On 6/15/2021 8:35 PM, Ulf Hansson wrote:

On Thu, 27 May 2021 at 08:13, Rajendra Nayak [off-list ref] wrote:

quoted

While most devices within power-domains which support performance states,
scale the performance state dynamically, some devices might want to
set a static/default performance state while the device is active.
These devices typically would also run off a fixed clock and not support
dynamically scaling the device's performance, also known as DVFS techniques.
Add a property 'assigned-performance-states' which client devices can
use to set this default performance state on their power-domains.

Signed-off-by: Rajendra Nayak <redacted>

Rajendra, I think this is ready to be re-spinned on top of the latest
changes for genpd that Rafael recently queued [1].

Thanks Ulf, yes, I plan to re-spin these based on the recent discussions,
re-using the existing required-opps bindings soon.
  

If you would prefer me to do it, then please let me know. Otherwise I
will be awaiting a new version from you.

Kind regards
Uffe

[1]
https://lore.kernel.org/linux-pm/CAJZ5v0i0FD-F7tN=AJNEY5HVVTCNuciLT4hCqdoS5bgF5WdmaA@mail.gmail.com/ (local)

quoted

---
  .../devicetree/bindings/power/power-domain.yaml    | 50 ++++++++++++++++++++++
  1 file changed, 50 insertions(+)

diff --git a/Documentation/devicetree/bindings/power/power-domain.yaml b/Documentation/devicetree/bindings/power/power-domain.yaml
index aed51e9..88cebf2 100644
--- a/Documentation/devicetree/bindings/power/power-domain.yaml
+++ b/Documentation/devicetree/bindings/power/power-domain.yaml

@@ -66,6 +66,19 @@ properties:
        by the given provider should be subdomains of the domain specified
        by this binding.

+  assigned-performance-states:
+    $ref: /schemas/types.yaml#/definitions/uint32-array
+    description:
+       Some devices might need to configure their power domains in a default
+       performance state while the device is active. These devices typically
+       would also run off a fixed clock and not support dynamically scaling the
+       device's performance, also known as DVFS techniques. The list of performance
+       state values should correspond to the list of power domains specified as part
+       of the power-domains property. Each cell corresponds to one power-domain.
+       A value of 0 can be used for power-domains with no performance state
+       requirement. In case the power-domains have OPP tables associated, the values
+       here would typically match with one of the entries in the OPP table.
+
  required:
    - "#power-domain-cells"

@@ -131,3 +144,40 @@ examples:
              min-residency-us = <7000>;
          };
      };
+
+  - |
+    parent4: power-controller@12340000 {
+        compatible = "foo,power-controller";
+        reg = <0x12340000 0x1000>;
+        #power-domain-cells = <0>;
+    };
+
+    parent5: power-controller@43210000 {
+        compatible = "foo,power-controller";
+        reg = <0x43210000 0x1000>;
+        #power-domain-cells = <0>;
+        operating-points-v2 = <&power_opp_table>;
+
+        power_opp_table: opp-table {
+            compatible = "operating-points-v2";
+
+            power_opp_low: opp1 {
+                opp-level = <16>;
+            };
+
+            rpmpd_opp_ret: opp2 {
+                opp-level = <64>;
+            };
+
+            rpmpd_opp_svs: opp3 {
+                opp-level = <256>;
+            };
+        };
+    };
+
+    child4: consumer@12341000 {
+        compatible = "foo,consumer";
+        reg = <0x12341000 0x1000>;
+        power-domains = <&parent4>, <&parent5>;
+        assigned-performance-states = <0>, <256>;
+    };
--

QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation

-- 
QUALCOMM INDIA, on behalf of Qualcomm Innovation Center, Inc. is a member
of Code Aurora Forum, hosted by The Linux Foundation