On Tue, Dec 26, 2017 at 10:45 PM, Viresh Kumar [off-list ref] wrote:

On 26-12-17, 14:23, Rob Herring wrote:

quoted

quoted

        cpu_opp_table: cpu_opp_table {
                compatible = "operating-points-v2";
                opp-shared;

                opp00 {
                        opp-hz = /bits/ 64 <208000000>;
                        clock-latency-ns = <500000>;
                        power-domain-opp = <&domain_opp_1>;

What is this? opp00 here is not a device. One OPP should not point to
another. "power-domain-opp" is only supposed to appear in devices
alongside power-domains properties.

There are two type of devices:

A.) With fixed performance state requirements and they will have the
new "required-opp" property in the device node itself as you said.

B.) Devices which can do DVFS (CPU, MMC, LCD, etc) and those may need
a different performance state of the domain for their individual OPPs
and so we can't have this property in the device all the time.

Does this make sense ?

No. From the definition for power-domain-opp

"+- power-domain-opp: This contains phandle to one of the OPP nodes of
the master
+  power domain. This specifies the minimum required OPP of the master
domain for
+  the functioning of the device in this OPP (where this property is present).
+  This property can only be set for a device if the device node contains the
+  "power-domains" property. Also, either all or none of the OPP nodes in an OPP
+  table should have it set."

In the above example, you are violating the next to last sentence.

Though, I'm now confused by what the last sentence means.

Rob
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