Commit c10e50a4 authored by Dhananjay Ugwekar's avatar Dhananjay Ugwekar Committed by Mario Limonciello
Browse files

cpufreq/amd-pstate: Fix amd_pstate mode switch on shared memory systems 



While switching the driver mode between active and passive, Collaborative
Processor Performance Control (CPPC) is disabled in
amd_pstate_unregister_driver(). But, it is not enabled back while registering
the new driver (passive or active). This leads to the new driver mode not
working correctly, so enable it back in amd_pstate_register_driver().

Fixes: 3ca7bc81 ("cpufreq: amd-pstate: Add guided mode control support via sysfs")
Signed-off-by: default avatarDhananjay Ugwekar <Dhananjay.Ugwekar@amd.com>
Reviewed-by: default avatarMario Limonciello <mario.limonciello@amd.com>
Link: https://lore.kernel.org/r/20241004122303.94283-1-Dhananjay.Ugwekar@amd.com


Signed-off-by: default avatarMario Limonciello <mario.limonciello@amd.com>
parent 8cf0b939

drivers/cpufreq/amd-pstate.c

+10 −0
Original line number Diff line number Diff line
@@ -1201,11 +1201,21 @@ static int amd_pstate_register_driver(int mode) 
		return -EINVAL;



	cppc_state = mode;



	ret = amd_pstate_enable(true);

	if (ret) {

		pr_err("failed to enable cppc during amd-pstate driver registration, return %d\n",

		       ret);

		amd_pstate_driver_cleanup();

		return ret;

	}



	ret = cpufreq_register_driver(current_pstate_driver);

	if (ret) {

		amd_pstate_driver_cleanup();

		return ret;

	}



	return 0;

}