_CPC info

Hi All,
I am try to write a driver for performance tuning. I am new to ACPI spec and going through this I need to get the performance values from the PCC subspace registers. I am trying to use acpi_read and by passing passing the info through Generic Address Register.

By doing this I get an error saying Unknown Subspace Id. I do feel it is not the right way to get the register value and at the same point unable to understand how to do this.

Could someone point me or give an idea how this should be made to work.

Thanks,
Anand