[PATCH 1/4] power: regulator: Trigger probe of regulators which are always-on or boot-on

[Marek Vasut]

On 7/29/24 7:38 AM, Svyatoslav Ryhel wrote:

[...]

>> The PMIC is on I2C, DM_PMIC enabled in SPL, both buck4 and buck5
>> regulators are enabled in SPL, have regulator-always-on and
>> regulator-boot-on and bootph-pre-ram properties.
>>
>> This seems similar enough, right ?
>>
> Yes, though SPL must remain as small as possible and you propose add
> there i2c driver,  PMIC driver, PMIC regulator drivers, PMIC GPIO
> drivers along with relocation of all this stuff. It is not optimal at
> all.

Sure, if you do use DM_PMIC for PMIC on I2C bus, then you also need 
DM_I2C . You can also do non-DM PMIC configuration in SPL, non-DM in SPL 
is allowed.

>> What is the problem you observe on tegra 3 ?
> i2c line fails since it probes in spl with your patch, but it does not
> relocate and then probes once more after relocation. Probe fails along
> with all devices on same line.

Could it be that you either have to:
- Add DM_I2C to tegra 3 SPL
- Remove bootph-* from DT to remove the regulator node from SPL
- /delete-property/ regulator-always-on; and /delete-property/ 
regulator-boot-on; in -u-boot.dtsi to prevent the regulator from being 
enabled in SPL ?

regulator-always-on means the regulator has to be enabled 
unconditionally, and the system software has no other way to test 
whether the regulator is enabled but access the PMIC, so that is why the 
regulator is probed, even if it is early.