On Thu, 10 Oct 2024, Mario Limonciello 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> > Co-developed-by: Mario Limonciello <mario.limonciello@xxxxxxx> > Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx> > --- > v2: > * Rebase > --- > drivers/platform/x86/amd/hfi/hfi.c | 90 +++++++++++++++++++++++++++++- > 1 file changed, 89 insertions(+), 1 deletion(-) > > diff --git a/drivers/platform/x86/amd/hfi/hfi.c b/drivers/platform/x86/amd/hfi/hfi.c > index c0065ba0ed18..c969ee7ea5ee 100644 > --- a/drivers/platform/x86/amd/hfi/hfi.c > +++ b/drivers/platform/x86/amd/hfi/hfi.c > @@ -244,6 +244,89 @@ 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 > + * > + * Return: 0 on success, negative error code on failure > + */ > +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)) > + return -EINVAL; > + > + 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); CPU Should wct too be capitalized? Is it okay to return 0 when this error occurs? > + > + 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. > + * > + * Return: 0 on success, negative error code on failure > + */ > +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); guard or scoped_guard. > + > + /* Disable the workload classification interface */ > + ret = amd_hfi_set_state(cpu, false); > + if (ret) > + pr_err("wct disable failed for cpu %d\n", cpu); > + > + 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; > @@ -362,8 +445,13 @@ static int amd_hfi_probe(struct platform_device *pdev) > if (ret) > goto out; > > + ret = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "x86/amd_hfi:online", > + amd_hfi_online, amd_hfi_offline); > + if (ret < 0) > + goto out; return ret; > + > out: > - return ret; > + return ret < 0 ? ret : 0; > } > > static struct platform_driver amd_hfi_driver = { > -- i.