[PATCH 5.10 079/103] cpufreq: intel_pstate: Override parameters if HWP forced by BIOS
From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: 2021-09-27 17:14:48
Also in:
lkml
Subsystem:
cpu frequency scaling framework, intel pstate driver, the rest · Maintainers:
"Rafael J. Wysocki", Viresh Kumar, Srinivas Pandruvada, Len Brown, Linus Torvalds
From: Doug Smythies <redacted> [ Upstream commit d9a7e9df731670acdc69e81748941ad338f47fab ] 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 <rafael@kernel.org> Signed-off-by: Doug Smythies <redacted> Signed-off-by: Rafael J. Wysocki <redacted> Signed-off-by: Sasha Levin <sashal@kernel.org> --- drivers/cpufreq/intel_pstate.c | 22 ++++++++++++++-------- 1 file changed, 14 insertions(+), 8 deletions(-)
diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
index 44a5d15a7572..1686705bee7b 100644
--- a/drivers/cpufreq/intel_pstate.c
+++ b/drivers/cpufreq/intel_pstate.c@@ -3035,11 +3035,15 @@ 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,
@@ -3049,8 +3053,7 @@ 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;
@@ -3061,7 +3064,11 @@ 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");
@@ -3138,10 +3145,9 @@ 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"))
--
2.33.0