[PATCHv5 2/5] ARM: dts: Odroid-XU3 Enable TMU at Exynos5422 base

Anand Moon linux.amoon at gmail.com
Sat May 23 22:19:41 PDT 2015


On 24 May 2015 at 10:03, Krzysztof Kozlowski <k.kozlowski at samsung.com> wrote:
> 2015-05-24 2:35 GMT+09:00 Anand Moon <linux.amoon at gmail.com>:
>> Hi Krzysztof,
>>
>> I did some debugging on the this using powerdebug utility.
>> Using  LDO7 to control TMU seams to me correct option compared to BUCK3.
>>
>> Setting LDO7 to control TMU I observed  following output on powerdebug.
>> I observed that the power drawn by the board on Odroid show is much
>> less compare to BUCK3 on the same setup.
>> I can see the HDMI output on Odroid-V2 display screen.
>> I have done some stress testing on this configuration and It worked correctly.
>>
>> Powerdebug output using LDO7
>> ---------------------------------------------------------------------------------------------------------------
>> PowerDebug 0.7.3     Clocks  Regulators  Sensors  Gpio
>> Name        Status      State       Type        Users       Microvolts
>>  Min u-volts Max u-volts
>> phy                                             0           0
>>  0           0
>> phy                                             0           0
>>  0           0
>> vdd_ldo1                enabled     voltage     0           1000000
>>  1000000     1000000
>> LDO1                                            0           0
>>  0           0
>> LDO2                    enabled     voltage     0           1800000
>>  0           0
>> vdd_ldo3                enabled     voltage     0           1800000
>>  1800000     1800000
>> LDO3                                            0           0
>>  0           0
>> LDO4                    enabled     voltage     0           1800000
>>  0           0
>> vdd_ldo5                enabled     voltage     0           1800000
>>  1800000     1800000
>> LDO5                                            0           0
>>  0           0
>> vdd_ldo6                enabled     voltage     0           1000000
>>  1000000     1000000
>> hdmi        okay                                0           0
>>  0           0
>> hdmi        okay                                0           0
>>  0           0
>> LDO6                                            0           0
>>  0           0
>> vdd_ldo7                enabled     voltage     0           1800000
>>  1800000     1800000
>> hdmi        okay                                0           0
>>  0           0
>> tmu         okay                                0           0
>>  0           0
>> tmu         okay                                0           0
>>  0           0
>> tmu         okay                                0           0
>>  0           0
>> tmu         okay                                0           0
>>  0           0
>> tmu         okay                                0           0
>>  0           0
>> LDO7                                            0           0
>>  0           0
>> vdd_ldo8                enabled     voltage     0           1800000
>>  1800000     1800000
>> LDO8                                            0           0
>>  0           0
>> vdd_ldo9                enabled     voltage     0           3000000
>>  3000000     3000000
>> LDO9                                            0           0
>>  0           0
>>
>> Powerdebug output using BUCK3.
>> --------------------------------------------------------------------------------------------------------------------------
>> PowerDebug 0.7.3     Clocks  Regulators  Sensors  Gpio
>> Name        Status      State       Type        Users       Microvolts
>>  Min u-volts Max u-volts
>> LDO21                   disabled    voltage     0           1800000
>>  0           0
>> LDO22                   disabled    voltage     0           1200000
>>  0           0
>> LDO23                   enabled     voltage     0           1100000
>>  0           0
>> tsp_io                  enabled     voltage     0           2800000
>>  2800000     2800000
>> LDO24                                           0           0
>>  0           0
>> LDO25                   disabled    voltage     0           1800000
>>  0           0
>> vdd_ldo26               enabled     voltage     0           3000000
>>  3000000     3000000
>> LDO26                                           0           0
>>  0           0
>> LDO27                   enabled     voltage     0           1000000
>>  0           0
>> LDO28                   disabled    voltage     0           3300000
>>  0           0
>> LDO29                   disabled    voltage     0           1800000
>>  0           0
>> LDO30                   disabled    voltage     0           1800000
>>  0           0
>> LDO31                   disabled    voltage     0           1800000
>>  0           0
>> LDO32                   disabled    voltage     0           1800000
>>  0           0
>> LDO33                   disabled    voltage     0           1800000
>>  0           0
>> LDO34                   disabled    voltage     0           3000000
>>  0           0
>> LDO35                   disabled    voltage     0           1600000
>>  0           0
>> LDO36                   disabled    voltage     0           1800000
>>  0           0
>> LDO37                   disabled    voltage     0           1800000
>>  0           0
>> LDO38                   disabled    voltage     0           2800000
>>  0           0
>> vdd_mif                 enabled     voltage     0           1100000
>>  800000      1300000
>> BUCK1                                           0           0
>>  0           0
>> vdd_arm                 enabled     voltage     0           1000000
>>  800000      1500000
>> BUCK2                                           0           0
>>  0           0
>> vdd_int                 enabled     voltage     0           1000000
>>  800000      1400000
>> tmu         okay                                0           0
>>  0           0
>> tmu         okay                                0           0
>>  0           0
>> tmu         okay                                0           0
>>  0           0
>> tmu         okay                                0           0
>>  0           0
>> tmu         okay                                0           0
>>  0           0
>> BUCK3                                           0           0
>>  0           0
>> vdd_g3d                 enabled     voltage     0           1000000
>>  800000      1400000
>> BUCK4                                           0           0
>>  0           0
>> vdd_mem                 enabled     voltage     0           1200000
>>  800000      1400000
>> BUCK5                                           0           0
>>  0           0
>> vdd_kfc                 enabled     voltage     0           1025000
>>  800000      1500000
>>
>> So I would like to go with LDO7.
>>
>> Please share your thoughts.
>
> I don't understand how grepping through /sys/class/regulator helps in
> making this decision. I just don't get it. Can you please explain it
> to me?
>
> Best regards,
> Krzysztof

Hi Krzysztof,

I am just trying to understand the how the DTS changes get mapped internally.
If their seem to be a problem with the changes, then I could figure it
out but doing some testing.

-Anand Moon



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