From d9a7e9df731670acdc69e81748941ad338f47fab Mon Sep 17 00:00:00 2001 From: Doug Smythies Date: Sun, 12 Sep 2021 11:50:29 -0700 Subject: cpufreq: intel_pstate: Override parameters if HWP forced by BIOS If HWP has been already been enabled by BIOS, it may be necessary to override some kernel command line parameters. Once it has been enabled it requires a reset to be disabled. Suggested-by: Rafael J. Wysocki Signed-off-by: Doug Smythies Signed-off-by: Rafael J. Wysocki --- drivers/cpufreq/intel_pstate.c | 22 ++++++++++++++-------- 1 file changed, 14 insertions(+), 8 deletions(-) (limited to 'drivers/cpufreq') diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c index 1097f826ad70..8c176b7dae41 100644 --- a/drivers/cpufreq/intel_pstate.c +++ b/drivers/cpufreq/intel_pstate.c @@ -3205,11 +3205,15 @@ static int __init intel_pstate_init(void) if (boot_cpu_data.x86_vendor != X86_VENDOR_INTEL) return -ENODEV; - if (no_load) - return -ENODEV; - id = x86_match_cpu(hwp_support_ids); if (id) { + bool hwp_forced = intel_pstate_hwp_is_enabled(); + + if (hwp_forced) + pr_info("HWP enabled by BIOS\n"); + else if (no_load) + return -ENODEV; + copy_cpu_funcs(&core_funcs); /* * Avoid enabling HWP for processors without EPP support, @@ -3219,8 +3223,7 @@ static int __init intel_pstate_init(void) * If HWP is enabled already, though, there is no choice but to * deal with it. */ - if ((!no_hwp && boot_cpu_has(X86_FEATURE_HWP_EPP)) || - intel_pstate_hwp_is_enabled()) { + if ((!no_hwp && boot_cpu_has(X86_FEATURE_HWP_EPP)) || hwp_forced) { hwp_active++; hwp_mode_bdw = id->driver_data; intel_pstate.attr = hwp_cpufreq_attrs; @@ -3235,7 +3238,11 @@ static int __init intel_pstate_init(void) goto hwp_cpu_matched; } + pr_info("HWP not enabled\n"); } else { + if (no_load) + return -ENODEV; + id = x86_match_cpu(intel_pstate_cpu_ids); if (!id) { pr_info("CPU model not supported\n"); @@ -3314,10 +3321,9 @@ static int __init intel_pstate_setup(char *str) else if (!strcmp(str, "passive")) default_driver = &intel_cpufreq; - if (!strcmp(str, "no_hwp")) { - pr_info("HWP disabled\n"); + if (!strcmp(str, "no_hwp")) no_hwp = 1; - } + if (!strcmp(str, "force")) force_load = 1; if (!strcmp(str, "hwp_only")) -- cgit v1.2.3