It was never compulsory to have a compatible string in the OPP table. Fix the documentation to mark it optional.
Also update its description a bit.
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- Documentation/devicetree/bindings/opp/opp.txt | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/Documentation/devicetree/bindings/opp/opp.txt b/Documentation/devicetree/bindings/opp/opp.txt index ee91cbdd95ee..5eab6f0215d1 100644 --- a/Documentation/devicetree/bindings/opp/opp.txt +++ b/Documentation/devicetree/bindings/opp/opp.txt @@ -55,14 +55,14 @@ This describes the OPPs belonging to a device. This node can have following properties:
Required properties: -- compatible: Allow OPPs to express their compatibility. It should be: - "operating-points-v2". - - OPP nodes: One or more OPP nodes describing voltage-current-frequency combinations. Their name isn't significant but their phandle can be used to reference an OPP.
Optional properties: +- compatible: Allow OPPs to express their compatibility. It should be + "operating-points-v2" or a vendor specific string. + - opp-shared: Indicates that device nodes using this OPP Table Node's phandle switch their DVFS state together, i.e. they share clock/voltage/current lines. Missing property means devices have independent clock/voltage/current lines,
Multiple regulators per device aren't supported yet by the kernel code and the bindings provided in documentation aren't sufficient to handle that case (as there is no way for kernel code to link multiple voltage/current values to a power supply).
Remove them. These can be added later if required with appropriate changes.
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- Documentation/devicetree/bindings/opp/opp.txt | 68 ++------------------------- 1 file changed, 4 insertions(+), 64 deletions(-)
diff --git a/Documentation/devicetree/bindings/opp/opp.txt b/Documentation/devicetree/bindings/opp/opp.txt index 5eab6f0215d1..5d0595f0a10c 100644 --- a/Documentation/devicetree/bindings/opp/opp.txt +++ b/Documentation/devicetree/bindings/opp/opp.txt @@ -86,8 +86,7 @@ properties. Single entry is for target voltage and three entries are for <target min max> voltages.
- Entries for multiple regulators must be present in the same order as - regulators are specified in device's DT node. + Entries for multiple regulators aren't supported.
- opp-microvolt-<name>: Named opp-microvolt property. This is exactly similar to the above opp-microvolt property, but allows multiple voltage ranges to be @@ -104,10 +103,7 @@ properties.
Should only be set if opp-microvolt is set for the OPP.
- Entries for multiple regulators must be present in the same order as - regulators are specified in device's DT node. If this property isn't required - 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. + Entries for multiple regulators aren't supported.
- opp-microamp-<name>: Named opp-microamp property. Similar to opp-microvolt-<name> property, but for microamp instead. @@ -381,63 +377,7 @@ DVFS state together. }; };
-Example 4: Handling multiple regulators - -/ { - cpus { - cpu@0 { - compatible = "arm,cortex-a7"; - ... - - cpu-supply = <&cpu_supply0>, <&cpu_supply1>, <&cpu_supply2>; - operating-points-v2 = <&cpu0_opp_table>; - }; - }; - - cpu0_opp_table: opp_table0 { - compatible = "operating-points-v2"; - opp-shared; - - opp@1000000000 { - opp-hz = /bits/ 64 <1000000000>; - opp-microvolt = <970000>, /* Supply 0 */ - <960000>, /* Supply 1 */ - <960000>; /* Supply 2 */ - opp-microamp = <70000>, /* Supply 0 */ - <70000>, /* Supply 1 */ - <70000>; /* Supply 2 */ - clock-latency-ns = <300000>; - }; - - /* OR */ - - opp@1000000000 { - opp-hz = /bits/ 64 <1000000000>; - opp-microvolt = <970000 975000 985000>, /* Supply 0 */ - <960000 965000 975000>, /* Supply 1 */ - <960000 965000 975000>; /* Supply 2 */ - opp-microamp = <70000>, /* Supply 0 */ - <70000>, /* Supply 1 */ - <70000>; /* Supply 2 */ - clock-latency-ns = <300000>; - }; - - /* OR */ - - opp@1000000000 { - opp-hz = /bits/ 64 <1000000000>; - opp-microvolt = <970000 975000 985000>, /* Supply 0 */ - <960000 965000 975000>, /* Supply 1 */ - <960000 965000 975000>; /* Supply 2 */ - opp-microamp = <70000>, /* Supply 0 */ - <0>, /* Supply 1 doesn't need this */ - <70000>; /* Supply 2 */ - clock-latency-ns = <300000>; - }; - }; -}; - -Example 5: opp-supported-hw +Example 4: opp-supported-hw (example: three level hierarchy of versions: cuts, substrate and process)
/ { @@ -482,7 +422,7 @@ Example 5: opp-supported-hw }; };
-Example 6: opp-microvolt-<name>, opp-microamp-<name>: +Example 5: opp-microvolt-<name>, opp-microamp-<name>: (example: device with two possible microvolt ranges: slow and fast)
/ {
On Wed, Sep 21, 2016 at 03:02:50PM +0530, Viresh Kumar wrote:
Multiple regulators per device aren't supported yet by the kernel code and the bindings provided in documentation aren't sufficient to handle that case (as there is no way for kernel code to link multiple voltage/current values to a power supply).
What do you mean? Because the supplies are in the cpu node?
Rob
On 23-09-16, 14:59, Rob Herring wrote:
On Wed, Sep 21, 2016 at 03:02:50PM +0530, Viresh Kumar wrote:
Multiple regulators per device aren't supported yet by the kernel code and the bindings provided in documentation aren't sufficient to handle that case (as there is no way for kernel code to link multiple voltage/current values to a power supply).
What do you mean? Because the supplies are in the cpu node?
Not just that. For example if two supplies are present in CPU node like: ABC-supply and XYZ-supply. And the values present in OPP node are like:
opp00 { opp-hz = /bits/ 64 <1700000000>; /* ABC supply XYZ supply */ opp-microvolt = <1300000 1300000 1300000>, <1400000 1400000 1400000>; opp-microamp = <70000>; clock-latency-ns = <30>; opp-suspend; };
Then the code can get regulators with those names (ABC and XYZ), but it can't figure out which triplet in the "opp-microvolt" property belongs to which supply.
I am working on some solution to that, but wanted to keep the entire series self sufficient and so removing the leftovers first in this patch.
On 09/21/2016 02:32 AM, Viresh Kumar wrote:
It was never compulsory to have a compatible string in the OPP table. Fix the documentation to mark it optional.
Also update its description a bit.
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org
Why? I'd prefer the compatible string to be required so we know what sort of node it is.
On 22-09-16, 12:24, Stephen Boyd wrote:
On 09/21/2016 02:32 AM, Viresh Kumar wrote:
It was never compulsory to have a compatible string in the OPP table. Fix the documentation to mark it optional.
Also update its description a bit.
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org
Why? I'd prefer the compatible string to be required so we know what sort of node it is.
Okay, the code doesn't have any checks for it then and that needs to be fixed.
Just for my clarity, for platforms with special OPP bindings and so a different compatible string like: "operating-points-v2-XYZ", should the compatible string contain both "operating-points-v2" and the above one? It would be easier to check for "operating-points-v2" in that case from core code.
On Fri, Sep 23, 2016 at 10:45:26AM +0530, Viresh Kumar wrote:
On 22-09-16, 12:24, Stephen Boyd wrote:
On 09/21/2016 02:32 AM, Viresh Kumar wrote:
It was never compulsory to have a compatible string in the OPP table. Fix the documentation to mark it optional.
NAK.
Also update its description a bit.
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org
Why? I'd prefer the compatible string to be required so we know what sort of node it is.
Agreed.
Okay, the code doesn't have any checks for it then and that needs to be fixed.
Why? The kernel is not a DT validator.
Just for my clarity, for platforms with special OPP bindings and so a different compatible string like: "operating-points-v2-XYZ", should the compatible string contain both "operating-points-v2" and the above one? It would be easier to check for "operating-points-v2" in that case from core code.
That would imply operating-points-v2-XYZ has extra properties or is different in some way. If an OS only understanding operating-points-v2 will work, then yes it should have both. If not, then no.
Rob
On 23-09-16, 14:55, Rob Herring wrote:
On Fri, Sep 23, 2016 at 10:45:26AM +0530, Viresh Kumar wrote:
On 22-09-16, 12:24, Stephen Boyd wrote:
On 09/21/2016 02:32 AM, Viresh Kumar wrote:
It was never compulsory to have a compatible string in the OPP table. Fix the documentation to mark it optional.
NAK.
Also update its description a bit.
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org
Why? I'd prefer the compatible string to be required so we know what sort of node it is.
Agreed.
Okay, the code doesn't have any checks for it then and that needs to be fixed.
Why? The kernel is not a DT validator.
Hmm.. I thought it should be checking if it can parse those bindings or not. What if someone adds compatible property as "foo" for OPP node? Should the OPP code even try to parse it?
Just for my clarity, for platforms with special OPP bindings and so a different compatible string like: "operating-points-v2-XYZ", should the compatible string contain both "operating-points-v2" and the above one? It would be easier to check for "operating-points-v2" in that case from core code.
That would imply operating-points-v2-XYZ has extra properties or is different in some way. If an OS only understanding operating-points-v2 will work, then yes it should have both. If not, then no.
Well, in this case that can't be done fully, so we should have only the -xyz one. Got it, thanks.
The OPP core code doesn't check for the compatible string today and any faulty binding will go unnoticed.
Add a check in OPP core to take care of that.
Signed-off-by: Viresh Kumar viresh.kumar@linaro.org --- This patch replaces: "[PATCH 1/2] PM / OPP: compatible is an optional property".
FWIW, I have checked that none of the current users of operating-points-v2 had this problem and this patch can be merged safely.
drivers/base/power/opp/of.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/drivers/base/power/opp/of.c b/drivers/base/power/opp/of.c index 1dfd3dd92624..111a5cad9f8a 100644 --- a/drivers/base/power/opp/of.c +++ b/drivers/base/power/opp/of.c @@ -318,6 +318,11 @@ static int _of_add_opp_table_v2(struct device *dev, struct device_node *opp_np) struct opp_table *opp_table; int ret = 0, count = 0;
+ if (!of_device_is_compatible(opp_np, "operating-points-v2")) { + dev_err(dev, "Not compatible with operating-points-v2\n"); + return -EINVAL; + } + mutex_lock(&opp_table_lock);
opp_table = _managed_opp(opp_np);
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