The dynamic power consumption of a device is proportional to the
square of voltage (V) and the clock frequency (f). It can be expressed as

Pdyn = dynamic-power-coefficient * V^2 * f.

The dynamic-power-coefficient property represents an indicative
running time dynamic power coefficient in fundamental units of
mw/MHz/uVolt^2 and can be used in the above formula to calculate the
dynamic power in mW.

Signed-off-by: Punit Agrawal <punit.agra...@arm.com>
Cc: Rob Herring <robh...@kernel.org>
Cc: Mark Rutland <mark.rutl...@arm.com>
---
 Documentation/devicetree/bindings/arm/cpus.txt | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/Documentation/devicetree/bindings/arm/cpus.txt 
b/Documentation/devicetree/bindings/arm/cpus.txt
index d6b794c..c32bfac 100644
--- a/Documentation/devicetree/bindings/arm/cpus.txt
+++ b/Documentation/devicetree/bindings/arm/cpus.txt
@@ -239,6 +239,21 @@ nodes to be present and contain the properties described 
below.
                Definition: Specifies the syscon node controlling the cpu core
                            power domains.
 
+       - dynamic-power-coefficient
+               Usage: optional
+               Value type: <prop-encoded-array>
+               Definition: A u32 value that represents an indicative
+                           running time dynamic power coefficient in
+                           fundamental units of mW/MHz/uVolt^2.
+
+                           The dynamic energy consumption of the CPU
+                           is proportional to the square of the
+                           Voltage (V) and the clock frequency (f).
+
+                           Pdyn = dynamic-power-coefficient * V^2 * f
+
+                           where voltage is in uV, frequency is in MHz.
+
 Example 1 (dual-cluster big.LITTLE system 32-bit):
 
        cpus {
-- 
2.1.4

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to