The amd_pstate mode parameter will allow user to select which amd pstate
working mode as booting mode, amd_pstate instance or amd_pstate_epp instance.

1) amd_pstate instance is depending on the target operation mode.
2) amd_pstate_epp instance is depending on the set_policy operation mode.It
   is also called active mode that AMD SMU has EPP algorithm to control the
   CPU runtime frequency according to the EPP set value and workload.

Signed-off-by: Perry Yuan <Perry.Yuan@amd.com>
---
 drivers/cpufreq/amd-pstate.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c
index f52b8f2fe529..14a275c22aff 100644
--- a/drivers/cpufreq/amd-pstate.c
+++ b/drivers/cpufreq/amd-pstate.c
@@ -63,6 +63,10 @@ module_param(shared_mem, bool, 0444);
 MODULE_PARM_DESC(shared_mem,
 		 "enable amd-pstate on processors with shared memory solution (false = disabled (default), true = enabled)");
 
+static bool epp_enabled = false;
+module_param(epp_enabled, bool, 0444);
+MODULE_PARM_DESC(epp_enabled, "Enable energy performance preference (EPP) control");
+
 static struct cpufreq_driver amd_pstate_driver;
 
 /**
-- 
2.34.1