From c10e50a469b5ec91eabf653526a22bdce03a9bca Mon Sep 17 00:00:00 2001 From: Dhananjay Ugwekar Date: Fri, 4 Oct 2024 12:23:04 +0000 Subject: [PATCH] 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: 3ca7bc818d8c ("cpufreq: amd-pstate: Add guided mode control support via sysfs") Signed-off-by: Dhananjay Ugwekar Reviewed-by: Mario Limonciello Link: https://lore.kernel.org/r/20241004122303.94283-1-Dhananjay.Ugwekar@amd.com Signed-off-by: Mario Limonciello --- drivers/cpufreq/amd-pstate.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index 15e201d5e911..4cf2ac5694cb 100644 --- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -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; }