On Thu, Jun 7, 2018 at 8:08 AM Adam Ford <aford173@xxxxxxxxx> wrote:
>
> I am running some tests on the 4.17 kernel, and notices the operating
> frequency does not change the operating voltage.
>
My bad...It appears as if I was using a older DTB file. Once I
rebuilt the DTB, everything was fine.
Sorry for the noise. Please disregard. it seems to be working
adam
> The omap36xx.dtsi defines the operating points as follows:
>
> cpus {
> /* OMAP3630/OMAP37xx 'standard device' variants OPP50 to OPP130 */
> cpu: cpu@0 {
> operating-points = <
> /* kHz uV */
> 300000 1012500
> 600000 1200000
> 800000 1325000
> >;
> clock-latency = <300000>; /* From legacy driver */
> };
> };
>
> Because of this, I would expect the system to increase/decrease the
> voltage when going between operating frequncies of 300MHz, 600MHz, and
> 800 MHz when we assign a proper regulator to the cpu.
>
> In the device tree for the logicpd-torpedo SOM, we set the cpu0 supply to
> cpus {
> cpu@0 {
> cpu0-supply = <&vcc>;
> };
> };
>
> vcc is defined in twl4030.dtsi to be
>
> vcc: regulator-vdd1 {
> compatible = "ti,twl4030-vdd1";
> regulator-min-microvolt = <600000>;
> regulator-max-microvolt = <1450000>;
> };
>
> Based on the above info, I am reading
> /sys/devices/platform/68000000.ocp/48070000.i2c/i2c-0/0-0048/48070000.i2c:twl@48:regulator-vdd1/regulator/regulator.11/microvolts
> to read the operating voltage of vcc/vdd1 which I would expect to
> change based on the the processor operating frequency.
>
> When I set the scaling governor to userspace and then manually set the
> frequencies to 300, 600 and 800 MHz, I would expect the voltages to
> move between 1012500, 1200000, and 1325000 respectively.
>
> Unfortunately, the regulator always returns a value of 1200000 microvolts.
>
> I am going to go back and bisect, but before I spend the time, I
> thought I'd ask if others have seen this or have any ideas on what I
> might be doing wrong.
>
> Thanks,
>
> adam
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