Doing a little of research, I found this note in a Google Android repository:
* MSM7201A Levels 3-6 all correspond to 1.2V, level 7 corresponds to 1.325V. */
I’m guessing levels 0-2 are undefined, or maybe they set some lower voltage. There is also apparently some checking done to check if the voltage level is valid for that frequency, so I’ll have to do more digging to check on that. Hopefully this clears some questions people were having with the voltage setting – I’ll see if I can update the settings.
Just for comparison, on boot, the processor defaults to 528MHz at 1.325V.
edit: level 0 seems to be significant:
76 { 19200, ACPU_PLL_TCXO, 0, 0, 19200, 0, VDD_0, 0, 0, 8 },
77 { 61440, ACPU_PLL_0, 4, 3, 61440, 0, VDD_0, 0, 0, 8 },
78 { 81920, ACPU_PLL_0, 4, 2, 40960, 1, VDD_0, 0, 0, 8 },
79 { 96000, ACPU_PLL_1, 1, 7, 48000, 1, VDD_0, 0, 0, 9 },
but as to what voltage level it corresponds to, I have no idea. probably some sleep voltage level.. maybe 1.1V?.