[PATCH 09/29] ARM: shmobile: r8a7791/koelsch dts: Add DVFS parameters into cpu0 node for r8a7791
Simon Horman
horms+renesas at verge.net.au
Sun Jun 22 19:28:18 PDT 2014
From: Gaku Inami <gaku.inami.xw at bp.renesas.com>
Add needed information inside CPU0 for the generic cpufreq-cpu0 driver.
- voltage-tolerance = 1%
It reflects the tolerance for the CPU voltage defined inside the OPP
table. Due to the lack of proper OPP definition, use an arbitrary safe
value.
- clock-latency = 300 us
Approximate worst-case latency to do a full DVFS transition for every
OPPs. Due to the lack of HW information, use an arbitrary safe value.
Note: The term transition-latency will be more accurate to define this
value since the clock transition latency is not the only parameter that
will define the overall DVFS transition.
- operating-points = < kHz - uV >
List of 6 operating points. All of them are using the same voltage
since DVS is not supported in R-CAR Gen2.
- clocks
phandle to the CPU clock source. This clock source is used for all the
2 CortexA15 located inside the same cluster.
Signed-off-by: Gaku Inami <gaku.inami.xw at bp.renesas.com>
Acked-by: Magnus Damm <damm at opensource.se>
Signed-off-by: Simon Horman <horms+renesas at verge.net.au>
---
arch/arm/boot/dts/r8a7791-koelsch.dts | 4 ++++
arch/arm/boot/dts/r8a7791.dtsi | 11 +++++++++++
2 files changed, 15 insertions(+)
diff --git a/arch/arm/boot/dts/r8a7791-koelsch.dts b/arch/arm/boot/dts/r8a7791-koelsch.dts
index 95331d7..b2e6616 100644
--- a/arch/arm/boot/dts/r8a7791-koelsch.dts
+++ b/arch/arm/boot/dts/r8a7791-koelsch.dts
@@ -429,3 +429,7 @@
regulator-always-on;
};
};
+
+&cpu0 {
+ cpu0-supply = <&vdd_dvfs>;
+};
diff --git a/arch/arm/boot/dts/r8a7791.dtsi b/arch/arm/boot/dts/r8a7791.dtsi
index d683982..b639006 100644
--- a/arch/arm/boot/dts/r8a7791.dtsi
+++ b/arch/arm/boot/dts/r8a7791.dtsi
@@ -45,6 +45,17 @@
compatible = "arm,cortex-a15";
reg = <0>;
clock-frequency = <1500000000>;
+ voltage-tolerance = <1>; /* 1% */
+ clocks = <&cpg_clocks R8A7791_CLK_Z>;
+ clock-latency = <300000>; /* 300 us */
+
+ /* kHz - uV - OPPs unknown yet */
+ operating-points = <1500000 1000000>,
+ <1312500 1000000>,
+ <1125000 1000000>,
+ < 937500 1000000>,
+ < 750000 1000000>,
+ < 375000 1000000>;
};
cpu1: cpu at 1 {
--
2.0.0.rc2
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