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ARM: shmobile: r8a7790/lager dts: Add DVFS parameters into cpu0 node …
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…for r8a7790

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 the valid Vmin voltage is not documented in the HW spec.
- clocks
  phandle to the CPU clock source. This clock source is used for all the
  4 CortexA15 located inside the same cluster.

Signed-off-by: Benoit Cousson <bcousson+renesas@baylibre.com>
[gaku.inami.xw@bp.renesas.com: Change the setting of OPPs for ES2.0]
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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Benoit Cousson authored and Simon Horman committed Jun 17, 2014
1 parent 05f72e0 commit b989e13
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4 changes: 4 additions & 0 deletions arch/arm/boot/dts/r8a7790-lager.dts
Original file line number Diff line number Diff line change
Expand Up @@ -338,3 +338,7 @@
regulator-always-on;
};
};

&cpu0 {
cpu0-supply = <&vdd_dvfs>;
};
11 changes: 11 additions & 0 deletions arch/arm/boot/dts/r8a7790.dtsi
Original file line number Diff line number Diff line change
Expand Up @@ -44,6 +44,17 @@
compatible = "arm,cortex-a15";
reg = <0>;
clock-frequency = <1300000000>;
voltage-tolerance = <1>; /* 1% */
clocks = <&cpg_clocks R8A7790_CLK_Z>;
clock-latency = <300000>; /* 300 us */

/* kHz - uV - OPPs unknown yet */
operating-points = <1400000 1000000>,
<1225000 1000000>,
<1050000 1000000>,
< 875000 1000000>,
< 700000 1000000>,
< 350000 1000000>;
};

cpu1: cpu@1 {
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