The configuration of voltage regulators can be modified. Configuration changes usually override hardware default settings.
The most common configuration change is setting the output voltage for a regulator rail. Other examples include modifying pgood thresholds and overcurrent settings.
Regulator configuration occurs early in the system boot before regulators have been enabled (turned on).
Configuration is defined for a voltage regulator using the configuration object in the JSON config file.
This object specifies actions to run, such as pmbus_write_vout_command and i2c_write_byte.
During the system boot, the systemd service file phosphor-regulators-config.service is started. This runs the regsctl
utility. This utility invokes the D-Bus configure
method on the phosphor-regulators
application. phosphor-regulators
will perform the configuration defined in the JSON config file.
If an error occurs while executing actions to perform configuration: