[U-Boot] About "sf probe" command

[wzc0066]

Hello, i feel confused about the parameter of "sf probe" command.
Such as "sf  probe 0" or "sf  probe 1"

I have a 4M SPI Flash on my board, how should i specify the parameter of "sf
probe" ?
And what means of these parameters ?  ( the help info of this command is too
small which displayed in u-boot console )


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wzc0066