PMF has a generic interface defined via PMF ACPI fn9 for influencing fan
policy during mode switch.

PMF ACPI fn9 will normally be invoked when AMDPMF needs to change the fan
table index for the EC. When AMDPMF is loaded this function will be invoked
to change fan speed. OEM can also choose to report the actual fan table
index and fan RPM to PMF through OEM structure.

This information will be communicated by PMF driver to customer BIOS.
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Shyam Sundar S K <Shyam-sundar.S-k@amd.com>
Link: https://lore.kernel.org/r/20220802151149.2123699-7-Shyam-sundar.S-k@amd.comSigned-off-by: Hans de Goede <hdegoede@redhat.com>