 10:11:23PM +0200, Rafał Miłecki wrote: > >>From: Rafał Miłecki <rafal@milecki.pl> > >> > >>This commit documents binding for thermal used in Northstar family SoCs. > >> > >>Signed-off-by: Rafał Miłecki <rafal@milecki.pl> > >>--- > >>V3: Add thermal-zones to the example > >> Rob: Because of this update, I didn't include Acked-by I got for V2 > >>--- > >> .../devicetree/bindings/thermal/brcm,ns-thermal | 26 ++++++++++++++++++++++ > >> 1 file changed, 26 insertions(+) > >> create mode 100644 Documentation/devicetree/bindings/thermal/brcm,ns-thermal > >> > >>diff --git a/Documentation/devicetree/bindings/thermal/brcm,ns-thermal b/Documentation/devicetree/bindings/thermal/brcm,ns-thermal > >>new file mode 100644 > >>index 000000000000..c561c7349f17 > >>--- /dev/null > >>+++ b/Documentation/devicetree/bindings/thermal/brcm,ns-thermal > >>@@ -0,0 +1,26 @@ > >>+* Broadcom Northstar Thermal > >>+ > >>+This binding describes thermal sensor that is part of Northstar's DMU (Device > >>+Management Unit). > >>+ > >>+Required properties: > >>+- compatible : Must be "brcm,ns-thermal" > >>+- reg : iomem address range of PVTMON registers > >>+- #thermal-sensor-cells : Should be <0> > >>+ > >>+Example: > >>+ > >>+thermal: thermal@1800c2c0 { > >>+ compatible = "brcm,ns-thermal"; > >>+ reg = <0x1800c2c0 0x10>; > >>+ #thermal-sensor-cells = <0>; > >>+}; > >>+ > >>+thermal-zones { > >>+ cpu_thermal: cpu-thermal { > >>+ polling-delay-passive = <0>; > >>+ polling-delay = <1000>; > >>+ coefficients = <(-556) 418000>; > >>+ thermal-sensors = <&thermal>; > > > >You need to define trips and cooling devices here. Otherwise, makes > >little sense to have this device in thermal subsystem. Here is an > >example of minimal set: > >https://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal.git/commit/?h=linus&id=1e2ac9821de6a85d3e8358f238436708d1d46869 > > > >The above has no passive action. It is just gonna shutdown the system if > >temperature crosses a threshold. > > > >But, a typical cooling device would be CPU frequency throttling. Do you have > >that up and running in your routers? > > I don't have CPU freq throttling, so shutdown will be the only solution for > critical temp right now. OK. Is there any plans to get cpu cooling / DVFS working on your boards? > > I know I should have at least a trip for critical temperature, but the problem > is I don't know what value to use. There isn't any info about this in public And that is enough justification to block this to go upstream. We need the correct shutdown threshold value to put as example. If we don't, users of this drivers will be pretty much guessing. > datasheets. Broadcom's SDK doesn't mention it. Vendors share only the max > environment temp, not the max CPU temp. Silicon goes bad typically at 125C. But that also typically requires a good extrapolation of hotspot(s). Some drivers prefer to play safer and use lower numbers (100C). > > So for now I only meant to provide user space access to reading current CPU > temperature. I could do some stress tests and ask other users to do it as well. > I see.. > Or maybe I could just put in Documentation some round value that makes more or > less sense and then work on a proper content of real DTS files? > The problem with the above is that I see very commonly examples being copied into DTS. So, better to have a good binding example/documentation. That is what they are for anyway. > Unless we can get some hint from Broadcom people. Jon? Florian? Anyone? > Yeah, that would be probably best.
On Sat, Apr 1, 2017 at 5:50 PM, Rafał Miłecki <zajec5@gmail.com> wrote: > On 04/01/2017 09:51 PM, Eduardo Valentin wrote: >> >> On Fri, Mar 31, 2017 at 10:11:23PM +0200, Rafał Miłecki wrote: >>> >>> From: Rafał Miłecki <rafal@milecki.pl> >>> >>> This commit documents binding for thermal used in Northstar family SoCs. >>> >>> Signed-off-by: Rafał Miłecki <rafal@milecki.pl> >>> --- >>> V3: Add thermal-zones to the example >>> Rob: Because of this update, I didn't include Acked-by I got for V2 >>> --- >>> .../devicetree/bindings/thermal/brcm,ns-thermal | 26 >>> ++++++++++++++++++++++ >>> 1 file changed, 26 insertions(+) >>> create mode 100644 >>> Documentation/devicetree/bindings/thermal/brcm,ns-thermal >>> >>> diff --git a/Documentation/devicetree/bindings/thermal/brcm,ns-thermal >>> b/Documentation/devicetree/bindings/thermal/brcm,ns-thermal >>> new file mode 100644 >>> index 000000000000..c561c7349f17 >>> --- /dev/null >>> +++ b/Documentation/devicetree/bindings/thermal/brcm,ns-thermal >>> @@ -0,0 +1,26 @@ >>> +* Broadcom Northstar Thermal >>> + >>> +This binding describes thermal sensor that is part of Northstar's DMU >>> (Device >>> +Management Unit). >>> + >>> +Required properties: >>> +- compatible : Must be "brcm,ns-thermal" >>> +- reg : iomem address range of PVTMON registers >>> +- #thermal-sensor-cells : Should be <0> >>> + >>> +Example: >>> + >>> +thermal: thermal@1800c2c0 { >>> + compatible = "brcm,ns-thermal"; >>> + reg = <0x1800c2c0 0x10>; >>> + #thermal-sensor-cells = <0>; >>> +}; >>> + >>> +thermal-zones { >>> + cpu_thermal: cpu-thermal { >>> + polling-delay-passive = <0>; >>> + polling-delay = <1000>; >>> + coefficients = <(-556) 418000>; >>> + thermal-sensors = <&thermal>; >> >> >> You need to define trips and cooling devices here. Otherwise, makes >> little sense to have this device in thermal subsystem. Here is an >> example of minimal set: >> >> https://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal.git/commit/?h=linus&id=1e2ac9821de6a85d3e8358f238436708d1d46869 >> >> The above has no passive action. It is just gonna shutdown the system if >> temperature crosses a threshold. >> >> But, a typical cooling device would be CPU frequency throttling. Do you >> have >> that up and running in your routers? > > > I don't have CPU freq throttling, so shutdown will be the only solution for > critical temp right now. > > I know I should have at least a trip for critical temperature, but the > problem > is I don't know what value to use. There isn't any info about this in public > datasheets. Broadcom's SDK doesn't mention it. Vendors share only the max > environment temp, not the max CPU temp. > > So for now I only meant to provide user space access to reading current CPU > temperature. I could do some stress tests and ask other users to do it as > well. > > Or maybe I could just put in Documentation some round value that makes more > or > less sense and then work on a proper content of real DTS files? > > Unless we can get some hint from Broadcom people. Jon? Florian? Anyone? I'll poke around and see if I can find a datasheet for NS/NSP. Worst case, I can ask one of the HW engineers for NSP, and we can use the same value for NS.
On Sun, Apr 2, 2017 at 11:07 PM, Jon Mason <jon.mason@broadcom.com> wrote: > On Sat, Apr 1, 2017 at 5:50 PM, Rafał Miłecki <zajec5@gmail.com> wrote: >> On 04/01/2017 09:51 PM, Eduardo Valentin wrote: >>> >>> On Fri, Mar 31, 2017 at 10:11:23PM +0200, Rafał Miłecki wrote: >>>> >>>> From: Rafał Miłecki <rafal@milecki.pl> >>>> >>>> This commit documents binding for thermal used in Northstar family SoCs. >>>> >>>> Signed-off-by: Rafał Miłecki <rafal@milecki.pl> >>>> --- >>>> V3: Add thermal-zones to the example >>>> Rob: Because of this update, I didn't include Acked-by I got for V2 >>>> --- >>>> .../devicetree/bindings/thermal/brcm,ns-thermal | 26 >>>> ++++++++++++++++++++++ >>>> 1 file changed, 26 insertions(+) >>>> create mode 100644 >>>> Documentation/devicetree/bindings/thermal/brcm,ns-thermal >>>> >>>> diff --git a/Documentation/devicetree/bindings/thermal/brcm,ns-thermal >>>> b/Documentation/devicetree/bindings/thermal/brcm,ns-thermal >>>> new file mode 100644 >>>> index 000000000000..c561c7349f17 >>>> --- /dev/null >>>> +++ b/Documentation/devicetree/bindings/thermal/brcm,ns-thermal >>>> @@ -0,0 +1,26 @@ >>>> +* Broadcom Northstar Thermal >>>> + >>>> +This binding describes thermal sensor that is part of Northstar's DMU >>>> (Device >>>> +Management Unit). >>>> + >>>> +Required properties: >>>> +- compatible : Must be "brcm,ns-thermal" >>>> +- reg : iomem address range of PVTMON registers >>>> +- #thermal-sensor-cells : Should be <0> >>>> + >>>> +Example: >>>> + >>>> +thermal: thermal@1800c2c0 { >>>> + compatible = "brcm,ns-thermal"; >>>> + reg = <0x1800c2c0 0x10>; >>>> + #thermal-sensor-cells = <0>; >>>> +}; >>>> + >>>> +thermal-zones { >>>> + cpu_thermal: cpu-thermal { >>>> + polling-delay-passive = <0>; >>>> + polling-delay = <1000>; >>>> + coefficients = <(-556) 418000>; >>>> + thermal-sensors = <&thermal>; >>> >>> >>> You need to define trips and cooling devices here. Otherwise, makes >>> little sense to have this device in thermal subsystem. Here is an >>> example of minimal set: >>> >>> https://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal.git/commit/?h=linus&id=1e2ac9821de6a85d3e8358f238436708d1d46869 >>> >>> The above has no passive action. It is just gonna shutdown the system if >>> temperature crosses a threshold. >>> >>> But, a typical cooling device would be CPU frequency throttling. Do you >>> have >>> that up and running in your routers? >> >> >> I don't have CPU freq throttling, so shutdown will be the only solution for >> critical temp right now. >> >> I know I should have at least a trip for critical temperature, but the >> problem >> is I don't know what value to use. There isn't any info about this in public >> datasheets. Broadcom's SDK doesn't mention it. Vendors share only the max >> environment temp, not the max CPU temp. >> >> So for now I only meant to provide user space access to reading current CPU >> temperature. I could do some stress tests and ask other users to do it as >> well. >> >> Or maybe I could just put in Documentation some round value that makes more >> or >> less sense and then work on a proper content of real DTS files? >> >> Unless we can get some hint from Broadcom people. Jon? Florian? Anyone? > > I'll poke around and see if I can find a datasheet for NS/NSP. Worst > case, I can ask one of the HW engineers for NSP, and we can use the > same value for NS. In the NS documentation, under "Absolute Maximum Ratings": The "Maximum Junction Temperature" is 125 C The "Commercial Ambient Temperature (Operating)" range is 0 to 75 C The "Industrial Ambient Temperature (Operating)" range is -40 to 85 C The "Storage Temperature" range is -40 to 125 C In the NSP documentation, under "Absolute Maximum Ratings": The "Maximum Junction Temperature" is 110 C The "Commercial Ambient Temperature (Operating)" range is 0 to 75 C The "Industrial Ambient Temperature (Operating)" range is -40 to 85 C The "Storage Temperature" range is -40 to 125 C I believe the first one is the number you are looking for. Thanks, Jon
On 04/03/2017 04:54 PM, Jon Mason wrote: > On Sun, Apr 2, 2017 at 11:07 PM, Jon Mason <jon.mason@broadcom.com> wrote: >> On Sat, Apr 1, 2017 at 5:50 PM, Rafał Miłecki <zajec5@gmail.com> wrote: >>> On 04/01/2017 09:51 PM, Eduardo Valentin wrote: >>>> >>>> On Fri, Mar 31, 2017 at 10:11:23PM +0200, Rafał Miłecki wrote: >>>>> >>>>> From: Rafał Miłecki <rafal@milecki.pl> >>>>> >>>>> This commit documents binding for thermal used in Northstar family SoCs. >>>>> >>>>> Signed-off-by: Rafał Miłecki <rafal@milecki.pl> >>>>> --- >>>>> V3: Add thermal-zones to the example >>>>> Rob: Because of this update, I didn't include Acked-by I got for V2 >>>>> --- >>>>> .../devicetree/bindings/thermal/brcm,ns-thermal | 26 >>>>> ++++++++++++++++++++++ >>>>> 1 file changed, 26 insertions(+) >>>>> create mode 100644 >>>>> Documentation/devicetree/bindings/thermal/brcm,ns-thermal >>>>> >>>>> diff --git a/Documentation/devicetree/bindings/thermal/brcm,ns-thermal >>>>> b/Documentation/devicetree/bindings/thermal/brcm,ns-thermal >>>>> new file mode 100644 >>>>> index 000000000000..c561c7349f17 >>>>> --- /dev/null >>>>> +++ b/Documentation/devicetree/bindings/thermal/brcm,ns-thermal >>>>> @@ -0,0 +1,26 @@ >>>>> +* Broadcom Northstar Thermal >>>>> + >>>>> +This binding describes thermal sensor that is part of Northstar's DMU >>>>> (Device >>>>> +Management Unit). >>>>> + >>>>> +Required properties: >>>>> +- compatible : Must be "brcm,ns-thermal" >>>>> +- reg : iomem address range of PVTMON registers >>>>> +- #thermal-sensor-cells : Should be <0> >>>>> + >>>>> +Example: >>>>> + >>>>> +thermal: thermal@1800c2c0 { >>>>> + compatible = "brcm,ns-thermal"; >>>>> + reg = <0x1800c2c0 0x10>; >>>>> + #thermal-sensor-cells = <0>; >>>>> +}; >>>>> + >>>>> +thermal-zones { >>>>> + cpu_thermal: cpu-thermal { >>>>> + polling-delay-passive = <0>; >>>>> + polling-delay = <1000>; >>>>> + coefficients = <(-556) 418000>; >>>>> + thermal-sensors = <&thermal>; >>>> >>>> >>>> You need to define trips and cooling devices here. Otherwise, makes >>>> little sense to have this device in thermal subsystem. Here is an >>>> example of minimal set: >>>> >>>> https://git.kernel.org/pub/scm/linux/kernel/git/evalenti/linux-soc-thermal.git/commit/?h=linus&id=1e2ac9821de6a85d3e8358f238436708d1d46869 >>>> >>>> The above has no passive action. It is just gonna shutdown the system if >>>> temperature crosses a threshold. >>>> >>>> But, a typical cooling device would be CPU frequency throttling. Do you >>>> have >>>> that up and running in your routers? >>> >>> >>> I don't have CPU freq throttling, so shutdown will be the only solution for >>> critical temp right now. >>> >>> I know I should have at least a trip for critical temperature, but the >>> problem >>> is I don't know what value to use. There isn't any info about this in public >>> datasheets. Broadcom's SDK doesn't mention it. Vendors share only the max >>> environment temp, not the max CPU temp. >>> >>> So for now I only meant to provide user space access to reading current CPU >>> temperature. I could do some stress tests and ask other users to do it as >>> well. >>> >>> Or maybe I could just put in Documentation some round value that makes more >>> or >>> less sense and then work on a proper content of real DTS files? >>> >>> Unless we can get some hint from Broadcom people. Jon? Florian? Anyone? >> >> I'll poke around and see if I can find a datasheet for NS/NSP. Worst >> case, I can ask one of the HW engineers for NSP, and we can use the >> same value for NS. > > In the NS documentation, under "Absolute Maximum Ratings": > > The "Maximum Junction Temperature" is 125 C > The "Commercial Ambient Temperature (Operating)" range is 0 to 75 C > The "Industrial Ambient Temperature (Operating)" range is -40 to 85 C > The "Storage Temperature" range is -40 to 125 C > > In the NSP documentation, under "Absolute Maximum Ratings": > > The "Maximum Junction Temperature" is 110 C > The "Commercial Ambient Temperature (Operating)" range is 0 to 75 C > The "Industrial Ambient Temperature (Operating)" range is -40 to 85 C > The "Storage Temperature" range is -40 to 125 C > > I believe the first one is the number you are looking for. Thanks a lot for this valuable info! I'll send next version today.
diff --git a/Documentation/devicetree/bindings/thermal/brcm,ns-thermal b/Documentation/devicetree/bindings/thermal/brcm,ns-thermal new file mode 100644 index 000000000000..c561c7349f17 --- /dev/null +++ b/Documentation/devicetree/bindings/thermal/brcm,ns-thermal @@ -0,0 +1,26 @@ +* Broadcom Northstar Thermal + +This binding describes thermal sensor that is part of Northstar's DMU (Device +Management Unit). + +Required properties: +- compatible : Must be "brcm,ns-thermal" +- reg : iomem address range of PVTMON registers +- #thermal-sensor-cells : Should be <0> + +Example: + +thermal: thermal@1800c2c0 { + compatible = "brcm,ns-thermal"; + reg = <0x1800c2c0 0x10>; + #thermal-sensor-cells = <0>; +}; + +thermal-zones { + cpu_thermal: cpu-thermal { + polling-delay-passive = <0>; + polling-delay = <1000>; + coefficients = <(-556) 418000>; + thermal-sensors = <&thermal>; + }; +};