On 09-02-19, 20:02, Chen Yu wrote:
> On Dell Inc. XPS13 9333, the BIOS changes the value of
> MSR_IA32_MISC_ENABLE_TURBO_DISABLE at runtime (e.g., when
> the power source changes), the maximum frequency of the
> CPU is not updated accordingly. This is due to the policy's
> cpuinfo.max is not updated when _PPC notifier fires.
> 
> Fix this problem by updating the policy's cpuinfo.max
> and broadcast the _PPC notifier to all online CPUs.
> 
> Link: https://bugzilla.kernel.org/show_bug.cgi?id=200759
> Reported-and-tested-by: Gabriele Mazzotta <gabriele....@gmail.com>
> Originally-by: Srinivas Pandruvada <srinivas.pandruv...@linux.intel.com>
> Signed-off-by: Chen Yu <yu.c.c...@intel.com>
> ---
>  drivers/acpi/processor_perflib.c | 16 ++++++++++++++--
>  drivers/cpufreq/cpufreq.c        |  2 ++
>  drivers/cpufreq/intel_pstate.c   | 15 ++++++++++++++-
>  3 files changed, 30 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/acpi/processor_perflib.c 
> b/drivers/acpi/processor_perflib.c
> index a303fd0e108c..737dbf5aa7f7 100644
> --- a/drivers/acpi/processor_perflib.c
> +++ b/drivers/acpi/processor_perflib.c
> @@ -63,6 +63,10 @@ module_param(ignore_ppc, int, 0644);
>  MODULE_PARM_DESC(ignore_ppc, "If the frequency of your machine gets wrongly" 
> \
>                "limited by BIOS, this should help");
>  
> +static int broadcast_ppc;
> +module_param(broadcast_ppc, int, 0644);
> +MODULE_PARM_DESC(broadcast_ppc, "Broadcast the ppc to all online CPUs");
> +
>  #define PPC_REGISTERED   1
>  #define PPC_IN_USE       2
>  
> @@ -180,8 +184,16 @@ void acpi_processor_ppc_has_changed(struct 
> acpi_processor *pr, int event_flag)
>               else
>                       acpi_processor_ppc_ost(pr->handle, 0);
>       }
> -     if (ret >= 0)
> -             cpufreq_update_policy(pr->id);
> +     if (ret >= 0) {
> +             if (broadcast_ppc) {
> +                     int cpu;
> +
> +                     for_each_possible_cpu(cpu)
> +                             cpufreq_update_policy(cpu);
> +             } else {
> +                     cpufreq_update_policy(pr->id);
> +             }
> +     }
>  }
>  
>  int acpi_processor_get_bios_limit(int cpu, unsigned int *limit)
> diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
> index e35a886e00bc..95e08816b512 100644
> --- a/drivers/cpufreq/cpufreq.c
> +++ b/drivers/cpufreq/cpufreq.c
> @@ -2237,6 +2237,8 @@ static int cpufreq_set_policy(struct cpufreq_policy 
> *policy,
>  
>       policy->min = new_policy->min;
>       policy->max = new_policy->max;
> +     policy->cpuinfo.max_freq = new_policy->cpuinfo.max_freq;
> +     policy->cpuinfo.min_freq = new_policy->cpuinfo.min_freq;
>       trace_cpu_frequency_limits(policy);
>  
>       policy->cached_target_freq = UINT_MAX;
> diff --git a/drivers/cpufreq/intel_pstate.c b/drivers/cpufreq/intel_pstate.c
> index dd66decf2087..e1881313c396 100644
> --- a/drivers/cpufreq/intel_pstate.c
> +++ b/drivers/cpufreq/intel_pstate.c
> @@ -2081,11 +2081,24 @@ static void intel_pstate_adjust_policy_max(struct 
> cpufreq_policy *policy,
>  
>  static int intel_pstate_verify_policy(struct cpufreq_policy *policy)
>  {
> +     int max_freq;
>       struct cpudata *cpu = all_cpu_data[policy->cpu];
>  
>       update_turbo_state();
> +     max_freq = intel_pstate_get_max_freq(cpu);
> +
> +     if (acpi_ppc && policy->max == policy->cpuinfo.max_freq &&
> +         max_freq != policy->cpuinfo.max_freq) {
> +             /*
> +              * System was not running under any constraints, but the
> +              * current max possible frequency is changed. So reset
> +              * policy limits.
> +              */
> +             policy->cpuinfo.max_freq = policy->max = max_freq;
> +     }
> +
>       cpufreq_verify_within_limits(policy, policy->cpuinfo.min_freq,
> -                                  intel_pstate_get_max_freq(cpu));
> +                                  max_freq);
>  
>       if (policy->policy != CPUFREQ_POLICY_POWERSAVE &&
>           policy->policy != CPUFREQ_POLICY_PERFORMANCE)

By TURBO I believe this is about boost-frequencies and you should use
that infrastructure to make it work, isn't it ?

-- 
viresh

Reply via email to