2022-01-24 19:01:51

by Cristian Marussi

[permalink] [raw]
Subject: [PATCH 2/6] dt-bindings: firmware: arm,scmi: Add atomic_threshold optional property

SCMI protocols in the platform can optionally signal to the OSPM agent
the expected execution latency for a specific resource/operation pair.

Introduce an SCMI system wide optional property to describe a global time
threshold which can be configured on a per-platform base to determine the
opportunity, or not, for an SCMI command advertised to have a higher
latency than the threshold, to be considered for atomic operations:
high-latency SCMI synchronous commands should be preferably issued in the
usual non-atomic mode.

Cc: Rob Herring <[email protected]>
Cc: [email protected]
Signed-off-by: Cristian Marussi <[email protected]>
---
.../devicetree/bindings/firmware/arm,scmi.yaml | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/Documentation/devicetree/bindings/firmware/arm,scmi.yaml b/Documentation/devicetree/bindings/firmware/arm,scmi.yaml
index eae15df36eef..8edda54dff5b 100644
--- a/Documentation/devicetree/bindings/firmware/arm,scmi.yaml
+++ b/Documentation/devicetree/bindings/firmware/arm,scmi.yaml
@@ -81,6 +81,14 @@ properties:
'#size-cells':
const: 0

+ atomic_threshold:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description:
+ An optional time value, expressed in microseconds, representing the
+ threshold above which, on this platform, any SCMI command advertised to
+ have a higher execution latency, should not be used in atomic mode, even
+ if requested. If left unconfigured defaults to zero.
+
arm,smc-id:
$ref: /schemas/types.yaml#/definitions/uint32
description:
@@ -264,6 +272,8 @@ examples:
#address-cells = <1>;
#size-cells = <0>;

+ atomic_threshold = <10000>;
+
scmi_devpd: protocol@11 {
reg = <0x11>;
#power-domain-cells = <1>;
--
2.17.1