On Tue, 27 Aug 2024, Perry Yuan wrote: > From: Perry Yuan <Perry.Yuan@xxxxxxx> > > There are some firmware parameters that need to be configured > when a CPU core is brought online or offline. > > when CPU is online, it will initialize the workload classification > parameters to CPU firmware which will trigger the workload class ID > updating function. > > Once the CPU is going to offline, it will need to disable the workload > classification function and clear the history. > > Signed-off-by: Perry Yuan <Perry.Yuan@xxxxxxx> > --- > drivers/platform/x86/amd/hfi/hfi.c | 90 ++++++++++++++++++++++++++++++ > 1 file changed, 90 insertions(+) > > diff --git a/drivers/platform/x86/amd/hfi/hfi.c b/drivers/platform/x86/amd/hfi/hfi.c > index cd5f2b708ebf..57b642c4c522 100644 > --- a/drivers/platform/x86/amd/hfi/hfi.c > +++ b/drivers/platform/x86/amd/hfi/hfi.c > @@ -154,6 +154,7 @@ static int __percpu *amd_hfi_ipcc_scores; > > static int amd_set_hfi_ipcc_score(struct amd_hfi_cpuinfo *info, int cpu); > static int update_hfi_ipcc_scores(struct amd_hfi_data *amd_hfi_data); > +static int amd_hfi_set_state(unsigned int cpu, bool state); Unnecessary. > static int find_cpu_index_by_apicid(unsigned int target_apicid) > { > @@ -318,6 +319,87 @@ static int amd_set_hfi_ipcc_score(struct amd_hfi_cpuinfo *hfi_cpuinfo, int cpu) > return 0; > } > > +static int amd_hfi_set_state(unsigned int cpu, bool state) > +{ > + int ret; > + > + ret = wrmsrl_on_cpu(cpu, AMD_WORKLOAD_CLASS_CONFIG, state); > + if (ret) > + return ret; > + > + return wrmsrl_on_cpu(cpu, AMD_WORKLOAD_HRST, 0x1); > +} > + > +/* > + * amd_hfi_online() - Enable workload classification on @cpu > + * @cpu: CPU in which the workload classification will be enabled > + * > + */ > +static int amd_hfi_online(unsigned int cpu) > +{ > + struct amd_hfi_cpuinfo *hfi_info = per_cpu_ptr(&amd_hfi_cpuinfo, cpu); > + struct amd_hfi_classes *hfi_classes; > + int ret; > + > + if (WARN_ON_ONCE(!hfi_info)) Can this ever trigger?? > + return -EINVAL; Definitely wrong error code to return since this has nothing to do with user input being invalid. > + if (!zalloc_cpumask_var(&hfi_info->cpus, GFP_KERNEL)) > + return -ENOMEM; > + > + mutex_lock(&hfi_cpuinfo_lock); Use guard(). > + cpumask_set_cpu(cpu, hfi_info->cpus); > + > + /* > + * Check if @cpu as an associated, initialized and ranking data must be filled > + */ > + hfi_classes = hfi_info->amd_hfi_classes; > + if (!hfi_classes) > + goto unlock; > + > + /* Enable the workload classification interface */ > + ret = amd_hfi_set_state(cpu, true); > + if (ret) > + pr_err("wct enable failed for cpu %d\n", cpu); Use %u for unsigned int. > + > + mutex_unlock(&hfi_cpuinfo_lock); > + return 0; > + > +unlock: > + free_cpumask_var(hfi_info->cpus); > + mutex_unlock(&hfi_cpuinfo_lock); > + return ret; > +} > + > +/* > + * amd_hfi_offline() - Disable workload classification on @cpu > + * @cpu: CPU in which the workload classification will be disabled > + * > + * Remove @cpu from those covered by its HFI instance. > + * > + */ > +static int amd_hfi_offline(unsigned int cpu) > +{ > + struct amd_hfi_cpuinfo *hfi_info = &per_cpu(amd_hfi_cpuinfo, cpu); > + int ret; > + > + if (WARN_ON_ONCE(!hfi_info)) > + return -EINVAL; > + > + mutex_lock(&hfi_cpuinfo_lock); > + > + /* Disable the workload classification interface */ > + ret = amd_hfi_set_state(cpu, false); > + if (ret) > + pr_err("wct disable failed for cpu %d\n", cpu); %u > + > + mutex_unlock(&hfi_cpuinfo_lock); > + > + free_cpumask_var(hfi_info->cpus); > + > + return 0; > +} > + > static int update_hfi_ipcc_scores(struct amd_hfi_data *amd_hfi_data) > { > int cpu; > @@ -467,6 +549,14 @@ static int amd_hfi_probe(struct platform_device *pdev) > if (ret) > goto err_exit; > > + ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "x86/amd_hfi:online", > + amd_hfi_online, > + amd_hfi_offline); > + if (ret < 0) { > + pr_warn("failed to setup cpuhp state! (%d)\n", ret); > + return ret; > + } > + > dev_dbg(&pdev->dev, "%s driver registered.\n", pdev->name); > > return 0; > -- i.