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ARM: shmobile: r8a7791/koelsch dts: Add DVFS parameters into cpu0 nod…
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…e for r8a7791

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@bp.renesas.com>
Acked-by: Magnus Damm <damm@opensource.se>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>
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Gaku Inami authored and Simon Horman committed Jun 17, 2014
1 parent 1d41f36 commit a57004e
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4 changes: 4 additions & 0 deletions arch/arm/boot/dts/r8a7791-koelsch.dts
Original file line number Diff line number Diff line change
Expand Up @@ -429,3 +429,7 @@
regulator-always-on;
};
};

&cpu0 {
cpu0-supply = <&vdd_dvfs>;
};
11 changes: 11 additions & 0 deletions arch/arm/boot/dts/r8a7791.dtsi
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Expand Up @@ -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@1 {
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