diff options
| -rw-r--r-- | drivers/cpufreq/amd-pstate.c | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/drivers/cpufreq/amd-pstate.c b/drivers/cpufreq/amd-pstate.c index 76419762c04f..9aa220a0e3fe 100644 --- a/drivers/cpufreq/amd-pstate.c +++ b/drivers/cpufreq/amd-pstate.c @@ -1749,11 +1749,37 @@ static int __init amd_pstate_set_driver(int mode_idx) */ static bool amd_cppc_supported(void) { + struct cpuinfo_x86 *c = &cpu_data(0); + bool warn = false; + if ((boot_cpu_data.x86 == 0x17) && (boot_cpu_data.x86_model < 0x30)) { pr_debug_once("CPPC feature is not supported by the processor\n"); return false; } + /* + * If the CPPC feature is disabled in the BIOS for processors that support MSR-based CPPC, + * the AMD Pstate driver may not function correctly. + * Check the CPPC flag and display a warning message if the platform supports CPPC. + * Note: below checking code will not abort the driver registeration process because of + * the code is added for debugging purposes. + */ + if (!cpu_feature_enabled(X86_FEATURE_CPPC)) { + if (cpu_feature_enabled(X86_FEATURE_ZEN1) || cpu_feature_enabled(X86_FEATURE_ZEN2)) { + if (c->x86_model > 0x60 && c->x86_model < 0xaf) + warn = true; + } else if (cpu_feature_enabled(X86_FEATURE_ZEN3) || cpu_feature_enabled(X86_FEATURE_ZEN4)) { + if ((c->x86_model > 0x10 && c->x86_model < 0x1F) || + (c->x86_model > 0x40 && c->x86_model < 0xaf)) + warn = true; + } else if (cpu_feature_enabled(X86_FEATURE_ZEN5)) { + warn = true; + } + } + + if (warn) + pr_warn_once("The CPPC feature is supported but currently disabled by the BIOS.\n" + "Please enable it if your BIOS has the CPPC option.\n"); return true; } |