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* [PATCH 1/3] PM / OPP: Add "opp-supported-hw" binding
       [not found] <cover.1446167359.git.viresh.kumar@linaro.org>
@ 2015-10-30  1:25 ` Viresh Kumar
  2015-10-30 21:49   ` Stephen Boyd
  2015-10-30 22:18   ` Stephen Boyd
  2015-10-30  1:25 ` [PATCH 2/3] PM / OPP: Add {opp-microvolt|opp-microamp|turbo-mode|opp-suspend}-<name> binding Viresh Kumar
  2015-10-30  1:25 ` [PATCH 3/3] PM / OPP: Remove 'operating-points-names' binding Viresh Kumar
  2 siblings, 2 replies; 18+ messages in thread
From: Viresh Kumar @ 2015-10-30  1:25 UTC (permalink / raw)
  To: Rafael Wysocki, robh+dt, sboyd, lee.jones
  Cc: linaro-kernel, linux-pm, mark.rutland, pawel.moll,
	ijc+devicetree, galak, nm, devicetree, Viresh Kumar, open list,
	Rafael J. Wysocki

We may want to enable only a subset of OPPs, from the bigger list of
OPPs, based on what version of the hardware we are running on. This
would enable us to not duplicate OPP tables for every version of the
hardware we support.

To enable that, this patch defines a new property 'opp-supported-hw'. It
can support any number of hierarchy levels of the versions the hardware
follows. And based on the selected hardware versions, we can pick only
the relevant OPPs at runtime.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 Documentation/devicetree/bindings/opp/opp.txt | 57 +++++++++++++++++++++++++++
 1 file changed, 57 insertions(+)

diff --git a/Documentation/devicetree/bindings/opp/opp.txt b/Documentation/devicetree/bindings/opp/opp.txt
index 0cb44dc21f97..96892057586a 100644
--- a/Documentation/devicetree/bindings/opp/opp.txt
+++ b/Documentation/devicetree/bindings/opp/opp.txt
@@ -123,6 +123,18 @@ properties.
 - opp-suspend: Marks the OPP to be used during device suspend. Only one OPP in
   the table should have this.
 
+- opp-supported-hw: User defined array containing a hierarchy of hardware
+  version numbers, supported by the OPP. For example: a platform with hierarchy
+  of three levels of versions (A, B and C), this field should be like <X Y Z>,
+  where X corresponds to Version hierarchy A, Y corresponds to version hierarchy
+  B and Z corresponds to version hierarchy C.
+
+  Each level of hierarchy is represented by a 32 bit value, and so there can be
+  only 32 different supported version per hierarchy. i.e. 1 bit per version. A
+  value of 0xFFFFFFFF will enable the OPP for all versions for that hierarchy
+  level. And a value of 0x00000000 will disable the OPP completely, and so we
+  never want that to happen.
+
 - status: Marks the node enabled/disabled.
 
 Example 1: Single cluster Dual-core ARM cortex A9, switch DVFS states together.
@@ -463,3 +475,48 @@ Example 5: Multiple OPP tables
 		};
 	};
 };
+
+Example 6: opp-supported-hw
+(example: three level hierarchy of versions: cuts, substrate and process)
+
+/ {
+	cpus {
+		cpu@0 {
+			compatible = "arm,cortex-a7";
+			...
+
+			cpu-supply = <&cpu_supply>
+			operating-points-v2 = <&cpu0_opp_table_slow>;
+		};
+	};
+
+	opp_table {
+		compatible = "operating-points-v2";
+		status = "okay";
+		opp-shared;
+
+		opp00 {
+			/*
+			 * Supports all substrate and process versions for 0xF
+			 * cuts, i.e. only first four cuts.
+			 */
+			opp-supported-hw = <0xF 0xFFFFFFFF 0xFFFFFFFF>
+			opp-hz = /bits/ 64 <600000000>;
+			opp-microvolt = <900000 915000 925000>;
+			...
+		};
+
+		opp01 {
+			/*
+			 * Supports:
+			 * - cuts: only one, 6th cut (represented by 6th bit).
+			 * - substrate: supports 16 different substrate versions
+			 * - process: supports 9 different process versions
+			 */
+			opp-supported-hw = <0x20 0xff0000ff 0x0000f4f0>
+			opp-hz = /bits/ 64 <800000000>;
+			opp-microvolt = <900000 915000 925000>;
+			...
+		};
+	};
+};
-- 
2.6.2.198.g614a2ac


^ permalink raw reply related	[flat|nested] 18+ messages in thread

* [PATCH 2/3] PM / OPP: Add {opp-microvolt|opp-microamp|turbo-mode|opp-suspend}-<name> binding
       [not found] <cover.1446167359.git.viresh.kumar@linaro.org>
  2015-10-30  1:25 ` [PATCH 1/3] PM / OPP: Add "opp-supported-hw" binding Viresh Kumar
@ 2015-10-30  1:25 ` Viresh Kumar
  2015-10-30 21:54   ` Stephen Boyd
  2015-10-30  1:25 ` [PATCH 3/3] PM / OPP: Remove 'operating-points-names' binding Viresh Kumar
  2 siblings, 1 reply; 18+ messages in thread
From: Viresh Kumar @ 2015-10-30  1:25 UTC (permalink / raw)
  To: Rafael Wysocki, robh+dt, sboyd, lee.jones
  Cc: linaro-kernel, linux-pm, mark.rutland, pawel.moll,
	ijc+devicetree, galak, nm, devicetree, Viresh Kumar, open list,
	Rafael J. Wysocki

Depending on the version of hardware or its properties, which are only
known at runtime, various properties of the OPP can change. For example,
an OPP with frequency 1.2 GHz, may have different voltage/current
requirements based on the version of the hardware it is running on.
Similarly, it may or may not be a turbo or suspend OPP on those
circumstances.

In order to not replicate the same OPP tables for varying values of all
such fields, this commit introduces the concept of opp-property-<name>.
The <name> can be chosen by the platform at runtime, and OPPs will be
initialized depending on that name string. Currently support is extended
for the following properties:
- opp-microvolt-<name>
- opp-microamp-<name>
- turbo-mode-<name>
- opp-suspend-<name>

If the name string isn't provided by the platform, or if it is provided
but doesn't match the properties present in the OPP node, we will fall
back to the original properties without the -<name> string, if they are
available.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 Documentation/devicetree/bindings/opp/opp.txt | 58 +++++++++++++++++++++++++++
 1 file changed, 58 insertions(+)

diff --git a/Documentation/devicetree/bindings/opp/opp.txt b/Documentation/devicetree/bindings/opp/opp.txt
index 96892057586a..6e0dd8db3b86 100644
--- a/Documentation/devicetree/bindings/opp/opp.txt
+++ b/Documentation/devicetree/bindings/opp/opp.txt
@@ -100,6 +100,14 @@ properties.
   Entries for multiple regulators must be present in the same order as
   regulators are specified in device's DT node.
 
+- opp-microvolt-<name>: Named opp-microvolt property. This is exactly similar to
+  the above opp-microvolt property, but allows multiple voltage ranges to be
+  provided for the same OPP. At runtime, the platform can pick a <name> and
+  matching opp-microvolt-<name> property will be enabled for all OPPs. If the
+  platform doesn't pick a specific <name> or the <name> doesn't match with any
+  opp-microvolt-<name> properties, then opp-microvolt property shall be used, if
+  present.
+
 - opp-microamp: The maximum current drawn by the device in microamperes
   considering system specific parameters (such as transients, process, aging,
   maximum operating temperature range etc.) as necessary. This may be used to
@@ -112,6 +120,9 @@ properties.
   for few regulators, then this should be marked as zero for them. If it isn't
   required for any regulator, then this property need not be present.
 
+- opp-microamp-<name>: Named opp-microamp property. Similar to
+  opp-microvolt-<name> property, but for microamp instead.
+
 - clock-latency-ns: Specifies the maximum possible transition latency (in
   nanoseconds) for switching to this OPP from any other OPP.
 
@@ -120,9 +131,15 @@ properties.
   frequency for a short duration of time limited by the device's power, current
   and thermal limits.
 
+- turbo-mode-<name>: Named turbo-mode property. Similar to opp-microvolt-<name>
+  property, but for turbo mode instead.
+
 - opp-suspend: Marks the OPP to be used during device suspend. Only one OPP in
   the table should have this.
 
+- opp-suspend-<name>: Named opp-suspend property. Similar to
+  opp-microvolt-<name> property, but for suspend opp instead.
+
 - opp-supported-hw: User defined array containing a hierarchy of hardware
   version numbers, supported by the OPP. For example: a platform with hierarchy
   of three levels of versions (A, B and C), this field should be like <X Y Z>,
@@ -520,3 +537,44 @@ Example 6: opp-supported-hw
 		};
 	};
 };
+
+Example 7: opp-microvolt-<name>, opp-microamp-<name>, turbo-mode-<name>,
+opp-suspend-<name>:
+(example: device with two possible microvolt ranges: slow and fast)
+
+/ {
+	cpus {
+		cpu@0 {
+			compatible = "arm,cortex-a7";
+			...
+
+			operating-points-v2 = <&cpu0_opp_table>;
+		};
+	};
+
+	cpu0_opp_table: opp_table0 {
+		compatible = "operating-points-v2";
+		opp-shared;
+
+		opp00 {
+			opp-hz = /bits/ 64 <1000000000>;
+			opp-microvolt-slow = <900000 915000 925000>;
+			opp-microvolt-fast = <970000 975000 985000>;
+			opp-microamp-slow =  <70000>;
+			opp-microamp-fast =  <71000>;
+			turbo-mode-slow; /* Will be used as turbo only if 'slow' is chosen */
+			opp-suspend-slow; /* Will be used as suspend-opp only if 'slow' is chosen */
+		};
+
+		opp01 {
+			opp-hz = /bits/ 64 <1200000000>;
+			opp-microvolt-slow = <900000 915000 925000>, /* Supply vcc0 */
+					      <910000 925000 935000>; /* Supply vcc1 */
+			opp-microvolt-fast = <970000 975000 985000>, /* Supply vcc0 */
+					     <960000 965000 975000>; /* Supply vcc1 */
+			opp-microamp =  <70000>; /* Will be used for both slow/fast */
+			turbo-mode; /* Always used as turbo */
+			opp-suspend-fast; /* Will be used as suspend opp only if 'fast' is chosen */
+		};
+	};
+};
-- 
2.6.2.198.g614a2ac


^ permalink raw reply related	[flat|nested] 18+ messages in thread

* [PATCH 3/3] PM / OPP: Remove 'operating-points-names' binding
       [not found] <cover.1446167359.git.viresh.kumar@linaro.org>
  2015-10-30  1:25 ` [PATCH 1/3] PM / OPP: Add "opp-supported-hw" binding Viresh Kumar
  2015-10-30  1:25 ` [PATCH 2/3] PM / OPP: Add {opp-microvolt|opp-microamp|turbo-mode|opp-suspend}-<name> binding Viresh Kumar
@ 2015-10-30  1:25 ` Viresh Kumar
  2015-10-30 21:54   ` Stephen Boyd
  2 siblings, 1 reply; 18+ messages in thread
From: Viresh Kumar @ 2015-10-30  1:25 UTC (permalink / raw)
  To: Rafael Wysocki, robh+dt, sboyd, lee.jones
  Cc: linaro-kernel, linux-pm, mark.rutland, pawel.moll,
	ijc+devicetree, galak, nm, devicetree, Viresh Kumar, open list,
	Rafael J. Wysocki

These aren't used until now by any DT files and wouldn't be used now as
we have a better scheme in place now, i.e. opp-property-<name>
properties.

Remove the (useless) binding without breaking ABI.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 Documentation/devicetree/bindings/opp/opp.txt | 62 +--------------------------
 1 file changed, 2 insertions(+), 60 deletions(-)

diff --git a/Documentation/devicetree/bindings/opp/opp.txt b/Documentation/devicetree/bindings/opp/opp.txt
index 6e0dd8db3b86..9d2e08f488b5 100644
--- a/Documentation/devicetree/bindings/opp/opp.txt
+++ b/Documentation/devicetree/bindings/opp/opp.txt
@@ -45,21 +45,10 @@ Devices supporting OPPs must set their "operating-points-v2" property with
 phandle to a OPP table in their DT node. The OPP core will use this phandle to
 find the operating points for the device.
 
-Devices may want to choose OPP tables at runtime and so can provide a list of
-phandles here. But only *one* of them should be chosen at runtime. This must be
-accompanied by a corresponding "operating-points-names" property, to uniquely
-identify the OPP tables.
-
 If required, this can be extended for SoC vendor specfic bindings. Such bindings
 should be documented as Documentation/devicetree/bindings/power/<vendor>-opp.txt
 and should have a compatible description like: "operating-points-v2-<vendor>".
 
-Optional properties:
-- operating-points-names: Names of OPP tables (required if multiple OPP
-  tables are present), to uniquely identify them. The same list must be present
-  for all the CPUs which are sharing clock/voltage rails and hence the OPP
-  tables.
-
 * OPP Table Node
 
 This describes the OPPs belonging to a device. This node can have following
@@ -446,54 +435,7 @@ Example 4: Handling multiple regulators
 	};
 };
 
-Example 5: Multiple OPP tables
-
-/ {
-	cpus {
-		cpu@0 {
-			compatible = "arm,cortex-a7";
-			...
-
-			cpu-supply = <&cpu_supply>
-			operating-points-v2 = <&cpu0_opp_table_slow>, <&cpu0_opp_table_fast>;
-			operating-points-names = "slow", "fast";
-		};
-	};
-
-	cpu0_opp_table_slow: opp_table_slow {
-		compatible = "operating-points-v2";
-		status = "okay";
-		opp-shared;
-
-		opp00 {
-			opp-hz = /bits/ 64 <600000000>;
-			...
-		};
-
-		opp01 {
-			opp-hz = /bits/ 64 <800000000>;
-			...
-		};
-	};
-
-	cpu0_opp_table_fast: opp_table_fast {
-		compatible = "operating-points-v2";
-		status = "okay";
-		opp-shared;
-
-		opp10 {
-			opp-hz = /bits/ 64 <1000000000>;
-			...
-		};
-
-		opp11 {
-			opp-hz = /bits/ 64 <1100000000>;
-			...
-		};
-	};
-};
-
-Example 6: opp-supported-hw
+Example 5: opp-supported-hw
 (example: three level hierarchy of versions: cuts, substrate and process)
 
 / {
@@ -538,7 +480,7 @@ Example 6: opp-supported-hw
 	};
 };
 
-Example 7: opp-microvolt-<name>, opp-microamp-<name>, turbo-mode-<name>,
+Example 6: opp-microvolt-<name>, opp-microamp-<name>, turbo-mode-<name>,
 opp-suspend-<name>:
 (example: device with two possible microvolt ranges: slow and fast)
 
-- 
2.6.2.198.g614a2ac


^ permalink raw reply related	[flat|nested] 18+ messages in thread

* Re: [PATCH 1/3] PM / OPP: Add "opp-supported-hw" binding
  2015-10-30  1:25 ` [PATCH 1/3] PM / OPP: Add "opp-supported-hw" binding Viresh Kumar
@ 2015-10-30 21:49   ` Stephen Boyd
  2015-10-31  2:16     ` Viresh Kumar
  2015-11-02 16:07     ` Viresh Kumar
  2015-10-30 22:18   ` Stephen Boyd
  1 sibling, 2 replies; 18+ messages in thread
From: Stephen Boyd @ 2015-10-30 21:49 UTC (permalink / raw)
  To: Viresh Kumar
  Cc: Rafael Wysocki, robh+dt, lee.jones, linaro-kernel, linux-pm,
	mark.rutland, pawel.moll, ijc+devicetree, galak, nm, devicetree,
	open list, Rafael J. Wysocki

On 10/30, Viresh Kumar wrote:
> +- opp-supported-hw: User defined array containing a hierarchy of hardware
> +  version numbers, supported by the OPP. For example: a platform with hierarchy
> +  of three levels of versions (A, B and C), this field should be like <X Y Z>,
> +  where X corresponds to Version hierarchy A, Y corresponds to version hierarchy
> +  B and Z corresponds to version hierarchy C.
> +
> +  Each level of hierarchy is represented by a 32 bit value, and so there can be
> +  only 32 different supported version per hierarchy. i.e. 1 bit per version. A
> +  value of 0xFFFFFFFF will enable the OPP for all versions for that hierarchy
> +  level. And a value of 0x00000000 will disable the OPP completely, and so we
> +  never want that to happen.

I suppose if you wanted to have 64 possible combinations of some
attribute you would just extend it to two 32 bit numbers in
sequence? I don't see the limitation here, and hopefully there
isn't a limitation so that we can specify sufficiently large
numbers with more bits if we need to.

-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH 2/3] PM / OPP: Add {opp-microvolt|opp-microamp|turbo-mode|opp-suspend}-<name> binding
  2015-10-30  1:25 ` [PATCH 2/3] PM / OPP: Add {opp-microvolt|opp-microamp|turbo-mode|opp-suspend}-<name> binding Viresh Kumar
@ 2015-10-30 21:54   ` Stephen Boyd
  0 siblings, 0 replies; 18+ messages in thread
From: Stephen Boyd @ 2015-10-30 21:54 UTC (permalink / raw)
  To: Viresh Kumar
  Cc: Rafael Wysocki, robh+dt, lee.jones, linaro-kernel, linux-pm,
	mark.rutland, pawel.moll, ijc+devicetree, galak, nm, devicetree,
	open list, Rafael J. Wysocki

On 10/30, Viresh Kumar wrote:
> Depending on the version of hardware or its properties, which are only
> known at runtime, various properties of the OPP can change. For example,
> an OPP with frequency 1.2 GHz, may have different voltage/current
> requirements based on the version of the hardware it is running on.
> Similarly, it may or may not be a turbo or suspend OPP on those
> circumstances.
> 
> In order to not replicate the same OPP tables for varying values of all
> such fields, this commit introduces the concept of opp-property-<name>.
> The <name> can be chosen by the platform at runtime, and OPPs will be
> initialized depending on that name string. Currently support is extended
> for the following properties:
> - opp-microvolt-<name>
> - opp-microamp-<name>
> - turbo-mode-<name>
> - opp-suspend-<name>
> 
> If the name string isn't provided by the platform, or if it is provided
> but doesn't match the properties present in the OPP node, we will fall
> back to the original properties without the -<name> string, if they are
> available.
> 
> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
> ---

Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>

-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH 3/3] PM / OPP: Remove 'operating-points-names' binding
  2015-10-30  1:25 ` [PATCH 3/3] PM / OPP: Remove 'operating-points-names' binding Viresh Kumar
@ 2015-10-30 21:54   ` Stephen Boyd
  0 siblings, 0 replies; 18+ messages in thread
From: Stephen Boyd @ 2015-10-30 21:54 UTC (permalink / raw)
  To: Viresh Kumar
  Cc: Rafael Wysocki, robh+dt, lee.jones, linaro-kernel, linux-pm,
	mark.rutland, pawel.moll, ijc+devicetree, galak, nm, devicetree,
	open list, Rafael J. Wysocki

On 10/30, Viresh Kumar wrote:
> These aren't used until now by any DT files and wouldn't be used now as
> we have a better scheme in place now, i.e. opp-property-<name>
> properties.
> 
> Remove the (useless) binding without breaking ABI.
> 
> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
> ---

Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>

-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH 1/3] PM / OPP: Add "opp-supported-hw" binding
  2015-10-30  1:25 ` [PATCH 1/3] PM / OPP: Add "opp-supported-hw" binding Viresh Kumar
  2015-10-30 21:49   ` Stephen Boyd
@ 2015-10-30 22:18   ` Stephen Boyd
  2015-10-31  2:20     ` Viresh Kumar
  2015-11-03  2:29     ` Viresh Kumar
  1 sibling, 2 replies; 18+ messages in thread
From: Stephen Boyd @ 2015-10-30 22:18 UTC (permalink / raw)
  To: Viresh Kumar
  Cc: Rafael Wysocki, robh+dt, lee.jones, linaro-kernel, linux-pm,
	mark.rutland, pawel.moll, ijc+devicetree, galak, nm, devicetree,
	open list, Rafael J. Wysocki

On 10/30, Viresh Kumar wrote:
> +	opp_table {
> +		compatible = "operating-points-v2";
> +		status = "okay";
> +		opp-shared;
> +
> +		opp00 {

A side-note. I wonder if it would be better style to have the
node name be:

		opp@600000000 {

At least it seems that the assumption is we can store all the
possible combinations of OPP values for a particular frequency in
the same node. Following this style would make dt compilation
fail if two nodes have the same frequency.

Also, this makes it sound like opp-supported-hw is really just
telling us if this is a supported frequency or not for the
particular device we're running on. The current wording makes it
sound like we could have two OPP nodes with the same frequency
but different voltages inside them, which we're trying to
discourage by compressing the tables into less nodes.

I think in Lee's case we're only going to use the cuts parameter
to figure out if the OPP is supported or not. On qcom platforms
we will only use one parameter for this property as well, the
speed bin. The slow/fast and version stuff will be handled by
named opp properties.

> +			/*
> +			 * Supports all substrate and process versions for 0xF
> +			 * cuts, i.e. only first four cuts.
> +			 */
> +			opp-supported-hw = <0xF 0xFFFFFFFF 0xFFFFFFFF>
> +			opp-hz = /bits/ 64 <600000000>;
> +			opp-microvolt = <900000 915000 925000>;

-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH 1/3] PM / OPP: Add "opp-supported-hw" binding
  2015-10-30 21:49   ` Stephen Boyd
@ 2015-10-31  2:16     ` Viresh Kumar
  2015-11-02 19:21       ` Stephen Boyd
  2015-11-02 16:07     ` Viresh Kumar
  1 sibling, 1 reply; 18+ messages in thread
From: Viresh Kumar @ 2015-10-31  2:16 UTC (permalink / raw)
  To: Stephen Boyd
  Cc: Rafael Wysocki, robh+dt, lee.jones, linaro-kernel, linux-pm,
	mark.rutland, pawel.moll, ijc+devicetree, galak, nm, devicetree,
	open list, Rafael J. Wysocki

On 30-10-15, 14:49, Stephen Boyd wrote:
> I suppose if you wanted to have 64 possible combinations of some
> attribute you would just extend it to two 32 bit numbers in
> sequence? I don't see the limitation here, and hopefully there
> isn't a limitation so that we can specify sufficiently large
> numbers with more bits if we need to.

Yeah, we discussed this earlier when Lee had the same query and I
suggested the exact same thing to him then.

-- 
viresh

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH 1/3] PM / OPP: Add "opp-supported-hw" binding
  2015-10-30 22:18   ` Stephen Boyd
@ 2015-10-31  2:20     ` Viresh Kumar
  2015-11-02 15:13       ` Rob Herring
  2015-11-02 19:20       ` Stephen Boyd
  2015-11-03  2:29     ` Viresh Kumar
  1 sibling, 2 replies; 18+ messages in thread
From: Viresh Kumar @ 2015-10-31  2:20 UTC (permalink / raw)
  To: Stephen Boyd
  Cc: Rafael Wysocki, robh+dt, lee.jones, linaro-kernel, linux-pm,
	mark.rutland, pawel.moll, ijc+devicetree, galak, nm, devicetree,
	open list, Rafael J. Wysocki

On 30-10-15, 15:18, Stephen Boyd wrote:
> A side-note. I wonder if it would be better style to have the
> node name be:
> 
> 		opp@600000000 {

I thought the @... had a special meaning and we might end up creating
some device for the node then? Perhaps I am mistaken.

But then, yeah it will make it more readable as you mentioned.

> At least it seems that the assumption is we can store all the
> possible combinations of OPP values for a particular frequency in
> the same node. Following this style would make dt compilation
> fail if two nodes have the same frequency.

Right.

> Also, this makes it sound like opp-supported-hw is really just
> telling us if this is a supported frequency or not for the
> particular device we're running on.

That's right.

> The current wording makes it

Of the commit log ? Or the way the nodes are written?

> sound like we could have two OPP nodes with the same frequency
> but different voltages inside them, which we're trying to
> discourage by compressing the tables into less nodes.

No no, we can't have two nodes with same frequency.

-- 
viresh

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH 1/3] PM / OPP: Add "opp-supported-hw" binding
  2015-10-31  2:20     ` Viresh Kumar
@ 2015-11-02 15:13       ` Rob Herring
  2015-11-02 16:08         ` Viresh Kumar
  2015-11-02 19:20       ` Stephen Boyd
  1 sibling, 1 reply; 18+ messages in thread
From: Rob Herring @ 2015-11-02 15:13 UTC (permalink / raw)
  To: Viresh Kumar
  Cc: Stephen Boyd, Rafael Wysocki, Lee Jones, linaro-kernel, linux-pm,
	Mark Rutland, Pawel Moll, Ian Campbell, Kumar Gala,
	Nishanth Menon, devicetree, open list, Rafael J. Wysocki

On Fri, Oct 30, 2015 at 9:20 PM, Viresh Kumar <viresh.kumar@linaro.org> wrote:
> On 30-10-15, 15:18, Stephen Boyd wrote:
>> A side-note. I wonder if it would be better style to have the
>> node name be:
>>
>>               opp@600000000 {
>
> I thought the @... had a special meaning and we might end up creating
> some device for the node then? Perhaps I am mistaken.

There is no special meaning, just convention which is the unit-address
should match the reg property address. I'm okay with an exception
here.

Rob

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH 1/3] PM / OPP: Add "opp-supported-hw" binding
  2015-10-30 21:49   ` Stephen Boyd
  2015-10-31  2:16     ` Viresh Kumar
@ 2015-11-02 16:07     ` Viresh Kumar
  1 sibling, 0 replies; 18+ messages in thread
From: Viresh Kumar @ 2015-11-02 16:07 UTC (permalink / raw)
  To: Stephen Boyd
  Cc: Rafael Wysocki, robh+dt, lee.jones, linaro-kernel, linux-pm,
	mark.rutland, pawel.moll, ijc+devicetree, galak, nm, devicetree,
	open list, Rafael J. Wysocki

On 30-10-15, 14:49, Stephen Boyd wrote:
> I suppose if you wanted to have 64 possible combinations of some
> attribute you would just extend it to two 32 bit numbers in
> sequence? I don't see the limitation here, and hopefully there
> isn't a limitation so that we can specify sufficiently large
> numbers with more bits if we need to.

I hope you want to mark this patch with your reviewed-by tag?

-- 
viresh

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH 1/3] PM / OPP: Add "opp-supported-hw" binding
  2015-11-02 15:13       ` Rob Herring
@ 2015-11-02 16:08         ` Viresh Kumar
  0 siblings, 0 replies; 18+ messages in thread
From: Viresh Kumar @ 2015-11-02 16:08 UTC (permalink / raw)
  To: Rob Herring
  Cc: Stephen Boyd, Rafael Wysocki, Lee Jones, linaro-kernel, linux-pm,
	Mark Rutland, Pawel Moll, Ian Campbell, Kumar Gala,
	Nishanth Menon, devicetree, open list, Rafael J. Wysocki

On 02-11-15, 09:13, Rob Herring wrote:
> There is no special meaning, just convention which is the unit-address
> should match the reg property address. I'm okay with an exception
> here.

Thanks, I will update this separately.

-- 
viresh

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH 1/3] PM / OPP: Add "opp-supported-hw" binding
  2015-10-31  2:20     ` Viresh Kumar
  2015-11-02 15:13       ` Rob Herring
@ 2015-11-02 19:20       ` Stephen Boyd
  1 sibling, 0 replies; 18+ messages in thread
From: Stephen Boyd @ 2015-11-02 19:20 UTC (permalink / raw)
  To: Viresh Kumar
  Cc: Rafael Wysocki, robh+dt, lee.jones, linaro-kernel, linux-pm,
	mark.rutland, pawel.moll, ijc+devicetree, galak, nm, devicetree,
	open list, Rafael J. Wysocki

On 10/31, Viresh Kumar wrote:
> On 30-10-15, 15:18, Stephen Boyd wrote:
> 
> > Also, this makes it sound like opp-supported-hw is really just
> > telling us if this is a supported frequency or not for the
> > particular device we're running on.
> 
> That's right.
> 
> > The current wording makes it
> 
> Of the commit log ? Or the way the nodes are written?

The way the documentation is written.

-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH 1/3] PM / OPP: Add "opp-supported-hw" binding
  2015-10-31  2:16     ` Viresh Kumar
@ 2015-11-02 19:21       ` Stephen Boyd
  2015-11-03  2:12         ` Viresh Kumar
  0 siblings, 1 reply; 18+ messages in thread
From: Stephen Boyd @ 2015-11-02 19:21 UTC (permalink / raw)
  To: Viresh Kumar
  Cc: Rafael Wysocki, robh+dt, lee.jones, linaro-kernel, linux-pm,
	mark.rutland, pawel.moll, ijc+devicetree, galak, nm, devicetree,
	open list, Rafael J. Wysocki

On 10/31, Viresh Kumar wrote:
> On 30-10-15, 14:49, Stephen Boyd wrote:
> > I suppose if you wanted to have 64 possible combinations of some
> > attribute you would just extend it to two 32 bit numbers in
> > sequence? I don't see the limitation here, and hopefully there
> > isn't a limitation so that we can specify sufficiently large
> > numbers with more bits if we need to.
> 
> Yeah, we discussed this earlier when Lee had the same query and I
> suggested the exact same thing to him then.
> 

Ah I see that after looking at the previous thread. Perhaps we
can add such information into the documentation so that people
aren't misled into thinking they're limited to 32 bits?

-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH 1/3] PM / OPP: Add "opp-supported-hw" binding
  2015-11-02 19:21       ` Stephen Boyd
@ 2015-11-03  2:12         ` Viresh Kumar
  2015-11-04 22:10           ` Stephen Boyd
  0 siblings, 1 reply; 18+ messages in thread
From: Viresh Kumar @ 2015-11-03  2:12 UTC (permalink / raw)
  To: Stephen Boyd
  Cc: Rafael Wysocki, robh+dt, lee.jones, linaro-kernel, linux-pm,
	mark.rutland, pawel.moll, ijc+devicetree, galak, nm, devicetree,
	open list, Rafael J. Wysocki

On 02-11-15, 11:21, Stephen Boyd wrote:
> Ah I see that after looking at the previous thread. Perhaps we
> can add such information into the documentation so that people
> aren't misled into thinking they're limited to 32 bits?

What about these changes:

diff --git a/Documentation/devicetree/bindings/opp/opp.txt b/Documentation/devicetree/bindings/opp/opp.txt
index 96892057586a..b6ca2239838b 100644
--- a/Documentation/devicetree/bindings/opp/opp.txt
+++ b/Documentation/devicetree/bindings/opp/opp.txt
@@ -123,11 +123,15 @@ properties.
 - opp-suspend: Marks the OPP to be used during device suspend. Only one OPP in
   the table should have this.
 
-- opp-supported-hw: User defined array containing a hierarchy of hardware
-  version numbers, supported by the OPP. For example: a platform with hierarchy
-  of three levels of versions (A, B and C), this field should be like <X Y Z>,
-  where X corresponds to Version hierarchy A, Y corresponds to version hierarchy
-  B and Z corresponds to version hierarchy C.
+- opp-supported-hw: This enables us to select only a subset of OPPs from the
+  larger OPP table, based on what version of the hardware we are running on. We
+  still can't have multiple nodes with the same opp-hz value in OPP table.
+
+  Its an user defined array containing a hierarchy of hardware version numbers,
+  supported by the OPP. For example: a platform with hierarchy of three levels
+  of versions (A, B and C), this field should be like <X Y Z>, where X
+  corresponds to Version hierarchy A, Y corresponds to version hierarchy B and Z
+  corresponds to version hierarchy C.
 
   Each level of hierarchy is represented by a 32 bit value, and so there can be
   only 32 different supported version per hierarchy. i.e. 1 bit per version. A
@@ -135,6 +139,10 @@ properties.
   level. And a value of 0x00000000 will disable the OPP completely, and so we
   never want that to happen.
 
+  If 32 values aren't sufficient for a version hierarchy, than that version
+  hierarchy can be contained in multiple 32 bit values. i.e. <X Y Z1 Z2> in the
+  above example, Z1 & Z2 refer to the version hierarchy Z.
+
 - status: Marks the node enabled/disabled.
 


-- 
viresh

^ permalink raw reply related	[flat|nested] 18+ messages in thread

* Re: [PATCH 1/3] PM / OPP: Add "opp-supported-hw" binding
  2015-10-30 22:18   ` Stephen Boyd
  2015-10-31  2:20     ` Viresh Kumar
@ 2015-11-03  2:29     ` Viresh Kumar
  2015-11-04 22:08       ` Stephen Boyd
  1 sibling, 1 reply; 18+ messages in thread
From: Viresh Kumar @ 2015-11-03  2:29 UTC (permalink / raw)
  To: Stephen Boyd
  Cc: Rafael Wysocki, robh+dt, lee.jones, linaro-kernel, linux-pm,
	mark.rutland, pawel.moll, ijc+devicetree, galak, nm, devicetree,
	open list, Rafael J. Wysocki

On 30-10-15, 15:18, Stephen Boyd wrote:
> A side-note. I wonder if it would be better style to have the
> node name be:
> 
> 		opp@600000000 {
> 
> At least it seems that the assumption is we can store all the
> possible combinations of OPP values for a particular frequency in
> the same node. Following this style would make dt compilation
> fail if two nodes have the same frequency.

From: Viresh Kumar <viresh.kumar@linaro.org>
Date: Tue, 3 Nov 2015 07:51:09 +0530
Subject: [PATCH] PM / OPP: Rename OPP nodes as opp@<opp-hz>

It would be better to name OPP nodes as opp@<opp-hz> as that will ensure
that multiple DT nodes don't contain the same frequency. Of course we
expect the writer to name the node with its opp-hz frequency and not any
other frequency.

And that will let the compile error out if multiple nodes are using the
same opp-hz frequency.

Suggested-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 Documentation/devicetree/bindings/opp/opp.txt | 38 +++++++++++++--------------
 1 file changed, 19 insertions(+), 19 deletions(-)

diff --git a/Documentation/devicetree/bindings/opp/opp.txt b/Documentation/devicetree/bindings/opp/opp.txt
index 8d4a4075d634..3af2eca7212a 100644
--- a/Documentation/devicetree/bindings/opp/opp.txt
+++ b/Documentation/devicetree/bindings/opp/opp.txt
@@ -183,20 +183,20 @@ Example 1: Single cluster Dual-core ARM cortex A9, switch DVFS states together.
 		compatible = "operating-points-v2";
 		opp-shared;
 
-		opp00 {
+		opp@1000000000 {
 			opp-hz = /bits/ 64 <1000000000>;
 			opp-microvolt = <970000 975000 985000>;
 			opp-microamp = <70000>;
 			clock-latency-ns = <300000>;
 			opp-suspend;
 		};
-		opp01 {
+		opp@1100000000 {
 			opp-hz = /bits/ 64 <1100000000>;
 			opp-microvolt = <980000 1000000 1010000>;
 			opp-microamp = <80000>;
 			clock-latency-ns = <310000>;
 		};
-		opp02 {
+		opp@1200000000 {
 			opp-hz = /bits/ 64 <1200000000>;
 			opp-microvolt = <1025000>;
 			clock-latency-ns = <290000>;
@@ -262,20 +262,20 @@ independently.
 		 * independently.
 		 */
 
-		opp00 {
+		opp@1000000000 {
 			opp-hz = /bits/ 64 <1000000000>;
 			opp-microvolt = <970000 975000 985000>;
 			opp-microamp = <70000>;
 			clock-latency-ns = <300000>;
 			opp-suspend;
 		};
-		opp01 {
+		opp@1100000000 {
 			opp-hz = /bits/ 64 <1100000000>;
 			opp-microvolt = <980000 1000000 1010000>;
 			opp-microamp = <80000>;
 			clock-latency-ns = <310000>;
 		};
-		opp02 {
+		opp@1200000000 {
 			opp-hz = /bits/ 64 <1200000000>;
 			opp-microvolt = <1025000>;
 			opp-microamp = <90000;
@@ -338,20 +338,20 @@ DVFS state together.
 		compatible = "operating-points-v2";
 		opp-shared;
 
-		opp00 {
+		opp@1000000000 {
 			opp-hz = /bits/ 64 <1000000000>;
 			opp-microvolt = <970000 975000 985000>;
 			opp-microamp = <70000>;
 			clock-latency-ns = <300000>;
 			opp-suspend;
 		};
-		opp01 {
+		opp@1100000000 {
 			opp-hz = /bits/ 64 <1100000000>;
 			opp-microvolt = <980000 1000000 1010000>;
 			opp-microamp = <80000>;
 			clock-latency-ns = <310000>;
 		};
-		opp02 {
+		opp@1200000000 {
 			opp-hz = /bits/ 64 <1200000000>;
 			opp-microvolt = <1025000>;
 			opp-microamp = <90000>;
@@ -364,20 +364,20 @@ DVFS state together.
 		compatible = "operating-points-v2";
 		opp-shared;
 
-		opp10 {
+		opp@1300000000 {
 			opp-hz = /bits/ 64 <1300000000>;
 			opp-microvolt = <1045000 1050000 1055000>;
 			opp-microamp = <95000>;
 			clock-latency-ns = <400000>;
 			opp-suspend;
 		};
-		opp11 {
+		opp@1400000000 {
 			opp-hz = /bits/ 64 <1400000000>;
 			opp-microvolt = <1075000>;
 			opp-microamp = <100000>;
 			clock-latency-ns = <400000>;
 		};
-		opp12 {
+		opp@1500000000 {
 			opp-hz = /bits/ 64 <1500000000>;
 			opp-microvolt = <1010000 1100000 1110000>;
 			opp-microamp = <95000>;
@@ -404,7 +404,7 @@ Example 4: Handling multiple regulators
 		compatible = "operating-points-v2";
 		opp-shared;
 
-		opp00 {
+		opp@1000000000 {
 			opp-hz = /bits/ 64 <1000000000>;
 			opp-microvolt = <970000>, /* Supply 0 */
 					<960000>, /* Supply 1 */
@@ -417,7 +417,7 @@ Example 4: Handling multiple regulators
 
 		/* OR */
 
-		opp00 {
+		opp@1000000000 {
 			opp-hz = /bits/ 64 <1000000000>;
 			opp-microvolt = <970000 975000 985000>, /* Supply 0 */
 					<960000 965000 975000>, /* Supply 1 */
@@ -430,7 +430,7 @@ Example 4: Handling multiple regulators
 
 		/* OR */
 
-		opp00 {
+		opp@1000000000 {
 			opp-hz = /bits/ 64 <1000000000>;
 			opp-microvolt = <970000 975000 985000>, /* Supply 0 */
 					<960000 965000 975000>, /* Supply 1 */
@@ -462,7 +462,7 @@ Example 5: opp-supported-hw
 		status = "okay";
 		opp-shared;
 
-		opp00 {
+		opp@600000000 {
 			/*
 			 * Supports all substrate and process versions for 0xF
 			 * cuts, i.e. only first four cuts.
@@ -473,7 +473,7 @@ Example 5: opp-supported-hw
 			...
 		};
 
-		opp01 {
+		opp@800000000 {
 			/*
 			 * Supports:
 			 * - cuts: only one, 6th cut (represented by 6th bit).
@@ -506,7 +506,7 @@ Example 6: opp-microvolt-<name>, opp-microamp-<name>, turbo-mode-<name>,
 		compatible = "operating-points-v2";
 		opp-shared;
 
-		opp00 {
+		opp@1000000000 {
 			opp-hz = /bits/ 64 <1000000000>;
 			opp-microvolt-slow = <900000 915000 925000>;
 			opp-microvolt-fast = <970000 975000 985000>;
@@ -516,7 +516,7 @@ Example 6: opp-microvolt-<name>, opp-microamp-<name>, turbo-mode-<name>,
 			opp-suspend-slow; /* Will be used as suspend-opp only if 'slow' is chosen */
 		};
 
-		opp01 {
+		opp@1200000000 {
 			opp-hz = /bits/ 64 <1200000000>;
 			opp-microvolt-slow = <900000 915000 925000>, /* Supply vcc0 */
 					      <910000 925000 935000>; /* Supply vcc1 */
-- 
viresh

^ permalink raw reply related	[flat|nested] 18+ messages in thread

* Re: [PATCH 1/3] PM / OPP: Add "opp-supported-hw" binding
  2015-11-03  2:29     ` Viresh Kumar
@ 2015-11-04 22:08       ` Stephen Boyd
  0 siblings, 0 replies; 18+ messages in thread
From: Stephen Boyd @ 2015-11-04 22:08 UTC (permalink / raw)
  To: Viresh Kumar
  Cc: Rafael Wysocki, robh+dt, lee.jones, linaro-kernel, linux-pm,
	mark.rutland, pawel.moll, ijc+devicetree, galak, nm, devicetree,
	open list, Rafael J. Wysocki

On 11/03, Viresh Kumar wrote:
> On 30-10-15, 15:18, Stephen Boyd wrote:
> > A side-note. I wonder if it would be better style to have the
> > node name be:
> > 
> > 		opp@600000000 {
> > 
> > At least it seems that the assumption is we can store all the
> > possible combinations of OPP values for a particular frequency in
> > the same node. Following this style would make dt compilation
> > fail if two nodes have the same frequency.
> 
> From: Viresh Kumar <viresh.kumar@linaro.org>
> Date: Tue, 3 Nov 2015 07:51:09 +0530
> Subject: [PATCH] PM / OPP: Rename OPP nodes as opp@<opp-hz>
> 
> It would be better to name OPP nodes as opp@<opp-hz> as that will ensure
> that multiple DT nodes don't contain the same frequency. Of course we
> expect the writer to name the node with its opp-hz frequency and not any
> other frequency.
> 
> And that will let the compile error out if multiple nodes are using the
> same opp-hz frequency.
> 
> Suggested-by: Stephen Boyd <sboyd@codeaurora.org>
> Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
> ---

Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>

-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project

^ permalink raw reply	[flat|nested] 18+ messages in thread

* Re: [PATCH 1/3] PM / OPP: Add "opp-supported-hw" binding
  2015-11-03  2:12         ` Viresh Kumar
@ 2015-11-04 22:10           ` Stephen Boyd
  0 siblings, 0 replies; 18+ messages in thread
From: Stephen Boyd @ 2015-11-04 22:10 UTC (permalink / raw)
  To: Viresh Kumar
  Cc: Rafael Wysocki, robh+dt, lee.jones, linaro-kernel, linux-pm,
	mark.rutland, pawel.moll, ijc+devicetree, galak, nm, devicetree,
	open list, Rafael J. Wysocki

On 11/03, Viresh Kumar wrote:
> On 02-11-15, 11:21, Stephen Boyd wrote:
> > Ah I see that after looking at the previous thread. Perhaps we
> > can add such information into the documentation so that people
> > aren't misled into thinking they're limited to 32 bits?
> 
> What about these changes:

Yep looks good. Assuming this is squashed into the original:

Reviewed-by: Stephen Boyd <sboyd@codeaurora.org>

One typo below.

> 
> diff --git a/Documentation/devicetree/bindings/opp/opp.txt b/Documentation/devicetree/bindings/opp/opp.txt
> index 96892057586a..b6ca2239838b 100644
> --- a/Documentation/devicetree/bindings/opp/opp.txt
> +++ b/Documentation/devicetree/bindings/opp/opp.txt
> @@ -123,11 +123,15 @@ properties.
>  - opp-suspend: Marks the OPP to be used during device suspend. Only one OPP in
>    the table should have this.
>  
> -- opp-supported-hw: User defined array containing a hierarchy of hardware
> -  version numbers, supported by the OPP. For example: a platform with hierarchy
> -  of three levels of versions (A, B and C), this field should be like <X Y Z>,
> -  where X corresponds to Version hierarchy A, Y corresponds to version hierarchy
> -  B and Z corresponds to version hierarchy C.
> +- opp-supported-hw: This enables us to select only a subset of OPPs from the
> +  larger OPP table, based on what version of the hardware we are running on. We
> +  still can't have multiple nodes with the same opp-hz value in OPP table.
> +
> +  Its an user defined array containing a hierarchy of hardware version numbers,

s/Its/It's/

-- 
Qualcomm Innovation Center, Inc. is a member of Code Aurora Forum,
a Linux Foundation Collaborative Project

^ permalink raw reply	[flat|nested] 18+ messages in thread

end of thread, other threads:[~2015-11-04 22:10 UTC | newest]

Thread overview: 18+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
     [not found] <cover.1446167359.git.viresh.kumar@linaro.org>
2015-10-30  1:25 ` [PATCH 1/3] PM / OPP: Add "opp-supported-hw" binding Viresh Kumar
2015-10-30 21:49   ` Stephen Boyd
2015-10-31  2:16     ` Viresh Kumar
2015-11-02 19:21       ` Stephen Boyd
2015-11-03  2:12         ` Viresh Kumar
2015-11-04 22:10           ` Stephen Boyd
2015-11-02 16:07     ` Viresh Kumar
2015-10-30 22:18   ` Stephen Boyd
2015-10-31  2:20     ` Viresh Kumar
2015-11-02 15:13       ` Rob Herring
2015-11-02 16:08         ` Viresh Kumar
2015-11-02 19:20       ` Stephen Boyd
2015-11-03  2:29     ` Viresh Kumar
2015-11-04 22:08       ` Stephen Boyd
2015-10-30  1:25 ` [PATCH 2/3] PM / OPP: Add {opp-microvolt|opp-microamp|turbo-mode|opp-suspend}-<name> binding Viresh Kumar
2015-10-30 21:54   ` Stephen Boyd
2015-10-30  1:25 ` [PATCH 3/3] PM / OPP: Remove 'operating-points-names' binding Viresh Kumar
2015-10-30 21:54   ` Stephen Boyd

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